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4 - Pleasant View Pointe - SMWP - 4-18-25Stormwater Management Hydrologic and Hydraulic Study Pleasant View Pointe Chanhassen, MN City of Chanhassen Minnehaha Creek Watershed District April 18, 2025 Pleasant View Pointe Development Hydrologic and Hydraulic Study 4/18/2025 Alliant Engineering, Inc. Page 1 of 9 221-0203 Introduction Included in this report are the materials necessary to review the stormwater management plan for the proposed “Pleasant View Pointe” project in Chanhassen, Minnesota. The following information is included: • Study Narrative • Stormwater Wetland Zone Classifications • Drainage Area Maps • Rate Control HydroCAD Calculation Reports • Water Quality Calculations: o Proposed MIDS estimating pond phosphorous and TSS removal efficiency. o Water Quality Treatment Area Map • Volume Control Calculations • Volume Control Treatment Exhibit • Geotechnical Soil Borings Background This study was conducted to analyze the stormwater treatment requirements for a proposed residential subdivision in Chanhassen, MN and within Minnehaha Creek Watershed District (MCWD) boundary. The study will show that the proposed stormwater management system will nullify the effects of the increased impervious cover resulting from the new development. The study assumes the following two scenarios: • Existing conditions – Single Residence occupying property. • Proposed conditions – Development of the residential project. o City of Chanhassen Urban Improvements of Pleasant View Lane and Installation of storm sewer. Project Area Total Site Area based on boundary (acres) 14.560 Total Proposed SWMP Area including Offsite Area (acres) 24.134 Existing Site Impervious (acres) 0.443 Post Construction Site Impervious (acres) 4.472 Proposed (future) Pleasant View Road Impervious 1.099 Proposed (future) Peaceful Lane Road 0.231 Total Volume Control Impervious Area (acres) * 5.802 Impervious Area Routed to North BMP (acres)** 5.119 Impervious Area Routed to West BMP (acres) 0.683 *Total volume control area impervious is the proposed impervious created from the development site. Proposed homes, and roads. Additionally, volume controlled impervious for proposed future Pleasant View Road. **The impervious area listed here is the portion of required impervious required by the watershed and the city to be treated. There is additional existing imperious that is routed to the north BMP. Pleasant View Pointe Development Hydrologic and Hydraulic Study 4/18/2025 Alliant Engineering, Inc. Page 2 of 9 221-0203 Runoff Rate Control All rate control calculations have been performed using the method via HydroCAD software. Three events were modeled including: the 2-year, 10-year and 100-year, MSE Type 3 24-hour storm events, AMC 2, with ATLAS-14 precipitation amounts of 2.87”, 4.28”, and 7.38”, used respectively. All existing and proposed curve numbers are based on estimations of land cover and soil type from attached geotechnical report. Based on the soil borings from Geotechnical Analysis, an aggregate hydrologic soil group of “D” was assumed throughout the site. Times of concentrations were typically estimated and modeled using direct entry and lag method. Existing Conditions The project site is currently 5 parcels, with 1 single family residence, driveway, and outbuildings. The development site is located South of Christmas Lake. A portion of the site does fall withing the 1,000’ shoreland district for Christmas Lake. The site consists of wooded uplands and grassed areas, existing stormwater pond, historic remnant wetland, and incidental wetland. The project does contain bluff as defined by the City of Chanhassen code. The property has variable slopes from flat to more than 3:1. Roughly ½ of the site drains via overland or storm sewer to the existing pond. The existing pond was modified with the development of the Treondle Addition. A majority of the Treondle Addition does drain to the existing pond via storm sewer. The existing pond/wetland outlets via 8” pipe to the west to existing preserve wetland as defined by MCWD. A small portion of the site NE drains to Exiting Pleasant View lane and continues East. A small portion drains east offsite. A portion drains south through existing residential to Lake Lucy Road. A portion drains overland to the west down to a ditch that swales and drains to a low point culvert. The culvert then outlets west towards the existing preserve wetland. Wetland 1 was determined to be incidental and will be graded and removed. The historic remnant wetland will remain in place except a small portion of 1268 sf will be filled. The wetland has been permitted to be impacted completely and will be mitigated offsite. In effort to preserve and satisfy the city of Chanhassen code, the remnant wetland is being incorporated into the proposed BMP. • E-1 – Onsite area that drains overland to the existing onsite remnant wetland/pond. • E-2 – Onsite area that drains overland to existing Troendle Additon storm sewer proceeding to the existing remnant wetland/onsite pond. • E-3 – Onsite area that