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HomeMy WebLinkAboutSD-22-10 - Supplemental - 0500 Old Farm Road (42) Attachment 1: Narrative, Location Map, and Soils Map EASTVIEW 1. Introduction Krebs and Lansing Consulting Engineers Inc. (K&L) are writing on behalf of O’Brien Brothers to apply for a State Stormwater Discharge Permit pursuant to General Permit 3- 9050 for the next phase of the EASTVIEW project located on Kimball Avenue, O’Brien Farm Road, and Old Farm Road in South Burlington, Vermont. 2. Project Description The Eastview project is adjacent to the Hillside @ O’Brien Farm project. The project proposes a mix of single family, duplex, and tri-plex residential units, as well as future commercial and industrial development lots. The project proposes seven new roadways including Leo Lane, a relocation of a portion of Old Farm Road, an extension of O’Brien Farm Road, Daniel Drive, Barn Road, Mabel Way, and Potash Road. An additional alley, entitled Eastview Lane is also proposed. Shared driveways will serve new residences on Lots 24 and 36 for the project. The proposed stormwater treatment practices include seven new Gravel Wetlands. Forebays are provided for pre-treatment of non-rooftop runoff for each Gravel Wetland. Simple Disconnections will be used to treat rooftop runoff from the back of eight units along Mabel Way, and for the meandering gravel paths throughout the project. 3. Existing Condition Phase 1 of the adjacent Hillside @ O’Brien Farm project is nearly built out, including most of the City Streets and single family and duplex units. The remaining portion of the site west of Old Farm Road is currently open meadow, or being used for construction staging and stockpiling. There is an existing house located at 205 Old Farm Road that will be demolished as part of the project. The west portion of the site is bordered by Kimball Avenue to the North, Old Farm Road to the east, and residential development to the west and south. This portion of the site slopes east to west away from Old Farm Road towards Kennedy Drive and Kimball Avenue. The portion of the project located east of Old Farm Road is mostly meadow, with some wooded areas and wetlands. The existing homes at 100 and 150 Old Farm Road will be demolished as part of the project. 200 Old Farm Road is not part of the project, and will remain. The Historic Barn between 150 and 200 Old Farm Road will also remain as part of the project. The east portion of the site is bordered by Kimball Avenue to the north, Potash Brook to the east, Old Farm Road to the west, and commercial lots in the Tilley Drive area to the south. This portion of the site generally slopes west to east, away from Old Farm Road, except for a crest where the existing houses and barn are located. Eastview Stormwater Narrative 2 Existing soil types on the site are a combination of Farmington Extremely Rocky Loam, Vergennes Clay, Covington Silty Clay, Enosburg & Whately soils, and Adams-Windsor loamy sands. Except for the Adams-Winsdsor soils, these soils are all mapped as type “D” soils, indicating a low infiltrative capacity and a high degree of runoff. Adams Windsor soils are classified as type A by the U.S. Soil Conservation Service, which normally indicates a low degree of runoff and high infiltrative capacity. However, on-site soil testing, as well as observation during construction, indicates a high seasonal groundwater table at less than three feet below existing ground surface throughout the site. This was verified through on- site testing wherever Adams Windsor soils are mapped on the site. See the Pre Development Watershed Map for soil test pit locations and logs. Due to the presence of high seasonal water table, these soils are also effectively type “D” soils. 4. Existing Stormwater System Stormwater Permit #7815-INDS was obtained in September 2017 for Phase 1 of the Hillside development. This permit also incorporated previously permitted infrastructure from Stormwater discharge Permit #1-1520. Existing permitted stormwater infrastructure includes Extended Detention Ponds 1, 2, and 3, Wet Ponds A and B, Infiltration Basin A, six grass channels, and four infiltration trenches. Wet Pond B and the infiltration trenches have not been constructed at this time. Wet Pond B will be converted to a Gravel Wetland #1 as part of a separate application for commercial development on Lots 10-15. Previously referenced, but not permitted, Wet Pond C, will be converted to Gravel Wetland #2 as part of the same application. There is no existing stormwater infrastructure on the east side of Old Farm Road. Old Farm Road itself either sheet flows to both sides, or flows to ditches that outlet to existing infrastructure on Hinesburg Road and Kimball Avenue respectively. 5. Proposed Stormwater System: The proposed stormwater collection, treatment, and detention system will utilize mostly enclosed drainage and seven new gravel wetlands. We have continued our numbering system for discharge points and gravel wetlands from the adjacent, related Hillside project. • The watershed draining to SN004 includes the portions of the project treated by Gravel Wetland #3. This area essentially includes Leo Lane and the houses, cottages, duplex, and triplexes fronting on Leo Lane. A portion of the existing Old Farm Road will also drain to this area. Because Gravel wetland #3 is not located adjacent to a potential discharge point, a large diameter pipe run has been designed to outlet the wetland to a discharge point under Kennedy Drive. • The watershed draining to SN006 includes the portions of the project treated by Gravel Wetland #4. This area includes Daniel Drive, Barn Road, a portion of Mabel Way and the houses, cottages, and duplexes fronting these roads. A portion of the existing Old Farm Road will also drain to this area. Gravel Wetland #4 outlets to an existing swale draining to the discharge point. • The watershed draining to SN007 includes the portions of the project treated by Gravel Wetland #5. This area includes most of Mabel Way and Eastview Lane, along with the houses fronting these roads. A portion of the existing Old Farm Road and Eastview Stormwater Narrative 3 development around the Historic Barn will also drain to this area. Gravel Wetland #4 outlets near the discharge point in the Class 2 wetlands to the east. • The watershed draining to SN008 includes the portions of the project treated by Gravel Wetlands #6A and #6B. This area includes the relocated Old Farm Road, a portion of the houses along Eastview Lane, a portion of Mabel Way and the associated residences, along with the shared driveway and houses located on Lot 24. Both Gravel Wetland #6A and #6B are not located adjacent to potential discharge points. Therefore, large diameter pipe runs have been designed to outlet the gravel wetlands near the culvert under Kimball Avenue. • The watershed draining to SN009 includes the portions of the project treated by Gravel Wetland #7. This area includes northerly portion of Potash Road. Gravel Wetland #7 has been designed to accommodate future development on the adjacent industrial/commercial lots, but we are not permitting impervious area on the lots at this time. Gravel Wetland #7 outlets near the discharge point in the Class 2 wetlands to the east. • The watershed draining to SN010 includes the portions of the project treated by Gravel Wetland #8. This area includes southerly portion of Potash Road. Gravel Wetland #8 has been designed to accommodate future development on the adjacent industrial/commercial lots, but we are not permitting impervious area on the lots at this time. Gravel Wetland #8 outlets near an existing swale that will convey runoff to Potash Brook. All of the gravel wetlands feature forebay pre-treatment, and two interior cells. All outlets will be stabilized with rip-rap, and non-erosive. Conveyances from the project to the treatment practices are generally sheet flow or gutters/downspouts from roofs to enclosed drainage (catch basins and piping) in the roads. a) Description of Impervious Area: We offer the following summary of impervious areas by watershed: Discharge Point New Impervious (acres) 4 3.75 6 3.02 7 3.98 8 4.39 9 0.7 10 1.0 TOTAL 16.84 While there is “existing impervious” on the site from Old Farm Road and existing houses, we have treated this as “New” in order to offset portions of the Eastview Stormwater Narrative 4 project that are impossible to direct to treatment practices. These areas include the entrances to the relocated Old Farm Road and Potash Road, as well as the proposed recreation path along Kimball Avenue. b) Receiving Body: i) S/N004: Wetlands in Potash Brook watershed ii) S/N006: Wetlands in Potash Brook watershed iii) S/N007: Wetlands in Potash Brook watershed iv) S/N008: Wetlands in Potash Brook watershed v) S/N009: Wetlands in Potash Brook watershed vi) S/N010: Potash Brook c) Fish Habitat Designation for Receiving Water: Warm d) Description of compliance with each of the treatment standards in the 2017 VSMM including the treatment practices or waivers used to meet each of the following standards: i) Post-Construction Soil Depth and Quality Standard: This standard will be met via two options outlined in the VSMM. Option 1: Areas outside of construction will be left undisturbed and protected from compaction during construction. This option will apply only to the far westerly portion of the site. Option 3: Remove and stockpile existing topsoil during construction. On site soil testing indicates and existing sandy loam topsoil layer on the site ranging from 7-13 inches in depth. Given that much of the finish site will be covered in building or paving, there will be an excess of existing topsoil to re store other disturbed areas such as setbacks, vegetated islands, swales, and side-slopes. Compost will be incorporated into the existing topsoil stockpile if needed to achieve 4% organic content. ii) Groundwater Recharge Standard: The Groundwater Recharge standard is waived because all of the developed areas are located in type “D” soils. iii) Water Quality Treatment Standard (WQV): (a) S/N004: WQv will be met for S/N 004 via the use of Gravel Wetland #3. The stone voids in the gravel wetland will store 50% of the WQv draining to the wetland. The remaining 50% WQv is provided by extended detention using small diameter orifices to release the remaining WQv over a 24 hour period. Pre-treatment is provided in a forebay. (b) S/N006: WQv will be met for S/N 006 via the use of Gravel Wetland #4. The stone voids in the gravel wetland will store 50% of the WQv draining to the wetland. The remaining 50% WQv is provided by extended detention using small diameter orifices to release the remaining WQv over a 24 hour period. Pre-treatment is provided in a forebay. Eastview Stormwater Narrative 5 (c) S/N007: WQv will be met for S/N 007 via the use of Gravel Wetland #5. The stone voids in the gravel wetland will store 50% of the WQv draining to the wetland. The remaining 50% WQv is provided by extended detention using small diameter orifices to release the remaining WQv over a 24 hour period. Pre-treatment is provided in a forebay. (d) S/N008: WQv will be met for S/N 008 via the use of Gravel Wetlands #6A and #6B. For each of the wetlands the stone voids in the gravel wetland will store 50% of the WQv draining to each wetland. The remaining 50% WQv is provided by extended detention using small diameter orifices to release the remaining WQv over a 24 hour period. Pre-treatment is provided in a forebay. (e) S/N009: WQv will be met for S/N 009 via the use of Gravel Wetlands #7. The stone voids in the gravel wetland will store 50% of the WQv draining to the wetland. The remaining 50% WQv is provided by extended detention using small diameter orifices to release the remaining WQv over a 24 hour period. Pre-treatment is provided in a forebay. (f) S/N010: WQv will be met for S/N 010 via the use of Gravel Wetlands #8 The stone voids in the gravel wetland will store 50% of the WQv draining to the wetland. The remaining 50% WQv is provided by extended detention using small diameter orifices to release the remaining WQv over a 24 hour period. Pre-treatment is provided in a forebay. iv) Channel Protection Standard (CPV): (a) S/N004: The Cpv standard is met by the use Gravel Wetland #3. The gravel wetland will feature an outlet structure using low flow orifices to provide the required detention time, or use the minimum orifice size required. (b) S/N006: The Cpv standard is met by the use Gravel Wetland #4. The gravel wetland will feature an outlet structure using low flow orifices to provide the required detention time, or use the minimum orifice size required. (c) S/N007: The Cpv standard is met by the use Gravel Wetland #5. The gravel wetland will feature an outlet structure using low flow orifices to provide the required detention time, or use the minimum orifice size required. (d) S/N008: The Cpv standard is met by the use Gravel Wetlands #6A and #6B. The gravel wetlands will feature outlet structures using low flow orifices to provide the required detention times, or use the minimum orifice size required. (e) S/N009: The Cpv standard is met by the use Gravel Wetland #7. The gravel wetland will feature an outlet structures using low flow orifices to provide the required detention time, or use the minimum orifice size required. (f) S/N0010: The Cpv standard is met by the use Gravel Wetland #8. The gravel wetland will feature an outlet structure using low flow orifices to provide the required detention time, or use the minimum orifice size required. Eastview Stormwater Narrative 6 v) Overbank Flood Protection Standard (QP10): (1) S/N004: The Overbank Flood Protection Standard is met by the use of Gravel Wetland #3. The gravel wetland uses a controlled outlet device to limit post development peak flows to below pre development levels for the 10 year, 24 hour storm event. (2) S/N006: The Overbank Flood Protection Standard is met by the use of Gravel Wetland #4. The gravel wetland uses a controlled outlet device to limit post development peak flows to below pre development levels for the 10 year, 24 hour storm event. (3) S/N007: The Overbank Flood Protection Standard is met by the use of Gravel Wetland #5. The gravel wetland uses a controlled outlet device to limit post development peak flows to below pre development levels for the 10 year, 24 hour storm event. (4) S/N008: The Overbank Flood Protection Standard is met by the use of Gravel Wetland #6A and #6B. The gravel wetlands use controlled outlet devices to limit post development peak flows to below pre development levels for the 10 year, 24 hour storm event. (5) S/N009: The Overbank Flood Protection Standard is met by the use of Gravel Wetland #7. The gravel wetland uses a controlled outlet device to limit post development peak flows to below pre development levels for the 10 year, 24 hour storm event. (6) S/N010: The Overbank Flood Protection Standard is met by the use of Gravel Wetland #8. The gravel wetland uses a controlled outlet device to limit post development peak flows to below pre development levels for the 10 year, 24 hour storm event. vi) Extreme Flood Protection Standard (QP100): (1) S/N004: The Extreme Flood Protection Standard is met by the use of Gravel Wetland #3. The gravel wetland uses a controlled outlet device to limit post development peak flows to below pre development levels for the 100 year, 24 hour storm event. (2) S/N006: The Extreme Flood Protection Standard is met by the use of Gravel Wetland #4. The gravel wetland uses a controlled outlet device to limit post development peak flows to below pre development levels for the 100 year, 24 hour storm event. (3) S/N007: The Extreme Flood Protection Standard is met by the use of Gravel Wetland #5. The gravel wetland uses a controlled outlet device to limit post development peak flows to below pre development levels for the 100 year, 24 hour storm event. (4) S/N008: The Extreme Flood Protection Standard is met by the use of Gravel Wetland #6A and #6B. The gravel wetlands use controlled outlet devices to limit post development peak flows to below pre development levels for the 100 year, 24 hour storm event. Eastview Stormwater Narrative 7 (5) S/N009: The Extreme Flood Protection Standard is met by the use of Gravel Wetland #7. The gravel wetland uses a controlled outlet device to limit post development peak flows to below pre development levels for the 100 year, 24 hour storm event. (6) S/N010: The Extreme Flood Protection Standard is met by the use of Gravel Wetland #8. The gravel wetland uses a controlled outlet device to limit post development peak flows to below pre development levels for the 100 year, 24 hour storm event. The following items are attached for review: • Attachment 1: Narrative: Narrative, Location Map, and Soils Map. • Attachment 2: Workbooks: STP Selection Tool and Standards Compliance Workbook • Attachment 3: Worksheets: STP and waiver worksheets, grouped by discharge point • Attachment 4: Modeling: Runoff modeling and calculations demonstrating compliance with the applicable treatment standards. Eastview Stormwater Narrative 8 Location Map [Insert project specific location map here. You may download topographic map from the Natural Resource Atlas. Please show the site outline, the location of the discharge point(s) and receiving waters. The scale of the location map should be between 1:20,000 and 1:40,000.] See Attached Location Map. Eastview Stormwater Narrative 9 Soils Map [Insert project specific soils map here. Soils information can be found at the Web Soil Survey website. Hydrologic Soil Groups— “HSGs” shall be overlaid with site outline. Soils information can also be provided as data layer on an existing or proposed condition plan sheet (if included as a data layer on one of the plan sheets please indicate that here] See Attached Soils Map. KENNEDY D R I V E OLD FARM ROADK IM B A L L A V ENU EPotash BrookHINESBURG ROAD INTERS T A T E 8 9 LIMIT OF EASTVIEW Potash Brook X X X X SN003 X SN005 SN002 SN001 SN004 X SN006 X SN007 X SN008 X SN009 X SN010 DATE: 04/01/22 LOCATION MAP SCALE: 1" = 1000' South Burlington, Vermont EASTVIEW 164 Main Street, Suite 201 P: (802) 878-0375 Colchester, Vermont 05446 email@krebsandlansing.com KIMBALL AVENUE & OLD FARM ROAD SITE MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Map Unit Polygons Soil Map Unit Lines Soil Map Unit Points Special Point Features Blowout Borrow Pit Clay Spot Closed Depression Gravel Pit Gravelly Spot Landfill Lava Flow Marsh or swamp Mine or Quarry Miscellaneous Water Perennial Water Rock Outcrop Saline Spot Sandy Spot Severely Eroded Spot Sinkhole Slide or Slip Sodic Spot Spoil Area Stony Spot Very Stony Spot Wet Spot Other Special Line Features Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:15,800. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Chittenden County, Vermont Survey Area Data: Version 24, Sep 9, 2021 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Jun 18, 2020—Jun 20, 2020 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Soil Map—Chittenden County, Vermont (EASTVIEW) Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 4/5/2022 Page 2 of 4 Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI AdA Adams and Windsor loamy sands, 0 to 5 percent slopes 116.6 13.9% AdB Adams and Windsor loamy sands, 5 to 12 percent slopes 65.7 7.8% AdD Adams and Windsor loamy sands, 12 to 30 percent slopes 44.7 5.3% AdE Adams and Windsor loamy sands, 30 to 60 percent slopes 14.9 1.8% An Alluvial land 0.0 0.0% Be Beaches 4.4 0.5% BlA Belgrade and Eldridge soils, 0 to 3 percent slopes 6.3 0.8% BlB Belgrade and Eldridge soils, 3 to 8 percent slopes 7.9 0.9% Cv Covington silty clay 87.8 10.5% DdA Duane and Deerfield soils, 0 to 5 percent slopes 66.0 7.9% DdB Duane and Deerfield soils, 5 to 12 percent slopes 1.8 0.2% EwA Enosburg and Whately soils, 0 to 3 percent slopes 32.3 3.9% EwB Enosburg and Whately soils, 3 to 8 percent slopes 61.0 7.3% FaC Farmington extremely rocky loam, 5 to 20 percent slopes 24.3 2.9% FsB Farmington-Stockbridge rocky loams, 5 to 12 percent slopes 33.7 4.0% FsC Farmington-Stockbridge rocky loams, 12 to 20 percent slopes 2.4 0.3% Fu Fill land 1.4 0.2% HnA Hinesburg fine sandy loam, 0 to 3 percent slopes 4.9 0.6% HnB Hinesburg fine sandy loam, 3 to 8 percent slopes 22.6 2.7% HnC Hinesburg fine sandy loam, 8 to 15 percent slopes 6.5 0.8% Lf Limerick silt loam, very wet 45.2 5.4% Lh Livingston clay 3.4 0.4% Mp Muck and Peat 25.3 3.0% Soil Map—Chittenden County, Vermont EASTVIEW Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 4/5/2022 Page 3 of 4 Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI Sd Scarboro loam 3.6 0.4% SuB Stockbridge and Nellis soils, 3 to 8 percent slopes, stony 0.2 0.0% VeB Vergennes clay, 2 to 6 percent slopes 134.8 16.1% VeC Vergennes clay, 6 to 12 percent slopes 18.4 2.2% VeD Vergennes clay, 12 to 25 percent slopes 3.2 0.4% Totals for Area of Interest 839.2 100.0% Soil Map—Chittenden County, Vermont EASTVIEW Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 4/5/2022 Page 4 of 4 STP Selection Matrix Project Name: Version 5/8/2017 Discharge Point: Step 1: Is the Water Quality Treatment Standard entirely managed with one or more of the following Tier 1 practices? Infiltration Basins/ Trenches/ Chambers Simple Disconnection Drywells Disconnection to Filter Strips and Vegetated Buffers Bioretention (designed to infiltrate) Dry Swales (designed to infiltrate) Filters (designed to infiltrate)Permeable Pavement1  Reforestation1 2 1. These practices do not require specific justification due to feasibility limitations Step 2: Assess the feasibility of using Tier 1 Practices Infiltration Basin/ Trench/ ChamberDrywellBioretention (infiltrating)Simple DisconnectionDisconnection to Filter Strips or Vegetated BufferDry Swales (infiltrating)Filters (infiltrating)Practice Availability for Water Quality Treatment?Not  Feasible Not  Feasible Not  Feasible Yes Yes Not  Feasible Not  Feasible Response Not  Feasible Not  Feasible Not  Feasible n/a n/a Not  Feasible Not  Feasible Available Available Available Available Available Available Available Available Available Available Available Available Available Available n/a n/a n/a Available Available n/a n/a n/a n/a n/a Available n/a n/a n/a n/a n/a n/a n/a Available n/a n/a Available n/a Available n/a n/a Available Available Available Available Available n/a n/a Available Available Available Available n/a n/a n/a n/a n/a Available n/a n/a n/a n/a n/a n/a Feasibility Restriction Practice Availability Based on Restrictions Eastview S/N 004 Proceed to Step  2 Complete the matrix below in its entirety for each drainage area. Tier 1 Practices are available to meet the Water  Quality Treatment Standard. If using one of these  practices, stop here. If additional site constraints  exist other than those listed here, proceed to Step 3. Do underlying soils have an infiltration rate of less  than 0.2 inches per hour, as confirmed by field  geotechnical tests or are classified as Hydrologic  Soil Group D according to the NRCS Soil survey? Will runoff to the practice include discharge from a  hotspot landuse or activity? Is the site a brownfield or contaminated site where  infiltration is restricted or where infiltration would  increase the threat of pollution migration, as  confirmed in writing by the Department’s Waste  Management and Prevention Division? Is the slope of the vegetated buffer greater than  15% Is the slope of the filter strip greater than 15% Is the slope of the vegetated buffer greater than  8% Are natural slopes where an infiltration trench or  basin could be sited greater than 15% Bottom of practice would be below seasonal high  water table Seasonal high water table or bedrock would be less  than 1 foot from the bottom of the practice. Seasonal high water table or bedrock would be less  than 3 feet from the bottom of the practice. Yes No Yes No Yes No Yes No Yes No Yes Yes No No Yes No No Yes No Yes No Yes STP Selection Matrix ‐ SN4 Page 10 of 17 Available Available Available n/a n/a Available Available Available Available Available n/a n/a Available Available Available Available Available n/a n/a Available Available Available Available Available n/a n/a Available Available Available Available Available n/a n/a Available Available Available Available Available Available Available Available Available Step 3: Other feasibility constraints for remaining Tier 1 and Tier 2 practices 2 Provide written feasibilty justification below or list attachments Will the practice be located within 150 feet of a  drinking water source located in an unconfined  aquifer? Will the practice be located within 75 feet down‐ gradient of a wastewater disposal area system,  within 35 feet up‐gradient or 75 feet down‐ gradient of a wastewater disposal system? If the the use of a Tier 1  or Tier 2 Practice is infeasible for reasons beyond those listed in Step 2 of the STP Selection Matrix, a designer may  submit site specific detailed feasibility justification that such practices are not feasible following the guidance in Section 2.2.4.1 of the 2017  VSMM.  Only after completion of the STP Selection Matrix and determination that Tier and Tier 2 Practices are infeasible shall a designer  consider Tier 3 Practices or existing stormwater infrastructure for meeting the Water Quality Treatment Standard (WQTS) on the project  site. Will the practice be located within 100 feet of a  drinking water source located in bedrock or a  confined unconsolidated aquifer? Will the practice be located within Zone 1 or Zone  2 of a public community groundwater source  protection area? Will the practice be located within 200 feet of non‐ transient non‐community groundwater source? Will the practice violate any restrictions of the  Vermont Wastewater and Potable Water Supply  Rules, or their replacement? If, following completion of Step 2 of the STP Selection Tool there are no Tier 1 Practices available for use on the project site, designers shall  consider the use of Tier 2 practices  for treatment of the Water Quality Treatment Standard.   Is the Water Quality Treatment Standard  entirely managed with Tier 2 Practices? Provide written site specific justification below.  Tier 3 Practices may be used to meet the Water  Quality Treatment Standard. Yes Yes Yes No Yes No Yes No Yes Yes No No No No STP Selection Matrix ‐ SN4 Page 11 of 17 STP Selection Matrix Project Name: Version 5/8/2017 Discharge Point: Step 1: Is the Water Quality Treatment Standard entirely managed with one or more of the following Tier 1 practices? Infiltration Basins/ Trenches/ Chambers Simple Disconnection Drywells Disconnection to Filter Strips and Vegetated Buffers Bioretention (designed to infiltrate) Dry Swales (designed to infiltrate) Filters (designed to infiltrate)Permeable Pavement1  Reforestation1 2 1. These practices do not require specific justification due to feasibility limitations Step 2: Assess the feasibility of using Tier 1 Practices Infiltration Basin/ Trench/ ChamberDrywellBioretention (infiltrating)Simple DisconnectionDisconnection to Filter Strips or Vegetated BufferDry Swales (infiltrating)Filters (infiltrating)Practice Availability for Water Quality Treatment?Not  Feasible Not  Feasible Not  Feasible Yes Yes Not  Feasible Not  Feasible Response Not  Feasible Not  Feasible Not  Feasible n/a n/a Not  Feasible Not  Feasible Available Available Available Available Available Available Available Available Available Available Available Available Available Available n/a n/a n/a Available Available n/a n/a n/a n/a n/a Available n/a n/a n/a n/a n/a n/a n/a Available n/a n/a Available n/a Available n/a n/a Available Available Available Available Available n/a n/a Available Available Available Available n/a n/a n/a n/a n/a Available n/a n/a n/a n/a n/a n/a Feasibility Restriction Practice Availability Based on Restrictions Eastview S/N 006 Proceed to Step  2 Complete the matrix below in its entirety for each drainage area. Tier 1 Practices are available to meet the Water  Quality Treatment Standard. If using one of these  practices, stop here. If additional site constraints  exist other than those listed here, proceed to Step 3. Do underlying soils have an infiltration rate of less  than 0.2 inches per hour, as confirmed by field  geotechnical tests or are classified as Hydrologic  Soil Group D according to the NRCS Soil survey? Will runoff to the practice include discharge from a  hotspot landuse or activity? Is the site a brownfield or contaminated site where  infiltration is restricted or where infiltration would  increase the threat of pollution migration, as  confirmed in writing by the Department’s Waste  Management and Prevention Division? Is the slope of the vegetated buffer greater than  15% Is the slope of the filter strip greater than 15% Is the slope of the vegetated buffer greater than  8% Are natural slopes where an infiltration trench or  basin could be sited greater than 15% Bottom of practice would be below seasonal high  water table Seasonal high water table or bedrock would be less  than 1 foot from the bottom of the practice. Seasonal high water table or bedrock would be less  than 3 feet from the bottom of the practice. Yes No Yes No Yes No Yes No Yes No Yes Yes No No Yes No No Yes No Yes No Yes STP Selection Matrix ‐ SN6 Page 12 of 17 Available Available Available n/a n/a Available Available Available Available Available n/a n/a Available Available Available Available Available n/a n/a Available Available Available Available Available n/a n/a Available Available Available Available Available n/a n/a Available Available Available Available Available Available Available Available Available Step 3: Other feasibility constraints for remaining Tier 1 and Tier 2 practices 2 Provide written feasibilty justification below or list attachments Will the practice be located within 150 feet of a  drinking water source located in an unconfined  aquifer? Will the practice be located within 75 feet down‐ gradient of a wastewater disposal area system,  within 35 feet up‐gradient or 75 feet down‐ gradient of a wastewater disposal system? If the the use of a Tier 1  or Tier 2 Practice is infeasible for reasons beyond those listed in Step 2 of the STP Selection Matrix, a designer may  submit site specific detailed feasibility justification that such practices are not feasible following the guidance in Section 2.2.4.1 of the 2017  VSMM.  Only after completion of the STP Selection Matrix and determination that Tier and Tier 2 Practices are infeasible shall a designer  consider Tier 3 Practices or existing stormwater infrastructure for meeting the Water Quality Treatment Standard (WQTS) on the project  site. Will the practice be located within 100 feet of a  drinking water source located in bedrock or a  confined unconsolidated aquifer? Will the practice be located within Zone 1 or Zone  2 of a public community groundwater source  protection area? Will the practice be located within 200 feet of non‐ transient non‐community groundwater source? Will the practice violate any restrictions of the  Vermont Wastewater and Potable Water Supply  Rules, or their replacement? If, following completion of Step 2 of the STP Selection Tool there are no Tier 1 Practices available for use on the project site, designers shall  consider the use of Tier 2 practices  for treatment of the Water Quality Treatment Standard.   Is the Water Quality Treatment Standard  entirely managed with Tier 2 Practices? Provide written site specific justification below.  Tier 3 Practices may be used to meet the Water  Quality Treatment Standard. Yes Yes Yes No Yes No Yes No Yes Yes No No No No STP Selection Matrix ‐ SN6 Page 13 of 17 STP Selection Matrix Project Name: Version 5/8/2017 Discharge Point: Step 1: Is the Water Quality Treatment Standard entirely managed with one or more of the following Tier 1 practices? Infiltration Basins/ Trenches/ Chambers Simple Disconnection Drywells Disconnection to Filter Strips and Vegetated Buffers Bioretention (designed to infiltrate) Dry Swales (designed to infiltrate) Filters (designed to infiltrate)Permeable Pavement1  Reforestation1 2 1. These practices do not require specific justification due to feasibility limitations Step 2: Assess the feasibility of using Tier 1 Practices Infiltration Basin/ Trench/ ChamberDrywellBioretention (infiltrating)Simple DisconnectionDisconnection to Filter Strips or Vegetated BufferDry Swales (infiltrating)Filters (infiltrating)Practice Availability for Water Quality Treatment?Not  Feasible Not  Feasible Not  Feasible Yes Yes Not  Feasible Not  Feasible Response Not  Feasible Not  Feasible Not  Feasible n/a n/a Not  Feasible Not  Feasible Available Available Available Available Available Available Available Available Available Available Available Available Available Available n/a n/a n/a Available Available n/a n/a n/a n/a n/a Available n/a n/a n/a n/a n/a n/a n/a Available n/a n/a Available n/a Available n/a n/a Available Available Available Available Available n/a n/a Available Available Available Available n/a n/a n/a n/a n/a Available n/a n/a n/a n/a n/a n/a Feasibility Restriction Practice Availability Based on Restrictions Eastview S/N 007 Proceed to Step  2 Complete the matrix below in its entirety for each drainage area. Tier 1 Practices are available to meet the Water  Quality Treatment Standard. If using one of these  practices, stop here. If additional site constraints  exist other than those listed here, proceed to Step 3. Do underlying soils have an infiltration rate of less  than 0.2 inches per hour, as confirmed by field  geotechnical tests or are classified as Hydrologic  Soil Group D according to the NRCS Soil survey? Will runoff to the practice include discharge from a  hotspot landuse or activity? Is the site a brownfield or contaminated site where  infiltration is restricted or where infiltration would  increase the threat of pollution migration, as  confirmed in writing by the Department’s Waste  Management and Prevention Division? Is the slope of the vegetated buffer greater than  15% Is the slope of the filter strip greater than 15% Is the slope of the vegetated buffer greater than  8% Are natural slopes where an infiltration trench or  basin could be sited greater than 15% Bottom of practice would be below seasonal high  water table Seasonal high water table or bedrock would be less  than 1 foot from the bottom of the practice. Seasonal high water table or bedrock would be less  than 3 feet from the bottom of the practice. Yes No Yes No Yes No Yes No Yes No Yes Yes No No Yes No No Yes No Yes No Yes STP Selection Matrix ‐ SN3 Page 14 of 17 Available Available Available n/a n/a Available Available Available Available Available n/a n/a Available Available Available Available Available n/a n/a Available Available Available Available Available n/a n/a Available Available Available Available Available n/a n/a Available Available Available Available Available Available Available Available Available Step 3: Other feasibility constraints for remaining Tier 1 and Tier 2 practices 2 Provide written feasibilty justification below or list attachments Will the practice be located within 150 feet of a  drinking water source located in an unconfined  aquifer? Will the practice be located within 75 feet down‐ gradient of a wastewater disposal area system,  within 35 feet up‐gradient or 75 feet down‐ gradient of a wastewater disposal system? If the the use of a Tier 1  or Tier 2 Practice is infeasible for reasons beyond those listed in Step 2 of the STP Selection Matrix, a designer may  submit site specific detailed feasibility justification that such practices are not feasible following the guidance in Section 2.2.4.1 of the 2017  VSMM.  Only after completion of the STP Selection Matrix and determination that Tier and Tier 2 Practices are infeasible shall a designer  consider Tier 3 Practices or existing stormwater infrastructure for meeting the Water Quality Treatment Standard (WQTS) on the project  site. Will the practice be located within 100 feet of a  drinking water source located in bedrock or a  confined unconsolidated aquifer? Will the practice be located within Zone 1 or Zone  2 of a public community groundwater source  protection area? Will the practice be located within 200 feet of non‐ transient non‐community groundwater source? Will the practice violate any restrictions of the  Vermont Wastewater and Potable Water Supply  Rules, or their replacement? If, following completion of Step 2 of the STP Selection Tool there are no Tier 1 Practices available for use on the project site, designers shall  consider the use of Tier 2 practices  for treatment of the Water Quality Treatment Standard.   Is the Water Quality Treatment Standard  entirely managed with Tier 2 Practices? Provide written site specific justification below.  Tier 3 Practices may be used to meet the Water  Quality Treatment Standard. Yes Yes Yes No Yes No Yes No Yes Yes No No No No STP Selection Matrix ‐ SN3 Page 15 of 17 STP Selection Matrix Project Name: Version 5/8/2017 Discharge Point: Step 1: Is the Water Quality Treatment Standard entirely managed with one or more of the following Tier 1 practices? Infiltration Basins/ Trenches/ Chambers Simple Disconnection Drywells Disconnection to Filter Strips and Vegetated Buffers Bioretention (designed to infiltrate) Dry Swales (designed to infiltrate) Filters (designed to infiltrate)Permeable Pavement1  Reforestation1 2 1. These practices do not require specific justification due to feasibility limitations Step 2: Assess the feasibility of using Tier 1 Practices Infiltration Basin/ Trench/ ChamberDrywellBioretention (infiltrating)Simple DisconnectionDisconnection to Filter Strips or Vegetated BufferDry Swales (infiltrating)Filters (infiltrating)Practice Availability for Water Quality Treatment?Not  Feasible Not  Feasible Not  Feasible Yes Yes Not  Feasible Not  Feasible Response Not  Feasible Not  Feasible Not  Feasible n/a n/a Not  Feasible Not  Feasible Available Available Available Available Available Available Available Available Available Available Available Available Available Available n/a n/a n/a Available Available n/a n/a n/a n/a n/a Available n/a n/a n/a n/a n/a n/a n/a Available n/a n/a Available n/a Available n/a n/a Available Available Available Available Available n/a n/a Available Available Available Available n/a n/a n/a n/a n/a Available n/a n/a n/a n/a n/a n/a Feasibility Restriction Practice Availability Based on Restrictions Eastview S/N 008 Proceed to Step  2 Complete the matrix below in its entirety for each drainage area. Tier 1 Practices are available to meet the Water  Quality Treatment Standard. If using one of these  practices, stop here. If additional site constraints  exist other than those listed here, proceed to Step 3. Do underlying soils have an infiltration rate of less  than 0.2 inches per hour, as confirmed by field  geotechnical tests or are classified as Hydrologic  Soil Group D according to the NRCS Soil survey? Will runoff to the practice include discharge from a  hotspot landuse or activity? Is the site a brownfield or contaminated site where  infiltration is restricted or where infiltration would  increase the threat of pollution migration, as  confirmed in writing by the Department’s Waste  Management and Prevention Division? Is the slope of the vegetated buffer greater than  15% Is the slope of the filter strip greater than 15% Is the slope of the vegetated buffer greater than  8% Are natural slopes where an infiltration trench or  basin could be sited greater than 15% Bottom of practice would be below seasonal high  water table Seasonal high water table or bedrock would be less  than 1 foot from the bottom of the practice. Seasonal high water table or bedrock would be less  than 3 feet from the bottom of the practice. Yes No Yes No Yes No Yes No Yes No Yes Yes No No Yes No No Yes No Yes No Yes STP Selection Matrix ‐ SN8 Page 16 of 17 Available Available Available n/a n/a Available Available Available Available Available n/a n/a Available Available Available Available Available n/a n/a Available Available Available Available Available n/a n/a Available Available Available Available Available n/a n/a Available Available Available Available Available Available Available Available Available Step 3: Other feasibility constraints for remaining Tier 1 and Tier 2 practices 1 Provide written feasibilty justification below or list attachments Will the practice be located within 150 feet of a  drinking water source located in an unconfined  aquifer? Will the practice be located within 75 feet down‐ gradient of a wastewater disposal area system,  within 35 feet up‐gradient or 75 feet down‐ gradient of a wastewater disposal system? If the the use of a Tier 1  or Tier 2 Practice is infeasible for reasons beyond those listed in Step 2 of the STP Selection Matrix, a designer may  submit site specific detailed feasibility justification that such practices are not feasible following the guidance in Section 2.2.4.1 of the 2017  VSMM.  Only after completion of the STP Selection Matrix and determination that Tier and Tier 2 Practices are infeasible shall a designer  consider Tier 3 Practices or existing stormwater infrastructure for meeting the Water Quality Treatment Standard (WQTS) on the project  site. Will the practice be located within 100 feet of a  drinking water source located in bedrock or a  confined unconsolidated aquifer? Will the practice be located within Zone 1 or Zone  2 of a public community groundwater source  protection area? Will the practice be located within 200 feet of non‐ transient non‐community groundwater source? Will the practice violate any restrictions of the  Vermont Wastewater and Potable Water Supply  Rules, or their replacement? If, following completion of Step 2 of the STP Selection Tool there are no Tier 1 Practices available for use on the project site, designers shall  consider the use of Tier 2 practices  for treatment of the Water Quality Treatment Standard.   Is the Water Quality Treatment Standard  entirely managed with Tier 2 Practices?Stop. No further justification is needed. Yes Yes Yes No Yes No Yes No Yes Yes No No No No STP Selection Matrix ‐ SN8 Page 17 of 17 Vermont Operational Stormwater Permit - Standards Compliance Workbook The name above will appear on all the discharge point tabs Site Summary Total SN1 SN2 SN3 SN4 SN5 SN6 SN7 SN8 SN9 New 15.84 0.00 0.00 0.00 3.75 0.00 3.02 3.98 4.39 0.70 Redeveloped 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Existing 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Previously Authorized 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Total 15.84 0.00 0.00 0.00 3.75 0.00 3.02 3.98 4.39 0.70Site Area 42.43 0.00 0.00 0.00 6.55 0.00 7.08 15.52 9.19 4.09 0.00000 0.00000 0.00000 44.46044 0.00000 44.45444 44.45584 44.45650 44.45452 0.00000 0.00000 0.00000 -73.16017 0.00000 -73.15299 -73.15221 -73.15097 -73.14914 Receiving Water Potash Brook Wetlands in Potash Brook Watershed Wetlands in Potash Brook Watershed Wetlands in Potash Brook Watershed Wetlands in Potash Brook Watershed Recharge Total SN1 SN2 SN3 SN4 SN5 SN6 SN7 SN8 SN9 Required 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 Provided 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 Standard met?Yes n/a n/a n/a n/a n/a n/a n/a n/a n/a Notes: Water Quality Total SN1 SN2 SN3 SN4 SN5 SN6 SN7 SN8 SN9 Required 1.3648 0.0000 0.0000 0.0000 0.3085 0.0000 0.2560 0.3632 0.3675 0.0695 Provided 1.3647 0.0000 0.0000 0.0000 0.3085 0.0000 0.2560 0.3632 0.3675 0.0695 Standard met?Yes n/a n/a n/a Yes n/a Yes Yes Yes Yes Notes: Channel Protection A minimum WQ V of 0.2" (P*R V ) is required for sites with low impervious (<16.67%). This calculation has not been incorporated into this workbook. Designers should check that the minimum WQV has been met for their site.ImperviousProject Name Do not fill this tab out, apart from the project name and notes. It will auto-populated based on the values on the discharge point tabs. Discharge points (SN) will only show on the summary if an area has been entered on that tab. Areas listed below are those seeking permit coverage. EASTVIEW Latitude Longitude Last Updated 8/28/2018 Summary: Page 3 of 29 Vermont Operational Stormwater Permit - Standards Compliance Workbook Total SN1 SN2 SN3 SN4 SN5 SN6 SN7 SN8 SN9 Standard Applies?0 0 0 Yes 0 Yes Yes Yes Yes Waiver n/a n/a n/a n/a n/a Method n/a n/a n/a Extended Detention n/a Extended Detention Extended Detention Extended Detention Extended Detention HCV 1.8356 0.0000 0.0000 0.0000 0.3950 0.0000 0.3363 0.4884 0.5110 0.1049 TV Provided 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 Notes: Overbank Flood Protection SN1 SN2 SN3 SN4 SN5 SN6 SN7 SN8 SN9 Standard Applies?0 0 0 Yes 0 Yes Yes Yes Yes Pre-Dev Q (cfs)9.63 13.08 23.99 15.27 8.09 Routed, Post-Dev Q (cfs)7.04 7.11 13.45 11.5 0.73 Waiver n/a n/a n/a n/a n/a Notes: Extreme Flood Protection SN1 SN2 SN3 SN4 SN5 SN6 SN7 SN8 SN9 Standard Applies?Yes Yes Yes Yes Yes Pre-Dev Q (cfs)19.35 25.97 48.07 31.87 16.28 Routed, Post-Dev Q (cfs)19.2 24 45.19 22.05 1.24 Waiver n/a n/a n/a n/a n/a Notes: General Notes Last Updated 8/28/2018 Summary: Page 4 of 29 Vermont Operational Stormwater Permit - Standards Compliance Workbook Last Updated 8/28/2018 Summary: Page 5 of 29 Vermont Operational Stormwater Permit - Standards Compliance Workbook General Discharge Point Information Project name Discharge point serial number (e.g. S/N 001) Name of receiving water Latitude (decimal degrees to five decimal places) Longitude (decimal degrees to five decimal places) Precipitation Data NOAA Atlas 14 Storm WQ Storm 1 yr, 24 hr 10 yr, 24 hr 100 yr, 24 hr Precipitation (inches)1.00 1.90 3.25 4.85 Drainage Area Information Landuse A B C D Total Grass 0.000 0.000 0.000 0.000 0.000 Meadow 0.000 0.000 0.000 0.000 0.000 Woods 0.000 0.000 0.000 6.270 6.270 Existing Impervious 0.000 0.000 0.000 0.280 0.280 Impervious previously authorized under 2002 VSMM (not included in calculations)0.000 Total Pre Site Area 6.550 % Landuse A B C D Total Grass 0.000 0.000 0.000 2.800 2.800 Meadow 0.000 0.000 0.000 0.000 0.000 Woods 0.000 0.000 0.000 0.000 0.000 New Impervious 0.000 0.000 0.000 3.750 3.750 57.3% Existing for Permit Coverage (Treated to New Standards) 0.000 0.000 0.000 0.000 0.000 0.0% Existing Impervious Not for Permit Coverage 0.000 0.0% Redeveloped Impervious 0.000 0.0% 0.000 Total Site Area 6.550 Total Impervious for Permit Coverage 3.750 Net Reduced Impervious 0.000 0.0% Reduced Existing Impervious (for redevelopment)0.280 100.0% Average Catchment Slope, Y (%) Hydraulic Length, l (ft) Pre Development 6.12 1500.00 Post Development 6.12 1500.00 EASTVIEW S/N 004 Potash Brook 44.46044 -73.16017 * Preciptation values shall be obtained from Pre Development Land Use (acres) Post Development Land Use (acres) Impervious previously authorized under 2002 VSMM Information for Calculating TC by the Watershed Lag Method Last Updated 8/28/2018 SN4: Page 6 of 29 Vermont Operational Stormwater Permit - Standards Compliance Workbook Runoff Calculations 1 yr, 24-hr 10 yr, 24-hr 100 yr, 24-hr 0.2458 0.7223 1.4129 0.6408 1.2790 2.0863 Tier 1/Runoff Reduction Practices Practice TV (ac-ft)TV (ac-ft) Runoff Reduction Calculations Standard Re WQ CP QP10 QP100 TV Required (ac-ft)0.0000 0.3085 0.3950 0.5567 0.6734 TV Provided (ac-ft)0.0000 0.0000 0.0000 0.0000 0.0000 TV Remaining (ac-ft)0.0000 0.3085 0.3950 0.5567 0.6734 Standard met with HCM?n/a No No No No Post-Development CN n/a 95 92 91 91 CNadj n/a 95 92 91 91 Pre-Development CN n/a n/a 79 78 78 Groundwater Recharge Standard (Re)2 Standard Applicable? ReV 0.0000 Standard met with Tier 1 Practices?n/a Recharge Notes: HSG D Soils Predevelopment runoff volume (ac-ft) Pre-routed, post development runoff volume (ac-ft) List all Tier 1 practices below with the associated treatment volume (T V ). The TV will be applied to all treatment standards, except for Green Roofs, which do not receive recharge or water quality credit. Please include the appropriate STP worksheet(s) with the application. Practice Reason recharge not required (if No is selected):Yes No Last Updated 8/28/2018 SN4: Page 7 of 29 Vermont Operational Stormwater Permit - Standards Compliance Workbook Water Quality Treatment Standard (WQ)1 1 (ac-ft)Apply Reduction? WQV - New & Existing 0.3085 0.0% WQV - Redevelopment 0.0000 100.0%Max 25% applied Total WQV 0.3085 WQV met with Tier 1 practices 0.0000 1 WQV to be met with Tier 2 and/or Tier 3 practices 0.3085 WQV Provided (ac-ft)Tier 0.3085 Tier 3 Total WQV Provided (ac-ft)0.3085 ac-ft Is the WQV Standard met?Yes Water Quality Notes: Channel Protection Standard (CP)2 1 Standard Applicable? Standard Met with HCM?No Provide Extended Detention for:0.641 ac-ft Warm or Cold Water Fishery?→Provide: FALSE Extended Detention STP: CNAdj 92 11.3 (Watershed Lag Method) Channel Protection Notes: % Net Reduction % Removed Existing Impervious (Redevelopment) Is all impervious treated by disconnection? NOTE: Please include a copy of the appropriate STP worksheet(s) with the application. Tier 2 & 3 Water Quality Practice Shallow Surface Wetland The channel protection standard has not been fully met. Either increase Tv credit to fully meet HCM or provide extended detention. 24 hours of extended detention See the Vermont Water Quality Standards for warm and cold water designations OR The Alternative Extended Detention Method (§2.2.5.4) is being used. Gravel Wetland #3 Modeling Info: When demonstrating CP compliance with extended detention in a hydrologic model, use the CN and T C below if the practice being modelled is not a Tier 1 practice. The CN Adj takes into account the reduction in runoff volume achieved through Tier 1 practices. The T C is calculated by the watershed lag method using CN Adj as CN'. Post Development TC (min) Yes No ColdWarm No Yes (WQv met) No Yes No Yes Last Updated 8/28/2018 SN4: Page 8 of 29 Vermont Operational Stormwater Permit - Standards Compliance Workbook Overbank Flood Protection (QP10)1 Standard Applicable? Standard Met with HCM?No STP used: Pre-development peak discharge rate (cfs)9.63 Pre-routed, post-development peak discharge rate (cfs)21.20 Routed, post-development peak discharge rate (cfs)7.04 Pre-Development CN (Flow- weighted composite)78 18.8 CNAdj 91 11.8 Overbank Flood Notes: Extreme Flood Protection (QP100)1 Standard Applicable? Standard Met with HCM?No STP used: Pre-development peak discharge rate (cfs)19.35 Pre-routed, post-development peak discharge rate (cfs)34.12 Routed, post-development peak discharge rate (cfs)19.20 Pre-Development CN (Flow- weighted composite)78 18.9 CNAdj 91 12.0 Extreme Flood Notes: The QP10 standard has not been fully met. Provide additional STPs to ensure post development peak runoff does not exceed pre development peak runoff for the 10 yr, 24 hour storm event. Gravel Wetland #3 Modeling Info: When demonstrating Q P10 compliance in a hydrologic model, use the following CN and TC below, if the practice used to meet Q P10 is not itself a Tier 1 practice. The CN Adj takes into account the reduction in runoff volume achieved through Tier 1 practices. The T C is calculated by the watershed lag method using CN Adj as CN'. Pre Development TC (min)(Watershed Lag Method)Post Development TC (min) Pre Development TC (min)(Watershed Lag Method)Post Development TC (min) The extreme standard has not been fully met. Provide additional STPs to ensure post development peak runoff does not exceed pre development peak runoff for the 100 yr, 24 hour storm event. Gravel Wetland #3 Modeling Info: When demonstrating Q P100 compliance in a hydrologic model, use the following CN and T C below, if the practice used to meet Q P100 is not a Tier 1 practice. The CNAdj takes into account the reduction in runoff volume achieved through runoff reduction practices. The T C is calculated by the watershed lag method using CN Adj as CN'. Yes No Yes No Last Updated 8/28/2018 SN4: Page 9 of 29 Vermont Operational Stormwater Permit - Standards Compliance Workbook General Discharge Point Information Project name Discharge point serial number (e.g. S/N 001) Name of receiving water Latitude (decimal degrees to five decimal places) Longitude (decimal degrees to five decimal places) Precipitation Data NOAA Atlas 14 Storm WQ Storm 1 yr, 24 hr 10 yr, 24 hr 100 yr, 24 hr Precipitation (inches)1.00 1.90 3.25 4.85 Drainage Area Information Landuse A B C D Total Grass 0.000 0.000 0.000 0.000 0.000 Meadow 0.000 0.000 0.000 4.390 4.390 Woods 0.000 0.000 0.000 2.600 2.600 Existing Impervious 0.000 0.000 0.000 0.090 0.090 Impervious previously authorized under 2002 VSMM (not included in calculations)0.000 Total Pre Site Area 7.080 % Landuse A B C D Total Grass 0.000 0.000 0.000 4.060 4.060 Meadow 0.000 0.000 0.000 0.000 0.000 Woods 0.000 0.000 0.000 0.000 0.000 New Impervious 0.000 0.000 0.000 3.020 3.020 42.7% Existing for Permit Coverage (Treated to New Standards) 0.000 0.000 0.000 0.000 0.000 0.0% Existing Impervious Not for Permit Coverage 0.000 0.0% Redeveloped Impervious 0.000 0.0% 0.000 Total Site Area 7.080 Total Impervious for Permit Coverage 3.020 Net Reduced Impervious 0.000 0.0% Reduced Existing Impervious (for redevelopment)0.090 100.0% Average Catchment Slope, Y (%) Hydraulic Length, l (ft) Pre Development 8.87 1070.00 Post Development 8.87 1070.00 EASTVIEW S/N 006 Wetlands in Potash Brook Watershed 44.45444 -73.15299 * Preciptation values shall be obtained from Pre Development Land Use (acres) Post Development Land Use (acres) Impervious previously authorized under 2002 VSMM Information for Calculating TC by the Watershed Lag Method Last Updated 8/28/2018 SN6: Page 10 of 29 Vermont Operational Stormwater Permit - Standards Compliance Workbook Runoff Calculations 1 yr, 24-hr 10 yr, 24-hr 100 yr, 24-hr 0.2553 0.7722 1.5215 0.5916 1.2467 2.0957 Tier 1/Runoff Reduction Practices Practice TV (ac-ft)TV (ac-ft) Runoff Reduction Calculations Standard Re WQ CP QP10 QP100 TV Required (ac-ft)0.0000 0.2560 0.3363 0.4745 0.5742 TV Provided (ac-ft)0.0000 0.0000 0.0000 0.0000 0.0000 TV Remaining (ac-ft)0.0000 0.2560 0.3363 0.4745 0.5742 Standard met with HCM?n/a No No No No Post-Development CN n/a 93 90 89 88 CNadj n/a 93 90 89 88 Pre-Development CN n/a n/a 78 78 78 Groundwater Recharge Standard (Re)2 Standard Applicable? ReV 0.0000 Standard met with Tier 1 Practices?n/a Recharge Notes: HSG D Soils Predevelopment runoff volume (ac-ft) Pre-routed, post development runoff volume (ac-ft) List all Tier 1 practices below with the associated treatment volume (T V ). The TV will be applied to all treatment standards, except for Green Roofs, which do not receive recharge or water quality credit. Please include the appropriate STP worksheet(s) with the application. Practice Reason recharge not required (if No is selected):Yes No Last Updated 8/28/2018 SN6: Page 11 of 29 Vermont Operational Stormwater Permit - Standards Compliance Workbook Water Quality Treatment Standard (WQ)1 1 (ac-ft)Apply Reduction? WQV - New & Existing 0.2560 0.0% WQV - Redevelopment 0.0000 100.0%Max 25% applied Total WQV 0.2560 WQV met with Tier 1 practices 0.0000 1 WQV to be met with Tier 2 and/or Tier 3 practices 0.2560 WQV Provided (ac-ft)Tier 0.2560 Tier 2 Total WQV Provided (ac-ft)0.2560 ac-ft Is the WQV Standard met?Yes Water Quality Notes: Channel Protection Standard (CP)2 1 Standard Applicable? Standard Met with HCM?No Provide Extended Detention for:0.592 ac-ft Warm or Cold Water Fishery?→Provide: FALSE Extended Detention STP: CNAdj 90 7.9 (Watershed Lag Method) Channel Protection Notes: % Net Reduction % Removed Existing Impervious (Redevelopment) Is all impervious treated by disconnection? NOTE: Please include a copy of the appropriate STP worksheet(s) with the application. Tier 2 & 3 Water Quality Practice Gravel Wetland The channel protection standard has not been fully met. Either increase Tv credit to fully meet HCM or provide extended detention. 24 hours of extended detention See the Vermont Water Quality Standards for warm and cold water designations OR The Alternative Extended Detention Method (§2.2.5.4) is being used. Gravel Wetland #4 Modeling Info: When demonstrating CP compliance with extended detention in a hydrologic model, use the CN and T C below if the practice being modelled is not a Tier 1 practice. The CN Adj takes into account the reduction in runoff volume achieved through Tier 1 practices. The T C is calculated by the watershed lag method using CN Adj as CN'. Post Development TC (min) Yes No ColdWarm No Yes (WQv met) No Yes No Yes Last Updated 8/28/2018 SN6: Page 12 of 29 Vermont Operational Stormwater Permit - Standards Compliance Workbook Overbank Flood Protection (QP10)1 Standard Applicable? Standard Met with HCM?No STP used: Pre-development peak discharge rate (cfs)13.08 Pre-routed, post-development peak discharge rate (cfs)24.15 Routed, post-development peak discharge rate (cfs)7.11 Pre-Development CN (Flow- weighted composite)78 12.0 CNAdj 89 8.3 Overbank Flood Notes: Extreme Flood Protection (QP100)1 Standard Applicable? Standard Met with HCM?No STP used: Pre-development peak discharge rate (cfs)25.97 Pre-routed, post-development peak discharge rate (cfs)38.95 Routed, post-development peak discharge rate (cfs)24.00 Pre-Development CN (Flow- weighted composite)78 12.0 CNAdj 88 8.5 Extreme Flood Notes: The QP10 standard has not been fully met. Provide additional STPs to ensure post development peak runoff does not exceed pre development peak runoff for the 10 yr, 24 hour storm event. Gravel Wetland #4 Modeling Info: When demonstrating Q P10 compliance in a hydrologic model, use the following CN and TC below, if the practice used to meet Q P10 is not itself a Tier 1 practice. The CN Adj takes into account the reduction in runoff volume achieved through Tier 1 practices. The T C is calculated by the watershed lag method using CN Adj as CN'. Pre Development TC (min)(Watershed Lag Method)Post Development TC (min) Pre Development TC (min)(Watershed Lag Method)Post Development TC (min) The extreme standard has not been fully met. Provide additional STPs to ensure post development peak runoff does not exceed pre development peak runoff for the 100 yr, 24 hour storm event. Gravel Wetland #4 Modeling Info: When demonstrating Q P100 compliance in a hydrologic model, use the following CN and T C below, if the practice used to meet Q P100 is not a Tier 1 practice. The CNAdj takes into account the reduction in runoff volume achieved through runoff reduction practices. The T C is calculated by the watershed lag method using CN Adj as CN'. Yes No Yes No Last Updated 8/28/2018 SN6: Page 13 of 29 Vermont Operational Stormwater Permit - Standards Compliance Workbook General Discharge Point Information Project name Discharge point serial number (e.g. S/N 001) Name of receiving water Latitude (decimal degrees to five decimal places) Longitude (decimal degrees to five decimal places) Precipitation Data NOAA Atlas 14 Storm WQ Storm 1 yr, 24 hr 10 yr, 24 hr 100 yr, 24 hr Precipitation (inches)1.00 1.90 3.25 4.85 Drainage Area Information Landuse A B C D Total Grass 0.000 0.000 0.000 0.000 0.000 Meadow 0.000 0.000 0.000 11.550 11.550 Woods 0.000 0.000 0.000 3.910 3.910 Existing Impervious 0.000 0.000 0.000 0.060 0.060 Impervious previously authorized under 2002 VSMM (not included in calculations)0.000 Total Pre Site Area 15.520 % Landuse A B C D Total Grass 0.000 0.000 0.000 11.540 11.540 Meadow 0.000 0.000 0.000 0.000 0.000 Woods 0.000 0.000 0.000 0.000 0.000 New Impervious 0.000 0.000 0.000 3.980 3.980 25.6% Existing for Permit Coverage (Treated to New Standards) 0.000 0.000 0.000 0.000 0.000 0.0% Existing Impervious Not for Permit Coverage 0.000 0.0% Redeveloped Impervious 0.000 0.0% 0.000 Total Site Area 15.520 Total Impervious for Permit Coverage 3.980 Net Reduced Impervious 0.000 0.0% Reduced Existing Impervious (for redevelopment)0.060 100.0% Average Catchment Slope, Y (%) Hydraulic Length, l (ft) Pre Development 7.31 1490.00 Post Development 7.31 1490.00 EASTVIEW S/N 007 Wetlands in Potash Brook Watershed 44.45584 -73.15221 * Preciptation values shall be obtained from Pre Development Land Use (acres) Post Development Land Use (acres) Impervious previously authorized under 2002 VSMM Information for Calculating TC by the Watershed Lag Method Last Updated 8/28/2018 SN7: Page 14 of 29 Vermont Operational Stormwater Permit - Standards Compliance Workbook Runoff Calculations 1 yr, 24-hr 10 yr, 24-hr 100 yr, 24-hr 0.5505 1.6826 3.3249 1.0389 2.3860 4.1866 Tier 1/Runoff Reduction Practices Practice TV (ac-ft)TV (ac-ft) Runoff Reduction Calculations Standard Re WQ CP QP10 QP100 TV Required (ac-ft)0.0000 0.3632 0.4884 0.7034 0.8617 TV Provided (ac-ft)0.0000 0.0000 0.0000 0.0000 0.0000 TV Remaining (ac-ft)0.0000 0.3632 0.4884 0.7034 0.8617 Standard met with HCM?n/a No No No No Post-Development CN n/a 89 87 86 85 CNadj n/a 89 87 86 85 Pre-Development CN n/a n/a 78 78 78 Groundwater Recharge Standard (Re)2 Standard Applicable? ReV 0.0000 Standard met with Tier 1 Practices?n/a Recharge Notes: HSG D Soils Predevelopment runoff volume (ac-ft) Pre-routed, post development runoff volume (ac-ft) List all Tier 1 practices below with the associated treatment volume (T V ). The TV will be applied to all treatment standards, except for Green Roofs, which do not receive recharge or water quality credit. Please include the appropriate STP worksheet(s) with the application. Practice Reason recharge not required (if No is selected):Yes No Last Updated 8/28/2018 SN7: Page 15 of 29 Vermont Operational Stormwater Permit - Standards Compliance Workbook Water Quality Treatment Standard (WQ)1 1 (ac-ft)Apply Reduction? WQV - New & Existing 0.3632 0.0% WQV - Redevelopment 0.0000 100.0%Max 25% applied Total WQV 0.3632 WQV met with Tier 1 practices 0.0000 1 WQV to be met with Tier 2 and/or Tier 3 practices 0.3632 WQV Provided (ac-ft)Tier 0.3632 Tier 2 Total WQV Provided (ac-ft)0.3632 ac-ft Is the WQV Standard met?Yes Water Quality Notes: Channel Protection Standard (CP)2 1 Standard Applicable? Standard Met with HCM?No Provide Extended Detention for:1.039 ac-ft Warm or Cold Water Fishery?→Provide: FALSE Extended Detention STP: CNAdj 87 13.0 (Watershed Lag Method) Channel Protection Notes: % Net Reduction % Removed Existing Impervious (Redevelopment) Is all impervious treated by disconnection? NOTE: Please include a copy of the appropriate STP worksheet(s) with the application. Tier 2 & 3 Water Quality Practice Gravel Wetland The channel protection standard has not been fully met. Either increase Tv credit to fully meet HCM or provide extended detention. 24 hours of extended detention See the Vermont Water Quality Standards for warm and cold water designations OR The Alternative Extended Detention Method (§2.2.5.4) is being used. Gravel Wetland #5 Modeling Info: When demonstrating CP compliance with extended detention in a hydrologic model, use the CN and T C below if the practice being modelled is not a Tier 1 practice. The CN Adj takes into account the reduction in runoff volume achieved through Tier 1 practices. The T C is calculated by the watershed lag method using CN Adj as CN'. Post Development TC (min) Yes No ColdWarm No Yes (WQv met) No Yes No Yes Last Updated 8/28/2018 SN7: Page 16 of 29 Vermont Operational Stormwater Permit - Standards Compliance Workbook Overbank Flood Protection (QP10)1 Standard Applicable? Standard Met with HCM?No STP used: Pre-development peak discharge rate (cfs)23.99 Pre-routed, post-development peak discharge rate (cfs)39.77 Routed, post-development peak discharge rate (cfs)13.45 Pre-Development CN (Flow- weighted composite)78 17.3 CNAdj 86 13.4 Overbank Flood Notes: Extreme Flood Protection (QP100)1 Standard Applicable? Standard Met with HCM?No STP used: Pre-development peak discharge rate (cfs)48.07 Pre-routed, post-development peak discharge rate (cfs)66.81 Routed, post-development peak discharge rate (cfs)45.19 Pre-Development CN (Flow- weighted composite)78 17.3 CNAdj 85 13.7 Extreme Flood Notes: The QP10 standard has not been fully met. Provide additional STPs to ensure post development peak runoff does not exceed pre development peak runoff for the 10 yr, 24 hour storm event. Gravel Wetland #5 Modeling Info: When demonstrating Q P10 compliance in a hydrologic model, use the following CN and TC below, if the practice used to meet Q P10 is not itself a Tier 1 practice. The CN Adj takes into account the reduction in runoff volume achieved through Tier 1 practices. The T C is calculated by the watershed lag method using CN Adj as CN'. Pre Development TC (min)(Watershed Lag Method)Post Development TC (min) Pre Development TC (min)(Watershed Lag Method)Post Development TC (min) The extreme standard has not been fully met. Provide additional STPs to ensure post development peak runoff does not exceed pre development peak runoff for the 100 yr, 24 hour storm event. Gravel Wetland #5 Modeling Info: When demonstrating Q P100 compliance in a hydrologic model, use the following CN and T C below, if the practice used to meet Q P100 is not a Tier 1 practice. The CNAdj takes into account the reduction in runoff volume achieved through runoff reduction practices. The T C is calculated by the watershed lag method using CN Adj as CN'. Yes No Yes No Last Updated 8/28/2018 SN7: Page 17 of 29 Vermont Operational Stormwater Permit - Standards Compliance Workbook General Discharge Point Information Project name Discharge point serial number (e.g. S/N 001) Name of receiving water Latitude (decimal degrees to five decimal places) Longitude (decimal degrees to five decimal places) Precipitation Data NOAA Atlas 14 Storm WQ Storm 1 yr, 24 hr 10 yr, 24 hr 100 yr, 24 hr Precipitation (inches)1.00 1.90 3.25 4.85 Drainage Area Information Landuse A B C D Total Grass 0.000 0.000 0.000 0.000 0.000 Meadow 0.000 0.000 0.000 0.000 0.000 Woods 0.000 0.000 0.000 9.190 9.190 Existing Impervious 0.000 0.000 0.000 0.000 0.000 Impervious previously authorized under 2002 VSMM (not included in calculations)0.000 Total Pre Site Area 9.190 % Landuse A B C D Total Grass 0.000 0.000 0.000 4.800 4.800 Meadow 0.000 0.000 0.000 0.000 0.000 Woods 0.000 0.000 0.000 0.000 0.000 New Impervious 0.000 0.000 0.000 4.390 4.390 47.8% Existing for Permit Coverage (Treated to New Standards) 0.000 0.000 0.000 0.000 0.000 0.0% Existing Impervious Not for Permit Coverage 0.000 0.0% Redeveloped Impervious 0.000 0.0% 0.000 Total Site Area 9.190 Total Impervious for Permit Coverage 4.390 Net Reduced Impervious 0.000 0.0% Reduced Existing Impervious (for redevelopment)0.000 0.0% Average Catchment Slope, Y (%) Hydraulic Length, l (ft) Pre Development 9.35 1250.00 Post Development 9.35 1250.00 EASTVIEW S/N 008 Wetlands in Potash Brook Watershed 44.45650 -73.15097 * Preciptation values shall be obtained from Pre Development Land Use (acres) Post Development Land Use (acres) Impervious previously authorized under 2002 VSMM Information for Calculating TC by the Watershed Lag Method Last Updated 8/28/2018 SN8: Page 18 of 29 Vermont Operational Stormwater Permit - Standards Compliance Workbook Runoff Calculations 1 yr, 24-hr 10 yr, 24-hr 100 yr, 24-hr 0.3029 0.9555 1.9131 0.8139 1.6800 2.7927 Tier 1/Runoff Reduction Practices Practice TV (ac-ft)TV (ac-ft) Runoff Reduction Calculations Standard Re WQ CP QP10 QP100 TV Required (ac-ft)0.0000 0.3675 0.5110 0.7245 0.8796 TV Provided (ac-ft)0.0000 0.0000 0.0000 0.0000 0.0000 TV Remaining (ac-ft)0.0000 0.3675 0.5110 0.7245 0.8796 Standard met with HCM?n/a No No No No Post-Development CN n/a 94 91 90 89 CNadj n/a 94 91 90 89 Pre-Development CN n/a n/a 77 77 77 Groundwater Recharge Standard (Re)1 Standard Applicable? ReV 0.0000 Standard met with Tier 1 Practices?n/a Recharge Notes: Predevelopment runoff volume (ac-ft) Pre-routed, post development runoff volume (ac-ft) List all Tier 1 practices below with the associated treatment volume (T V ). The TV will be applied to all treatment standards, except for Green Roofs, which do not receive recharge or water quality credit. Please include the appropriate STP worksheet(s) with the application. Practice Yes No Last Updated 8/28/2018 SN8: Page 19 of 29 Vermont Operational Stormwater Permit - Standards Compliance Workbook Water Quality Treatment Standard (WQ)1 1 (ac-ft)Apply Reduction? WQV - New & Existing 0.3675 0.0% WQV - Redevelopment 0.0000 0.0% Total WQV 0.3675 WQV met with Tier 1 practices 0.0000 1 WQV to be met with Tier 2 and/or Tier 3 practices 0.3675 WQV Provided (ac-ft)Tier 0.3675 Tier 2 Total WQV Provided (ac-ft)0.3675 ac-ft Is the WQV Standard met?Yes Water Quality Notes: Channel Protection Standard (CP)2 1 Standard Applicable? Standard Met with HCM?No Provide Extended Detention for:0.814 ac-ft Warm or Cold Water Fishery?→Provide: FALSE Extended Detention STP: CNAdj 91 8.4 (Watershed Lag Method) Channel Protection Notes: % Net Reduction % Removed Existing Impervious (Redevelopment) Is all impervious treated by disconnection? NOTE: Please include a copy of the appropriate STP worksheet(s) with the application. Tier 2 & 3 Water Quality Practice Gravel Wetland The channel protection standard has not been fully met. Either increase Tv credit to fully meet HCM or provide extended detention. 24 hours of extended detention See the Vermont Water Quality Standards for warm and cold water designations OR The Alternative Extended Detention Method (§2.2.5.4) is being used. Gravel Wetlands 6A and 6B Modeling Info: When demonstrating CP compliance with extended detention in a hydrologic model, use the CN and T C below if the practice being modelled is not a Tier 1 practice. The CN Adj takes into account the reduction in runoff volume achieved through Tier 1 practices. The T C is calculated by the watershed lag method using CN Adj as CN'. Post Development TC (min) Yes No ColdWarm No Yes (WQv met) No Yes No Yes Last Updated 8/28/2018 SN8: Page 20 of 29 Vermont Operational Stormwater Permit - Standards Compliance Workbook Overbank Flood Protection (QP10)1 Standard Applicable? Standard Met with HCM?No STP used: Pre-development peak discharge rate (cfs)15.27 Pre-routed, post-development peak discharge rate (cfs)32.51 Routed, post-development peak discharge rate (cfs)11.50 Pre-Development CN (Flow- weighted composite)77 13.6 CNAdj 90 8.8 Overbank Flood Notes: Extreme Flood Protection (QP100)1 Standard Applicable? Standard Met with HCM?No STP used: Pre-development peak discharge rate (cfs)31.87 Pre-routed, post-development peak discharge rate (cfs)52.47 Routed, post-development peak discharge rate (cfs)22.05 Pre-Development CN (Flow- weighted composite)77 13.6 CNAdj 89 9.0 Extreme Flood Notes: The QP10 standard has not been fully met. Provide additional STPs to ensure post development peak runoff does not exceed pre development peak runoff for the 10 yr, 24 hour storm event. Gravel Wetlands 6A and 6B Modeling Info: When demonstrating Q P10 compliance in a hydrologic model, use the following CN and TC below, if the practice used to meet Q P10 is not itself a Tier 1 practice. The CN Adj takes into account the reduction in runoff volume achieved through Tier 1 practices. The T C is calculated by the watershed lag method using CN Adj as CN'. Pre Development TC (min)(Watershed Lag Method)Post Development TC (min) Pre Development TC (min)(Watershed Lag Method)Post Development TC (min) The extreme standard has not been fully met. Provide additional STPs to ensure post development peak runoff does not exceed pre development peak runoff for the 100 yr, 24 hour storm event. Gravel Wetlands #6A and #6B Modeling Info: When demonstrating Q P100 compliance in a hydrologic model, use the following CN and T C below, if the practice used to meet Q P100 is not a Tier 1 practice. The CNAdj takes into account the reduction in runoff volume achieved through runoff reduction practices. The T C is calculated by the watershed lag method using CN Adj as CN'. Yes No Yes No Last Updated 8/28/2018 SN8: Page 21 of 29 Vermont Operational Stormwater Permit - Standards Compliance Workbook General Discharge Point Information Project name Discharge point serial number (e.g. S/N 001) Name of receiving water Latitude (decimal degrees to five decimal places) Longitude (decimal degrees to five decimal places) Precipitation Data NOAA Atlas 14 Storm WQ Storm 1 yr, 24 hr 10 yr, 24 hr 100 yr, 24 hr Precipitation (inches)1.00 1.90 3.25 4.85 Drainage Area Information Landuse A B C D Total Grass 0.000 0.000 0.000 0.000 0.000 Meadow 0.000 0.000 0.000 0.000 0.000 Woods 0.000 0.000 0.000 4.090 4.090 Existing Impervious 0.000 0.000 0.000 0.000 0.000 Impervious previously authorized under 2002 VSMM (not included in calculations)0.000 Total Pre Site Area 4.090 % Landuse A B C D Total Grass 0.000 0.000 0.000 3.390 3.390 Meadow 0.000 0.000 0.000 0.000 0.000 Woods 0.000 0.000 0.000 0.000 0.000 New Impervious 0.000 0.000 0.000 0.700 0.700 17.1% Existing for Permit Coverage (Treated to New Standards) 0.000 0.000 0.000 0.000 0.000 0.0% Existing Impervious Not for Permit Coverage 0.000 0.0% Redeveloped Impervious 0.000 0.0% 0.000 Total Site Area 4.090 Total Impervious for Permit Coverage 0.700 Net Reduced Impervious 0.000 0.0% Reduced Existing Impervious (for redevelopment)0.000 0.0% Average Catchment Slope, Y (%) Hydraulic Length, l (ft) Pre Development 8.62 680.00 Post Development 8.62 680.00 EASTVIEW S/N 009 Wetlands in Potash Brook Watershed 44.45452 -73.14914 * Preciptation values shall be obtained from Pre Development Land Use (acres) Post Development Land Use (acres) Impervious previously authorized under 2002 VSMM Information for Calculating TC by the Watershed Lag Method Last Updated 8/28/2018 SN9: Page 22 of 29 Vermont Operational Stormwater Permit - Standards Compliance Workbook Runoff Calculations 1 yr, 24-hr 10 yr, 24-hr 100 yr, 24-hr 0.1348 0.4252 0.8514 0.2397 0.5829 1.0495 Tier 1/Runoff Reduction Practices Practice TV (ac-ft)TV (ac-ft) Runoff Reduction Calculations Standard Re WQ CP QP10 QP100 TV Required (ac-ft)0.0000 0.0695 0.1049 0.1577 0.1981 TV Provided (ac-ft)0.0000 0.0000 0.0000 0.0000 0.0000 TV Remaining (ac-ft)0.0000 0.0695 0.1049 0.1577 0.1981 Standard met with HCM?n/a No No No No Post-Development CN n/a 86 85 84 83 CNadj n/a 86 85 84 83 Pre-Development CN n/a n/a 77 77 77 Groundwater Recharge Standard (Re)2 Standard Applicable? ReV 0.0000 Standard met with Tier 1 Practices?n/a Recharge Notes: HSG D Soils Predevelopment runoff volume (ac-ft) Pre-routed, post development runoff volume (ac-ft) List all Tier 1 practices below with the associated treatment volume (T V ). The TV will be applied to all treatment standards, except for Green Roofs, which do not receive recharge or water quality credit. Please include the appropriate STP worksheet(s) with the application. Practice Reason recharge not required (if No is selected):Yes No Last Updated 8/28/2018 SN9: Page 23 of 29 Vermont Operational Stormwater Permit - Standards Compliance Workbook Water Quality Treatment Standard (WQ)1 1 (ac-ft)Apply Reduction? WQV - New & Existing 0.0695 0.0% WQV - Redevelopment 0.0000 0.0% Total WQV 0.0695 WQV met with Tier 1 practices 0.0000 1 WQV to be met with Tier 2 and/or Tier 3 practices 0.0695 WQV Provided (ac-ft)Tier 0.0695 Total WQV Provided (ac-ft)0.0695 ac-ft Is the WQV Standard met?Yes Water Quality Notes: Channel Protection Standard (CP)2 1 Standard Applicable? Standard Met with HCM?No Provide Extended Detention for:0.240 ac-ft Warm or Cold Water Fishery?→Provide: FALSE Extended Detention STP: CNAdj 85 6.8 (Watershed Lag Method) Channel Protection Notes: % Net Reduction % Removed Existing Impervious (Redevelopment) Is all impervious treated by disconnection? Tier 2 & 3 Water Quality Practice The channel protection standard has not been fully met. Either increase Tv credit to fully meet HCM or provide extended detention. 24 hours of extended detention See the Vermont Water Quality Standards for warm and cold water designations OR The Alternative Extended Detention Method (§2.2.5.4) is being used. Gravel Wetland #7 Modeling Info: When demonstrating CP compliance with extended detention in a hydrologic model, use the CN and T C below if the practice being modelled is not a Tier 1 practice. The CN Adj takes into account the reduction in runoff volume achieved through Tier 1 practices. The T C is calculated by the watershed lag method using CN Adj as CN'. Post Development TC (min) Yes No ColdWarm No Yes (WQv met) No Yes No Yes Last Updated 8/28/2018 SN9: Page 24 of 29 Vermont Operational Stormwater Permit - Standards Compliance Workbook Overbank Flood Protection (QP10)1 Standard Applicable? Standard Met with HCM?No STP used: Pre-development peak discharge rate (cfs)8.09 Pre-routed, post-development peak discharge rate (cfs)12.69 Routed, post-development peak discharge rate (cfs)0.73 Pre-Development CN (Flow- weighted composite)77 8.7 CNAdj 84 7.0 Overbank Flood Notes: Extreme Flood Protection (QP100)1 Standard Applicable? Standard Met with HCM?No STP used: Pre-development peak discharge rate (cfs)16.28 Pre-routed, post-development peak discharge rate (cfs)22.24 Routed, post-development peak discharge rate (cfs)1.24 Pre-Development CN (Flow- weighted composite)77 8.7 CNAdj 83 7.1 Extreme Flood Notes: The QP10 standard has not been fully met. Provide additional STPs to ensure post development peak runoff does not exceed pre development peak runoff for the 10 yr, 24 hour storm event. Gravel Wetland #7 Modeling Info: When demonstrating Q P10 compliance in a hydrologic model, use the following CN and TC below, if the practice used to meet Q P10 is not itself a Tier 1 practice. The CN Adj takes into account the reduction in runoff volume achieved through Tier 1 practices. The T C is calculated by the watershed lag method using CN Adj as CN'. Pre Development TC (min)(Watershed Lag Method)Post Development TC (min) Pre Development TC (min)(Watershed Lag Method)Post Development TC (min) The extreme standard has not been fully met. Provide additional STPs to ensure post development peak runoff does not exceed pre development peak runoff for the 100 yr, 24 hour storm event. Gravel Wetland #7 Modeling Info: When demonstrating Q P100 compliance in a hydrologic model, use the following CN and T C below, if the practice used to meet Q P100 is not a Tier 1 practice. The CNAdj takes into account the reduction in runoff volume achieved through runoff reduction practices. The T C is calculated by the watershed lag method using CN Adj as CN'. Yes No Yes No Last Updated 8/28/2018 SN9: Page 25 of 29 Vermont Operational Stormwater Permit - Standards Compliance Workbook General Discharge Point Information Project name Discharge point serial number (e.g. S/N 001) Name of receiving water Latitude (decimal degrees to five decimal places) Longitude (decimal degrees to five decimal places) Precipitation Data NOAA Atlas 14 Storm WQ Storm 1 yr, 24 hr 10 yr, 24 hr 100 yr, 24 hr Precipitation (inches)1.00 1.90 3.25 4.85 Drainage Area Information Landuse A B C D Total Grass 0.000 0.000 0.000 0.000 0.000 Meadow 0.000 0.000 0.000 0.000 0.000 Woods 0.000 0.000 0.000 12.700 12.700 Existing Impervious 0.000 0.000 0.000 0.000 0.000 Impervious previously authorized under 2002 VSMM (not included in calculations)0.000 Total Pre Site Area 12.700 % Landuse A B C D Total Grass 0.000 0.000 0.000 11.700 11.700 Meadow 0.000 0.000 0.000 0.000 0.000 Woods 0.000 0.000 0.000 0.000 0.000 New Impervious 0.000 0.000 0.000 1.000 1.000 7.9% Existing for Permit Coverage (Treated to New Standards) 0.000 0.000 0.000 0.000 0.000 0.0% Existing Impervious Not for Permit Coverage 0.000 0.0% Redeveloped Impervious 0.000 0.0% 0.000 Total Site Area 12.700 Total Impervious for Permit Coverage 1.000 Net Reduced Impervious 0.000 0.0% Reduced Existing Impervious (for redevelopment)0.000 0.0% Average Catchment Slope, Y (%) Hydraulic Length, l (ft) Pre Development 5.2 960.00 Post Development 5.2 960.00 EASTVIEW S/N 010 Potash Brook 44.45358 -73.14810 * Preciptation values shall be obtained from Pre Development Land Use (acres) Post Development Land Use (acres) Impervious previously authorized under 2002 VSMM Information for Calculating TC by the Watershed Lag Method Last Updated 8/28/2018 SN10: Page 26 of 29 Vermont Operational Stormwater Permit - Standards Compliance Workbook Runoff Calculations 1 yr, 24-hr 10 yr, 24-hr 100 yr, 24-hr 0.4186 1.3204 2.6437 0.6296 1.6559 3.0778 Tier 1/Runoff Reduction Practices Practice TV (ac-ft)TV (ac-ft) Runoff Reduction Calculations Standard Re WQ CP QP10 QP100 TV Required (ac-ft)0.0000 0.1279 0.2110 0.3355 0.4341 TV Provided (ac-ft)0.0000 0.0000 0.0000 0.0000 0.0000 TV Remaining (ac-ft)0.0000 0.1279 0.2110 0.3355 0.4341 Standard met with HCM?n/a No No No No Post-Development CN n/a 82 82 82 82 CNadj n/a 82 82 82 82 Pre-Development CN n/a n/a 77 77 77 Groundwater Recharge Standard (Re)2 Standard Applicable? ReV 0.0000 Standard met with Tier 1 Practices?n/a Recharge Notes: HSG D Soils Predevelopment runoff volume (ac-ft) Pre-routed, post development runoff volume (ac-ft) List all Tier 1 practices below with the associated treatment volume (T V ). The TV will be applied to all treatment standards, except for Green Roofs, which do not receive recharge or water quality credit. Please include the appropriate STP worksheet(s) with the application. Practice Reason recharge not required (if No is selected):Yes No Last Updated 8/28/2018 SN10: Page 27 of 29 Vermont Operational Stormwater Permit - Standards Compliance Workbook Water Quality Treatment Standard (WQ)1 1 (ac-ft)Apply Reduction? WQV - New & Existing 0.1279 0.0% WQV - Redevelopment 0.0000 0.0% Total WQV 0.1279 WQV met with Tier 1 practices 0.0000 1 WQV to be met with Tier 2 and/or Tier 3 practices 0.1279 WQV Provided (ac-ft)Tier 0.1279 Tier 2 Total WQV Provided (ac-ft)0.1279 ac-ft Is the WQV Standard met?Yes Water Quality Notes: Channel Protection Standard (CP)2 1 Standard Applicable? Standard Met with HCM?No Provide Extended Detention for:0.630 ac-ft Warm or Cold Water Fishery?→Provide: FALSE Extended Detention STP: CNAdj 82 12.5 (Watershed Lag Method) Channel Protection Notes: % Net Reduction % Removed Existing Impervious (Redevelopment) Is all impervious treated by disconnection? NOTE: Please include a copy of the appropriate STP worksheet(s) with the application. Tier 2 & 3 Water Quality Practice Gravel Wetland The channel protection standard has not been fully met. Either increase Tv credit to fully meet HCM or provide extended detention. 24 hours of extended detention See the Vermont Water Quality Standards for warm and cold water designations OR The Alternative Extended Detention Method (§2.2.5.4) is being used. Gravel Wetland #8 Modeling Info: When demonstrating CP compliance with extended detention in a hydrologic model, use the CN and T C below if the practice being modelled is not a Tier 1 practice. The CN Adj takes into account the reduction in runoff volume achieved through Tier 1 practices. The T C is calculated by the watershed lag method using CN Adj as CN'. Post Development TC (min) Yes No ColdWarm No Yes (WQv met) No Yes No Yes Last Updated 8/28/2018 SN10: Page 28 of 29 Vermont Operational Stormwater Permit - Standards Compliance Workbook Overbank Flood Protection (QP10)1 Standard Applicable? Standard Met with HCM?No STP used: Pre-development peak discharge rate (cfs)20.09 Pre-routed, post-development peak discharge rate (cfs)28.07 Routed, post-development peak discharge rate (cfs)5.00 Pre-Development CN (Flow- weighted composite)77 14.8 CNAdj 82 12.7 Overbank Flood Notes: Extreme Flood Protection (QP100)1 Standard Applicable? Standard Met with HCM?No STP used: Pre-development peak discharge rate (cfs)41.01 Pre-routed, post-development peak discharge rate (cfs)51.90 Routed, post-development peak discharge rate (cfs)28.98 Pre-Development CN (Flow- weighted composite)77 14.8 CNAdj 82 12.8 Extreme Flood Notes: The QP10 standard has not been fully met. Provide additional STPs to ensure post development peak runoff does not exceed pre development peak runoff for the 10 yr, 24 hour storm event. Gravel Wetland #8 Modeling Info: When demonstrating Q P10 compliance in a hydrologic model, use the following CN and TC below, if the practice used to meet Q P10 is not itself a Tier 1 practice. The CN Adj takes into account the reduction in runoff volume achieved through Tier 1 practices. The T C is calculated by the watershed lag method using CN Adj as CN'. Pre Development TC (min)(Watershed Lag Method)Post Development TC (min) Pre Development TC (min)(Watershed Lag Method)Post Development TC (min) The extreme standard has not been fully met. Provide additional STPs to ensure post development peak runoff does not exceed pre development peak runoff for the 100 yr, 24 hour storm event. Gravel Wetland #8 Modeling Info: When demonstrating Q P100 compliance in a hydrologic model, use the following CN and T C below, if the practice used to meet Q P100 is not a Tier 1 practice. The CNAdj takes into account the reduction in runoff volume achieved through runoff reduction practices. The T C is calculated by the watershed lag method using CN Adj as CN'. Yes No Yes No Last Updated 8/28/2018 SN10: Page 29 of 29 Version: 1/29/2018 Project Name:Hillside @ O'Brien Farm Eastview Discharge Point: Treatment Wetland # Practice Drainage Area For Permit Coverage Not for Permit Coverage Total to Practice 1 Total Area (acres)6.550 0.000 6.550 2 3.750 0.000 3.750 3 0.000 0.000 0.000 WQV for credit WQV not for credit Total WQV 4 WQV to practice 0.3085 0.0000 0.3085 95 5 2 6 2 Response Attachment location 7 8 9 10 11* 12* 13* Response Attachment location 14 Forebay Has a low for orifice been provided to meet the the WQV and CPV extended Has a liner designed in accordance with Section 4.3.5.2 been provided if the infiltration rate exceed 0.05 inches per hour and the wetland is located above Pre-Treatment (4.3.6.3) Has pretreatment been provided for non-rooftop runoff? New Impervious (acres) 4 3Treatment Wetlands (4.3.5) Redeveloped Impervious Discharges to Cold or Warm Water Fishery? Modified CN for WQ (1.0") storm Note: Designers may use the Practice Drainage Area Runoff Calculator (second tab) for calculation of practice- specific runoff volumes for other treatment standards. Conveyance (4.3.5.2) Are inlets stabilized to ensure that non-erosive conditions exist for at least the 1-year, 24 hour storm? * Questions preceded by an asterix (*) may change based on previously entered values Have inlet pipes been set at the permanent pool or the base of the gravel bed? ↑Enter this value on the Standards Compliance Workbook Is outlet elevation designed such that a sub-surface water level is maintained in the gravel wetland? If the gravel wetland is designed with an organic soil layer at the surface, have vertical perforated riser pipes been provided to deliver stormwater stormwater from the surface down to the gravel bed? Have the outfalls and the conveyance to the discharge point been designed and protected to avoid erosion? Practice Type Yes No Yes No No No Yes Yes NoYes Cold Warm NoYes NoYes NoYes Shallow surface wetland Gravel wetland Page 1 of 4 15 Response Attachment location 16 ft3 1378 17 ft3 6891 18 ft3 8269 19* 20* 21 61.5%Yes 22 23 Response Attachment location 24 25 26 27 28 29 Does the planting plan specify that no woody vegetation >2 inches in diameter shall be planted or allowed to grow on the dam, within 15 feet of the dam or the toe of the embankment, or within 25 of a principal spillway outlet? What type of pretreatment is being used? Has an aquatic been been provided that extends at least 5 feet inward from the normal water edge and is no more than 18 inches deep? Has a setback been provided that extends 25 feet from the maximum design water surface elevation of the practice? Are all deep pool areas of ≥ 4 feet depth with side slopes steeper than 4:1 (H:V) surrounded by a safety bench with ≤6% slope extending 10 feet outward from the normal water edge to the toe of the side slope? Landscaping (4.3.6.5) Treatment (4.3.6.4) Has a minimum flow path at normal water level of 3:1 been provided? Attachment location: Indicate the specific location (i.e. appendix, page, plan sheet) where the requisite support documentation has been provided within the application. What is the volume stored in the forebay or other volumetric pre- treatment if used? (minimum 10% WQV) What is the volume stored in the permanent pool? What is the total WQV stored at the normal water level (pre- treatment + permanent pool)? Does the pre-treatment volume plus the permanent pool equal at least 50% of the WQV? Has a planting plan been prepared showing how aquatic and terrestrial areas will be stabilized, including plant species, plant locations, sources of plant material and any required soil amendments? Are any donor organic soils used in the practice obtained from a source other than natural wetlands? Is the remaining WQV provided for by extended detention over 24 hours? Swale Filter Strip Forebay (10% WQv) Deep Sump Catch Basins Proprietary NoYes NoYes NoYes Yes No NoYes NoYes NoYes NoYes NoYes NoYes Page 2 of 4 Practice Drainage Area Runoff Calculator Project Name: Discharge Point: Treatment Wetland # Precipitation Data NOAA Atlas 14 Storm WQ Storm 1 yr, 24 hr 10 yr, 24 hr 100 yr, 24 hr Precipitation (inches)1.00 1.90 3.25 4.85 Drainage Area Information Landuse A B C D Grass 0.000 0.000 0.000 0.000 0.000 Meadow 0.000 0.000 0.000 0.000 0.000 Woods 0.000 0.000 0.000 6.270 6.270 Pavement, roofs, and other impervious 0.000 0.000 0.000 0.280 0.280 Total 0.000 0.000 0.000 6.550 6.550 Landuse A B C D Grass 0.000 0.000 0.000 2.800 2.800 Meadow 0.000 0.000 0.000 0.000 0.000 Woods 0.000 0.000 0.000 0.000 0.000 Pavement, roofs, and other impervious 0.000 0.000 0.000 3.750 3.750 Total 0.000 0.000 0.000 6.550 6.550 TV of upstream practices:0.000 ac-ft TV credit of this practice:0.000 ac-ft Treatment Standard Required Treatment Volume Post Development Runoff Volume Pre- development Runoff Volume Post Composite CN (to practice) CNAdj (with TV practice credit) Pre Composite CN Channel Protection (Hydrologic Condition Method) 0.3950 0.6408 0.2458 92 92 79 Overbank Flood 0.5567 1.2790 0.7223 91 91 78 Extreme Flood 0.6734 2.0863 1.4129 91 91 78 Information for Calculating TC by the Watershed Lag Method 1 yr 10 yr 100 yr Time of Concentration, TC (min)Hydraulic Length, l (ft) Average Catchment Slope, Y (%) Eastview 4 3 Hydrologic Soil Group Total (acres) This tool may be used to calculate the required treatment volumes for the area draining to an individual practice where the practices drainage area is only a portion of of the area draining to a discharge point. Where the practice receives runoff from the entire area to a discharge point, this calculator will give the same information as the Standards Compliance Workbook. * Preciptation values shall be obtained from Pre Development Land Use (acres) Hydrologic Soil Group Total (acres) Post Development Land Use (acres) Pre Development 6.12%1500.00 18.6 18.8 18.9 Post Development, upstream of practice 6.12%1500.00 11.3 11.8 12.0 Post Development, with TV credit from practice 0.00%0.00 0.0 0.0 0.0 Version: 1/29/2018 Project Name:Hillside @ O'Brien Farm Phase2 Discharge Point: Treatment Wetland # Practice Drainage Area For Permit Coverage Not for Permit Coverage Total to Practice 1 Total Area (acres)7.080 0.000 7.080 2 3.020 0.000 3.020 3 0.000 0.000 WQV for credit WQV not for credit Total WQV 4 WQV to practice 0.2560 0.0000 0.2560 93 5 2 6 2 Response Attachment location 7 8 9 10 11* 12* 13* Response Attachment location 14 Forebay ↑Enter this value on the Standards Compliance Workbook Is outlet elevation designed such that a sub-surface water level is maintained in the gravel wetland? If the gravel wetland is designed with an organic soil layer at the surface, have vertical perforated riser pipes been provided to deliver stormwater stormwater from the surface down to the gravel bed? Have the outfalls and the conveyance to the discharge point been designed and protected to avoid erosion? Practice Type Discharges to Cold or Warm Water Fishery? Modified CN for WQ (1.0") storm Note: Designers may use the Practice Drainage Area Runoff Calculator (second tab) for calculation of practice- specific runoff volumes for other treatment standards. Conveyance (4.3.5.2) Are inlets stabilized to ensure that non-erosive conditions exist for at least the 1-year, 24 hour storm? * Questions preceded by an asterix (*) may change based on previously entered values Have inlet pipes been set at the permanent pool or the base of the gravel bed? New Impervious (acres) 6 4Treatment Wetlands (4.3.5) Has a low for orifice been provided to meet the the WQV and CPV extended Has a liner designed in accordance with Section 4.3.5.2 been provided if the infiltration rate exceed 0.05 inches per hour and the wetland is located above Redeveloped Impervious Pre-Treatment (4.3.6.3) Has pretreatment been provided for non-rooftop runoff? Yes No Yes No No No Yes Yes NoYes Cold Warm NoYes NoYes NoYes Shallow surface wetland Gravel wetland Page 1 of 4 15 Response Attachment location 16 ft3 1040 17 ft3 4592 18 ft3 5632 19* 20* 21 50.5%Yes 22 23 Response Attachment location 24 25 26 27 28 29 Has a minimum flow path at normal water level of 3:1 been provided? Attachment location: Indicate the specific location (i.e. appendix, page, plan sheet) where the requisite support documentation has been provided within the application. What is the volume stored in the forebay or other volumetric pre- treatment if used? (minimum 10% WQV) What is the volume stored in the permanent pool? What is the total WQV stored at the normal water level (pre- treatment + permanent pool)? Does the pre-treatment volume plus the permanent pool equal at least 50% of the WQV? Has a planting plan been prepared showing how aquatic and terrestrial areas will be stabilized, including plant species, plant locations, sources of plant material and any required soil amendments? Are any donor organic soils used in the practice obtained from a source other than natural wetlands? Is the remaining WQV provided for by extended detention over 24 hours? Treatment (4.3.6.4) Does the planting plan specify that no woody vegetation >2 inches in diameter shall be planted or allowed to grow on the dam, within 15 feet of the dam or the toe of the embankment, or within 25 of a principal spillway outlet? What type of pretreatment is being used? Has an aquatic been been provided that extends at least 5 feet inward from the normal water edge and is no more than 18 inches deep? Has a setback been provided that extends 25 feet from the maximum design water surface elevation of the practice? Are all deep pool areas of ≥ 4 feet depth with side slopes steeper than 4:1 (H:V) surrounded by a safety bench with ≤6% slope extending 10 feet outward from the normal water edge to the toe of the side slope? Landscaping (4.3.6.5) Swale Filter Strip Forebay (10% WQv) Deep Sump Catch Basins Proprietary NoYes NoYes NoYes Yes No NoYes NoYes NoYes NoYes NoYes NoYes Page 2 of 4 Practice Drainage Area Runoff Calculator Project Name: Discharge Point: Treatment Wetland # Precipitation Data NOAA Atlas 14 Storm WQ Storm 1 yr, 24 hr 10 yr, 24 hr 100 yr, 24 hr Precipitation (inches)1.00 1.90 3.25 4.85 Drainage Area Information Landuse A B C D Grass 0.000 0.000 0.000 0.000 0.000 Meadow 0.000 0.000 0.000 4.390 4.390 Woods 0.000 0.000 0.000 2.600 2.600 Pavement, roofs, and other impervious 0.000 0.000 0.000 0.090 0.090 Total 0.000 0.000 0.000 7.080 7.080 Landuse A B C D Grass 0.000 0.000 0.000 4.060 4.060 Meadow 0.000 0.000 0.000 0.000 0.000 Woods 0.000 0.000 0.000 0.000 0.000 Pavement, roofs, and other impervious 0.000 0.000 0.000 3.020 3.020 Total 0.000 0.000 0.000 7.080 7.080 TV of upstream practices:0.000 ac-ft TV credit of this practice:0.000 ac-ft Treatment Standard Required Treatment Volume Post Development Runoff Volume Pre- development Runoff Volume Post Composite CN (to practice) CNAdj (with TV practice credit) Pre Composite CN Channel Protection (Hydrologic Condition Method) 0.3363 0.5916 0.2553 90 90 78 Overbank Flood 0.4745 1.2467 0.7722 89 89 78 Extreme Flood 0.5742 2.0957 1.5215 88 88 78 Information for Calculating TC by the Watershed Lag Method 1 yr 10 yr 100 yr Time of Concentration, TC (min)Hydraulic Length, l (ft) Average Catchment Slope, Y (%) Hillside @ O'Brien Farm East 6 4 Hydrologic Soil Group Total (acres) This tool may be used to calculate the required treatment volumes for the area draining to an individual practice where the practices drainage area is only a portion of of the area draining to a discharge point. Where the practice receives runoff from the entire area to a discharge point, this calculator will give the same information as the Standards Compliance Workbook. * Preciptation values shall be obtained from Pre Development Land Use (acres) Hydrologic Soil Group Total (acres) Post Development Land Use (acres) Pre Development 8.87%1070.00 11.9 12.0 12.0 Post Development, upstream of practice 8.87%1070.00 7.9 8.3 8.5 Post Development, with TV credit from practice 0.00%0.00 0.0 0.0 0.0 Version: 1/29/2018 Project Name:Hillside @ O'Brien Farm Phase2 Discharge Point: Treatment Wetland # Practice Drainage Area For Permit Coverage Not for Permit Coverage Total to Practice 1 Total Area (acres)15.520 0.000 15.520 2 3.980 0.000 3.980 3 0.000 0.000 WQV for credit WQV not for credit Total WQV 4 WQV to practice 0.3632 0.0000 0.3632 89 5 2 6 2 Response Attachment location 7 8 9 10 11* 12* 13* Response Attachment location 14 Forebay ↑Enter this value on the Standards Compliance Workbook Is outlet elevation designed such that a sub-surface water level is maintained in the gravel wetland? If the gravel wetland is designed with an organic soil layer at the surface, have vertical perforated riser pipes been provided to deliver stormwater stormwater from the surface down to the gravel bed? Have the outfalls and the conveyance to the discharge point been designed and protected to avoid erosion? Practice Type Discharges to Cold or Warm Water Fishery? Modified CN for WQ (1.0") storm Note: Designers may use the Practice Drainage Area Runoff Calculator (second tab) for calculation of practice- specific runoff volumes for other treatment standards. Conveyance (4.3.5.2) Are inlets stabilized to ensure that non-erosive conditions exist for at least the 1-year, 24 hour storm? * Questions preceded by an asterix (*) may change based on previously entered values Have inlet pipes been set at the permanent pool or the base of the gravel bed? New Impervious (acres) 7 5Treatment Wetlands (4.3.5) Has a low for orifice been provided to meet the the WQV and CPV extended Has a liner designed in accordance with Section 4.3.5.2 been provided if the infiltration rate exceed 0.05 inches per hour and the wetland is located above Redeveloped Impervious Pre-Treatment (4.3.6.3) Has pretreatment been provided for non-rooftop runoff? Yes No Yes No No No Yes Yes NoYes Cold Warm NoYes NoYes NoYes Shallow surface wetland Gravel wetland Page 1 of 4 15 Response Attachment location 16 ft3 1174 17 ft3 5871 18 ft3 7045 19* 20* 21 44.5%No - revise design 22 23 Response Attachment location 24 25 26 27 28 29 Has a minimum flow path at normal water level of 3:1 been provided? Attachment location: Indicate the specific location (i.e. appendix, page, plan sheet) where the requisite support documentation has been provided within the application. What is the volume stored in the forebay or other volumetric pre- treatment if used? (minimum 10% WQV) What is the volume stored in the permanent pool? What is the total WQV stored at the normal water level (pre- treatment + permanent pool)? Does the pre-treatment volume plus the permanent pool equal at least 50% of the WQV? Has a planting plan been prepared showing how aquatic and terrestrial areas will be stabilized, including plant species, plant locations, sources of plant material and any required soil amendments? Are any donor organic soils used in the practice obtained from a source other than natural wetlands? Is the remaining WQV provided for by extended detention over 24 hours? Treatment (4.3.6.4) Does the planting plan specify that no woody vegetation >2 inches in diameter shall be planted or allowed to grow on the dam, within 15 feet of the dam or the toe of the embankment, or within 25 of a principal spillway outlet? What type of pretreatment is being used? Has an aquatic been been provided that extends at least 5 feet inward from the normal water edge and is no more than 18 inches deep? Has a setback been provided that extends 25 feet from the maximum design water surface elevation of the practice? Are all deep pool areas of ≥ 4 feet depth with side slopes steeper than 4:1 (H:V) surrounded by a safety bench with ≤6% slope extending 10 feet outward from the normal water edge to the toe of the side slope? Landscaping (4.3.6.5) Swale Filter Strip Forebay (10% WQv) Deep Sump Catch Basins Proprietary NoYes NoYes NoYes Yes No NoYes NoYes NoYes NoYes NoYes NoYes Page 2 of 4 Practice Drainage Area Runoff Calculator Project Name: Discharge Point: Treatment Wetland # Precipitation Data NOAA Atlas 14 Storm WQ Storm 1 yr, 24 hr 10 yr, 24 hr 100 yr, 24 hr Precipitation (inches)1.00 1.90 3.25 4.85 Drainage Area Information Landuse A B C D Grass 0.000 0.000 0.000 0.000 0.000 Meadow 0.000 0.000 0.000 11.550 11.550 Woods 0.000 0.000 0.000 3.910 3.910 Pavement, roofs, and other impervious 0.000 0.000 0.000 0.060 0.060 Total 0.000 0.000 0.000 15.520 15.520 Landuse A B C D Grass 0.000 0.000 0.000 11.540 11.540 Meadow 0.000 0.000 0.000 0.000 0.000 Woods 0.000 0.000 0.000 0.000 0.000 Pavement, roofs, and other impervious 0.000 0.000 0.000 3.980 3.980 Total 0.000 0.000 0.000 15.520 15.520 TV of upstream practices:0.000 ac-ft TV credit of this practice:0.000 ac-ft Treatment Standard Required Treatment Volume Post Development Runoff Volume Pre- development Runoff Volume Post Composite CN (to practice) CNAdj (with TV practice credit) Pre Composite CN Channel Protection (Hydrologic Condition Method) 0.4884 1.0389 0.5505 87 87 78 Overbank Flood 0.7034 2.3860 1.6826 86 86 78 Extreme Flood 0.8617 4.1866 3.3249 85 85 78 Information for Calculating TC by the Watershed Lag Method 1 yr 10 yr 100 yr Time of Concentration, TC (min)Hydraulic Length, l (ft) Average Catchment Slope, Y (%) Eastview 7 5 Hydrologic Soil Group Total (acres) This tool may be used to calculate the required treatment volumes for the area draining to an individual practice where the practices drainage area is only a portion of of the area draining to a discharge point. Where the practice receives runoff from the entire area to a discharge point, this calculator will give the same information as the Standards Compliance Workbook. * Preciptation values shall be obtained from Pre Development Land Use (acres) Hydrologic Soil Group Total (acres) Post Development Land Use (acres) Pre Development 7.31%1490.00 17.2 17.3 17.3 Post Development, upstream of practice 7.31%1490.00 13.0 13.4 13.7 Post Development, with TV credit from practice 0.00%0.00 0.0 0.0 0.0 Version: 1/29/2018 Project Name:Hillside @ O'Brien Farm Phase2 Discharge Point: Treatment Wetland # Practice Drainage Area For Permit Coverage Not for Permit Coverage Total to Practice 1 Total Area (acres)3.880 0.000 3.880 2 2.050 0.000 2.050 3 0.000 0.000 WQV for credit WQV not for credit Total WQV 4 WQV to practice 0.1699 0.0000 0.1699 94 5 2 6 2 Response Attachment location 7 8 9 10 11* 12* 13* Response Attachment location 14 Forebay Has a low for orifice been provided to meet the the WQV and CPV extended Has a liner designed in accordance with Section 4.3.5.2 been provided if the infiltration rate exceed 0.05 inches per hour and the wetland is located above Pre-Treatment (4.3.6.3) Has pretreatment been provided for non-rooftop runoff? New Impervious (acres) 8 6ATreatment Wetlands (4.3.5) Redeveloped Impervious Discharges to Cold or Warm Water Fishery? Modified CN for WQ (1.0") storm Note: Designers may use the Practice Drainage Area Runoff Calculator (second tab) for calculation of practice- specific runoff volumes for other treatment standards. Conveyance (4.3.5.2) Are inlets stabilized to ensure that non-erosive conditions exist for at least the 1-year, 24 hour storm? * Questions preceded by an asterix (*) may change based on previously entered values Have inlet pipes been set at the permanent pool or the base of the gravel bed? ↑Enter this value on the Standards Compliance Workbook Is outlet elevation designed such that a sub-surface water level is maintained in the gravel wetland? If the gravel wetland is designed with an organic soil layer at the surface, have vertical perforated riser pipes been provided to deliver stormwater stormwater from the surface down to the gravel bed? Have the outfalls and the conveyance to the discharge point been designed and protected to avoid erosion? Practice Type Yes No Yes No No No Yes Yes NoYes Cold Warm NoYes NoYes NoYes Shallow surface wetland Gravel wetland Page 1 of 4 15 Response Attachment location 16 ft3 1646 17 ft3 8232 18 ft3 9878 19* 20* 21 133.5%Yes 22 23 Response Attachment location 24 25 26 27 28 29 Does the planting plan specify that no woody vegetation >2 inches in diameter shall be planted or allowed to grow on the dam, within 15 feet of the dam or the toe of the embankment, or within 25 of a principal spillway outlet? What type of pretreatment is being used? Has an aquatic been been provided that extends at least 5 feet inward from the normal water edge and is no more than 18 inches deep? Has a setback been provided that extends 25 feet from the maximum design water surface elevation of the practice? Are all deep pool areas of ≥ 4 feet depth with side slopes steeper than 4:1 (H:V) surrounded by a safety bench with ≤6% slope extending 10 feet outward from the normal water edge to the toe of the side slope? Landscaping (4.3.6.5) Treatment (4.3.6.4) Has a minimum flow path at normal water level of 3:1 been provided? Attachment location: Indicate the specific location (i.e. appendix, page, plan sheet) where the requisite support documentation has been provided within the application. What is the volume stored in the forebay or other volumetric pre- treatment if used? (minimum 10% WQV) What is the volume stored in the permanent pool? What is the total WQV stored at the normal water level (pre- treatment + permanent pool)? Does the pre-treatment volume plus the permanent pool equal at least 50% of the WQV? Has a planting plan been prepared showing how aquatic and terrestrial areas will be stabilized, including plant species, plant locations, sources of plant material and any required soil amendments? Are any donor organic soils used in the practice obtained from a source other than natural wetlands? Is the remaining WQV provided for by extended detention over 24 hours? Swale Filter Strip Forebay (10% WQv) Deep Sump Catch Basins Proprietary NoYes NoYes NoYes Yes No NoYes NoYes NoYes NoYes NoYes NoYes Page 2 of 4 Practice Drainage Area Runoff Calculator Project Name: Discharge Point: Treatment Wetland # Precipitation Data NOAA Atlas 14 Storm WQ Storm 1 yr, 24 hr 10 yr, 24 hr 100 yr, 24 hr Precipitation (inches)1.00 1.90 3.25 4.85 Drainage Area Information Landuse A B C D Grass 0.000 0.000 0.000 0.000 0.000 Meadow 0.000 0.000 0.000 0.000 0.000 Woods 0.000 0.000 0.000 3.880 3.880 Pavement, roofs, and other impervious 0.000 0.000 0.000 0.000 0.000 Total 0.000 0.000 0.000 3.880 3.880 Landuse A B C D Grass 0.000 0.000 0.000 1.830 1.830 Meadow 0.000 0.000 0.000 0.000 0.000 Woods 0.000 0.000 0.000 0.000 0.000 Pavement, roofs, and other impervious 0.000 0.000 0.000 2.050 2.050 Total 0.000 0.000 0.000 3.880 3.880 TV of upstream practices:0.000 ac-ft TV credit of this practice:0.000 ac-ft Treatment Standard Required Treatment Volume Post Development Runoff Volume Pre- development Runoff Volume Post Composite CN (to practice) CNAdj (with TV practice credit) Pre Composite CN Channel Protection (Hydrologic Condition Method) 0.2349 0.3628 0.1279 92 92 77 Overbank Flood 0.3317 0.7351 0.4034 91 91 77 Extreme Flood 0.4017 1.2094 0.8077 90 90 77 Information for Calculating TC by the Watershed Lag Method 1 yr 10 yr 100 yr Time of Concentration, TC (min)Hydraulic Length, l (ft) Average Catchment Slope, Y (%) Hillside @ O'Brien Farm 8 6A Hydrologic Soil Group Total (acres) This tool may be used to calculate the required treatment volumes for the area draining to an individual practice where the practices drainage area is only a portion of of the area draining to a discharge point. Where the practice receives runoff from the entire area to a discharge point, this calculator will give the same information as the Standards Compliance Workbook. * Preciptation values shall be obtained from Pre Development Land Use (acres) Hydrologic Soil Group Total (acres) Post Development Land Use (acres) Pre Development 9.35%950.00 10.9 10.9 10.9 Post Development, upstream of practice 9.35%950.00 6.5 6.8 7.0 Post Development, with TV credit from practice 0.00%0.00 0.0 0.0 0.0 Version: 1/29/2018 Project Name:Hillside @ O'Brien Farm Phase2 Discharge Point: Treatment Wetland # Practice Drainage Area For Permit Coverage Not for Permit Coverage Total to Practice 1 Total Area (acres)5.310 0.000 5.310 2 2.340 0.000 2.340 3 0.000 0.000 WQV for credit WQV not for credit Total WQV 4 WQV to practice 0.1976 0.0000 0.1976 93 5 2 6 2 Response Attachment location 7 8 9 10 11* 12* 13* Response Attachment location 14 Forebay ↑Enter this value on the Standards Compliance Workbook Is outlet elevation designed such that a sub-surface water level is maintained in the gravel wetland? If the gravel wetland is designed with an organic soil layer at the surface, have vertical perforated riser pipes been provided to deliver stormwater stormwater from the surface down to the gravel bed? Have the outfalls and the conveyance to the discharge point been designed and protected to avoid erosion? Practice Type Discharges to Cold or Warm Water Fishery? Modified CN for WQ (1.0") storm Note: Designers may use the Practice Drainage Area Runoff Calculator (second tab) for calculation of practice- specific runoff volumes for other treatment standards. Conveyance (4.3.5.2) Are inlets stabilized to ensure that non-erosive conditions exist for at least the 1-year, 24 hour storm? * Questions preceded by an asterix (*) may change based on previously entered values Have inlet pipes been set at the permanent pool or the base of the gravel bed? New Impervious (acres) 8 6BTreatment Wetlands (4.3.5) Redeveloped Impervious Has a low for orifice been provided to meet the the WQV and CPV extended Has a liner designed in accordance with Section 4.3.5.2 been provided if the infiltration rate exceed 0.05 inches per hour and the wetland is located above Pre-Treatment (4.3.6.3) Has pretreatment been provided for non-rooftop runoff? Yes No Yes No No No Yes Yes NoYes Cold Warm NoYes NoYes NoYes Shallow surface wetland Gravel wetland Page 1 of 4 15 Response Attachment location 16 ft3 1646 17 ft3 8232 18 ft3 9878 19* 20* 21 114.7%Yes 22 23 Response Attachment location 24 25 26 27 28 29 Attachment location: Indicate the specific location (i.e. appendix, page, plan sheet) where the requisite support documentation has been provided within the application. What is the volume stored in the forebay or other volumetric pre- treatment if used? (minimum 10% WQV) What is the volume stored in the permanent pool? What is the total WQV stored at the normal water level (pre- treatment + permanent pool)? Does the pre-treatment volume plus the permanent pool equal at least 50% of the WQV? Has a planting plan been prepared showing how aquatic and terrestrial areas will be stabilized, including plant species, plant locations, sources of plant material and any required soil amendments? Are any donor organic soils used in the practice obtained from a source other than natural wetlands? Is the remaining WQV provided for by extended detention over 24 hours? Does the planting plan specify that no woody vegetation >2 inches in diameter shall be planted or allowed to grow on the dam, within 15 feet of the dam or the toe of the embankment, or within 25 of a principal spillway outlet? What type of pretreatment is being used? Has an aquatic been been provided that extends at least 5 feet inward from the normal water edge and is no more than 18 inches deep? Has a setback been provided that extends 25 feet from the maximum design water surface elevation of the practice? Are all deep pool areas of ≥ 4 feet depth with side slopes steeper than 4:1 (H:V) surrounded by a safety bench with ≤6% slope extending 10 feet outward from the normal water edge to the toe of the side slope? Landscaping (4.3.6.5) Treatment (4.3.6.4) Has a minimum flow path at normal water level of 3:1 been provided? Swale Filter Strip Forebay (10% WQv) Deep Sump Catch Basins Proprietary NoYes NoYes NoYes Yes No NoYes NoYes NoYes NoYes NoYes NoYes Page 2 of 4 Practice Drainage Area Runoff Calculator Project Name: Discharge Point: Treatment Wetland # Precipitation Data NOAA Atlas 14 Storm WQ Storm 1 yr, 24 hr 10 yr, 24 hr 100 yr, 24 hr Precipitation (inches)1.00 1.90 3.25 4.85 Drainage Area Information Landuse A B C D Grass 0.000 0.000 0.000 0.000 0.000 Meadow 0.000 0.000 0.000 0.000 0.000 Woods 0.000 0.000 0.000 5.310 5.310 Pavement, roofs, and other impervious 0.000 0.000 0.000 0.000 0.000 Total 0.000 0.000 0.000 5.310 5.310 Landuse A B C D Grass 0.000 0.000 0.000 2.970 2.970 Meadow 0.000 0.000 0.000 0.000 0.000 Woods 0.000 0.000 0.000 0.000 0.000 Pavement, roofs, and other impervious 0.000 0.000 0.000 2.340 2.340 Total 0.000 0.000 0.000 5.310 5.310 TV of upstream practices:0.000 ac-ft TV credit of this practice:0.000 ac-ft Treatment Standard Required Treatment Volume Post Development Runoff Volume Pre- development Runoff Volume Post Composite CN (to practice) CNAdj (with TV practice credit) Pre Composite CN Channel Protection (Hydrologic Condition Method) 0.2760 0.4511 0.1750 90 90 77 Overbank Flood 0.3928 0.9449 0.5521 89 89 77 Extreme Flood 0.4779 1.5833 1.1054 89 89 77 Information for Calculating TC by the Watershed Lag Method 1 yr 10 yr 100 yr Time of Concentration, TC (min)Hydraulic Length, l (ft) Average Catchment Slope, Y (%) Hillside @ O'Brien Farm 8 6B Hydrologic Soil Group Total (acres) This tool may be used to calculate the required treatment volumes for the area draining to an individual practice where the practices drainage area is only a portion of of the area draining to a discharge point. Where the practice receives runoff from the entire area to a discharge point, this calculator will give the same information as the Standards Compliance Workbook. * Preciptation values shall be obtained from Pre Development Land Use (acres) Hydrologic Soil Group Total (acres) Post Development Land Use (acres) Pre Development 9.35%1250.00 13.6 13.6 13.6 Post Development, upstream of practice 9.18%1250.00 8.7 9.1 9.3 Post Development, with TV credit from practice 9.35%0.00 0.0 0.0 0.0 Version: 1/29/2018 Project Name:Hillside @ O'Brien Farm Phase2 Discharge Point: Treatment Wetland # Practice Drainage Area For Permit Coverage Not for Permit Coverage Total to Practice 1 Total Area (acres)4.090 0.000 4.090 2 0.700 0.000 0.700 3 0.000 0.000 WQV for credit WQV not for credit Total WQV 4 WQV to practice 0.0695 0.0000 0.0695 86 5 2 6 2 Response Attachment location 7 8 9 10 11* 12* 13* Response Attachment location 14 Forebay New Impervious (acres) 9 7Treatment Wetlands (4.3.5) Has a low for orifice been provided to meet the the WQV and CPV extended Has a liner designed in accordance with Section 4.3.5.2 been provided if the infiltration rate exceed 0.05 inches per hour and the wetland is located above Redeveloped Impervious Pre-Treatment (4.3.6.3) Has pretreatment been provided for non-rooftop runoff? Practice Type Discharges to Cold or Warm Water Fishery? Modified CN for WQ (1.0") storm Note: Designers may use the Practice Drainage Area Runoff Calculator (second tab) for calculation of practice- specific runoff volumes for other treatment standards. Conveyance (4.3.5.2) Are inlets stabilized to ensure that non-erosive conditions exist for at least the 1-year, 24 hour storm? * Questions preceded by an asterix (*) may change based on previously entered values Have inlet pipes been set at the permanent pool or the base of the gravel bed? ↑Enter this value on the Standards Compliance Workbook Is outlet elevation designed such that a sub-surface water level is maintained in the gravel wetland? If the gravel wetland is designed with an organic soil layer at the surface, have vertical perforated riser pipes been provided to deliver stormwater stormwater from the surface down to the gravel bed? Have the outfalls and the conveyance to the discharge point been designed and protected to avoid erosion? Yes No Yes No No No Yes Yes NoYes Cold Warm NoYes NoYes NoYes Shallow surface wetland Gravel wetland Page 1 of 4 15 Response Attachment location 16 ft3 392 17 ft3 1958 18 ft3 2350 19* 20* 21 77.6%Yes 22 23 Response Attachment location 24 25 26 27 28 29 Does the planting plan specify that no woody vegetation >2 inches in diameter shall be planted or allowed to grow on the dam, within 15 feet of the dam or the toe of the embankment, or within 25 of a principal spillway outlet? What type of pretreatment is being used? Has an aquatic been been provided that extends at least 5 feet inward from the normal water edge and is no more than 18 inches deep? Has a setback been provided that extends 25 feet from the maximum design water surface elevation of the practice? Are all deep pool areas of ≥ 4 feet depth with side slopes steeper than 4:1 (H:V) surrounded by a safety bench with ≤6% slope extending 10 feet outward from the normal water edge to the toe of the side slope? Landscaping (4.3.6.5) Treatment (4.3.6.4) Has a minimum flow path at normal water level of 3:1 been provided? Attachment location: Indicate the specific location (i.e. appendix, page, plan sheet) where the requisite support documentation has been provided within the application. What is the volume stored in the forebay or other volumetric pre- treatment if used? (minimum 10% WQV) What is the volume stored in the permanent pool? What is the total WQV stored at the normal water level (pre- treatment + permanent pool)? Does the pre-treatment volume plus the permanent pool equal at least 50% of the WQV? Has a planting plan been prepared showing how aquatic and terrestrial areas will be stabilized, including plant species, plant locations, sources of plant material and any required soil amendments? Are any donor organic soils used in the practice obtained from a source other than natural wetlands? Is the remaining WQV provided for by extended detention over 24 hours? Swale Filter Strip Forebay (10% WQv) Deep Sump Catch Basins Proprietary NoYes NoYes NoYes Yes No NoYes NoYes NoYes NoYes NoYes NoYes Page 2 of 4 Practice Drainage Area Runoff Calculator Project Name: Discharge Point: Treatment Wetland # Precipitation Data NOAA Atlas 14 Storm WQ Storm 1 yr, 24 hr 10 yr, 24 hr 100 yr, 24 hr Precipitation (inches)1.00 1.90 3.25 4.85 Drainage Area Information Landuse A B C D Grass 0.000 0.000 0.000 0.000 0.000 Meadow 0.000 0.000 0.000 0.000 0.000 Woods 0.000 0.000 0.000 4.090 4.090 Pavement, roofs, and other impervious 0.000 0.000 0.000 0.000 0.000 Total 0.000 0.000 0.000 4.090 4.090 Landuse A B C D Grass 0.000 0.000 0.000 3.390 3.390 Meadow 0.000 0.000 0.000 0.000 0.000 Woods 0.000 0.000 0.000 0.000 0.000 Pavement, roofs, and other impervious 0.000 0.000 0.000 0.700 0.700 Total 0.000 0.000 0.000 4.090 4.090 TV of upstream practices:0.000 ac-ft TV credit of this practice:0.000 ac-ft Treatment Standard Required Treatment Volume Post Development Runoff Volume Pre- development Runoff Volume Post Composite CN (to practice) CNAdj (with TV practice credit) Pre Composite CN Channel Protection (Hydrologic Condition Method) 0.1049 0.2397 0.1348 85 85 77 Overbank Flood 0.1577 0.5829 0.4252 84 84 77 Extreme Flood 0.1981 1.0495 0.8514 83 83 77 Information for Calculating TC by the Watershed Lag Method 1 yr 10 yr 100 yr Time of Concentration, TC (min)Hydraulic Length, l (ft) Average Catchment Slope, Y (%) Hillside @ O'Brien Farm 9 7 Hydrologic Soil Group Total (acres) This tool may be used to calculate the required treatment volumes for the area draining to an individual practice where the practices drainage area is only a portion of of the area draining to a discharge point. Where the practice receives runoff from the entire area to a discharge point, this calculator will give the same information as the Standards Compliance Workbook. * Preciptation values shall be obtained from Pre Development Land Use (acres) Hydrologic Soil Group Total (acres) Post Development Land Use (acres) Pre Development 8.62%680.00 8.7 8.7 8.7 Post Development, upstream of practice 8.62%680.00 6.8 7.0 7.1 Post Development, with TV credit from practice 0.00%0.00 0.0 0.0 0.0 Version: 1/29/2018 Project Name:Hillside @ O'Brien Farm Phase2 Discharge Point: Treatment Wetland # Practice Drainage Area For Permit Coverage Not for Permit Coverage Total to Practice 1 Total Area (acres)12.700 0.000 12.700 2 1.000 0.000 1.000 3 0.000 0.000 WQV for credit WQV not for credit Total WQV 4 WQV to practice 0.1279 0.0000 0.1279 82 5 2 6 2 Response Attachment location 7 8 9 10 11* 12* 13* Response Attachment location 14 Forebay ↑Enter this value on the Standards Compliance Workbook Is outlet elevation designed such that a sub-surface water level is maintained in the gravel wetland? If the gravel wetland is designed with an organic soil layer at the surface, have vertical perforated riser pipes been provided to deliver stormwater stormwater from the surface down to the gravel bed? Have the outfalls and the conveyance to the discharge point been designed and protected to avoid erosion? Practice Type Discharges to Cold or Warm Water Fishery? Modified CN for WQ (1.0") storm Note: Designers may use the Practice Drainage Area Runoff Calculator (second tab) for calculation of practice- specific runoff volumes for other treatment standards. Conveyance (4.3.5.2) Are inlets stabilized to ensure that non-erosive conditions exist for at least the 1-year, 24 hour storm? * Questions preceded by an asterix (*) may change based on previously entered values Have inlet pipes been set at the permanent pool or the base of the gravel bed? New Impervious (acres) 6 10Treatment Wetlands (4.3.5) Redeveloped Impervious Has a low for orifice been provided to meet the the WQV and CPV extended Has a liner designed in accordance with Section 4.3.5.2 been provided if the infiltration rate exceed 0.05 inches per hour and the wetland is located above Pre-Treatment (4.3.6.3) Has pretreatment been provided for non-rooftop runoff? Yes No Yes No No No Yes Yes NoYes Cold Warm NoYes NoYes NoYes Shallow surface wetland Gravel wetland Page 1 of 4 15 Response Attachment location 16 ft3 81 17 ft3 401 18 ft3 482 19* 20* 21 8.7%No - revise design 22 23 Response Attachment location 24 25 26 27 28 29 Attachment location: Indicate the specific location (i.e. appendix, page, plan sheet) where the requisite support documentation has been provided within the application. What is the volume stored in the forebay or other volumetric pre- treatment if used? (minimum 10% WQV) What is the volume stored in the permanent pool? What is the total WQV stored at the normal water level (pre- treatment + permanent pool)? Does the pre-treatment volume plus the permanent pool equal at least 50% of the WQV? Has a planting plan been prepared showing how aquatic and terrestrial areas will be stabilized, including plant species, plant locations, sources of plant material and any required soil amendments? Are any donor organic soils used in the practice obtained from a source other than natural wetlands? Is the remaining WQV provided for by extended detention over 24 hours? Does the planting plan specify that no woody vegetation >2 inches in diameter shall be planted or allowed to grow on the dam, within 15 feet of the dam or the toe of the embankment, or within 25 of a principal spillway outlet? What type of pretreatment is being used? Has an aquatic been been provided that extends at least 5 feet inward from the normal water edge and is no more than 18 inches deep? Has a setback been provided that extends 25 feet from the maximum design water surface elevation of the practice? Are all deep pool areas of ≥ 4 feet depth with side slopes steeper than 4:1 (H:V) surrounded by a safety bench with ≤6% slope extending 10 feet outward from the normal water edge to the toe of the side slope? Landscaping (4.3.6.5) Treatment (4.3.6.4) Has a minimum flow path at normal water level of 3:1 been provided? Swale Filter Strip Forebay (10% WQv) Deep Sump Catch Basins Proprietary NoYes NoYes NoYes Yes No NoYes NoYes NoYes NoYes NoYes NoYes Page 2 of 4 Practice Drainage Area Runoff Calculator Project Name: Discharge Point: Treatment Wetland # Precipitation Data NOAA Atlas 14 Storm WQ Storm 1 yr, 24 hr 10 yr, 24 hr 100 yr, 24 hr Precipitation (inches)1.00 1.90 3.25 4.85 Drainage Area Information Landuse A B C D Grass 0.000 0.000 0.000 0.000 0.000 Meadow 0.000 0.000 0.000 0.000 0.000 Woods 0.000 0.000 0.000 12.700 12.700 Pavement, roofs, and other impervious 0.000 0.000 0.000 0.000 0.000 Total 0.000 0.000 0.000 12.700 12.700 Landuse A B C D Grass 0.000 0.000 0.000 11.700 11.700 Meadow 0.000 0.000 0.000 0.000 0.000 Woods 0.000 0.000 0.000 0.000 0.000 Pavement, roofs, and other impervious 0.000 0.000 0.000 1.000 1.000 Total 0.000 0.000 0.000 12.700 12.700 TV of upstream practices:0.000 ac-ft TV credit of this practice:0.000 ac-ft Treatment Standard Required Treatment Volume Post Development Runoff Volume Pre- development Runoff Volume Post Composite CN (to practice) CNAdj (with TV practice credit) Pre Composite CN Channel Protection (Hydrologic Condition Method) 0.2110 0.6296 0.4186 82 82 77 Overbank Flood 0.3355 1.6559 1.3204 82 82 77 Extreme Flood 0.4341 3.0778 2.6437 82 82 77 Information for Calculating TC by the Watershed Lag Method 1 yr 10 yr 100 yr Time of Concentration, TC (min)Hydraulic Length, l (ft) Average Catchment Slope, Y (%) Hillside @ O'Brien Farm 10 8 Hydrologic Soil Group Total (acres) This tool may be used to calculate the required treatment volumes for the area draining to an individual practice where the practices drainage area is only a portion of of the area draining to a discharge point. Where the practice receives runoff from the entire area to a discharge point, this calculator will give the same information as the Standards Compliance Workbook. * Preciptation values shall be obtained from Pre Development Land Use (acres) Hydrologic Soil Group Total (acres) Post Development Land Use (acres) Pre Development 5.20%960.00 14.8 14.8 14.8 Post Development, upstream of practice 5.20%960.00 12.5 12.7 12.8 Post Development, with TV credit from practice 0.00%0.00 0.0 0.0 0.0 Version: 4/28/2017 Project Name: Response Attachment location 1 Plan Sheet C-20.2 2 Plan Sheet C-20.2 Attachment Location Plan Sheet C-20.2 Plan Sheet C-20.2 Response Attachment location 5 Plan Sheet C-20.2 6 Plan Sheet C-20.2 7 Plan Sheet C-20.2 8 Plan Sheet C-20.2 9 NA Response Attachment location Option 1: Leave undisturbed native vegetation and soil, and protect from compaction during construction. Option 2: Amend existing site topsoil or subsoil in place. Option 3: Remove and stockpile existing topsoil during grading. Option 4: Import topsoil mix, or other materials for mixing, including compost, of sufficient organic content and depth. Is compost or other materials used to amend soils specified to have a C:N ratio below 25:1? Is it specified that compost shall meet the definition of "compost" or meet the contaminant standards in the Vermont Solid Waste Management Rules? If Exceptional Quality (EQ) biosolids are used as a soil amendment, do they comprise no more than 35% of the total volume of soil, and is it specifed that they be well mixed before or during application? Vegetation and Landscaping (3.3) Eastview Does the site layout retain the duff layer and native topsoil in an undisturbed state to the maximum extent practicable? Is the organic matter content of the topsoil layer specified to be at least 4%? 4 Feasibility (3.1) Have all areas that will not be disturbed and areas exempt from the Standard, including the reason for the exemtion, been identified on a plan sheet? Have all areas of disturbance within the site that are subject to the Post- Construction Soil Depth and Quality Standard been identified on a plan sheet? This includes all disturbed areas on slopes ≤ 33% which are not covered by an impervious surface, part of a structural stormwater treatment practice, or engineered as structural fill once development is complete. Which of the following methods are utilized to meet soil quality requirements for this site? Post-Construction Soil Depth and Quality Standard 3 Is the minimum topsoil depth specified as: 4 inches The depth of the 0 and A horizons on the NRCS Official Soil Series Description of the native mapped soils (provide documentation) Treatment (3.2) Yes No Yes No Yes No Yes No Yes No Yes No Yes No Page 1 of 2 10 Plan Sheet C-20.2 11 Plan Sheet C-20.2 12 Plan Sheet C-20.2 13 Plan Sheet C-20.2 14 Plan Sheet C-20.2 15 Plan Sheet C-20.2 Attachment location: Indicate the specific location (i.e. appendix, page, plan sheet) where the requisite support documentation has been provided within the application. Includes construction details and notes on the various methods the contractor may use to meet he Standard? Instructions to establish dense an vigorous vegeative cover over turf areas? Does the application include a site-specific plan for soil management that: Includes a statement that soil depth and quality shall be established towards the end of construction, and once established, be protected from compaction? Identifies all areas on the site subject to the standard? Includes instructions for contractor verification of the Standard, including a sampling scheme that includes nine 8-inch deep test holes per acre of area subject to the Standard? Instructions that test holes shall be excavated using only a shoven driven soley by the inspector's weight and shall be at least 50 feet apart from each other? Yes No Yes No Yes No Yes No Yes No Yes No Page 2 of 2 Version: 3/28/2018 Project Name: Discharge Point: Disconnection Area # Disconnected Area For Permit Coverage Not for Permit Coverage Total to Practice 1 Total Area (acres)3.830 0.000 3.830 2 0.307 0.000 0.307 WQV for credit WQV not for credit Total WQV 3 WQV to practice 0.0390 0.0000 0.0390 82 4 FALSE TRUE FALSE FALSE Response Attachment location 5 Sheets C-20 and D-7 6*Sheet D-7 7*Sheet D-7 8 Sheet D-7 9*Sheet D-7 10* 11 Sheet D-7 12 Sheets C-20 and D-7 13 NA 0 0 Response Attachment location 14 15 Eastview Simple Disconnection (4.2.2) 6 1 Conveyance (4.2.2.2) * Questions preceded by an asterix (*) may change based on previously entered values Feasibility (4.2.2.1) For areas conveyed by sheetflow, is the width of the disconnection area (perpendicular to the direction of flow) equal to or greater than the area being disconnected? For rooftop areas conveyed by downspouts, is the disconnection area at least 12 feet wide? For rooftop areas conveyed by downpouts, is the contributing area to any one discharge location no greater than 1,000 square feet? Do the underlying soils of the disconnection area meet the Post-Construction Soil Depth and Quality Standard? Is the maximum contributing impervious flow path length to any one discharge location no greater than 75 feet? Are disconnection areas configured such that there is no overlap between adjacent disconnection areas? Is the maximum slope of the disconnection area no steeper than 15%? For sites with septic systems, is the disconnection flow path cross-gradient or down-gradient of the leachfield? Is the runoff conveyed as sheet flow across the disconnection area for the applicable design storms and prevented from channelizing? Is the disconnection surface directed away from buildings so as to protect foundations and basements? Impervious (acres) Modified CN for WQ (1.0") storm Disconnected Area Type Yes No NoYes Yes No NoYes NoYes Yes No NoYes Yes No Yes No Yes No >10 ft, or conveyed by downspout Yes No 10 ft contributing length or less Page 1 of 3 16*Sheets C-20 and D-7 17*Sheets C-20 and D-7 18 Response Attachment location 19 Response Attachment location 20*acres 0.31 Sheets C-20 22*Sheets C-20 23*inches 0.00 24*ft 85.0 Sheets C-20 and D-7 25*ft 130.0 Sheets C-20 and D-7 3.00 2 Response Attachment location 26*acres 0 27*ft 0 28* 29* 30*inches 0.00 31*ft 0.0 32*ft 0.0 0 0 Disconnected Impervious Surface Required Disconnection Length for Contributing Areas >10 ft and Downspouts Required Disconnection for Contributing Areas ≤10 ft n/a, Disconnection area ≤10ft wide not selected in Question 4 What is the required length of the disconnention area for the rooftop runoff? What disconnection length is provided for the rooftop runoff? What is the slope of the disconnection area? 21*Soil HSG fc ≥1 in/hr for TV=HCV Are downspouts at least 10 feet from the nearest downgradient impervious surface to prevent reconnection? Has a stone diaphragm, level spreader, splash pad, or other acceptable flow spreading devide been specified for each downspout outlet? For runoff not conveyed by downspout, does the runoff drain either as sheet flow or drain to a subsurface drain field that is not directly connected to the drainage network? Pretreatment (4.2.2.3) Is runoff from qualifying surfaces prevented from co-mingling with other runoff, such that pre-treatment is not required? Treatment Volume Calculation fc ≥0.5 in/hr for TV=WQV fc <0.5 in/hr for TV=WQV A A/B <8% 8-15% C/D NoYes NoYes Yes No Yes No <8% 8-15% NoYes Page 2 of 3 33 TV (cu-ft)1114.41 34 TV (ac-ft)0.0256 Response Attachment location 35* Response Attachment location 36 Landscaping (4.3.2.5) Is a dense vegetative cover specified for the disconnection area on the plan sheet/detail sheet? Attachment location: Indicate the specific location (i.e. appendix, page, plan sheet) where the requisite support documentation has been provided within the application. What is the treatment volume provided by the STP? What is the treatment volume provided by the STP? ↑ Enter this value on the Standards Compliance Worksheet Treatment (4.2.2.4) NoYes NoYes Page 3 of 3 WQv 229S GW3 230S GW4 231S GW5 232S GW6A 233S GW7 234S GW8 254S GW6B 222P GravelWet3 224P GravelWet4 226P GravelWet6A 227P GravelWet7 254P GravelWet5 257P GravelWet6B 268P GravelWet8 Routing Diagram for Eastview2022-postPrepared by Krebs & Lansing Consulting Engineers, Inc., Printed 4/7/2022 HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Subcat Reach Pond Link Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 2HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Project Notes EASTVIEW Old Farm Road & Kimball Avenue South Burlington, Vermont Post Development Stormwater Model Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 3HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Area Listing (selected nodes) Area (acres) CN Description (subcatchment-numbers) 6.550 95 Workbook (229S) 12.400 93 Workbook (230S, 254S) 15.520 89 Workbook (231S) 3.880 94 Workbook (232S) 4.090 86 Workbook (233S) 12.700 82 Workbook (234S) 55.140 89 TOTAL AREA Type II 24-hr WQv-1inch Rainfall=1.00"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 4HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Time span=0.00-128.00 hrs, dt=0.01 hrs, 12801 points Runoff by SCS TR-20 method, UH=SCS, Weighted-Q Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=6.550 ac Runoff Depth=0.56"Subcatchment 229S: GW3 Tc=11.3 min CN=95 Runoff=5.41 cfs 0.307 af Runoff Area=7.080 ac Runoff Depth=0.45"Subcatchment 230S: GW4 Tc=7.9 min CN=93 Runoff=5.32 cfs 0.266 af Runoff Area=15.520 ac Runoff Depth=0.28"Subcatchment 231S: GW5 Tc=13.0 min CN=89 Runoff=5.81 cfs 0.369 af Runoff Area=3.880 ac Runoff Depth=0.50"Subcatchment 232S: GW6A Tc=6.5 min CN=94 Runoff=3.43 cfs 0.163 af Runoff Area=4.090 ac Runoff Depth=0.20"Subcatchment 233S: GW7 Tc=6.8 min CN=86 Runoff=1.27 cfs 0.067 af Runoff Area=12.700 ac Runoff Depth=0.11"Subcatchment 234S: GW8 Tc=12.5 min CN=82 Runoff=1.25 cfs 0.121 af Runoff Area=5.320 ac Runoff Depth=0.45"Subcatchment 254S: GW6B Tc=8.7 min CN=93 Runoff=3.88 cfs 0.200 af Peak Elev=373.89' Storage=14,659 cf Inflow=5.41 cfs 0.307 afPond 222P: GravelWet3 Outflow=0.22 cfs 0.307 af Peak Elev=380.94' Storage=11,685 cf Inflow=5.32 cfs 0.266 afPond 224P: GravelWet4 Outflow=0.18 cfs 0.266 af Peak Elev=376.85' Storage=7,473 cf Inflow=3.43 cfs 0.163 afPond 226P: GravelWet6A Outflow=0.11 cfs 0.163 af Peak Elev=328.07' Storage=11,161 cf Inflow=1.27 cfs 0.067 afPond 227P: GravelWet7 Outflow=0.09 cfs 0.067 af Peak Elev=365.82' Storage=17,070 cf Inflow=5.81 cfs 0.369 afPond 254P: GravelWet5 Outflow=0.22 cfs 0.369 af Peak Elev=333.25' Storage=9,860 cf Inflow=3.88 cfs 0.200 afPond 257P: GravelWet6B Outflow=0.13 cfs 0.200 af Peak Elev=331.15' Storage=10,439 cf Inflow=1.25 cfs 0.121 afPond 268P: GravelWet8 Outflow=0.12 cfs 0.121 af Total Runoff Area = 55.140 ac Runoff Volume = 1.492 af Average Runoff Depth = 0.32" Type II 24-hr WQv-1inch Rainfall=1.00"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 5HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 229S: GW3 Runoff = 5.41 cfs @ 12.03 hrs, Volume= 0.307 af, Depth= 0.56" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Type II 24-hr WQv-1inch Rainfall=1.00" Area (ac) CN Description * 6.550 95 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 11.3 Direct Entry, Workbook- Lag Subcatchment 229S: GW3 Runoff Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)6 5 4 3 2 1 0 Type II 24-hr WQv-1inch Rainfall=1.00" Runoff Area=6.550 ac Runoff Volume=0.307 af Runoff Depth=0.56" Tc=11.3 min CN=95 5.41 cfs Type II 24-hr WQv-1inch Rainfall=1.00"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 6HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 230S: GW4 Runoff = 5.32 cfs @ 12.00 hrs, Volume= 0.266 af, Depth= 0.45" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Type II 24-hr WQv-1inch Rainfall=1.00" Area (ac) CN Description * 7.080 93 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 7.9 Direct Entry, Workbook- Lag Subcatchment 230S: GW4 Runoff Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)5 4 3 2 1 0 Type II 24-hr WQv-1inch Rainfall=1.00" Runoff Area=7.080 ac Runoff Volume=0.266 af Runoff Depth=0.45" Tc=7.9 min CN=93 5.32 cfs Type II 24-hr WQv-1inch Rainfall=1.00"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 7HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 231S: GW5 Runoff = 5.81 cfs @ 12.06 hrs, Volume= 0.369 af, Depth= 0.28" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Type II 24-hr WQv-1inch Rainfall=1.00" Area (ac) CN Description * 15.520 89 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 13.0 Direct Entry, Workbook- Lag Subcatchment 231S: GW5 Runoff Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)6 5 4 3 2 1 0 Type II 24-hr WQv-1inch Rainfall=1.00" Runoff Area=15.520 ac Runoff Volume=0.369 af Runoff Depth=0.28" Tc=13.0 min CN=89 5.81 cfs Type II 24-hr WQv-1inch Rainfall=1.00"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 8HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 232S: GW6A Runoff = 3.43 cfs @ 11.98 hrs, Volume= 0.163 af, Depth= 0.50" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Type II 24-hr WQv-1inch Rainfall=1.00" Area (ac) CN Description * 3.880 94 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.5 Direct Entry, Workbook- Lag Subcatchment 232S: GW6A Runoff Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)3 2 1 0 Type II 24-hr WQv-1inch Rainfall=1.00" Runoff Area=3.880 ac Runoff Volume=0.163 af Runoff Depth=0.50" Tc=6.5 min CN=94 3.43 cfs Type II 24-hr WQv-1inch Rainfall=1.00"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 9HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 233S: GW7 Runoff = 1.27 cfs @ 12.00 hrs, Volume= 0.067 af, Depth= 0.20" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Type II 24-hr WQv-1inch Rainfall=1.00" Area (ac) CN Description * 4.090 86 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.8 Direct Entry, Workbook- Lag Subcatchment 233S: GW7 Runoff Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)1 0 Type II 24-hr WQv-1inch Rainfall=1.00" Runoff Area=4.090 ac Runoff Volume=0.067 af Runoff Depth=0.20" Tc=6.8 min CN=86 1.27 cfs Type II 24-hr WQv-1inch Rainfall=1.00"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 10HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 234S: GW8 Runoff = 1.25 cfs @ 12.09 hrs, Volume= 0.121 af, Depth= 0.11" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Type II 24-hr WQv-1inch Rainfall=1.00" Area (ac) CN Description * 12.700 82 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 12.5 Direct Entry, Workbook- Lag Subcatchment 234S: GW8 Runoff Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)1 0 Type II 24-hr WQv-1inch Rainfall=1.00" Runoff Area=12.700 ac Runoff Volume=0.121 af Runoff Depth=0.11" Tc=12.5 min CN=82 1.25 cfs Type II 24-hr WQv-1inch Rainfall=1.00"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 11HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 254S: GW6B Runoff = 3.88 cfs @ 12.01 hrs, Volume= 0.200 af, Depth= 0.45" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Type II 24-hr WQv-1inch Rainfall=1.00" Area (ac) CN Description * 5.320 93 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 8.7 Direct Entry, Workbook- Lag Subcatchment 254S: GW6B Runoff Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)4 3 2 1 0 Type II 24-hr WQv-1inch Rainfall=1.00" Runoff Area=5.320 ac Runoff Volume=0.200 af Runoff Depth=0.45" Tc=8.7 min CN=93 3.88 cfs Type II 24-hr WQv-1inch Rainfall=1.00"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 12HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 222P: GravelWet3 Inflow Area = 6.550 ac, Inflow Depth = 0.56" for WQv-1inch event Inflow = 5.41 cfs @ 12.03 hrs, Volume= 0.307 af Outflow = 0.22 cfs @ 14.02 hrs, Volume= 0.307 af, Atten= 96%, Lag= 119.6 min Primary = 0.22 cfs @ 14.02 hrs, Volume= 0.307 af Routing by Stor-Ind method, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Starting Elev= 372.67' Surf.Area= 14,880 sf Storage= 7,187 cf Peak Elev= 373.89' @ 14.02 hrs Surf.Area= 23,680 sf Storage= 14,659 cf (7,472 cf above start) Plug-Flow detention time= 853.4 min calculated for 0.143 af (46% of inflow) Center-of-Mass det. time= 405.7 min ( 1,231.5 - 825.8 ) Volume Invert Avail.Storage Storage Description #1 370.00' 6,934 cf Custom Stage Data (Prismatic) Listed below (Recalc) 17,335 cf Overall x 40.0% Voids #2 372.33' 498 cf Custom Stage Data (Prismatic) Listed below (Recalc) 4,985 cf Overall x 10.0% Voids #3 373.00' 34,521 cf Custom Stage Data (Prismatic) Listed below (Recalc) 41,953 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 370.00 7,440 0 0 372.33 7,440 17,335 17,335 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 372.33 7,440 0 0 373.00 7,440 4,985 4,985 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 373.00 7,440 0 0 374.00 8,968 8,204 8,204 375.00 10,193 9,581 17,785 376.00 11,474 10,834 28,618 376.50 12,136 5,903 34,521 Device Routing Invert Outlet Devices #1 Primary 372.67'24.0" Round Culvert L= 15.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 372.67' / 371.00' S= 0.1113 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 3.14 sf #2 Device 1 372.67'2.8" Vert. Orifice/Grate C= 0.600 #3 Device 1 373.90'1.0" Vert. Orifice/Grate C= 0.600 #4 Device 1 375.00'48.0" W x 12.0" H Vert. Orifice/Grate C= 0.600 Type II 24-hr WQv-1inch Rainfall=1.00"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 13HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Primary OutFlow Max=0.22 cfs @ 14.02 hrs HW=373.89' (Free Discharge) 1=Culvert (Passes 0.22 cfs of 5.96 cfs potential flow) 2=Orifice/Grate (Orifice Controls 0.22 cfs @ 5.06 fps) 3=Orifice/Grate ( Controls 0.00 cfs) 4=Orifice/Grate ( Controls 0.00 cfs) Pond 222P: GravelWet3 Inflow Primary Hydrograph Time (hours)12512011511010510095908580757065605550454035302520151050Flow (cfs)6 5 4 3 2 1 0 Inflow Area=6.550 ac Peak Elev=373.89' Storage=14,659 cf 5.41 cfs 0.22 cfs Type II 24-hr WQv-1inch Rainfall=1.00"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 14HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 224P: GravelWet4 Inflow Area = 7.080 ac, Inflow Depth = 0.45" for WQv-1inch event Inflow = 5.32 cfs @ 12.00 hrs, Volume= 0.266 af Outflow = 0.18 cfs @ 14.52 hrs, Volume= 0.266 af, Atten= 97%, Lag= 151.4 min Primary = 0.18 cfs @ 14.52 hrs, Volume= 0.266 af Routing by Stor-Ind method, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Starting Elev= 379.67' Surf.Area= 10,880 sf Storage= 5,255 cf Peak Elev= 380.94' @ 14.52 hrs Surf.Area= 18,748 sf Storage= 11,685 cf (6,430 cf above start) Plug-Flow detention time= 841.2 min calculated for 0.145 af (55% of inflow) Center-of-Mass det. time= 435.9 min ( 1,275.3 - 839.4 ) Volume Invert Avail.Storage Storage Description #1 377.00' 5,070 cf Custom Stage Data (Prismatic) Listed below (Recalc) 12,675 cf Overall x 40.0% Voids #2 379.33' 364 cf Custom Stage Data (Prismatic) Listed below (Recalc) 3,645 cf Overall x 10.0% Voids #3 380.00' 34,618 cf Custom Stage Data (Prismatic) Listed below (Recalc) 40,053 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 377.00 5,440 0 0 379.33 5,440 12,675 12,675 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 379.33 5,440 0 0 380.00 5,440 3,645 3,645 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 380.00 5,440 0 0 381.00 8,025 6,733 6,733 382.00 9,537 8,781 15,514 383.00 11,105 10,321 25,835 383.75 12,318 8,784 34,618 Device Routing Invert Outlet Devices #1 Primary 379.67'18.0" Round Culvert L= 15.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 379.67' / 378.00' S= 0.1113 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf #2 Device 1 379.67'2.5" Vert. Orifice/Grate C= 0.600 #3 Device 1 380.95'1.0" Vert. Orifice/Grate C= 0.600 #4 Device 1 382.50'48.0" W x 6.0" H Vert. Orifice/Grate C= 0.600 #5 Primary 383.00'8.0' long x 4.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Type II 24-hr WQv-1inch Rainfall=1.00"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 15HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Coef. (English) 2.38 2.54 2.69 2.68 2.67 2.67 2.65 2.66 2.66 2.68 2.72 2.73 2.76 2.79 2.88 3.07 3.32 Primary OutFlow Max=0.18 cfs @ 14.52 hrs HW=380.94' (Free Discharge) 1=Culvert (Passes 0.18 cfs of 4.83 cfs potential flow) 2=Orifice/Grate (Orifice Controls 0.18 cfs @ 5.20 fps) 3=Orifice/Grate ( Controls 0.00 cfs) 4=Orifice/Grate ( Controls 0.00 cfs) 5=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Pond 224P: GravelWet4 InflowPrimary Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)5 4 3 2 1 0 Inflow Area=7.080 ac Peak Elev=380.94' Storage=11,685 cf 5.32 cfs 0.18 cfs Type II 24-hr WQv-1inch Rainfall=1.00"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 16HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 226P: GravelWet6A Inflow Area = 3.880 ac, Inflow Depth = 0.50" for WQv-1inch event Inflow = 3.43 cfs @ 11.98 hrs, Volume= 0.163 af Outflow = 0.11 cfs @ 14.18 hrs, Volume= 0.163 af, Atten= 97%, Lag= 131.8 min Primary = 0.11 cfs @ 14.18 hrs, Volume= 0.163 af Routing by Stor-Ind method, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Starting Elev= 375.67' Surf.Area= 7,300 sf Storage= 3,526 cf Peak Elev= 376.85' @ 14.18 hrs Surf.Area= 12,631 sf Storage= 7,473 cf (3,948 cf above start) Plug-Flow detention time= 847.9 min calculated for 0.082 af (50% of inflow) Center-of-Mass det. time= 421.0 min ( 1,251.1 - 830.1 ) Volume Invert Avail.Storage Storage Description #1 373.00' 3,402 cf Custom Stage Data (Prismatic) Listed below (Recalc) 8,504 cf Overall x 40.0% Voids #2 375.33' 245 cf Custom Stage Data (Prismatic) Listed below (Recalc) 2,446 cf Overall x 10.0% Voids #3 376.00' 21,800 cf Custom Stage Data (Prismatic) Listed below (Recalc) 25,446 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 373.00 3,650 0 0 375.33 3,650 8,504 8,504 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 375.33 3,650 0 0 376.00 3,650 2,446 2,446 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 376.00 3,650 0 0 377.00 5,622 4,636 4,636 378.00 6,595 6,109 10,745 379.00 7,624 7,110 17,854 379.50 8,160 3,946 21,800 Device Routing Invert Outlet Devices #1 Primary 375.67'18.0" Round Culvert L= 90.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 375.67' / 370.00' S= 0.0630 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf #2 Device 1 375.67'2.0" Vert. Orifice/Grate C= 0.600 #3 Device 1 376.90'1.0" Vert. Orifice/Grate C= 0.600 #4 Device 1 377.90'48.0" W x 6.0" H Vert. Orifice/Grate C= 0.600 Type II 24-hr WQv-1inch Rainfall=1.00"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 17HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Primary OutFlow Max=0.11 cfs @ 14.18 hrs HW=376.85' (Free Discharge) 1=Culvert (Passes 0.11 cfs of 4.37 cfs potential flow) 2=Orifice/Grate (Orifice Controls 0.11 cfs @ 5.05 fps) 3=Orifice/Grate ( Controls 0.00 cfs) 4=Orifice/Grate ( Controls 0.00 cfs) Pond 226P: GravelWet6A Inflow Primary Hydrograph Time (hours)12512011511010510095908580757065605550454035302520151050Flow (cfs)3 2 1 0 Inflow Area=3.880 ac Peak Elev=376.85' Storage=7,473 cf 3.43 cfs 0.11 cfs Type II 24-hr WQv-1inch Rainfall=1.00"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 18HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 227P: GravelWet7 Inflow Area = 4.090 ac, Inflow Depth = 0.20" for WQv-1inch event Inflow = 1.27 cfs @ 12.00 hrs, Volume= 0.067 af Outflow = 0.09 cfs @ 13.32 hrs, Volume= 0.067 af, Atten= 93%, Lag= 79.4 min Primary = 0.09 cfs @ 13.32 hrs, Volume= 0.067 af Routing by Stor-Ind method, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Starting Elev= 327.67' Surf.Area= 20,916 sf Storage= 10,102 cf Peak Elev= 328.07' @ 13.32 hrs Surf.Area= 31,720 sf Storage= 11,161 cf (1,058 cf above start) Plug-Flow detention time= (not calculated: initial storage exceeds outflow) Center-of-Mass det. time= 136.1 min ( 1,026.4 - 890.4 ) Volume Invert Avail.Storage Storage Description #1 325.00' 9,747 cf Custom Stage Data (Prismatic) Listed below (Recalc) 24,367 cf Overall x 40.0% Voids #2 327.33' 701 cf Custom Stage Data (Prismatic) Listed below (Recalc) 7,007 cf Overall x 10.0% Voids #3 328.00' 68,080 cf Custom Stage Data (Prismatic) Listed below (Recalc) 78,528 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 325.00 10,458 0 0 327.33 10,458 24,367 24,367 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 327.33 10,458 0 0 328.00 10,458 7,007 7,007 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 328.00 10,458 0 0 329.00 15,610 13,034 13,034 330.00 17,405 16,508 29,542 331.00 19,255 18,330 47,872 332.00 21,162 20,209 68,080 Device Routing Invert Outlet Devices #1 Primary 327.67'18.0" Round Culvert L= 57.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 327.67' / 327.10' S= 0.0100 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf #2 Device 1 327.67'2.5" Vert. Orifice/Grate C= 0.600 #3 Device 1 328.10'1.0" Vert. Orifice/Grate C= 0.600 #4 Device 1 328.50'6.0" Vert. Orifice/Grate C= 0.600 #5 Device 1 330.50'48.0" W x 6.0" H Vert. Orifice/Grate C= 0.600 #6 Primary 331.00'8.0' long x 4.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 Type II 24-hr WQv-1inch Rainfall=1.00"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 19HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef. (English) 2.38 2.54 2.69 2.68 2.67 2.67 2.65 2.66 2.66 2.68 2.72 2.73 2.76 2.79 2.88 3.07 3.32 Primary OutFlow Max=0.09 cfs @ 13.32 hrs HW=328.07' (Free Discharge) 1=Culvert (Passes 0.09 cfs of 0.63 cfs potential flow) 2=Orifice/Grate (Orifice Controls 0.09 cfs @ 2.61 fps) 3=Orifice/Grate ( Controls 0.00 cfs) 4=Orifice/Grate ( Controls 0.00 cfs) 5=Orifice/Grate ( Controls 0.00 cfs) 6=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Pond 227P: GravelWet7 InflowPrimary Hydrograph Time (hours)12512011511010510095908580757065605550454035302520151050Flow (cfs)1 0 Inflow Area=4.090 ac Peak Elev=328.07' Storage=11,161 cf 1.27 cfs 0.09 cfs Type II 24-hr WQv-1inch Rainfall=1.00"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 20HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 254P: GravelWet5 Inflow Area = 15.520 ac, Inflow Depth = 0.28" for WQv-1inch event Inflow = 5.81 cfs @ 12.06 hrs, Volume= 0.369 af Outflow = 0.22 cfs @ 15.82 hrs, Volume= 0.369 af, Atten= 96%, Lag= 225.6 min Primary = 0.22 cfs @ 15.82 hrs, Volume= 0.369 af Routing by Stor-Ind method, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Starting Elev= 364.67' Surf.Area= 17,280 sf Storage= 8,346 cf Peak Elev= 365.82' @ 15.82 hrs Surf.Area= 29,209 sf Storage= 17,070 cf (8,724 cf above start) Plug-Flow detention time= 986.1 min calculated for 0.177 af (48% of inflow) Center-of-Mass det. time= 487.2 min ( 1,360.3 - 873.2 ) Volume Invert Avail.Storage Storage Description #1 362.00' 8,052 cf Custom Stage Data (Prismatic) Listed below (Recalc) 20,131 cf Overall x 40.0% Voids #2 364.33' 579 cf Custom Stage Data (Prismatic) Listed below (Recalc) 5,789 cf Overall x 10.0% Voids #3 365.00' 64,384 cf Custom Stage Data (Prismatic) Listed below (Recalc) 73,015 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 362.00 8,640 0 0 364.33 8,640 20,131 20,131 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 364.33 8,640 0 0 365.00 8,640 5,789 5,789 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 365.00 8,640 0 0 366.00 12,649 10,645 10,645 367.00 14,154 13,402 24,046 368.00 15,717 14,936 38,982 369.00 17,336 16,527 55,508 369.50 18,166 8,876 64,384 Device Routing Invert Outlet Devices #1 Primary 364.67'18.0" Round Culvert L= 37.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 364.67' / 358.00' S= 0.1803 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf #2 Device 1 364.67'2.9" Vert. Orifice/Grate C= 0.600 #3 Device 1 365.83'1.0" Vert. Orifice/Grate C= 0.600 #4 Device 1 367.50'48.0" W x 6.0" H Vert. Orifice/Grate C= 0.600 #5 Primary 368.00'8.0' long x 4.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 Type II 24-hr WQv-1inch Rainfall=1.00"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 21HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef. (English) 2.38 2.54 2.69 2.68 2.67 2.67 2.65 2.66 2.66 2.68 2.72 2.73 2.76 2.79 2.88 3.07 3.32 Primary OutFlow Max=0.22 cfs @ 15.82 hrs HW=365.82' (Free Discharge) 1=Culvert (Passes 0.22 cfs of 4.19 cfs potential flow) 2=Orifice/Grate (Orifice Controls 0.22 cfs @ 4.89 fps) 3=Orifice/Grate ( Controls 0.00 cfs) 4=Orifice/Grate ( Controls 0.00 cfs) 5=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Pond 254P: GravelWet5 InflowPrimary Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)6 5 4 3 2 1 0 Inflow Area=15.520 ac Peak Elev=365.82' Storage=17,070 cf 5.81 cfs 0.22 cfs Type II 24-hr WQv-1inch Rainfall=1.00"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 22HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 257P: GravelWet6B Inflow Area = 5.320 ac, Inflow Depth = 0.45" for WQv-1inch event Inflow = 3.88 cfs @ 12.01 hrs, Volume= 0.200 af Outflow = 0.13 cfs @ 14.80 hrs, Volume= 0.200 af, Atten= 97%, Lag= 167.9 min Primary = 0.13 cfs @ 14.80 hrs, Volume= 0.200 af Routing by Stor-Ind method, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Starting Elev= 332.17' Surf.Area= 10,260 sf Storage= 4,956 cf Peak Elev= 333.25' @ 14.80 hrs Surf.Area= 17,461 sf Storage= 9,860 cf (4,905 cf above start) Plug-Flow detention time= 969.1 min calculated for 0.086 af (43% of inflow) Center-of-Mass det. time= 463.6 min ( 1,303.7 - 840.1 ) Volume Invert Avail.Storage Storage Description #1 329.50' 4,781 cf Custom Stage Data (Prismatic) Listed below (Recalc) 11,953 cf Overall x 40.0% Voids #2 331.83' 344 cf Custom Stage Data (Prismatic) Listed below (Recalc) 3,437 cf Overall x 10.0% Voids #3 332.50' 30,552 cf Custom Stage Data (Prismatic) Listed below (Recalc) 35,677 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 329.50 5,130 0 0 331.83 5,130 11,953 11,953 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 331.83 5,130 0 0 332.50 5,130 3,437 3,437 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 332.50 5,130 0 0 333.00 6,813 2,986 2,986 334.00 8,365 7,589 10,575 335.00 9,975 9,170 19,745 336.00 11,640 10,808 30,552 Device Routing Invert Outlet Devices #1 Primary 332.17'24.0" Round Culvert L= 284.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 332.17' / 330.75' S= 0.0050 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 3.14 sf #2 Device 1 332.17'2.2" Vert. Orifice/Grate C= 0.600 #3 Device 1 333.25'1.0" Vert. Orifice/Grate C= 0.600 #4 Device 1 334.20'24.0" x 24.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Type II 24-hr WQv-1inch Rainfall=1.00"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 23HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Primary OutFlow Max=0.13 cfs @ 14.80 hrs HW=333.25' (Free Discharge) 1=Culvert (Passes 0.13 cfs of 4.83 cfs potential flow) 2=Orifice/Grate (Orifice Controls 0.13 cfs @ 4.79 fps) 3=Orifice/Grate ( Controls 0.00 cfs) 4=Orifice/Grate ( Controls 0.00 cfs) Pond 257P: GravelWet6B Inflow Primary Hydrograph Time (hours)12512011511010510095908580757065605550454035302520151050Flow (cfs)4 3 2 1 0 Inflow Area=5.320 ac Peak Elev=333.25' Storage=9,860 cf 3.88 cfs 0.13 cfs Type II 24-hr WQv-1inch Rainfall=1.00"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 24HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 268P: GravelWet8 Inflow Area = 12.700 ac, Inflow Depth = 0.11" for WQv-1inch event Inflow = 1.25 cfs @ 12.09 hrs, Volume= 0.121 af Outflow = 0.12 cfs @ 14.97 hrs, Volume= 0.121 af, Atten= 91%, Lag= 173.0 min Primary = 0.12 cfs @ 14.97 hrs, Volume= 0.121 af Routing by Stor-Ind method, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Starting Elev= 330.67' Surf.Area= 18,000 sf Storage= 8,694 cf Peak Elev= 331.15' @ 14.97 hrs Surf.Area= 27,723 sf Storage= 10,439 cf (1,745 cf above start) Plug-Flow detention time= (not calculated: initial storage exceeds outflow) Center-of-Mass det. time= 185.4 min ( 1,118.8 - 933.4 ) Volume Invert Avail.Storage Storage Description #1 328.00' 8,388 cf Custom Stage Data (Prismatic) Listed below (Recalc) 20,970 cf Overall x 40.0% Voids #2 330.33' 603 cf Custom Stage Data (Prismatic) Listed below (Recalc) 6,030 cf Overall x 10.0% Voids #3 331.00' 51,235 cf Custom Stage Data (Prismatic) Listed below (Recalc) 60,226 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 328.00 9,000 0 0 330.33 9,000 20,970 20,970 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 330.33 9,000 0 0 331.00 9,000 6,030 6,030 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 331.00 9,000 0 0 332.00 13,677 11,339 11,339 333.00 15,480 14,579 25,917 334.00 17,340 16,410 42,327 334.50 18,291 8,908 51,235 Device Routing Invert Outlet Devices #1 Primary 330.67'18.0" Round Culvert L= 40.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 330.67' / 330.35' S= 0.0080 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf #2 Device 1 330.67'2.7" Vert. Orifice/Grate C= 0.600 #3 Device 1 331.20'1.0" Vert. Orifice/Grate C= 0.600 #4 Device 1 332.40'6.0" Vert. Orifice/Grate C= 0.600 #5 Device 1 333.00'48.0" W x 6.0" H Vert. Orifice/Grate C= 0.600 #6 Primary 333.50'8.0' long x 4.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 Type II 24-hr WQv-1inch Rainfall=1.00"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 25HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef. (English) 2.38 2.54 2.69 2.68 2.67 2.67 2.65 2.66 2.66 2.68 2.72 2.73 2.76 2.79 2.88 3.07 3.32 Primary OutFlow Max=0.12 cfs @ 14.97 hrs HW=331.15' (Free Discharge) 1=Culvert (Passes 0.12 cfs of 0.92 cfs potential flow) 2=Orifice/Grate (Orifice Controls 0.12 cfs @ 2.94 fps) 3=Orifice/Grate ( Controls 0.00 cfs) 4=Orifice/Grate ( Controls 0.00 cfs) 5=Orifice/Grate ( Controls 0.00 cfs) 6=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Pond 268P: GravelWet8 InflowPrimary Hydrograph Time (hours)12512011511010510095908580757065605550454035302520151050Flow (cfs)1 0 Inflow Area=12.700 ac Peak Elev=331.15' Storage=10,439 cf 1.25 cfs 0.12 cfs 216P GW3-Forebay 217P GW4-Forebay 218P GW5-Forebay 219P GW6A-Forebay 220P GW7-Forebay 221P GW8-Forebay 245P GW6B-Forebay Routing Diagram for Eastview2022-postPrepared by Krebs & Lansing Consulting Engineers, Inc., Printed 4/6/2022 HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Subcat Reach Pond Link Type II 24-hr 1 Year Rainfall=1.90"Eastview2022-post Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 5HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 216P: GW3-Forebay Volume Invert Avail.Storage Storage Description #1 374.00' 1,889 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 374.00 200 0 0 375.00 399 300 300 376.00 655 527 827 377.00 967 811 1,638 377.25 1,045 252 1,889 Type II 24-hr 1 Year Rainfall=1.90"Eastview2022-post Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 6HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 217P: GW4-Forebay Volume Invert Avail.Storage Storage Description #1 378.00' 1,319 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 378.00 169 0 0 379.00 361 265 265 380.00 625 493 758 380.75 870 561 1,319 Type II 24-hr 1 Year Rainfall=1.90"Eastview2022-post Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 7HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 218P: GW5-Forebay Volume Invert Avail.Storage Storage Description #1 362.50' 2,601 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 362.50 280 0 0 363.00 408 172 172 364.00 724 566 738 365.00 1,120 922 1,660 365.75 1,388 941 2,601 Type II 24-hr 1 Year Rainfall=1.90"Eastview2022-post Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 8HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 219P: GW6A-Forebay Volume Invert Avail.Storage Storage Description #1 373.00' 1,132 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 373.00 74 0 0 374.00 175 125 125 375.00 408 292 416 376.00 477 443 859 376.50 615 273 1,132 Type II 24-hr 1 Year Rainfall=1.90"Eastview2022-post Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 9HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 220P: GW7-Forebay Volume Invert Avail.Storage Storage Description #1 325.75' 6,208 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 325.75 1,187 0 0 326.00 1,393 323 323 327.00 1,911 1,652 1,975 328.00 2,496 2,204 4,178 328.75 2,918 2,030 6,208 Type II 24-hr 1 Year Rainfall=1.90"Eastview2022-post Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 10HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 221P: GW8-Forebay Volume Invert Avail.Storage Storage Description #1 329.00' 4,358 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 329.00 988 0 0 330.00 1,400 1,194 1,194 331.00 1,868 1,634 2,828 331.75 2,212 1,530 4,358 Type II 24-hr 1 Year Rainfall=1.90"Eastview2022-post Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 11HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 245P: GW6B-Forebay Volume Invert Avail.Storage Storage Description #1 329.50' 1,240 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 329.50 112 0 0 330.00 186 75 75 331.00 307 247 321 332.00 453 380 701 333.00 625 539 1,240 CPv 236S GW3 246S GW7 247S GW5 252S GW8 258S GW4 266S GW6A 272S GW6B 237P GravelWet3 247P GravelWet7 255P GravelWet5 260P GravelWet4 266P GravelWet8 267P GravelWet6A 273P GravelWet6B Routing Diagram for Eastview2022-postPrepared by Krebs & Lansing Consulting Engineers, Inc., Printed 4/7/2022 HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Subcat Reach Pond Link Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 2HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Project Notes EASTVIEW Old Farm Road & Kimball Avenue South Burlington, Vermont Post Development Stormwater Model Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 3HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Area Listing (selected nodes) Area (acres) CN Description (subcatchment-numbers) 10.430 92 Workbook (236S, 266S) 4.090 85 Workbook (246S) 15.520 87 Workbook (247S) 12.700 82 Workbook (252S) 12.400 90 Workbook (258S, 272S) 55.140 87 TOTAL AREA Type II 24-hr 1 Year Rainfall=1.90"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 4HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Time span=0.00-128.00 hrs, dt=0.01 hrs, 12801 points Runoff by SCS TR-20 method, UH=SCS, Weighted-Q Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=6.550 ac Runoff Depth=1.15"Subcatchment 236S: GW3 Tc=11.3 min CN=92 Runoff=10.97 cfs 0.627 af Runoff Area=4.090 ac Runoff Depth=0.72"Subcatchment 246S: GW7 Tc=6.8 min CN=85 Runoff=5.13 cfs 0.246 af Runoff Area=15.520 ac Runoff Depth=0.83"Subcatchment 247S: GW5 Tc=13.0 min CN=87 Runoff=17.77 cfs 1.071 af Runoff Area=12.700 ac Runoff Depth=0.58"Subcatchment 252S: GW8 Tc=12.5 min CN=82 Runoff=10.04 cfs 0.618 af Runoff Area=7.080 ac Runoff Depth=1.01"Subcatchment 258S: GW4 Tc=7.9 min CN=90 Runoff=11.87 cfs 0.596 af Runoff Area=3.880 ac Runoff Depth=1.15"Subcatchment 266S: GW6A Tc=6.5 min CN=92 Runoff=7.69 cfs 0.371 af Runoff Area=5.320 ac Runoff Depth=1.01"Subcatchment 272S: GW6B Tc=8.7 min CN=90 Runoff=8.67 cfs 0.447 af Peak Elev=374.88' Storage=23,953 cf Inflow=10.97 cfs 0.627 afPond 237P: GravelWet3 Outflow=0.32 cfs 0.627 af Peak Elev=328.49' Storage=16,135 cf Inflow=5.13 cfs 0.246 afPond 247P: GravelWet7 Outflow=0.15 cfs 0.246 af Peak Elev=367.47' Storage=39,509 cf Inflow=17.77 cfs 1.071 afPond 255P: GravelWet5 Outflow=0.39 cfs 1.071 af Peak Elev=382.07' Storage=21,572 cf Inflow=11.87 cfs 0.596 afPond 260P: GravelWet4 Outflow=0.28 cfs 0.596 af Peak Elev=332.36' Storage=25,401 cf Inflow=10.04 cfs 0.618 afPond 266P: GravelWet8 Outflow=0.27 cfs 0.618 af Peak Elev=377.88' Storage=13,628 cf Inflow=7.69 cfs 0.371 afPond 267P: GravelWet6A Outflow=0.18 cfs 0.371 af Peak Elev=334.19' Storage=17,311 cf Inflow=8.67 cfs 0.447 afPond 273P: GravelWet6B Outflow=0.20 cfs 0.447 af Total Runoff Area = 55.140 ac Runoff Volume = 3.976 af Average Runoff Depth = 0.87" Type II 24-hr 1 Year Rainfall=1.90"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 5HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 236S: GW3 Runoff = 10.97 cfs @ 12.03 hrs, Volume= 0.627 af, Depth= 1.15" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Type II 24-hr 1 Year Rainfall=1.90" Area (ac) CN Description * 6.550 92 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 11.3 Direct Entry, Workbook- Lag Subcatchment 236S: GW3 Runoff Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)12 11 10 9 8 7 6 5 4 3 2 1 0 Type II 24-hr 1 Year Rainfall=1.90" Runoff Area=6.550 ac Runoff Volume=0.627 af Runoff Depth=1.15" Tc=11.3 min CN=92 10.97 cfs Type II 24-hr 1 Year Rainfall=1.90"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 6HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 246S: GW7 Runoff = 5.13 cfs @ 11.99 hrs, Volume= 0.246 af, Depth= 0.72" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Type II 24-hr 1 Year Rainfall=1.90" Area (ac) CN Description * 4.090 85 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.8 Direct Entry, Workbook- Lag Subcatchment 246S: GW7 Runoff Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)5 4 3 2 1 0 Type II 24-hr 1 Year Rainfall=1.90" Runoff Area=4.090 ac Runoff Volume=0.246 af Runoff Depth=0.72" Tc=6.8 min CN=85 5.13 cfs Type II 24-hr 1 Year Rainfall=1.90"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 7HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 247S: GW5 Runoff = 17.77 cfs @ 12.06 hrs, Volume= 1.071 af, Depth= 0.83" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Type II 24-hr 1 Year Rainfall=1.90" Area (ac) CN Description * 15.520 87 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 13.0 Direct Entry, Workbook- Lag Subcatchment 247S: GW5 Runoff Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Type II 24-hr 1 Year Rainfall=1.90" Runoff Area=15.520 ac Runoff Volume=1.071 af Runoff Depth=0.83" Tc=13.0 min CN=87 17.77 cfs Type II 24-hr 1 Year Rainfall=1.90"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 8HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 252S: GW8 Runoff = 10.04 cfs @ 12.05 hrs, Volume= 0.618 af, Depth= 0.58" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Type II 24-hr 1 Year Rainfall=1.90" Area (ac) CN Description * 12.700 82 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 12.5 Direct Entry, Workbook- Lag Subcatchment 252S: GW8 Runoff Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)11 10 9 8 7 6 5 4 3 2 1 0 Type II 24-hr 1 Year Rainfall=1.90" Runoff Area=12.700 ac Runoff Volume=0.618 af Runoff Depth=0.58" Tc=12.5 min CN=82 10.04 cfs Type II 24-hr 1 Year Rainfall=1.90"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 9HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 258S: GW4 Runoff = 11.87 cfs @ 12.00 hrs, Volume= 0.596 af, Depth= 1.01" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Type II 24-hr 1 Year Rainfall=1.90" Area (ac) CN Description * 7.080 90 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 7.9 Direct Entry, Workbook- Lag Subcatchment 258S: GW4 Runoff Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)13 12 11 10 9 8 7 6 5 4 3 2 1 0 Type II 24-hr 1 Year Rainfall=1.90" Runoff Area=7.080 ac Runoff Volume=0.596 af Runoff Depth=1.01" Tc=7.9 min CN=90 11.87 cfs Type II 24-hr 1 Year Rainfall=1.90"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 10HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 266S: GW6A Runoff = 7.69 cfs @ 11.98 hrs, Volume= 0.371 af, Depth= 1.15" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Type II 24-hr 1 Year Rainfall=1.90" Area (ac) CN Description * 3.880 92 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.5 Direct Entry, Workbook- Lag Subcatchment 266S: GW6A Runoff Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)8 7 6 5 4 3 2 1 0 Type II 24-hr 1 Year Rainfall=1.90" Runoff Area=3.880 ac Runoff Volume=0.371 af Runoff Depth=1.15" Tc=6.5 min CN=92 7.69 cfs Type II 24-hr 1 Year Rainfall=1.90"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 11HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 272S: GW6B Runoff = 8.67 cfs @ 12.00 hrs, Volume= 0.447 af, Depth= 1.01" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Type II 24-hr 1 Year Rainfall=1.90" Area (ac) CN Description * 5.320 90 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 8.7 Direct Entry, Workbook- Lag Subcatchment 272S: GW6B Runoff Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)9 8 7 6 5 4 3 2 1 0 Type II 24-hr 1 Year Rainfall=1.90" Runoff Area=5.320 ac Runoff Volume=0.447 af Runoff Depth=1.01" Tc=8.7 min CN=90 8.67 cfs Type II 24-hr 1 Year Rainfall=1.90"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 12HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 237P: GravelWet3 Inflow Area = 6.550 ac, Inflow Depth = 1.15" for 1 Year event Inflow = 10.97 cfs @ 12.03 hrs, Volume= 0.627 af Outflow = 0.32 cfs @ 15.18 hrs, Volume= 0.627 af, Atten= 97%, Lag= 189.1 min Primary = 0.32 cfs @ 15.18 hrs, Volume= 0.627 af Routing by Stor-Ind method, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Starting Elev= 372.67' Surf.Area= 14,880 sf Storage= 7,187 cf Peak Elev= 374.88' @ 15.18 hrs Surf.Area= 24,920 sf Storage= 23,953 cf (16,766 cf above start) Plug-Flow detention time= 944.3 min calculated for 0.462 af (74% of inflow) Center-of-Mass det. time= 631.0 min ( 1,450.9 - 819.9 ) Volume Invert Avail.Storage Storage Description #1 370.00' 6,934 cf Custom Stage Data (Prismatic) Listed below (Recalc) 17,335 cf Overall x 40.0% Voids #2 372.33' 498 cf Custom Stage Data (Prismatic) Listed below (Recalc) 4,985 cf Overall x 10.0% Voids #3 373.00' 34,521 cf Custom Stage Data (Prismatic) Listed below (Recalc) 41,953 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 370.00 7,440 0 0 372.33 7,440 17,335 17,335 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 372.33 7,440 0 0 373.00 7,440 4,985 4,985 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 373.00 7,440 0 0 374.00 8,968 8,204 8,204 375.00 10,193 9,581 17,785 376.00 11,474 10,834 28,618 376.50 12,136 5,903 34,521 Device Routing Invert Outlet Devices #1 Primary 372.67'18.0" Round Culvert L= 15.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 372.67' / 371.00' S= 0.1113 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf #2 Device 1 372.67'2.8" Vert. Orifice/Grate C= 0.600 #3 Device 1 373.90'1.0" Vert. Orifice/Grate C= 0.600 #4 Device 1 375.00'48.0" W x 12.0" H Vert. Orifice/Grate C= 0.600 Type II 24-hr 1 Year Rainfall=1.90"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 13HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Primary OutFlow Max=0.32 cfs @ 15.18 hrs HW=374.88' (Free Discharge) 1=Culvert (Passes 0.32 cfs of 8.10 cfs potential flow) 2=Orifice/Grate (Orifice Controls 0.30 cfs @ 6.96 fps) 3=Orifice/Grate (Orifice Controls 0.03 cfs @ 4.65 fps) 4=Orifice/Grate ( Controls 0.00 cfs) Pond 237P: GravelWet3 Inflow Primary Hydrograph Time (hours)12512011511010510095908580757065605550454035302520151050Flow (cfs)12 11 10 9 8 7 6 5 4 3 2 1 0 Inflow Area=6.550 ac Peak Elev=374.88' Storage=23,953 cf 10.97 cfs 0.32 cfs Type II 24-hr 1 Year Rainfall=1.90"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 14HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 247P: GravelWet7 Inflow Area = 4.090 ac, Inflow Depth = 0.72" for 1 Year event Inflow = 5.13 cfs @ 11.99 hrs, Volume= 0.246 af Outflow = 0.15 cfs @ 15.16 hrs, Volume= 0.246 af, Atten= 97%, Lag= 190.2 min Primary = 0.15 cfs @ 15.16 hrs, Volume= 0.246 af Routing by Stor-Ind method, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Starting Elev= 327.67' Surf.Area= 20,916 sf Storage= 10,102 cf Peak Elev= 328.49' @ 15.16 hrs Surf.Area= 33,876 sf Storage= 16,135 cf (6,032 cf above start) Plug-Flow detention time= 1,399.4 min calculated for 0.014 af (6% of inflow) Center-of-Mass det. time= 484.5 min ( 1,334.0 - 849.5 ) Volume Invert Avail.Storage Storage Description #1 325.00' 9,747 cf Custom Stage Data (Prismatic) Listed below (Recalc) 24,367 cf Overall x 40.0% Voids #2 327.33' 701 cf Custom Stage Data (Prismatic) Listed below (Recalc) 7,007 cf Overall x 10.0% Voids #3 328.00' 68,080 cf Custom Stage Data (Prismatic) Listed below (Recalc) 78,528 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 325.00 10,458 0 0 327.33 10,458 24,367 24,367 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 327.33 10,458 0 0 328.00 10,458 7,007 7,007 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 328.00 10,458 0 0 329.00 15,610 13,034 13,034 330.00 17,405 16,508 29,542 331.00 19,255 18,330 47,872 332.00 21,162 20,209 68,080 Device Routing Invert Outlet Devices #1 Primary 327.67'18.0" Round Culvert L= 57.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 327.67' / 327.10' S= 0.0100 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf #2 Device 1 327.67'2.5" Vert. Orifice/Grate C= 0.600 #3 Device 1 328.10'1.0" Vert. Orifice/Grate C= 0.600 #4 Device 1 328.50'6.0" Vert. Orifice/Grate C= 0.600 #5 Device 1 330.50'48.0" W x 6.0" H Vert. Orifice/Grate C= 0.600 #6 Primary 331.00'8.0' long x 4.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 Type II 24-hr 1 Year Rainfall=1.90"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 15HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef. (English) 2.38 2.54 2.69 2.68 2.67 2.67 2.65 2.66 2.66 2.68 2.72 2.73 2.76 2.79 2.88 3.07 3.32 Primary OutFlow Max=0.15 cfs @ 15.16 hrs HW=328.49' (Free Discharge) 1=Culvert (Passes 0.15 cfs of 2.38 cfs potential flow) 2=Orifice/Grate (Orifice Controls 0.14 cfs @ 4.06 fps) 3=Orifice/Grate (Orifice Controls 0.02 cfs @ 2.82 fps) 4=Orifice/Grate ( Controls 0.00 cfs) 5=Orifice/Grate ( Controls 0.00 cfs) 6=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Pond 247P: GravelWet7 InflowPrimary Hydrograph Time (hours)12512011511010510095908580757065605550454035302520151050Flow (cfs)5 4 3 2 1 0 Inflow Area=4.090 ac Peak Elev=328.49' Storage=16,135 cf 5.13 cfs 0.15 cfs Type II 24-hr 1 Year Rainfall=1.90"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 16HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 255P: GravelWet5 Inflow Area = 15.520 ac, Inflow Depth = 0.83" for 1 Year event Inflow = 17.77 cfs @ 12.06 hrs, Volume= 1.071 af Outflow = 0.39 cfs @ 18.26 hrs, Volume= 1.071 af, Atten= 98%, Lag= 372.0 min Primary = 0.39 cfs @ 18.26 hrs, Volume= 1.071 af Routing by Stor-Ind method, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Starting Elev= 364.67' Surf.Area= 17,280 sf Storage= 8,346 cf Peak Elev= 367.47' @ 18.26 hrs Surf.Area= 32,169 sf Storage= 39,509 cf (31,162 cf above start) Plug-Flow detention time= 1,245.7 min calculated for 0.879 af (82% of inflow) Center-of-Mass det. time= 963.5 min ( 1,809.8 - 846.3 ) Volume Invert Avail.Storage Storage Description #1 362.00' 8,052 cf Custom Stage Data (Prismatic) Listed below (Recalc) 20,131 cf Overall x 40.0% Voids #2 364.33' 579 cf Custom Stage Data (Prismatic) Listed below (Recalc) 5,789 cf Overall x 10.0% Voids #3 365.00' 64,384 cf Custom Stage Data (Prismatic) Listed below (Recalc) 73,015 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 362.00 8,640 0 0 364.33 8,640 20,131 20,131 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 364.33 8,640 0 0 365.00 8,640 5,789 5,789 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 365.00 8,640 0 0 366.00 12,649 10,645 10,645 367.00 14,154 13,402 24,046 368.00 15,717 14,936 38,982 369.00 17,336 16,527 55,508 369.50 18,166 8,876 64,384 Device Routing Invert Outlet Devices #1 Primary 364.67'18.0" Round Culvert L= 37.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 364.67' / 358.00' S= 0.1803 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf #2 Device 1 364.67'2.9" Vert. Orifice/Grate C= 0.600 #3 Device 1 365.85'1.0" Vert. Orifice/Grate C= 0.600 #4 Device 1 367.50'48.0" W x 6.0" H Vert. Orifice/Grate C= 0.600 #5 Primary 368.00'8.0' long x 4.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 Type II 24-hr 1 Year Rainfall=1.90"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 17HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef. (English) 2.38 2.54 2.69 2.68 2.67 2.67 2.65 2.66 2.66 2.68 2.72 2.73 2.76 2.79 2.88 3.07 3.32 Primary OutFlow Max=0.39 cfs @ 18.26 hrs HW=367.47' (Free Discharge) 1=Culvert (Passes 0.39 cfs of 9.62 cfs potential flow) 2=Orifice/Grate (Orifice Controls 0.36 cfs @ 7.88 fps) 3=Orifice/Grate (Orifice Controls 0.03 cfs @ 6.05 fps) 4=Orifice/Grate ( Controls 0.00 cfs) 5=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Pond 255P: GravelWet5 InflowPrimary Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Inflow Area=15.520 ac Peak Elev=367.47' Storage=39,509 cf 17.77 cfs 0.39 cfs Type II 24-hr 1 Year Rainfall=1.90"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 18HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 260P: GravelWet4 Inflow Area = 7.080 ac, Inflow Depth = 1.01" for 1 Year event Inflow = 11.87 cfs @ 12.00 hrs, Volume= 0.596 af Outflow = 0.28 cfs @ 15.82 hrs, Volume= 0.596 af, Atten= 98%, Lag= 229.6 min Primary = 0.28 cfs @ 15.82 hrs, Volume= 0.596 af Routing by Stor-Ind method, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Starting Elev= 379.67' Surf.Area= 10,880 sf Storage= 5,255 cf Peak Elev= 382.07' @ 15.82 hrs Surf.Area= 20,519 sf Storage= 21,572 cf (16,317 cf above start) Plug-Flow detention time= 989.6 min calculated for 0.475 af (80% of inflow) Center-of-Mass det. time= 721.9 min ( 1,549.3 - 827.4 ) Volume Invert Avail.Storage Storage Description #1 377.00' 5,070 cf Custom Stage Data (Prismatic) Listed below (Recalc) 12,675 cf Overall x 40.0% Voids #2 379.33' 364 cf Custom Stage Data (Prismatic) Listed below (Recalc) 3,645 cf Overall x 10.0% Voids #3 380.00' 34,618 cf Custom Stage Data (Prismatic) Listed below (Recalc) 40,053 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 377.00 5,440 0 0 379.33 5,440 12,675 12,675 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 379.33 5,440 0 0 380.00 5,440 3,645 3,645 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 380.00 5,440 0 0 381.00 8,025 6,733 6,733 382.00 9,537 8,781 15,514 383.00 11,105 10,321 25,835 383.75 12,318 8,784 34,618 Device Routing Invert Outlet Devices #1 Primary 379.67'18.0" Round Culvert L= 15.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 379.67' / 378.00' S= 0.1113 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf #2 Device 1 379.67'2.5" Vert. Orifice/Grate C= 0.600 #3 Device 1 380.95'1.0" Vert. Orifice/Grate C= 0.600 #4 Device 1 382.50'48.0" W x 6.0" H Vert. Orifice/Grate C= 0.600 #5 Primary 383.00'8.0' long x 4.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Type II 24-hr 1 Year Rainfall=1.90"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 19HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Coef. (English) 2.38 2.54 2.69 2.68 2.67 2.67 2.65 2.66 2.66 2.68 2.72 2.73 2.76 2.79 2.88 3.07 3.32 Primary OutFlow Max=0.28 cfs @ 15.82 hrs HW=382.07' (Free Discharge) 1=Culvert (Passes 0.28 cfs of 8.62 cfs potential flow) 2=Orifice/Grate (Orifice Controls 0.25 cfs @ 7.29 fps) 3=Orifice/Grate (Orifice Controls 0.03 cfs @ 4.99 fps) 4=Orifice/Grate ( Controls 0.00 cfs) 5=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Pond 260P: GravelWet4 InflowPrimary Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)13 12 11 10 9 8 7 6 5 4 3 2 1 0 Inflow Area=7.080 ac Peak Elev=382.07' Storage=21,572 cf 11.87 cfs 0.28 cfs Type II 24-hr 1 Year Rainfall=1.90"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 20HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 266P: GravelWet8 Inflow Area = 12.700 ac, Inflow Depth = 0.58" for 1 Year event Inflow = 10.04 cfs @ 12.05 hrs, Volume= 0.618 af Outflow = 0.27 cfs @ 18.13 hrs, Volume= 0.618 af, Atten= 97%, Lag= 364.5 min Primary = 0.27 cfs @ 18.13 hrs, Volume= 0.618 af Routing by Stor-Ind method, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Starting Elev= 330.67' Surf.Area= 18,000 sf Storage= 8,694 cf Peak Elev= 332.36' @ 18.13 hrs Surf.Area= 32,330 sf Storage= 25,401 cf (16,707 cf above start) Plug-Flow detention time= 1,194.6 min calculated for 0.418 af (68% of inflow) Center-of-Mass det. time= 769.2 min ( 1,637.2 - 868.1 ) Volume Invert Avail.Storage Storage Description #1 328.00' 8,388 cf Custom Stage Data (Prismatic) Listed below (Recalc) 20,970 cf Overall x 40.0% Voids #2 330.33' 603 cf Custom Stage Data (Prismatic) Listed below (Recalc) 6,030 cf Overall x 10.0% Voids #3 331.00' 51,235 cf Custom Stage Data (Prismatic) Listed below (Recalc) 60,226 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 328.00 9,000 0 0 330.33 9,000 20,970 20,970 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 330.33 9,000 0 0 331.00 9,000 6,030 6,030 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 331.00 9,000 0 0 332.00 13,677 11,339 11,339 333.00 15,480 14,579 25,917 334.00 17,340 16,410 42,327 334.50 18,291 8,908 51,235 Device Routing Invert Outlet Devices #1 Primary 330.67'18.0" Round Culvert L= 40.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 330.67' / 330.35' S= 0.0080 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf #2 Device 1 330.67'2.7" Vert. Orifice/Grate C= 0.600 #3 Device 1 331.20'1.0" Vert. Orifice/Grate C= 0.600 #4 Device 1 332.40'6.0" Vert. Orifice/Grate C= 0.600 #5 Device 1 333.00'48.0" W x 6.0" H Vert. Orifice/Grate C= 0.600 #6 Primary 333.50'8.0' long x 4.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 Type II 24-hr 1 Year Rainfall=1.90"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 21HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef. (English) 2.38 2.54 2.69 2.68 2.67 2.67 2.65 2.66 2.66 2.68 2.72 2.73 2.76 2.79 2.88 3.07 3.32 Primary OutFlow Max=0.27 cfs @ 18.13 hrs HW=332.36' (Free Discharge) 1=Culvert (Passes 0.27 cfs of 6.52 cfs potential flow) 2=Orifice/Grate (Orifice Controls 0.24 cfs @ 6.05 fps) 3=Orifice/Grate (Orifice Controls 0.03 cfs @ 5.10 fps) 4=Orifice/Grate ( Controls 0.00 cfs) 5=Orifice/Grate ( Controls 0.00 cfs) 6=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Pond 266P: GravelWet8 InflowPrimary Hydrograph Time (hours)12512011511010510095908580757065605550454035302520151050Flow (cfs)11 10 9 8 7 6 5 4 3 2 1 0 Inflow Area=12.700 ac Peak Elev=332.36' Storage=25,401 cf 10.04 cfs 0.27 cfs Type II 24-hr 1 Year Rainfall=1.90"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 22HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 267P: GravelWet6A Inflow Area = 3.880 ac, Inflow Depth = 1.15" for 1 Year event Inflow = 7.69 cfs @ 11.98 hrs, Volume= 0.371 af Outflow = 0.18 cfs @ 15.40 hrs, Volume= 0.371 af, Atten= 98%, Lag= 205.1 min Primary = 0.18 cfs @ 15.40 hrs, Volume= 0.371 af Routing by Stor-Ind method, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Starting Elev= 375.67' Surf.Area= 7,300 sf Storage= 3,526 cf Peak Elev= 377.88' @ 15.40 hrs Surf.Area= 13,781 sf Storage= 13,628 cf (10,102 cf above start) Plug-Flow detention time= 966.4 min calculated for 0.290 af (78% of inflow) Center-of-Mass det. time= 686.8 min ( 1,502.2 - 815.4 ) Volume Invert Avail.Storage Storage Description #1 373.00' 3,402 cf Custom Stage Data (Prismatic) Listed below (Recalc) 8,504 cf Overall x 40.0% Voids #2 375.33' 245 cf Custom Stage Data (Prismatic) Listed below (Recalc) 2,446 cf Overall x 10.0% Voids #3 376.00' 21,800 cf Custom Stage Data (Prismatic) Listed below (Recalc) 25,446 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 373.00 3,650 0 0 375.33 3,650 8,504 8,504 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 375.33 3,650 0 0 376.00 3,650 2,446 2,446 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 376.00 3,650 0 0 377.00 5,622 4,636 4,636 378.00 6,595 6,109 10,745 379.00 7,624 7,110 17,854 379.50 8,160 3,946 21,800 Device Routing Invert Outlet Devices #1 Primary 375.67'18.0" Round Culvert L= 90.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 375.67' / 370.00' S= 0.0630 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf #2 Device 1 375.67'2.0" Vert. Orifice/Grate C= 0.600 #3 Device 1 376.90'1.0" Vert. Orifice/Grate C= 0.600 #4 Device 1 377.90'48.0" x 6.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Type II 24-hr 1 Year Rainfall=1.90"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 23HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Primary OutFlow Max=0.18 cfs @ 15.40 hrs HW=377.88' (Free Discharge) 1=Culvert (Passes 0.18 cfs of 8.13 cfs potential flow) 2=Orifice/Grate (Orifice Controls 0.15 cfs @ 7.03 fps) 3=Orifice/Grate (Orifice Controls 0.03 cfs @ 4.67 fps) 4=Orifice/Grate ( Controls 0.00 cfs) Pond 267P: GravelWet6A Inflow Primary Hydrograph Time (hours)12512011511010510095908580757065605550454035302520151050Flow (cfs)8 7 6 5 4 3 2 1 0 Inflow Area=3.880 ac Peak Elev=377.88' Storage=13,628 cf 7.69 cfs 0.18 cfs Type II 24-hr 1 Year Rainfall=1.90"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 24HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 273P: GravelWet6B Inflow Area = 5.320 ac, Inflow Depth = 1.01" for 1 Year event Inflow = 8.67 cfs @ 12.00 hrs, Volume= 0.447 af Outflow = 0.20 cfs @ 15.94 hrs, Volume= 0.447 af, Atten= 98%, Lag= 236.1 min Primary = 0.20 cfs @ 15.94 hrs, Volume= 0.447 af Routing by Stor-Ind method, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Starting Elev= 332.17' Surf.Area= 10,260 sf Storage= 4,956 cf Peak Elev= 334.19' @ 15.94 hrs Surf.Area= 18,930 sf Storage= 17,311 cf (12,355 cf above start) Plug-Flow detention time= 1,086.5 min calculated for 0.334 af (75% of inflow) Center-of-Mass det. time= 751.2 min ( 1,579.3 - 828.1 ) Volume Invert Avail.Storage Storage Description #1 329.50' 4,781 cf Custom Stage Data (Prismatic) Listed below (Recalc) 11,953 cf Overall x 40.0% Voids #2 331.83' 344 cf Custom Stage Data (Prismatic) Listed below (Recalc) 3,437 cf Overall x 10.0% Voids #3 332.50' 30,552 cf Custom Stage Data (Prismatic) Listed below (Recalc) 35,677 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 329.50 5,130 0 0 331.83 5,130 11,953 11,953 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 331.83 5,130 0 0 332.50 5,130 3,437 3,437 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 332.50 5,130 0 0 333.00 6,813 2,986 2,986 334.00 8,365 7,589 10,575 335.00 9,975 9,170 19,745 336.00 11,640 10,808 30,552 Device Routing Invert Outlet Devices #1 Primary 332.17'24.0" Round Culvert L= 284.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 332.17' / 330.75' S= 0.0050 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 3.14 sf #2 Device 1 332.17'2.2" Vert. Orifice/Grate C= 0.600 #3 Device 1 333.25'1.0" Vert. Orifice/Grate C= 0.600 #4 Device 1 334.20'48.0" W x 6.0" H Vert. Orifice/Grate C= 0.600 Type II 24-hr 1 Year Rainfall=1.90"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 25HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Primary OutFlow Max=0.20 cfs @ 15.94 hrs HW=334.19' (Free Discharge) 1=Culvert (Passes 0.20 cfs of 12.06 cfs potential flow) 2=Orifice/Grate (Orifice Controls 0.18 cfs @ 6.68 fps) 3=Orifice/Grate (Orifice Controls 0.02 cfs @ 4.56 fps) 4=Orifice/Grate ( Controls 0.00 cfs) Pond 273P: GravelWet6B Inflow Primary Hydrograph Time (hours)12512011511010510095908580757065605550454035302520151050Flow (cfs)9 8 7 6 5 4 3 2 1 0 Inflow Area=5.320 ac Peak Elev=334.19' Storage=17,311 cf 8.67 cfs 0.20 cfs 2022 Application 17S GW3-Pre 18S GW4-Pre 19S GW5-Pre 20S GW6A-Pre 21S GW6B-Pre 22S GW7-Pre 23S GW8-Pre 18L SN4 19L SN6 20L SN7 21L SN8 22L SN9 23L SN10 Routing Diagram for Eastview2022-prePrepared by Krebs & Lansing Consulting Engineers, Inc., Printed 4/6/2022 HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Subcat Reach Pond Link Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 2HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Project Notes Eastview Pre Development Stormwater Model Qp10 & Qp100 Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 3HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Area Listing (selected nodes) Area (acres) CN Description (subcatchment-numbers) 29.150 78 Workbook (17S, 18S, 19S) 25.990 77 Workbook (20S, 21S, 22S, 23S) 55.140 78 TOTAL AREA Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 4HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Time span=5.00-48.00 hrs, dt=0.05 hrs, 861 points Runoff by SCS TR-20 method, UH=SCS, Weighted-Q Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=6.550 ac Runoff Depth=1.31"Subcatchment 17S: GW3-Pre Tc=18.9 min CN=78 Runoff=9.63 cfs 0.715 af Runoff Area=7.080 ac Runoff Depth=1.31"Subcatchment 18S: GW4-Pre Tc=12.0 min CN=78 Runoff=13.08 cfs 0.773 af Runoff Area=15.520 ac Runoff Depth=1.31"Subcatchment 19S: GW5-Pre Tc=17.3 min CN=78 Runoff=23.99 cfs 1.694 af Runoff Area=3.880 ac Runoff Depth=1.25"Subcatchment 20S: GW6A-Pre Tc=10.9 min CN=77 Runoff=7.06 cfs 0.403 af Runoff Area=5.320 ac Runoff Depth=1.25"Subcatchment 21S: GW6B-Pre Tc=13.6 min CN=77 Runoff=8.81 cfs 0.553 af Runoff Area=4.090 ac Runoff Depth=1.25"Subcatchment 22S: GW7-Pre Tc=8.7 min CN=77 Runoff=8.09 cfs 0.425 af Runoff Area=12.700 ac Runoff Depth=1.25"Subcatchment 23S: GW8-Pre Tc=14.8 min CN=77 Runoff=20.09 cfs 1.320 af Inflow=9.63 cfs 0.715 afLink 18L: SN4 Primary=9.63 cfs 0.715 af Inflow=13.08 cfs 0.773 afLink 19L: SN6 Primary=13.08 cfs 0.773 af Inflow=23.99 cfs 1.694 afLink 20L: SN7 Primary=23.99 cfs 1.694 af Inflow=15.72 cfs 0.957 afLink 21L: SN8 Primary=15.72 cfs 0.957 af Inflow=8.09 cfs 0.425 afLink 22L: SN9 Primary=8.09 cfs 0.425 af Inflow=20.09 cfs 1.320 afLink 23L: SN10 Primary=20.09 cfs 1.320 af Total Runoff Area = 55.140 ac Runoff Volume = 5.885 af Average Runoff Depth = 1.28" Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 5HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 17S: GW3-Pre Area to 24" Culvert on Kennedy Drive east of Windridge Runoff = 9.63 cfs @ 12.12 hrs, Volume= 0.715 af, Depth= 1.31" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 5.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 10 Year Rainfall=3.25" Area (ac) CN Description * 6.550 78 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 18.9 Direct Entry, Workbook-Lag Subcatchment 17S: GW3-Pre Runoff Hydrograph Time (hours)48474645444342414039383736353433323130292827262524232221201918171615141312111098765Flow (cfs)10 9 8 7 6 5 4 3 2 1 0 Type II 24-hr 10 Year Rainfall=3.25" Runoff Area=6.550 ac Runoff Volume=0.715 af Runoff Depth=1.31" Tc=18.9 min CN=78 9.63 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 6HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 18S: GW4-Pre Area to 24" Culvert on Kennedy Drive east of Windridge Runoff = 13.08 cfs @ 12.04 hrs, Volume= 0.773 af, Depth= 1.31" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 5.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 10 Year Rainfall=3.25" Area (ac) CN Description * 7.080 78 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 12.0 Direct Entry, Workbook-Lag Subcatchment 18S: GW4-Pre Runoff Hydrograph Time (hours)48474645444342414039383736353433323130292827262524232221201918171615141312111098765Flow (cfs)14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Type II 24-hr 10 Year Rainfall=3.25" Runoff Area=7.080 ac Runoff Volume=0.773 af Runoff Depth=1.31" Tc=12.0 min CN=78 13.08 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 7HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 19S: GW5-Pre Area to 24" Culvert on Kennedy Drive east of Windridge Runoff = 23.99 cfs @ 12.10 hrs, Volume= 1.694 af, Depth= 1.31" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 5.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 10 Year Rainfall=3.25" Area (ac) CN Description * 15.520 78 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 17.3 Direct Entry, Workbook-Lag Subcatchment 19S: GW5-Pre Runoff Hydrograph Time (hours)48474645444342414039383736353433323130292827262524232221201918171615141312111098765Flow (cfs)26 24 22 20 18 16 14 12 10 8 6 4 2 0 Type II 24-hr 10 Year Rainfall=3.25" Runoff Area=15.520 ac Runoff Volume=1.694 af Runoff Depth=1.31" Tc=17.3 min CN=78 23.99 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 8HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 20S: GW6A-Pre Area to 24" Culvert on Kennedy Drive east of Windridge Runoff = 7.06 cfs @ 12.03 hrs, Volume= 0.403 af, Depth= 1.25" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 5.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 10 Year Rainfall=3.25" Area (ac) CN Description * 3.880 77 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.9 Direct Entry, Workbook-Lag Subcatchment 20S: GW6A-Pre Runoff Hydrograph Time (hours)48474645444342414039383736353433323130292827262524232221201918171615141312111098765Flow (cfs)7 6 5 4 3 2 1 0 Type II 24-hr 10 Year Rainfall=3.25" Runoff Area=3.880 ac Runoff Volume=0.403 af Runoff Depth=1.25" Tc=10.9 min CN=77 7.06 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 9HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 21S: GW6B-Pre Area to 24" Culvert on Kennedy Drive east of Windridge Runoff = 8.81 cfs @ 12.06 hrs, Volume= 0.553 af, Depth= 1.25" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 5.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 10 Year Rainfall=3.25" Area (ac) CN Description * 5.320 77 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 13.6 Direct Entry, Workbook-Lag Subcatchment 21S: GW6B-Pre Runoff Hydrograph Time (hours)48474645444342414039383736353433323130292827262524232221201918171615141312111098765Flow (cfs)9 8 7 6 5 4 3 2 1 0 Type II 24-hr 10 Year Rainfall=3.25" Runoff Area=5.320 ac Runoff Volume=0.553 af Runoff Depth=1.25" Tc=13.6 min CN=77 8.81 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 10HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 22S: GW7-Pre Area to 24" Culvert on Kennedy Drive east of Windridge Runoff = 8.09 cfs @ 12.01 hrs, Volume= 0.425 af, Depth= 1.25" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 5.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 10 Year Rainfall=3.25" Area (ac) CN Description * 4.090 77 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 8.7 Direct Entry, Workbook-Lag Subcatchment 22S: GW7-Pre Runoff Hydrograph Time (hours)48474645444342414039383736353433323130292827262524232221201918171615141312111098765Flow (cfs)9 8 7 6 5 4 3 2 1 0 Type II 24-hr 10 Year Rainfall=3.25" Runoff Area=4.090 ac Runoff Volume=0.425 af Runoff Depth=1.25" Tc=8.7 min CN=77 8.09 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 11HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 23S: GW8-Pre Area to 24" Culvert on Kennedy Drive east of Windridge Runoff = 20.09 cfs @ 12.08 hrs, Volume= 1.320 af, Depth= 1.25" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 5.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 10 Year Rainfall=3.25" Area (ac) CN Description * 12.700 77 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 14.8 Direct Entry, Workbook-Lag Subcatchment 23S: GW8-Pre Runoff Hydrograph Time (hours)48474645444342414039383736353433323130292827262524232221201918171615141312111098765Flow (cfs)22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Type II 24-hr 10 Year Rainfall=3.25" Runoff Area=12.700 ac Runoff Volume=1.320 af Runoff Depth=1.25" Tc=14.8 min CN=77 20.09 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 12HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Link 18L: SN4 Inflow Area = 6.550 ac, Inflow Depth = 1.31" for 10 Year event Inflow = 9.63 cfs @ 12.12 hrs, Volume= 0.715 af Primary = 9.63 cfs @ 12.12 hrs, Volume= 0.715 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-48.00 hrs, dt= 0.05 hrs Link 18L: SN4 Inflow Primary Hydrograph Time (hours) 484644424038363432302826242220181614121086Flow (cfs)10 9 8 7 6 5 4 3 2 1 0 Inflow Area=6.550 ac 9.63 cfs9.63 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 13HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Link 19L: SN6 Inflow Area = 7.080 ac, Inflow Depth = 1.31" for 10 Year event Inflow = 13.08 cfs @ 12.04 hrs, Volume= 0.773 af Primary = 13.08 cfs @ 12.04 hrs, Volume= 0.773 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-48.00 hrs, dt= 0.05 hrs Link 19L: SN6 Inflow Primary Hydrograph Time (hours) 484644424038363432302826242220181614121086Flow (cfs)14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Inflow Area=7.080 ac 13.08 cfs13.08 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 14HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Link 20L: SN7 Inflow Area = 15.520 ac, Inflow Depth = 1.31" for 10 Year event Inflow = 23.99 cfs @ 12.10 hrs, Volume= 1.694 af Primary = 23.99 cfs @ 12.10 hrs, Volume= 1.694 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-48.00 hrs, dt= 0.05 hrs Link 20L: SN7 Inflow Primary Hydrograph Time (hours) 484644424038363432302826242220181614121086Flow (cfs)26 24 22 20 18 16 14 12 10 8 6 4 2 0 Inflow Area=15.520 ac 23.99 cfs23.99 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 15HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Link 21L: SN8 Inflow Area = 9.200 ac, Inflow Depth = 1.25" for 10 Year event Inflow = 15.72 cfs @ 12.05 hrs, Volume= 0.957 af Primary = 15.72 cfs @ 12.05 hrs, Volume= 0.957 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-48.00 hrs, dt= 0.05 hrs Link 21L: SN8 Inflow Primary Hydrograph Time (hours) 484644424038363432302826242220181614121086Flow (cfs)17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Inflow Area=9.200 ac 15.72 cfs15.72 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 16HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Link 22L: SN9 Inflow Area = 4.090 ac, Inflow Depth = 1.25" for 10 Year event Inflow = 8.09 cfs @ 12.01 hrs, Volume= 0.425 af Primary = 8.09 cfs @ 12.01 hrs, Volume= 0.425 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-48.00 hrs, dt= 0.05 hrs Link 22L: SN9 Inflow Primary Hydrograph Time (hours) 484644424038363432302826242220181614121086Flow (cfs)9 8 7 6 5 4 3 2 1 0 Inflow Area=4.090 ac 8.09 cfs8.09 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 17HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Link 23L: SN10 Inflow Area = 12.700 ac, Inflow Depth = 1.25" for 10 Year event Inflow = 20.09 cfs @ 12.08 hrs, Volume= 1.320 af Primary = 20.09 cfs @ 12.08 hrs, Volume= 1.320 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-48.00 hrs, dt= 0.05 hrs Link 23L: SN10 Inflow Primary Hydrograph Time (hours) 484644424038363432302826242220181614121086Flow (cfs)22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Inflow Area=12.700 ac 20.09 cfs20.09 cfs Qp10 239S GW3 248S GW7 249S GW5 257S GW8 261S GW4 268S GW6A 274S GW6B 240P GravelWet3 249P GravelWet7 253P GravelWet5 262P GravelWet4 264P GravelWet8 269P GravelWet6A 275P GravelWet6B 250L SN004 251L SN006 252L SN007 253L SN008 254L SN009 255L SN010 Routing Diagram for Eastview2022-postPrepared by Krebs & Lansing Consulting Engineers, Inc., Printed 4/7/2022 HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Subcat Reach Pond Link Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 2HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Project Notes EASTVIEW Old Farm Road & Kimball Avenue South Burlington, Vermont Post Development Stormwater Model Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 3HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Area Listing (selected nodes) Area (acres) CN Description (subcatchment-numbers) 10.430 91 Workbook (239S, 268S) 4.090 85 Workbook (248S) 15.520 86 Workbook (249S) 12.700 82 Workbook (257S) 12.400 89 Workbook (261S, 274S) 55.140 87 TOTAL AREA Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 4HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Time span=0.00-128.00 hrs, dt=0.01 hrs, 12801 points Runoff by SCS TR-20 method, UH=SCS, Weighted-Q Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=6.550 ac Runoff Depth=2.31"Subcatchment 239S: GW3 Tc=11.8 min CN=91 Runoff=21.20 cfs 1.258 af Runoff Area=4.090 ac Runoff Depth=1.80"Subcatchment 248S: GW7 Tc=6.8 min CN=85 Runoff=12.69 cfs 0.614 af Runoff Area=15.520 ac Runoff Depth=1.88"Subcatchment 249S: GW5 Tc=13.4 min CN=86 Runoff=39.77 cfs 2.430 af Runoff Area=12.700 ac Runoff Depth=1.58"Subcatchment 257S: GW8 Tc=12.7 min CN=82 Runoff=28.07 cfs 1.670 af Runoff Area=7.080 ac Runoff Depth=2.13"Subcatchment 261S: GW4 Tc=8.3 min CN=89 Runoff=24.15 cfs 1.255 af Runoff Area=3.880 ac Runoff Depth=2.31"Subcatchment 268S: GW6A Tc=6.8 min CN=91 Runoff=14.86 cfs 0.745 af Runoff Area=5.320 ac Runoff Depth=2.13"Subcatchment 274S: GW6B Tc=9.1 min CN=89 Runoff=17.65 cfs 0.943 af Peak Elev=375.65' Storage=32,058 cf Inflow=21.20 cfs 1.258 afPond 240P: GravelWet3 Outflow=7.04 cfs 1.258 af Peak Elev=329.05' Storage=24,229 cf Inflow=12.69 cfs 0.614 afPond 249P: GravelWet7 Outflow=0.73 cfs 0.614 af Peak Elev=368.41' Storage=54,118 cf Inflow=39.77 cfs 2.430 afPond 253P: GravelWet5 Outflow=13.45 cfs 2.430 af Peak Elev=382.86' Storage=29,702 cf Inflow=24.15 cfs 1.255 afPond 262P: GravelWet4 Outflow=7.11 cfs 1.255 af Peak Elev=333.44' Storage=41,964 cf Inflow=28.07 cfs 1.670 afPond 264P: GravelWet8 Outflow=5.00 cfs 1.670 af Peak Elev=378.51' Storage=17,889 cf Inflow=14.86 cfs 0.745 afPond 269P: GravelWet6A Outflow=5.85 cfs 0.745 af Peak Elev=334.81' Storage=23,039 cf Inflow=17.65 cfs 0.943 afPond 275P: GravelWet6B Outflow=5.91 cfs 0.943 af Inflow=7.04 cfs 1.258 afLink 250L: SN004 Primary=7.04 cfs 1.258 af Inflow=7.11 cfs 1.255 afLink 251L: SN006 Primary=7.11 cfs 1.255 af Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 5HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Inflow=13.45 cfs 2.430 afLink 252L: SN007 Primary=13.45 cfs 2.430 af Inflow=11.50 cfs 1.688 afLink 253L: SN008 Primary=11.50 cfs 1.688 af Inflow=0.73 cfs 0.614 afLink 254L: SN009 Primary=0.73 cfs 0.614 af Inflow=5.00 cfs 1.670 afLink 255L: SN010 Primary=5.00 cfs 1.670 af Total Runoff Area = 55.140 ac Runoff Volume = 8.916 af Average Runoff Depth = 1.94" Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 6HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 239S: GW3 Runoff = 21.20 cfs @ 12.03 hrs, Volume= 1.258 af, Depth= 2.31" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Type II 24-hr 10 Year Rainfall=3.25" Area (ac) CN Description * 6.550 91 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 11.8 Direct Entry, Workbook- Lag Subcatchment 239S: GW3 Runoff Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Type II 24-hr 10 Year Rainfall=3.25" Runoff Area=6.550 ac Runoff Volume=1.258 af Runoff Depth=2.31" Tc=11.8 min CN=91 21.20 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 7HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 248S: GW7 Runoff = 12.69 cfs @ 11.98 hrs, Volume= 0.614 af, Depth= 1.80" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Type II 24-hr 10 Year Rainfall=3.25" Area (ac) CN Description * 4.090 85 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.8 Direct Entry, Workbook- Lag Subcatchment 248S: GW7 Runoff Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Type II 24-hr 10 Year Rainfall=3.25" Runoff Area=4.090 ac Runoff Volume=0.614 af Runoff Depth=1.80" Tc=6.8 min CN=85 12.69 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 8HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 249S: GW5 Runoff = 39.77 cfs @ 12.05 hrs, Volume= 2.430 af, Depth= 1.88" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Type II 24-hr 10 Year Rainfall=3.25" Area (ac) CN Description * 15.520 86 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 13.4 Direct Entry, Workbook- Lag Subcatchment 249S: GW5 Runoff Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)44 42 40 38 36 34 32 30 28 26 24 22 20 18 16 14 12 10 8 6 4 2 0 Type II 24-hr 10 Year Rainfall=3.25" Runoff Area=15.520 ac Runoff Volume=2.430 af Runoff Depth=1.88" Tc=13.4 min CN=86 39.77 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 9HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 257S: GW8 Runoff = 28.07 cfs @ 12.05 hrs, Volume= 1.670 af, Depth= 1.58" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Type II 24-hr 10 Year Rainfall=3.25" Area (ac) CN Description * 12.700 82 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 12.7 Direct Entry, Workbook- Lag Subcatchment 257S: GW8 Runoff Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)30 28 26 24 22 20 18 16 14 12 10 8 6 4 2 0 Type II 24-hr 10 Year Rainfall=3.25" Runoff Area=12.700 ac Runoff Volume=1.670 af Runoff Depth=1.58" Tc=12.7 min CN=82 28.07 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 10HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 261S: GW4 Runoff = 24.15 cfs @ 12.00 hrs, Volume= 1.255 af, Depth= 2.13" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Type II 24-hr 10 Year Rainfall=3.25" Area (ac) CN Description * 7.080 89 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 8.3 Direct Entry, Workbook- Lag Subcatchment 261S: GW4 Runoff Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)26 24 22 20 18 16 14 12 10 8 6 4 2 0 Type II 24-hr 10 Year Rainfall=3.25" Runoff Area=7.080 ac Runoff Volume=1.255 af Runoff Depth=2.13" Tc=8.3 min CN=89 24.15 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 11HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 268S: GW6A Runoff = 14.86 cfs @ 11.98 hrs, Volume= 0.745 af, Depth= 2.31" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Type II 24-hr 10 Year Rainfall=3.25" Area (ac) CN Description * 3.880 91 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.8 Direct Entry, Workbook- Lag Subcatchment 268S: GW6A Runoff Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Type II 24-hr 10 Year Rainfall=3.25" Runoff Area=3.880 ac Runoff Volume=0.745 af Runoff Depth=2.31" Tc=6.8 min CN=91 14.86 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 12HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 274S: GW6B Runoff = 17.65 cfs @ 12.00 hrs, Volume= 0.943 af, Depth= 2.13" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Type II 24-hr 10 Year Rainfall=3.25" Area (ac) CN Description * 5.320 89 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 9.1 Direct Entry, Workbook- Lag Subcatchment 274S: GW6B Runoff Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Type II 24-hr 10 Year Rainfall=3.25" Runoff Area=5.320 ac Runoff Volume=0.943 af Runoff Depth=2.13" Tc=9.1 min CN=89 17.65 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 13HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 240P: GravelWet3 Inflow Area = 6.550 ac, Inflow Depth = 2.31" for 10 Year event Inflow = 21.20 cfs @ 12.03 hrs, Volume= 1.258 af Outflow = 7.04 cfs @ 12.22 hrs, Volume= 1.258 af, Atten= 67%, Lag= 11.3 min Primary = 7.04 cfs @ 12.22 hrs, Volume= 1.258 af Routing by Stor-Ind method, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Starting Elev= 372.67' Surf.Area= 14,880 sf Storage= 7,187 cf Peak Elev= 375.65' @ 12.22 hrs Surf.Area= 25,899 sf Storage= 32,058 cf (24,871 cf above start) Plug-Flow detention time= 570.9 min calculated for 1.093 af (87% of inflow) Center-of-Mass det. time= 426.2 min ( 1,230.3 - 804.2 ) Volume Invert Avail.Storage Storage Description #1 370.00' 6,934 cf Custom Stage Data (Prismatic) Listed below (Recalc) 17,335 cf Overall x 40.0% Voids #2 372.33' 498 cf Custom Stage Data (Prismatic) Listed below (Recalc) 4,985 cf Overall x 10.0% Voids #3 373.00' 34,521 cf Custom Stage Data (Prismatic) Listed below (Recalc) 41,953 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 370.00 7,440 0 0 372.33 7,440 17,335 17,335 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 372.33 7,440 0 0 373.00 7,440 4,985 4,985 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 373.00 7,440 0 0 374.00 8,968 8,204 8,204 375.00 10,193 9,581 17,785 376.00 11,474 10,834 28,618 376.50 12,136 5,903 34,521 Device Routing Invert Outlet Devices #1 Primary 372.67'18.0" Round Culvert L= 15.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 372.67' / 371.00' S= 0.1113 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf #2 Device 1 372.67'2.8" Vert. Orifice/Grate C= 0.600 #3 Device 1 373.90'1.0" Vert. Orifice/Grate C= 0.600 #4 Device 1 375.00'48.0" W x 12.0" H Vert. Orifice/Grate C= 0.600 Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 14HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Primary OutFlow Max=7.03 cfs @ 12.22 hrs HW=375.65' (Free Discharge) 1=Culvert (Passes 7.03 cfs of 10.02 cfs potential flow) 2=Orifice/Grate (Orifice Controls 0.35 cfs @ 8.14 fps) 3=Orifice/Grate (Orifice Controls 0.03 cfs @ 6.28 fps) 4=Orifice/Grate (Orifice Controls 6.65 cfs @ 2.58 fps) Pond 240P: GravelWet3 Inflow Primary Hydrograph Time (hours)12512011511010510095908580757065605550454035302520151050Flow (cfs)23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Inflow Area=6.550 ac Peak Elev=375.65' Storage=32,058 cf 21.20 cfs 7.04 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 15HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 249P: GravelWet7 Inflow Area = 4.090 ac, Inflow Depth = 1.80" for 10 Year event Inflow = 12.69 cfs @ 11.98 hrs, Volume= 0.614 af Outflow = 0.73 cfs @ 12.97 hrs, Volume= 0.614 af, Atten= 94%, Lag= 59.1 min Primary = 0.73 cfs @ 12.97 hrs, Volume= 0.614 af Routing by Stor-Ind method, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Starting Elev= 327.67' Surf.Area= 20,916 sf Storage= 10,102 cf Peak Elev= 329.05' @ 12.97 hrs Surf.Area= 36,612 sf Storage= 24,229 cf (14,127 cf above start) Plug-Flow detention time= 777.5 min calculated for 0.382 af (62% of inflow) Center-of-Mass det. time= 413.5 min ( 1,236.5 - 823.0 ) Volume Invert Avail.Storage Storage Description #1 325.00' 9,747 cf Custom Stage Data (Prismatic) Listed below (Recalc) 24,367 cf Overall x 40.0% Voids #2 327.33' 701 cf Custom Stage Data (Prismatic) Listed below (Recalc) 7,007 cf Overall x 10.0% Voids #3 328.00' 68,080 cf Custom Stage Data (Prismatic) Listed below (Recalc) 78,528 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 325.00 10,458 0 0 327.33 10,458 24,367 24,367 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 327.33 10,458 0 0 328.00 10,458 7,007 7,007 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 328.00 10,458 0 0 329.00 15,610 13,034 13,034 330.00 17,405 16,508 29,542 331.00 19,255 18,330 47,872 332.00 21,162 20,209 68,080 Device Routing Invert Outlet Devices #1 Primary 327.67'18.0" Round Culvert L= 57.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 327.67' / 327.10' S= 0.0100 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf #2 Device 1 327.67'2.5" Vert. Orifice/Grate C= 0.600 #3 Device 1 328.10'1.0" Vert. Orifice/Grate C= 0.600 #4 Device 1 328.50'6.0" Vert. Orifice/Grate C= 0.600 #5 Device 1 330.50'48.0" W x 6.0" H Vert. Orifice/Grate C= 0.600 #6 Primary 331.00'8.0' long x 4.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 16HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef. (English) 2.38 2.54 2.69 2.68 2.67 2.67 2.65 2.66 2.66 2.68 2.72 2.73 2.76 2.79 2.88 3.07 3.32 Primary OutFlow Max=0.73 cfs @ 12.97 hrs HW=329.05' (Free Discharge) 1=Culvert (Passes 0.73 cfs of 5.36 cfs potential flow) 2=Orifice/Grate (Orifice Controls 0.19 cfs @ 5.43 fps) 3=Orifice/Grate (Orifice Controls 0.02 cfs @ 4.58 fps) 4=Orifice/Grate (Orifice Controls 0.52 cfs @ 2.63 fps) 5=Orifice/Grate ( Controls 0.00 cfs) 6=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Pond 249P: GravelWet7 InflowPrimary Hydrograph Time (hours)12512011511010510095908580757065605550454035302520151050Flow (cfs)14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Inflow Area=4.090 ac Peak Elev=329.05' Storage=24,229 cf 12.69 cfs 0.73 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 17HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 253P: GravelWet5 Inflow Area = 15.520 ac, Inflow Depth = 1.88" for 10 Year event Inflow = 39.77 cfs @ 12.05 hrs, Volume= 2.430 af Outflow = 13.45 cfs @ 12.26 hrs, Volume= 2.430 af, Atten= 66%, Lag= 12.6 min Primary = 13.45 cfs @ 12.26 hrs, Volume= 2.430 af Routing by Stor-Ind method, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Starting Elev= 364.67' Surf.Area= 17,280 sf Storage= 8,346 cf Peak Elev= 368.41' @ 12.26 hrs Surf.Area= 33,653 sf Storage= 54,118 cf (45,772 cf above start) Plug-Flow detention time= 614.0 min calculated for 2.238 af (92% of inflow) Center-of-Mass det. time= 517.4 min ( 1,343.0 - 825.6 ) Volume Invert Avail.Storage Storage Description #1 362.00' 8,052 cf Custom Stage Data (Prismatic) Listed below (Recalc) 20,131 cf Overall x 40.0% Voids #2 364.33' 579 cf Custom Stage Data (Prismatic) Listed below (Recalc) 5,789 cf Overall x 10.0% Voids #3 365.00' 64,384 cf Custom Stage Data (Prismatic) Listed below (Recalc) 73,015 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 362.00 8,640 0 0 364.33 8,640 20,131 20,131 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 364.33 8,640 0 0 365.00 8,640 5,789 5,789 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 365.00 8,640 0 0 366.00 12,649 10,645 10,645 367.00 14,154 13,402 24,046 368.00 15,717 14,936 38,982 369.00 17,336 16,527 55,508 369.50 18,166 8,876 64,384 Device Routing Invert Outlet Devices #1 Primary 364.67'18.0" Round Culvert L= 37.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 364.67' / 358.00' S= 0.1803 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf #2 Device 1 364.67'2.8" Vert. Orifice/Grate C= 0.600 #3 Device 1 365.83'1.0" Vert. Orifice/Grate C= 0.600 #4 Device 1 367.50'48.0" W x 6.0" H Vert. Orifice/Grate C= 0.600 #5 Primary 368.00'8.0' long x 4.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 18HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef. (English) 2.38 2.54 2.69 2.68 2.67 2.67 2.65 2.66 2.66 2.68 2.72 2.73 2.76 2.79 2.88 3.07 3.32 Primary OutFlow Max=13.43 cfs @ 12.26 hrs HW=368.41' (Free Discharge) 1=Culvert (Passes 8.18 cfs of 11.61 cfs potential flow) 2=Orifice/Grate (Orifice Controls 0.39 cfs @ 9.16 fps) 3=Orifice/Grate (Orifice Controls 0.04 cfs @ 7.66 fps) 4=Orifice/Grate (Orifice Controls 7.75 cfs @ 3.87 fps) 5=Broad-Crested Rectangular Weir (Weir Controls 5.25 cfs @ 1.62 fps) Pond 253P: GravelWet5 InflowPrimary Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)44 42 40 38 36 34 32 30 28 26 24 22 20 18 16 14 12 10 8 6 4 2 0 Inflow Area=15.520 ac Peak Elev=368.41' Storage=54,118 cf 39.77 cfs 13.45 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 19HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 262P: GravelWet4 Inflow Area = 7.080 ac, Inflow Depth = 2.13" for 10 Year event Inflow = 24.15 cfs @ 12.00 hrs, Volume= 1.255 af Outflow = 7.11 cfs @ 12.15 hrs, Volume= 1.255 af, Atten= 71%, Lag= 9.3 min Primary = 7.11 cfs @ 12.15 hrs, Volume= 1.255 af Routing by Stor-Ind method, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Starting Elev= 379.67' Surf.Area= 10,880 sf Storage= 5,255 cf Peak Elev= 382.86' @ 12.15 hrs Surf.Area= 21,761 sf Storage= 29,702 cf (24,447 cf above start) Plug-Flow detention time= 538.8 min calculated for 1.134 af (90% of inflow) Center-of-Mass det. time= 430.0 min ( 1,239.6 - 809.5 ) Volume Invert Avail.Storage Storage Description #1 377.00' 5,070 cf Custom Stage Data (Prismatic) Listed below (Recalc) 12,675 cf Overall x 40.0% Voids #2 379.33' 364 cf Custom Stage Data (Prismatic) Listed below (Recalc) 3,645 cf Overall x 10.0% Voids #3 380.00' 31,690 cf Custom Stage Data (Prismatic) Listed below (Recalc) 37,125 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 377.00 5,440 0 0 379.33 5,440 12,675 12,675 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 379.33 5,440 0 0 380.00 5,440 3,645 3,645 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 380.00 5,440 0 0 381.00 8,025 6,733 6,733 382.00 9,537 8,781 15,514 383.00 11,105 10,321 25,835 383.50 12,318 5,856 31,690 Device Routing Invert Outlet Devices #1 Primary 379.67'18.0" Round Culvert L= 15.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 379.67' / 378.00' S= 0.1113 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf #2 Device 1 379.67'2.5" Vert. Orifice/Grate C= 0.600 #3 Device 1 380.95'1.0" Vert. Orifice/Grate C= 0.600 #4 Device 1 382.10'48.0" W x 6.0" H Vert. Orifice/Grate C= 0.600 #5 Primary 383.00'8.0' long x 4.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 20HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Coef. (English) 2.38 2.54 2.69 2.68 2.67 2.67 2.65 2.66 2.66 2.68 2.72 2.73 2.76 2.79 2.88 3.07 3.32 Primary OutFlow Max=7.11 cfs @ 12.15 hrs HW=382.86' (Free Discharge) 1=Culvert (Passes 7.11 cfs of 10.49 cfs potential flow) 2=Orifice/Grate (Orifice Controls 0.29 cfs @ 8.45 fps) 3=Orifice/Grate (Orifice Controls 0.04 cfs @ 6.58 fps) 4=Orifice/Grate (Orifice Controls 6.79 cfs @ 3.39 fps) 5=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Pond 262P: GravelWet4 InflowPrimary Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)26 24 22 20 18 16 14 12 10 8 6 4 2 0 Inflow Area=7.080 ac Peak Elev=382.86' Storage=29,702 cf 24.15 cfs 7.11 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 21HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 264P: GravelWet8 Inflow Area = 12.700 ac, Inflow Depth = 1.58" for 10 Year event Inflow = 28.07 cfs @ 12.05 hrs, Volume= 1.670 af Outflow = 5.00 cfs @ 12.42 hrs, Volume= 1.670 af, Atten= 82%, Lag= 22.2 min Primary = 5.00 cfs @ 12.42 hrs, Volume= 1.670 af Routing by Stor-Ind method, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Starting Elev= 330.67' Surf.Area= 18,000 sf Storage= 8,694 cf Peak Elev= 333.44' @ 12.42 hrs Surf.Area= 34,306 sf Storage= 41,964 cf (33,270 cf above start) Plug-Flow detention time= 596.5 min calculated for 1.471 af (88% of inflow) Center-of-Mass det. time= 460.8 min ( 1,299.3 - 838.5 ) Volume Invert Avail.Storage Storage Description #1 328.00' 8,388 cf Custom Stage Data (Prismatic) Listed below (Recalc) 20,970 cf Overall x 40.0% Voids #2 330.33' 603 cf Custom Stage Data (Prismatic) Listed below (Recalc) 6,030 cf Overall x 10.0% Voids #3 331.00' 51,235 cf Custom Stage Data (Prismatic) Listed below (Recalc) 60,226 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 328.00 9,000 0 0 330.33 9,000 20,970 20,970 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 330.33 9,000 0 0 331.00 9,000 6,030 6,030 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 331.00 9,000 0 0 332.00 13,677 11,339 11,339 333.00 15,480 14,579 25,917 334.00 17,340 16,410 42,327 334.50 18,291 8,908 51,235 Device Routing Invert Outlet Devices #1 Primary 330.67'18.0" Round Culvert L= 40.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 330.67' / 330.35' S= 0.0080 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf #2 Device 1 330.67'2.7" Vert. Orifice/Grate C= 0.600 #3 Device 1 331.20'1.0" Vert. Orifice/Grate C= 0.600 #4 Device 1 332.40'6.0" Vert. Orifice/Grate C= 0.600 #5 Device 1 333.00'48.0" W x 6.0" H Vert. Orifice/Grate C= 0.600 #6 Primary 333.50'8.0' long x 4.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 22HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef. (English) 2.38 2.54 2.69 2.68 2.67 2.67 2.65 2.66 2.66 2.68 2.72 2.73 2.76 2.79 2.88 3.07 3.32 Primary OutFlow Max=4.99 cfs @ 12.42 hrs HW=333.44' (Free Discharge) 1=Culvert (Passes 4.99 cfs of 9.56 cfs potential flow) 2=Orifice/Grate (Orifice Controls 0.31 cfs @ 7.86 fps) 3=Orifice/Grate (Orifice Controls 0.04 cfs @ 7.15 fps) 4=Orifice/Grate (Orifice Controls 0.84 cfs @ 4.29 fps) 5=Orifice/Grate (Orifice Controls 3.80 cfs @ 2.14 fps) 6=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Pond 264P: GravelWet8 InflowPrimary Hydrograph Time (hours)12512011511010510095908580757065605550454035302520151050Flow (cfs)30 28 26 24 22 20 18 16 14 12 10 8 6 4 2 0 Inflow Area=12.700 ac Peak Elev=333.44' Storage=41,964 cf 28.07 cfs 5.00 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 23HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 269P: GravelWet6A Inflow Area = 3.880 ac, Inflow Depth = 2.31" for 10 Year event Inflow = 14.86 cfs @ 11.98 hrs, Volume= 0.745 af Outflow = 5.85 cfs @ 12.09 hrs, Volume= 0.745 af, Atten= 61%, Lag= 6.7 min Primary = 5.85 cfs @ 12.09 hrs, Volume= 0.745 af Routing by Stor-Ind method, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Starting Elev= 375.67' Surf.Area= 7,300 sf Storage= 3,526 cf Peak Elev= 378.51' @ 12.09 hrs Surf.Area= 14,420 sf Storage= 17,889 cf (14,363 cf above start) Plug-Flow detention time= 545.2 min calculated for 0.664 af (89% of inflow) Center-of-Mass det. time= 423.3 min ( 1,222.8 - 799.5 ) Volume Invert Avail.Storage Storage Description #1 373.00' 3,402 cf Custom Stage Data (Prismatic) Listed below (Recalc) 8,504 cf Overall x 40.0% Voids #2 375.33' 245 cf Custom Stage Data (Prismatic) Listed below (Recalc) 2,446 cf Overall x 10.0% Voids #3 376.00' 21,800 cf Custom Stage Data (Prismatic) Listed below (Recalc) 25,446 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 373.00 3,650 0 0 375.33 3,650 8,504 8,504 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 375.33 3,650 0 0 376.00 3,650 2,446 2,446 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 376.00 3,650 0 0 377.00 5,622 4,636 4,636 378.00 6,595 6,109 10,745 379.00 7,624 7,110 17,854 379.50 8,160 3,946 21,800 Device Routing Invert Outlet Devices #1 Primary 375.67'18.0" Round Culvert L= 90.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 375.67' / 370.00' S= 0.0630 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf #2 Device 1 375.67'2.0" Vert. Orifice/Grate C= 0.600 #3 Device 1 376.90'1.0" Vert. Orifice/Grate C= 0.600 #4 Device 1 377.90'48.0" W x 6.0" H Vert. Orifice/Grate C= 0.600 Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 24HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Primary OutFlow Max=5.86 cfs @ 12.09 hrs HW=378.51' (Free Discharge) 1=Culvert (Passes 5.86 cfs of 9.71 cfs potential flow) 2=Orifice/Grate (Orifice Controls 0.17 cfs @ 7.99 fps) 3=Orifice/Grate (Orifice Controls 0.03 cfs @ 6.03 fps) 4=Orifice/Grate (Orifice Controls 5.65 cfs @ 2.82 fps) Pond 269P: GravelWet6A Inflow Primary Hydrograph Time (hours)12512011511010510095908580757065605550454035302520151050Flow (cfs)16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Inflow Area=3.880 ac Peak Elev=378.51' Storage=17,889 cf 14.86 cfs 5.85 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 25HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 275P: GravelWet6B Inflow Area = 5.320 ac, Inflow Depth = 2.13" for 10 Year event Inflow = 17.65 cfs @ 12.00 hrs, Volume= 0.943 af Outflow = 5.91 cfs @ 12.16 hrs, Volume= 0.943 af, Atten= 67%, Lag= 9.1 min Primary = 5.91 cfs @ 12.16 hrs, Volume= 0.943 af Routing by Stor-Ind method, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Starting Elev= 332.17' Surf.Area= 10,260 sf Storage= 4,956 cf Peak Elev= 334.81' @ 12.16 hrs Surf.Area= 19,935 sf Storage= 23,039 cf (18,083 cf above start) Plug-Flow detention time= 571.1 min calculated for 0.829 af (88% of inflow) Center-of-Mass det. time= 436.5 min ( 1,246.7 - 810.3 ) Volume Invert Avail.Storage Storage Description #1 329.50' 4,781 cf Custom Stage Data (Prismatic) Listed below (Recalc) 11,953 cf Overall x 40.0% Voids #2 331.83' 344 cf Custom Stage Data (Prismatic) Listed below (Recalc) 3,437 cf Overall x 10.0% Voids #3 332.50' 30,552 cf Custom Stage Data (Prismatic) Listed below (Recalc) 35,677 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 329.50 5,130 0 0 331.83 5,130 11,953 11,953 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 331.83 5,130 0 0 332.50 5,130 3,437 3,437 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 332.50 5,130 0 0 333.00 6,813 2,986 2,986 334.00 8,365 7,589 10,575 335.00 9,975 9,170 19,745 336.00 11,640 10,808 30,552 Device Routing Invert Outlet Devices #1 Primary 332.17'24.0" Round Culvert L= 284.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 332.17' / 330.75' S= 0.0050 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 3.14 sf #2 Device 1 332.17'2.2" Vert. Orifice/Grate C= 0.600 #3 Device 1 333.25'1.0" Vert. Orifice/Grate C= 0.600 #4 Device 1 334.20'48.0" W x 6.0" H Vert. Orifice/Grate C= 0.600 Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 26HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Primary OutFlow Max=5.91 cfs @ 12.16 hrs HW=334.81' (Free Discharge) 1=Culvert (Passes 5.91 cfs of 15.31 cfs potential flow) 2=Orifice/Grate (Orifice Controls 0.20 cfs @ 7.69 fps) 3=Orifice/Grate (Orifice Controls 0.03 cfs @ 5.94 fps) 4=Orifice/Grate (Orifice Controls 5.68 cfs @ 2.84 fps) Pond 275P: GravelWet6B Inflow Primary Hydrograph Time (hours)12512011511010510095908580757065605550454035302520151050Flow (cfs)19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Inflow Area=5.320 ac Peak Elev=334.81' Storage=23,039 cf 17.65 cfs 5.91 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 27HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Link 250L: SN004 Inflow Area = 6.550 ac, Inflow Depth = 2.31" for 10 Year event Inflow = 7.04 cfs @ 12.22 hrs, Volume= 1.258 af Primary = 7.04 cfs @ 12.22 hrs, Volume= 1.258 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Link 250L: SN004 Inflow Primary Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)7 6 5 4 3 2 1 0 Inflow Area=6.550 ac 7.04 cfs7.04 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 28HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Link 251L: SN006 Inflow Area = 7.080 ac, Inflow Depth = 2.13" for 10 Year event Inflow = 7.11 cfs @ 12.15 hrs, Volume= 1.255 af Primary = 7.11 cfs @ 12.15 hrs, Volume= 1.255 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Link 251L: SN006 Inflow Primary Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)7 6 5 4 3 2 1 0 Inflow Area=7.080 ac 7.11 cfs7.11 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 29HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Link 252L: SN007 Inflow Area = 15.520 ac, Inflow Depth = 1.88" for 10 Year event Inflow = 13.45 cfs @ 12.26 hrs, Volume= 2.430 af Primary = 13.45 cfs @ 12.26 hrs, Volume= 2.430 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Link 252L: SN007 Inflow Primary Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Inflow Area=15.520 ac 13.45 cfs13.45 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 30HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Link 253L: SN008 Inflow Area = 9.200 ac, Inflow Depth = 2.20" for 10 Year event Inflow = 11.50 cfs @ 12.12 hrs, Volume= 1.688 af Primary = 11.50 cfs @ 12.12 hrs, Volume= 1.688 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Link 253L: SN008 Inflow Primary Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)12 11 10 9 8 7 6 5 4 3 2 1 0 Inflow Area=9.200 ac 11.50 cfs11.50 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 31HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Link 254L: SN009 Inflow Area = 4.090 ac, Inflow Depth = 1.80" for 10 Year event Inflow = 0.73 cfs @ 12.97 hrs, Volume= 0.614 af Primary = 0.73 cfs @ 12.97 hrs, Volume= 0.614 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Link 254L: SN009 Inflow Primary Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)0.8 0.75 0.7 0.65 0.6 0.55 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Inflow Area=4.090 ac 0.73 cfs0.73 cfs Type II 24-hr 10 Year Rainfall=3.25"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 32HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Link 255L: SN010 Inflow Area = 12.700 ac, Inflow Depth = 1.58" for 10 Year event Inflow = 5.00 cfs @ 12.42 hrs, Volume= 1.670 af Primary = 5.00 cfs @ 12.42 hrs, Volume= 1.670 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Link 255L: SN010 Inflow Primary Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)5 4 3 2 1 0 Inflow Area=12.700 ac 5.00 cfs5.00 cfs 2022 Application 17S GW3-Pre 18S GW4-Pre 19S GW5-Pre 20S GW6A-Pre 21S GW6B-Pre 22S GW7-Pre 23S GW8-Pre 18L SN4 19L SN6 20L SN7 21L SN8 22L SN9 23L SN10 Routing Diagram for Eastview2022-prePrepared by Krebs & Lansing Consulting Engineers, Inc., Printed 4/6/2022 HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Subcat Reach Pond Link Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 2HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Project Notes Eastview Pre Development Stormwater Model Qp10 & Qp100 Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 3HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Area Listing (selected nodes) Area (acres) CN Description (subcatchment-numbers) 29.150 78 Workbook (17S, 18S, 19S) 25.990 77 Workbook (20S, 21S, 22S, 23S) 55.140 78 TOTAL AREA Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 4HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Time span=5.00-48.00 hrs, dt=0.05 hrs, 861 points Runoff by SCS TR-20 method, UH=SCS, Weighted-Q Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=6.550 ac Runoff Depth=2.58"Subcatchment 17S: GW3-Pre Tc=18.9 min CN=78 Runoff=19.35 cfs 1.411 af Runoff Area=7.080 ac Runoff Depth=2.58"Subcatchment 18S: GW4-Pre Tc=12.0 min CN=78 Runoff=25.97 cfs 1.525 af Runoff Area=15.520 ac Runoff Depth=2.58"Subcatchment 19S: GW5-Pre Tc=17.3 min CN=78 Runoff=48.07 cfs 3.343 af Runoff Area=3.880 ac Runoff Depth=2.50"Subcatchment 20S: GW6A-Pre Tc=10.9 min CN=77 Runoff=14.24 cfs 0.808 af Runoff Area=5.320 ac Runoff Depth=2.50"Subcatchment 21S: GW6B-Pre Tc=13.6 min CN=77 Runoff=17.90 cfs 1.107 af Runoff Area=4.090 ac Runoff Depth=2.50"Subcatchment 22S: GW7-Pre Tc=8.7 min CN=77 Runoff=16.28 cfs 0.851 af Runoff Area=12.700 ac Runoff Depth=2.50"Subcatchment 23S: GW8-Pre Tc=14.8 min CN=77 Runoff=41.01 cfs 2.644 af Inflow=19.35 cfs 1.411 afLink 18L: SN4 Primary=19.35 cfs 1.411 af Inflow=25.97 cfs 1.525 afLink 19L: SN6 Primary=25.97 cfs 1.525 af Inflow=48.07 cfs 3.343 afLink 20L: SN7 Primary=48.07 cfs 3.343 af Inflow=31.87 cfs 1.915 afLink 21L: SN8 Primary=31.87 cfs 1.915 af Inflow=16.28 cfs 0.851 afLink 22L: SN9 Primary=16.28 cfs 0.851 af Inflow=41.01 cfs 2.644 afLink 23L: SN10 Primary=41.01 cfs 2.644 af Total Runoff Area = 55.140 ac Runoff Volume = 11.689 af Average Runoff Depth = 2.54" Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 5HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 17S: GW3-Pre Area to 24" Culvert on Kennedy Drive east of Windridge Runoff = 19.35 cfs @ 12.12 hrs, Volume= 1.411 af, Depth= 2.58" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 5.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 100 Year Rainfall=4.85" Area (ac) CN Description * 6.550 78 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 18.9 Direct Entry, Workbook-Lag Subcatchment 17S: GW3-Pre Runoff Hydrograph Time (hours)48474645444342414039383736353433323130292827262524232221201918171615141312111098765Flow (cfs)21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Type II 24-hr 100 Year Rainfall=4.85" Runoff Area=6.550 ac Runoff Volume=1.411 af Runoff Depth=2.58" Tc=18.9 min CN=78 19.35 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 6HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 18S: GW4-Pre Area to 24" Culvert on Kennedy Drive east of Windridge Runoff = 25.97 cfs @ 12.04 hrs, Volume= 1.525 af, Depth= 2.58" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 5.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 100 Year Rainfall=4.85" Area (ac) CN Description * 7.080 78 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 12.0 Direct Entry, Workbook-Lag Subcatchment 18S: GW4-Pre Runoff Hydrograph Time (hours)48474645444342414039383736353433323130292827262524232221201918171615141312111098765Flow (cfs)28 26 24 22 20 18 16 14 12 10 8 6 4 2 0 Type II 24-hr 100 Year Rainfall=4.85" Runoff Area=7.080 ac Runoff Volume=1.525 af Runoff Depth=2.58" Tc=12.0 min CN=78 25.97 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 7HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 19S: GW5-Pre Area to 24" Culvert on Kennedy Drive east of Windridge Runoff = 48.07 cfs @ 12.10 hrs, Volume= 3.343 af, Depth= 2.58" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 5.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 100 Year Rainfall=4.85" Area (ac) CN Description * 15.520 78 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 17.3 Direct Entry, Workbook-Lag Subcatchment 19S: GW5-Pre Runoff Hydrograph Time (hours)48474645444342414039383736353433323130292827262524232221201918171615141312111098765Flow (cfs)50 45 40 35 30 25 20 15 10 5 0 Type II 24-hr 100 Year Rainfall=4.85" Runoff Area=15.520 ac Runoff Volume=3.343 af Runoff Depth=2.58" Tc=17.3 min CN=78 48.07 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 8HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 20S: GW6A-Pre Area to 24" Culvert on Kennedy Drive east of Windridge Runoff = 14.24 cfs @ 12.03 hrs, Volume= 0.808 af, Depth= 2.50" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 5.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 100 Year Rainfall=4.85" Area (ac) CN Description * 3.880 77 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.9 Direct Entry, Workbook-Lag Subcatchment 20S: GW6A-Pre Runoff Hydrograph Time (hours)48474645444342414039383736353433323130292827262524232221201918171615141312111098765Flow (cfs)15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Type II 24-hr 100 Year Rainfall=4.85" Runoff Area=3.880 ac Runoff Volume=0.808 af Runoff Depth=2.50" Tc=10.9 min CN=77 14.24 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 9HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 21S: GW6B-Pre Area to 24" Culvert on Kennedy Drive east of Windridge Runoff = 17.90 cfs @ 12.06 hrs, Volume= 1.107 af, Depth= 2.50" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 5.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 100 Year Rainfall=4.85" Area (ac) CN Description * 5.320 77 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 13.6 Direct Entry, Workbook-Lag Subcatchment 21S: GW6B-Pre Runoff Hydrograph Time (hours)48474645444342414039383736353433323130292827262524232221201918171615141312111098765Flow (cfs)20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Type II 24-hr 100 Year Rainfall=4.85" Runoff Area=5.320 ac Runoff Volume=1.107 af Runoff Depth=2.50" Tc=13.6 min CN=77 17.90 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 10HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 22S: GW7-Pre Area to 24" Culvert on Kennedy Drive east of Windridge Runoff = 16.28 cfs @ 12.00 hrs, Volume= 0.851 af, Depth= 2.50" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 5.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 100 Year Rainfall=4.85" Area (ac) CN Description * 4.090 77 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 8.7 Direct Entry, Workbook-Lag Subcatchment 22S: GW7-Pre Runoff Hydrograph Time (hours)48474645444342414039383736353433323130292827262524232221201918171615141312111098765Flow (cfs)18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Type II 24-hr 100 Year Rainfall=4.85" Runoff Area=4.090 ac Runoff Volume=0.851 af Runoff Depth=2.50" Tc=8.7 min CN=77 16.28 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 11HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 23S: GW8-Pre Area to 24" Culvert on Kennedy Drive east of Windridge Runoff = 41.01 cfs @ 12.07 hrs, Volume= 2.644 af, Depth= 2.50" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 5.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 100 Year Rainfall=4.85" Area (ac) CN Description * 12.700 77 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 14.8 Direct Entry, Workbook-Lag Subcatchment 23S: GW8-Pre Runoff Hydrograph Time (hours)48474645444342414039383736353433323130292827262524232221201918171615141312111098765Flow (cfs)44 42 40 38 36 34 32 30 28 26 24 22 20 18 16 14 12 10 8 6 4 2 0 Type II 24-hr 100 Year Rainfall=4.85" Runoff Area=12.700 ac Runoff Volume=2.644 af Runoff Depth=2.50" Tc=14.8 min CN=77 41.01 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 12HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Link 18L: SN4 Inflow Area = 6.550 ac, Inflow Depth = 2.58" for 100 Year event Inflow = 19.35 cfs @ 12.12 hrs, Volume= 1.411 af Primary = 19.35 cfs @ 12.12 hrs, Volume= 1.411 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-48.00 hrs, dt= 0.05 hrs Link 18L: SN4 Inflow Primary Hydrograph Time (hours) 484644424038363432302826242220181614121086Flow (cfs)21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Inflow Area=6.550 ac 19.35 cfs19.35 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 13HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Link 19L: SN6 Inflow Area = 7.080 ac, Inflow Depth = 2.58" for 100 Year event Inflow = 25.97 cfs @ 12.04 hrs, Volume= 1.525 af Primary = 25.97 cfs @ 12.04 hrs, Volume= 1.525 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-48.00 hrs, dt= 0.05 hrs Link 19L: SN6 Inflow Primary Hydrograph Time (hours) 484644424038363432302826242220181614121086Flow (cfs)28 26 24 22 20 18 16 14 12 10 8 6 4 2 0 Inflow Area=7.080 ac 25.97 cfs25.97 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 14HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Link 20L: SN7 Inflow Area = 15.520 ac, Inflow Depth = 2.58" for 100 Year event Inflow = 48.07 cfs @ 12.10 hrs, Volume= 3.343 af Primary = 48.07 cfs @ 12.10 hrs, Volume= 3.343 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-48.00 hrs, dt= 0.05 hrs Link 20L: SN7 Inflow Primary Hydrograph Time (hours) 484644424038363432302826242220181614121086Flow (cfs)50 45 40 35 30 25 20 15 10 5 0 Inflow Area=15.520 ac 48.07 cfs48.07 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 15HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Link 21L: SN8 Inflow Area = 9.200 ac, Inflow Depth = 2.50" for 100 Year event Inflow = 31.87 cfs @ 12.04 hrs, Volume= 1.915 af Primary = 31.87 cfs @ 12.04 hrs, Volume= 1.915 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-48.00 hrs, dt= 0.05 hrs Link 21L: SN8 Inflow Primary Hydrograph Time (hours) 484644424038363432302826242220181614121086Flow (cfs)34 32 30 28 26 24 22 20 18 16 14 12 10 8 6 4 2 0 Inflow Area=9.200 ac 31.87 cfs31.87 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 16HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Link 22L: SN9 Inflow Area = 4.090 ac, Inflow Depth = 2.50" for 100 Year event Inflow = 16.28 cfs @ 12.00 hrs, Volume= 0.851 af Primary = 16.28 cfs @ 12.00 hrs, Volume= 0.851 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-48.00 hrs, dt= 0.05 hrs Link 22L: SN9 Inflow Primary Hydrograph Time (hours) 484644424038363432302826242220181614121086Flow (cfs)18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Inflow Area=4.090 ac 16.28 cfs16.28 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-pre Printed 4/6/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 17HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Link 23L: SN10 Inflow Area = 12.700 ac, Inflow Depth = 2.50" for 100 Year event Inflow = 41.01 cfs @ 12.07 hrs, Volume= 2.644 af Primary = 41.01 cfs @ 12.07 hrs, Volume= 2.644 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-48.00 hrs, dt= 0.05 hrs Link 23L: SN10 Inflow Primary Hydrograph Time (hours) 484644424038363432302826242220181614121086Flow (cfs)44 42 40 38 36 34 32 30 28 26 24 22 20 18 16 14 12 10 8 6 4 2 0 Inflow Area=12.700 ac 41.01 cfs41.01 cfs Qp100 242S GW3 250S GW7 251S GW5 259S GW8 263S GW4 270S GW6A 276S GW6B 243P GravelWet3 251P GravelWet7 252P GravelWet5 263P GravelWet8 265P GravelWet4 271P GravelWet6A 277P GravelWet6B 245L Sn004 246L Sn006 247L Sn007 248L Sn009 249L Sn010 278L Sn008 Routing Diagram for Eastview2022-postPrepared by Krebs & Lansing Consulting Engineers, Inc., Printed 4/7/2022 HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Subcat Reach Pond Link Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 2HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Project Notes EASTVIEW Old Farm Road & Kimball Avenue South Burlington, Vermont Post Development Stormwater Model Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 3HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Area Listing (selected nodes) Area (acres) CN Description (subcatchment-numbers) 6.550 91 Workbook (242S) 19.610 85 Workbook (250S, 251S) 12.700 82 Workbook (259S) 7.080 88 Workbook (263S) 3.880 90 Workbook (270S) 5.320 89 Workbook (276S) 55.140 86 TOTAL AREA Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 4HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Time span=0.00-128.00 hrs, dt=0.01 hrs, 12801 points Runoff by SCS TR-20 method, UH=SCS, Weighted-Q Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=6.550 ac Runoff Depth=3.84"Subcatchment 242S: GW3 Tc=12.0 min CN=91 Runoff=34.12 cfs 2.094 af Runoff Area=4.090 ac Runoff Depth=3.23"Subcatchment 250S: GW7 Tc=6.8 min CN=85 Runoff=22.24 cfs 1.101 af Runoff Area=15.520 ac Runoff Depth=3.23"Subcatchment 251S: GW5 Tc=13.7 min CN=85 Runoff=66.81 cfs 4.177 af Runoff Area=12.700 ac Runoff Depth=2.95"Subcatchment 259S: GW8 Tc=12.8 min CN=82 Runoff=51.90 cfs 3.117 af Runoff Area=7.080 ac Runoff Depth=3.53"Subcatchment 263S: GW4 Tc=8.5 min CN=88 Runoff=38.95 cfs 2.081 af Runoff Area=3.880 ac Runoff Depth=3.73"Subcatchment 270S: GW6A Tc=7.0 min CN=90 Runoff=23.37 cfs 1.207 af Runoff Area=5.320 ac Runoff Depth=3.63"Subcatchment 276S: GW6B Tc=9.3 min CN=89 Runoff=29.10 cfs 1.609 af Peak Elev=376.47' Storage=41,610 cf Inflow=34.12 cfs 2.094 afPond 243P: GravelWet3 Outflow=19.20 cfs 2.094 af Peak Elev=329.81' Storage=36,676 cf Inflow=22.24 cfs 1.101 afPond 251P: GravelWet7 Outflow=1.24 cfs 1.101 af Peak Elev=369.33' Storage=69,952 cf Inflow=66.81 cfs 4.177 afPond 252P: GravelWet5 Outflow=45.19 cfs 4.177 af Peak Elev=334.37' Storage=57,900 cf Inflow=51.90 cfs 3.117 afPond 263P: GravelWet8 Outflow=28.98 cfs 3.117 af Peak Elev=383.70' Storage=39,389 cf Inflow=38.95 cfs 2.081 afPond 265P: GravelWet4 Outflow=24.00 cfs 2.081 af Peak Elev=379.35' Storage=24,263 cf Inflow=23.37 cfs 1.207 afPond 271P: GravelWet6A Outflow=10.79 cfs 1.207 af Peak Elev=335.80' Storage=33,358 cf Inflow=29.10 cfs 1.609 afPond 277P: GravelWet6B Outflow=11.44 cfs 1.609 af Inflow=19.20 cfs 2.094 afLink 245L: Sn004 Primary=19.20 cfs 2.094 af Inflow=24.00 cfs 2.081 afLink 246L: Sn006 Primary=24.00 cfs 2.081 af Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 5HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Inflow=45.19 cfs 4.177 afLink 247L: Sn007 Primary=45.19 cfs 4.177 af Inflow=1.24 cfs 1.101 afLink 248L: Sn009 Primary=1.24 cfs 1.101 af Inflow=28.98 cfs 3.117 afLink 249L: Sn010 Primary=28.98 cfs 3.117 af Inflow=22.05 cfs 2.815 afLink 278L: Sn008 Primary=22.05 cfs 2.815 af Total Runoff Area = 55.140 ac Runoff Volume = 15.385 af Average Runoff Depth = 3.35" Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 6HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 242S: GW3 Runoff = 34.12 cfs @ 12.03 hrs, Volume= 2.094 af, Depth= 3.84" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Type II 24-hr 100 Year Rainfall=4.85" Area (ac) CN Description * 6.550 91 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 12.0 Direct Entry, Workbook- Lag Subcatchment 242S: GW3 Runoff Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)38 36 34 32 30 28 26 24 22 20 18 16 14 12 10 8 6 4 2 0 Type II 24-hr 100 Year Rainfall=4.85" Runoff Area=6.550 ac Runoff Volume=2.094 af Runoff Depth=3.84" Tc=12.0 min CN=91 34.12 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 7HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 250S: GW7 Runoff = 22.24 cfs @ 11.98 hrs, Volume= 1.101 af, Depth= 3.23" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Type II 24-hr 100 Year Rainfall=4.85" Area (ac) CN Description * 4.090 85 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.8 Direct Entry, Workbook- Lag Subcatchment 250S: GW7 Runoff Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Type II 24-hr 100 Year Rainfall=4.85" Runoff Area=4.090 ac Runoff Volume=1.101 af Runoff Depth=3.23" Tc=6.8 min CN=85 22.24 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 8HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 251S: GW5 Runoff = 66.81 cfs @ 12.05 hrs, Volume= 4.177 af, Depth= 3.23" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Type II 24-hr 100 Year Rainfall=4.85" Area (ac) CN Description * 15.520 85 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 13.7 Direct Entry, Workbook- Lag Subcatchment 251S: GW5 Runoff Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)70 65 60 55 50 45 40 35 30 25 20 15 10 5 0 Type II 24-hr 100 Year Rainfall=4.85" Runoff Area=15.520 ac Runoff Volume=4.177 af Runoff Depth=3.23" Tc=13.7 min CN=85 66.81 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 9HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 259S: GW8 Runoff = 51.90 cfs @ 12.05 hrs, Volume= 3.117 af, Depth= 2.95" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Type II 24-hr 100 Year Rainfall=4.85" Area (ac) CN Description * 12.700 82 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 12.8 Direct Entry, Workbook- Lag Subcatchment 259S: GW8 Runoff Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)55 50 45 40 35 30 25 20 15 10 5 0 Type II 24-hr 100 Year Rainfall=4.85" Runoff Area=12.700 ac Runoff Volume=3.117 af Runoff Depth=2.95" Tc=12.8 min CN=82 51.90 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 10HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 263S: GW4 Runoff = 38.95 cfs @ 12.00 hrs, Volume= 2.081 af, Depth= 3.53" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Type II 24-hr 100 Year Rainfall=4.85" Area (ac) CN Description * 7.080 88 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 8.5 Direct Entry, Workbook- Lag Subcatchment 263S: GW4 Runoff Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)42 40 38 36 34 32 30 28 26 24 22 20 18 16 14 12 10 8 6 4 2 0 Type II 24-hr 100 Year Rainfall=4.85" Runoff Area=7.080 ac Runoff Volume=2.081 af Runoff Depth=3.53" Tc=8.5 min CN=88 38.95 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 11HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 270S: GW6A Runoff = 23.37 cfs @ 11.98 hrs, Volume= 1.207 af, Depth= 3.73" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Type II 24-hr 100 Year Rainfall=4.85" Area (ac) CN Description * 3.880 90 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 7.0 Direct Entry, Workbook- Lag Subcatchment 270S: GW6A Runoff Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Type II 24-hr 100 Year Rainfall=4.85" Runoff Area=3.880 ac Runoff Volume=1.207 af Runoff Depth=3.73" Tc=7.0 min CN=90 23.37 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 12HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 276S: GW6B Runoff = 29.10 cfs @ 12.00 hrs, Volume= 1.609 af, Depth= 3.63" Runoff by SCS TR-20 method, UH=SCS, Weighted-Q, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Type II 24-hr 100 Year Rainfall=4.85" Area (ac) CN Description * 5.320 89 Workbook Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 9.3 Direct Entry, Workbook- Lag Subcatchment 276S: GW6B Runoff Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)32 30 28 26 24 22 20 18 16 14 12 10 8 6 4 2 0 Type II 24-hr 100 Year Rainfall=4.85" Runoff Area=5.320 ac Runoff Volume=1.609 af Runoff Depth=3.63" Tc=9.3 min CN=89 29.10 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 13HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 243P: GravelWet3 Inflow Area = 6.550 ac, Inflow Depth = 3.84" for 100 Year event Inflow = 34.12 cfs @ 12.03 hrs, Volume= 2.094 af Outflow = 19.20 cfs @ 12.15 hrs, Volume= 2.094 af, Atten= 44%, Lag= 7.1 min Primary = 19.20 cfs @ 12.15 hrs, Volume= 2.094 af Routing by Stor-Ind method, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Starting Elev= 372.67' Surf.Area= 14,880 sf Storage= 7,187 cf Peak Elev= 376.47' @ 12.15 hrs Surf.Area= 26,979 sf Storage= 41,610 cf (34,423 cf above start) Plug-Flow detention time= 368.7 min calculated for 1.929 af (92% of inflow) Center-of-Mass det. time= 287.8 min ( 1,077.9 - 790.1 ) Volume Invert Avail.Storage Storage Description #1 370.00' 6,934 cf Custom Stage Data (Prismatic) Listed below (Recalc) 17,335 cf Overall x 40.0% Voids #2 372.33' 498 cf Custom Stage Data (Prismatic) Listed below (Recalc) 4,985 cf Overall x 10.0% Voids #3 373.00' 34,521 cf Custom Stage Data (Prismatic) Listed below (Recalc) 41,953 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 370.00 7,440 0 0 372.33 7,440 17,335 17,335 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 372.33 7,440 0 0 373.00 7,440 4,985 4,985 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 373.00 7,440 0 0 374.00 8,968 8,204 8,204 375.00 10,193 9,581 17,785 376.00 11,474 10,834 28,618 376.50 12,136 5,903 34,521 Device Routing Invert Outlet Devices #1 Primary 372.67'24.0" Round Culvert L= 15.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 372.67' / 371.00' S= 0.1113 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 3.14 sf #2 Device 1 372.67'2.8" Vert. Orifice/Grate C= 0.600 #3 Device 1 373.90'1.0" Vert. Orifice/Grate C= 0.600 #4 Device 1 375.00'48.0" W x 12.0" H Vert. Orifice/Grate C= 0.600 Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 14HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Primary OutFlow Max=19.20 cfs @ 12.15 hrs HW=376.47' (Free Discharge) 1=Culvert (Passes 19.20 cfs of 19.99 cfs potential flow) 2=Orifice/Grate (Orifice Controls 0.40 cfs @ 9.24 fps) 3=Orifice/Grate (Orifice Controls 0.04 cfs @ 7.66 fps) 4=Orifice/Grate (Orifice Controls 18.76 cfs @ 4.69 fps) Pond 243P: GravelWet3 Inflow Primary Hydrograph Time (hours)12512011511010510095908580757065605550454035302520151050Flow (cfs)38 36 34 32 30 28 26 24 22 20 18 16 14 12 10 8 6 4 2 0 Inflow Area=6.550 ac Peak Elev=376.47' Storage=41,610 cf 34.12 cfs 19.20 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 15HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 251P: GravelWet7 Inflow Area = 4.090 ac, Inflow Depth = 3.23" for 100 Year event Inflow = 22.24 cfs @ 11.98 hrs, Volume= 1.101 af Outflow = 1.24 cfs @ 12.92 hrs, Volume= 1.101 af, Atten= 94%, Lag= 56.6 min Primary = 1.24 cfs @ 12.92 hrs, Volume= 1.101 af Routing by Stor-Ind method, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Starting Elev= 327.67' Surf.Area= 20,916 sf Storage= 10,102 cf Peak Elev= 329.81' @ 12.92 hrs Surf.Area= 37,976 sf Storage= 36,676 cf (26,573 cf above start) Plug-Flow detention time= 566.2 min calculated for 0.869 af (79% of inflow) Center-of-Mass det. time= 368.6 min ( 1,175.0 - 806.4 ) Volume Invert Avail.Storage Storage Description #1 325.00' 9,747 cf Custom Stage Data (Prismatic) Listed below (Recalc) 24,367 cf Overall x 40.0% Voids #2 327.33' 701 cf Custom Stage Data (Prismatic) Listed below (Recalc) 7,007 cf Overall x 10.0% Voids #3 328.00' 68,080 cf Custom Stage Data (Prismatic) Listed below (Recalc) 78,528 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 325.00 10,458 0 0 327.33 10,458 24,367 24,367 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 327.33 10,458 0 0 328.00 10,458 7,007 7,007 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 328.00 10,458 0 0 329.00 15,610 13,034 13,034 330.00 17,405 16,508 29,542 331.00 19,255 18,330 47,872 332.00 21,162 20,209 68,080 Device Routing Invert Outlet Devices #1 Primary 327.67'18.0" Round Culvert L= 57.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 327.67' / 327.10' S= 0.0100 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf #2 Device 1 327.67'2.5" Vert. Orifice/Grate C= 0.600 #3 Device 1 328.10'1.0" Vert. Orifice/Grate C= 0.600 #4 Device 1 328.50'6.0" Vert. Orifice/Grate C= 0.600 #5 Device 1 330.50'48.0" W x 6.0" H Vert. Orifice/Grate C= 0.600 #6 Primary 331.00'8.0' long x 4.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 16HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef. (English) 2.38 2.54 2.69 2.68 2.67 2.67 2.65 2.66 2.66 2.68 2.72 2.73 2.76 2.79 2.88 3.07 3.32 Primary OutFlow Max=1.24 cfs @ 12.92 hrs HW=329.81' (Free Discharge) 1=Culvert (Passes 1.24 cfs of 7.91 cfs potential flow) 2=Orifice/Grate (Orifice Controls 0.23 cfs @ 6.87 fps) 3=Orifice/Grate (Orifice Controls 0.03 cfs @ 6.21 fps) 4=Orifice/Grate (Orifice Controls 0.97 cfs @ 4.95 fps) 5=Orifice/Grate ( Controls 0.00 cfs) 6=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Pond 251P: GravelWet7 InflowPrimary Hydrograph Time (hours)12512011511010510095908580757065605550454035302520151050Flow (cfs)24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Inflow Area=4.090 ac Peak Elev=329.81' Storage=36,676 cf 22.24 cfs 1.24 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 17HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 252P: GravelWet5 Inflow Area = 15.520 ac, Inflow Depth = 3.23" for 100 Year event Inflow = 66.81 cfs @ 12.05 hrs, Volume= 4.177 af Outflow = 45.19 cfs @ 12.16 hrs, Volume= 4.177 af, Atten= 32%, Lag= 6.3 min Primary = 45.19 cfs @ 12.16 hrs, Volume= 4.177 af Routing by Stor-Ind method, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Starting Elev= 364.67' Surf.Area= 17,280 sf Storage= 8,346 cf Peak Elev= 369.33' @ 12.16 hrs Surf.Area= 35,164 sf Storage= 69,952 cf (61,606 cf above start) Plug-Flow detention time= 366.7 min calculated for 3.985 af (95% of inflow) Center-of-Mass det. time= 318.0 min ( 1,130.8 - 812.8 ) Volume Invert Avail.Storage Storage Description #1 362.00' 8,052 cf Custom Stage Data (Prismatic) Listed below (Recalc) 20,131 cf Overall x 40.0% Voids #2 364.33' 579 cf Custom Stage Data (Prismatic) Listed below (Recalc) 5,789 cf Overall x 10.0% Voids #3 365.00' 64,384 cf Custom Stage Data (Prismatic) Listed below (Recalc) 73,015 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 362.00 8,640 0 0 364.33 8,640 20,131 20,131 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 364.33 8,640 0 0 365.00 8,640 5,789 5,789 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 365.00 8,640 0 0 366.00 12,649 10,645 10,645 367.00 14,154 13,402 24,046 368.00 15,717 14,936 38,982 369.00 17,336 16,527 55,508 369.50 18,166 8,876 64,384 Device Routing Invert Outlet Devices #1 Primary 364.67'18.0" Round Culvert L= 37.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 364.67' / 358.00' S= 0.1803 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf #2 Device 1 364.67'2.8" Vert. Orifice/Grate C= 0.600 #3 Device 1 365.85'1.0" Vert. Orifice/Grate C= 0.600 #4 Device 1 367.50'48.0" W x 6.0" H Vert. Orifice/Grate C= 0.600 #5 Primary 368.00'8.0' long x 4.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 18HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef. (English) 2.38 2.54 2.69 2.68 2.67 2.67 2.65 2.66 2.66 2.68 2.72 2.73 2.76 2.79 2.88 3.07 3.32 Primary OutFlow Max=45.17 cfs @ 12.16 hrs HW=369.33' (Free Discharge) 1=Culvert (Passes 12.58 cfs of 13.28 cfs potential flow) 2=Orifice/Grate (Orifice Controls 0.44 cfs @ 10.26 fps) 3=Orifice/Grate (Orifice Controls 0.05 cfs @ 8.93 fps) 4=Orifice/Grate (Orifice Controls 12.09 cfs @ 6.05 fps) 5=Broad-Crested Rectangular Weir (Weir Controls 32.59 cfs @ 3.06 fps) Pond 252P: GravelWet5 InflowPrimary Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)70 65 60 55 50 45 40 35 30 25 20 15 10 5 0 Inflow Area=15.520 ac Peak Elev=369.33' Storage=69,952 cf 66.81 cfs 45.19 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 19HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 263P: GravelWet8 Inflow Area = 12.700 ac, Inflow Depth = 2.95" for 100 Year event Inflow = 51.90 cfs @ 12.05 hrs, Volume= 3.117 af Outflow = 28.98 cfs @ 12.17 hrs, Volume= 3.117 af, Atten= 44%, Lag= 7.5 min Primary = 28.98 cfs @ 12.17 hrs, Volume= 3.117 af Routing by Stor-Ind method, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Starting Elev= 330.67' Surf.Area= 18,000 sf Storage= 8,694 cf Peak Elev= 334.37' @ 12.17 hrs Surf.Area= 36,048 sf Storage= 57,900 cf (49,206 cf above start) Plug-Flow detention time= 344.9 min calculated for 2.917 af (94% of inflow) Center-of-Mass det. time= 281.7 min ( 1,102.5 - 820.8 ) Volume Invert Avail.Storage Storage Description #1 328.00' 8,388 cf Custom Stage Data (Prismatic) Listed below (Recalc) 20,970 cf Overall x 40.0% Voids #2 330.33' 603 cf Custom Stage Data (Prismatic) Listed below (Recalc) 6,030 cf Overall x 10.0% Voids #3 331.00' 51,235 cf Custom Stage Data (Prismatic) Listed below (Recalc) 60,226 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 328.00 9,000 0 0 330.33 9,000 20,970 20,970 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 330.33 9,000 0 0 331.00 9,000 6,030 6,030 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 331.00 9,000 0 0 332.00 13,677 11,339 11,339 333.00 15,480 14,579 25,917 334.00 17,340 16,410 42,327 334.50 18,291 8,908 51,235 Device Routing Invert Outlet Devices #1 Primary 330.67'18.0" Round Culvert L= 40.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 330.67' / 330.35' S= 0.0080 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf #2 Device 1 330.67'2.7" Vert. Orifice/Grate C= 0.600 #3 Device 1 331.20'1.0" Vert. Orifice/Grate C= 0.600 #4 Device 1 332.40'6.0" Vert. Orifice/Grate C= 0.600 #5 Device 1 333.00'48.0" W x 6.0" H Vert. Orifice/Grate C= 0.600 #6 Primary 333.50'8.0' long x 4.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 20HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef. (English) 2.38 2.54 2.69 2.68 2.67 2.67 2.65 2.66 2.66 2.68 2.72 2.73 2.76 2.79 2.88 3.07 3.32 Primary OutFlow Max=28.97 cfs @ 12.17 hrs HW=334.37' (Free Discharge) 1=Culvert (Inlet Controls 11.54 cfs @ 6.53 fps) 2=Orifice/Grate (Passes < 0.36 cfs potential flow) 3=Orifice/Grate (Passes < 0.05 cfs potential flow) 4=Orifice/Grate (Passes < 1.24 cfs potential flow) 5=Orifice/Grate (Passes < 10.18 cfs potential flow) 6=Broad-Crested Rectangular Weir (Weir Controls 17.43 cfs @ 2.50 fps) Pond 263P: GravelWet8 InflowPrimary Hydrograph Time (hours)12512011511010510095908580757065605550454035302520151050Flow (cfs)55 50 45 40 35 30 25 20 15 10 5 0 Inflow Area=12.700 ac Peak Elev=334.37' Storage=57,900 cf 51.90 cfs 28.98 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 21HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 265P: GravelWet4 Inflow Area = 7.080 ac, Inflow Depth = 3.53" for 100 Year event Inflow = 38.95 cfs @ 12.00 hrs, Volume= 2.081 af Outflow = 24.00 cfs @ 12.08 hrs, Volume= 2.081 af, Atten= 38%, Lag= 5.2 min Primary = 24.00 cfs @ 12.08 hrs, Volume= 2.081 af Routing by Stor-Ind method, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Starting Elev= 379.67' Surf.Area= 10,880 sf Storage= 5,255 cf Peak Elev= 383.70' @ 12.08 hrs Surf.Area= 23,111 sf Storage= 39,389 cf (34,134 cf above start) Plug-Flow detention time= 339.9 min calculated for 1.960 af (94% of inflow) Center-of-Mass det. time= 280.2 min ( 1,078.3 - 798.2 ) Volume Invert Avail.Storage Storage Description #1 377.00' 5,070 cf Custom Stage Data (Prismatic) Listed below (Recalc) 12,675 cf Overall x 40.0% Voids #2 379.33' 364 cf Custom Stage Data (Prismatic) Listed below (Recalc) 3,645 cf Overall x 10.0% Voids #3 380.00' 34,618 cf Custom Stage Data (Prismatic) Listed below (Recalc) 40,053 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 377.00 5,440 0 0 379.33 5,440 12,675 12,675 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 379.33 5,440 0 0 380.00 5,440 3,645 3,645 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 380.00 5,440 0 0 381.00 8,025 6,733 6,733 382.00 9,537 8,781 15,514 383.00 11,105 10,321 25,835 383.75 12,318 8,784 34,618 Device Routing Invert Outlet Devices #1 Primary 379.67'18.0" Round Culvert L= 15.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 379.67' / 378.00' S= 0.1113 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf #2 Device 1 379.67'2.5" Vert. Orifice/Grate C= 0.600 #3 Device 1 380.95'1.0" Vert. Orifice/Grate C= 0.600 #4 Device 1 382.10'48.0" W x 6.0" H Vert. Orifice/Grate C= 0.600 #5 Primary 383.00'8.0' long x 4.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 22HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Coef. (English) 2.38 2.54 2.69 2.68 2.67 2.67 2.65 2.66 2.66 2.68 2.72 2.73 2.76 2.79 2.88 3.07 3.32 Primary OutFlow Max=23.97 cfs @ 12.08 hrs HW=383.70' (Free Discharge) 1=Culvert (Passes 11.52 cfs of 12.16 cfs potential flow) 2=Orifice/Grate (Orifice Controls 0.33 cfs @ 9.53 fps) 3=Orifice/Grate (Orifice Controls 0.04 cfs @ 7.92 fps) 4=Orifice/Grate (Orifice Controls 11.15 cfs @ 5.58 fps) 5=Broad-Crested Rectangular Weir (Weir Controls 12.45 cfs @ 2.24 fps) Pond 265P: GravelWet4 InflowPrimary Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)42 40 38 36 34 32 30 28 26 24 22 20 18 16 14 12 10 8 6 4 2 0 Inflow Area=7.080 ac Peak Elev=383.70' Storage=39,389 cf 38.95 cfs 24.00 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 23HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 271P: GravelWet6A Inflow Area = 3.880 ac, Inflow Depth = 3.73" for 100 Year event Inflow = 23.37 cfs @ 11.98 hrs, Volume= 1.207 af Outflow = 10.79 cfs @ 12.08 hrs, Volume= 1.207 af, Atten= 54%, Lag= 6.1 min Primary = 10.79 cfs @ 12.08 hrs, Volume= 1.207 af Routing by Stor-Ind method, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Starting Elev= 375.67' Surf.Area= 7,300 sf Storage= 3,526 cf Peak Elev= 379.35' @ 12.08 hrs Surf.Area= 15,303 sf Storage= 24,263 cf (20,737 cf above start) Plug-Flow detention time= 356.9 min calculated for 1.126 af (93% of inflow) Center-of-Mass det. time= 287.0 min ( 1,076.5 - 789.5 ) Volume Invert Avail.Storage Storage Description #1 373.00' 3,402 cf Custom Stage Data (Prismatic) Listed below (Recalc) 8,504 cf Overall x 40.0% Voids #2 375.33' 245 cf Custom Stage Data (Prismatic) Listed below (Recalc) 2,446 cf Overall x 10.0% Voids #3 376.00' 21,800 cf Custom Stage Data (Prismatic) Listed below (Recalc) 25,446 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 373.00 3,650 0 0 375.33 3,650 8,504 8,504 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 375.33 3,650 0 0 376.00 3,650 2,446 2,446 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 376.00 3,650 0 0 377.00 5,622 4,636 4,636 378.00 6,595 6,109 10,745 379.00 7,624 7,110 17,854 379.50 8,160 3,946 21,800 Device Routing Invert Outlet Devices #1 Primary 375.67'18.0" Round Culvert L= 90.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 375.67' / 370.00' S= 0.0630 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf #2 Device 1 375.67'2.0" Vert. Orifice/Grate C= 0.600 #3 Device 1 376.90'1.0" Vert. Orifice/Grate C= 0.600 #4 Device 1 377.90'48.0" W x 6.0" H Vert. Orifice/Grate C= 0.600 Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 24HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Primary OutFlow Max=10.78 cfs @ 12.08 hrs HW=379.35' (Free Discharge) 1=Culvert (Passes 10.78 cfs of 11.50 cfs potential flow) 2=Orifice/Grate (Orifice Controls 0.20 cfs @ 9.14 fps) 3=Orifice/Grate (Orifice Controls 0.04 cfs @ 7.48 fps) 4=Orifice/Grate (Orifice Controls 10.54 cfs @ 5.27 fps) Pond 271P: GravelWet6A Inflow Primary Hydrograph Time (hours)12512011511010510095908580757065605550454035302520151050Flow (cfs)26 24 22 20 18 16 14 12 10 8 6 4 2 0 Inflow Area=3.880 ac Peak Elev=379.35' Storage=24,263 cf 23.37 cfs 10.79 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 25HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Pond 277P: GravelWet6B Inflow Area = 5.320 ac, Inflow Depth = 3.63" for 100 Year event Inflow = 29.10 cfs @ 12.00 hrs, Volume= 1.609 af Outflow = 11.44 cfs @ 12.14 hrs, Volume= 1.609 af, Atten= 61%, Lag= 8.2 min Primary = 11.44 cfs @ 12.14 hrs, Volume= 1.609 af Routing by Stor-Ind method, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Starting Elev= 332.17' Surf.Area= 10,260 sf Storage= 4,956 cf Peak Elev= 335.80' @ 12.14 hrs Surf.Area= 21,563 sf Storage= 33,358 cf (28,402 cf above start) Plug-Flow detention time= 350.1 min calculated for 1.495 af (93% of inflow) Center-of-Mass det. time= 278.9 min ( 1,074.3 - 795.4 ) Volume Invert Avail.Storage Storage Description #1 329.50' 4,781 cf Custom Stage Data (Prismatic) Listed below (Recalc) 11,953 cf Overall x 40.0% Voids #2 331.83' 344 cf Custom Stage Data (Prismatic) Listed below (Recalc) 3,437 cf Overall x 10.0% Voids #3 332.50' 30,552 cf Custom Stage Data (Prismatic) Listed below (Recalc) 35,677 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 329.50 5,130 0 0 331.83 5,130 11,953 11,953 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 331.83 5,130 0 0 332.50 5,130 3,437 3,437 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 332.50 5,130 0 0 333.00 6,813 2,986 2,986 334.00 8,365 7,589 10,575 335.00 9,975 9,170 19,745 336.00 11,640 10,808 30,552 Device Routing Invert Outlet Devices #1 Primary 332.17'24.0" Round Culvert L= 284.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 332.17' / 330.75' S= 0.0050 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 3.14 sf #2 Device 1 332.17'2.2" Vert. Orifice/Grate C= 0.600 #3 Device 1 333.25'1.0" Vert. Orifice/Grate C= 0.600 #4 Device 1 334.20'48.0" W x 6.0" H Vert. Orifice/Grate C= 0.600 Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 26HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Primary OutFlow Max=11.44 cfs @ 12.14 hrs HW=335.80' (Free Discharge) 1=Culvert (Passes 11.44 cfs of 18.87 cfs potential flow) 2=Orifice/Grate (Orifice Controls 0.24 cfs @ 9.05 fps) 3=Orifice/Grate (Orifice Controls 0.04 cfs @ 7.62 fps) 4=Orifice/Grate (Orifice Controls 11.16 cfs @ 5.58 fps) Pond 277P: GravelWet6B Inflow Primary Hydrograph Time (hours)12512011511010510095908580757065605550454035302520151050Flow (cfs)32 30 28 26 24 22 20 18 16 14 12 10 8 6 4 2 0 Inflow Area=5.320 ac Peak Elev=335.80' Storage=33,358 cf 29.10 cfs 11.44 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 27HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Link 245L: Sn004 Inflow Area = 6.550 ac, Inflow Depth = 3.84" for 100 Year event Inflow = 19.20 cfs @ 12.15 hrs, Volume= 2.094 af Primary = 19.20 cfs @ 12.15 hrs, Volume= 2.094 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Link 245L: Sn004 Inflow Primary Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Inflow Area=6.550 ac 19.20 cfs19.20 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 28HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Link 246L: Sn006 Inflow Area = 7.080 ac, Inflow Depth = 3.53" for 100 Year event Inflow = 24.00 cfs @ 12.08 hrs, Volume= 2.081 af Primary = 24.00 cfs @ 12.08 hrs, Volume= 2.081 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Link 246L: Sn006 Inflow Primary Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)26 24 22 20 18 16 14 12 10 8 6 4 2 0 Inflow Area=7.080 ac 24.00 cfs24.00 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 29HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Link 247L: Sn007 Inflow Area = 15.520 ac, Inflow Depth = 3.23" for 100 Year event Inflow = 45.19 cfs @ 12.16 hrs, Volume= 4.177 af Primary = 45.19 cfs @ 12.16 hrs, Volume= 4.177 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Link 247L: Sn007 Inflow Primary Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)50 48 46 44 42 40 38 36 34 32 30 28 26 24 22 20 18 16 1412 10 8 6 4 2 0 Inflow Area=15.520 ac 45.19 cfs45.19 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 30HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Link 248L: Sn009 Inflow Area = 4.090 ac, Inflow Depth = 3.23" for 100 Year event Inflow = 1.24 cfs @ 12.92 hrs, Volume= 1.101 af Primary = 1.24 cfs @ 12.92 hrs, Volume= 1.101 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Link 248L: Sn009 Inflow Primary Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)1 0 Inflow Area=4.090 ac 1.24 cfs1.24 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 31HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Link 249L: Sn010 Inflow Area = 12.700 ac, Inflow Depth = 2.95" for 100 Year event Inflow = 28.98 cfs @ 12.17 hrs, Volume= 3.117 af Primary = 28.98 cfs @ 12.17 hrs, Volume= 3.117 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Link 249L: Sn010 Inflow Primary Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)32 30 28 26 24 22 20 18 16 14 12 10 8 6 4 2 0 Inflow Area=12.700 ac 28.98 cfs28.98 cfs Type II 24-hr 100 Year Rainfall=4.85"Eastview2022-post Printed 4/7/2022Prepared by Krebs & Lansing Consulting Engineers, Inc. Page 32HydroCAD® 10.00 s/n 06429 © 2013 HydroCAD Software Solutions LLC Summary for Link 278L: Sn008 Inflow Area = 9.200 ac, Inflow Depth = 3.67" for 100 Year event Inflow = 22.05 cfs @ 12.11 hrs, Volume= 2.815 af Primary = 22.05 cfs @ 12.11 hrs, Volume= 2.815 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-128.00 hrs, dt= 0.01 hrs Link 278L: Sn008 Inflow Primary Hydrograph Time (hours) 12512011511010510095908580757065605550454035302520151050Flow (cfs)24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Inflow Area=9.200 ac 22.05 cfs22.05 cfs