drains overland to the South through existing residential, proceeding to Lake Lucy Road Storm Sewer. • E-4 - Onsite area that drains West overland to a ditch that swales and drains to a low point culvert. The culvert outlets and drains to an existing offsite preserve wetland. • E-5 – Onsite area that drains overland offsite to Exiting Pleasant View lane and continues East • E-6 – Onsite area that drains East to existing residential area. • E-7 – Onsite area that drains overland to existing Troendle Additon storm sewer proceeding to the existing onsite remnant wetland/pond. • E-8 – Onsite pervious area that drains overland West to existing offsite preserve wetland. • OFF-1 – Offsite Trendle Addition residential single family homes and roadways that drain via storm sewer to the onsite existing remnant wetland/pond. • OFF-2 – Offsite residential that drains overland to the existing remnant wetland/pond. • OFF-3 – Offsite residential and Pleasant View Drive that drains via roadway and ditches to the existing onsite remnant wetland/pond. • OFF-4 – Offsite existing residential and Peaceful Lane roadway that drains to the existing offsite preserve wetland to the West. • OFF-5 – Offsite pervious area drains West overland to a ditch that swales and drains to a low point culvert. The culvert outlets and drains to an existing offsite preserve wetland. Pleasant View Pointe Development Hydrologic and Hydraulic Study 4/18/2025 Alliant Engineering, Inc. Page 3 of 9 221-0203 • OFF-6 – Offsite area that drains onto the site overland and proceeds South to Lake Lucy Road Storm Sewer. To compare peak discharge rates for the existing and proposed conditions, flows were analyzed compositely. Refer to the existing conditions drainage map and HydroCAD report for additional information and detailed calculations. Site composite existing runoff rate as calculated by HydroCAD are listed in the table below: Proposed Conditions The proposed development area is made up of 5 existing parcels totaling in 13.60 acres. The parcels are split in the middle by existing public ROW intended to connect Nez Pierce Drive and Peacefule Lane. The ROW splitting the parcels will be vacated (included in new site area) and new road ROW will be provided. The site is bound by existing residential properties to the east and south. The property is then bound on the west and north by a two roads and public ROW. A portion of the existing ROW along the old Redman Lane has a resolution to be vacated from 1987 (see survey and plan). This ROW will be vacated and given back to abutting landowner and is included in site area. The total site area included to be platted with new ROW is 14.56 AC. Rachel Development is proposing 20 new residential single-family homes. Drainage maps provided show delineations based on full development. The site is capturing and treating all new created imperious from the site. The city will be re-constructing Pleasant View Road in the future. An assumed city street section 31’ back to back with a 10’ wide trail. Additionally a new/additional area that can be captured by storm sewer and piped back to the new north BMP has been added to the plan. The assumptions used is a 4’ minimum starting build, with 0.5% slope to the NWL of 994.0. The below screen shot shows blue hatched area, the new area added to the proposed conditions of the modeling and is included. The added area will now show greater areas than the existing conditions and will not match. Event South (cfs) West (cfs) North East (cfs) East (cfs) Total (cfs) 2 year (2.87” 24hr) 4.80 8.54 1.01 0.59 14.94 10 year (4.28” 24hr) 9.32 13.92 1.99 1.16 26.39 100 year (7.33” 24hr) 20.13 24.06 4.35 2.53 51.07 Pleasant View Pointe Development Hydrologic and Hydraulic Study 4/18/2025 Alliant Engineering, Inc. Page 4 of 9 221-0203 The stormwater management plan for the proposed conditions will meet the guidelines required by the City of Chanhassen and Minnehaha Creek Watershed District (MCWD) for stormwater rate and volume control. The following criterion was used in designing the stormwater management system: • Post-development peak runoff rate from the site for the 2, 10 and 100-year 24-hour MSE 3 24-hour storm events (Hershfield, DM. 1961 rainfall frequency.) must not be greater than existing condition rates in accordance with the City and. To remain conservative, Alliant used the (Atlas 14) rainfall data for modeling purposes. • Development may not increase the peak runoff rate from the site, in aggregate for the design rainfall events. • Newly constructed stormwater BMP, shall provide water quality volume treatment in accordance with criteria 90 percent TSS removal and 60 percent TP removal. • Provide volume control equivalent to 1.0” of runoff from all proposed impervious surface, in accordance with MCWD volume control requirements. If filtration is used as BMP volume provided must be twice the required volume reduction. • Freeboard, the lowest building opening must be at minimum 1’ above the emergency over flow elevation. Building adjacent to stormwater basin shall be 3’ above the 100 year high water level (HWL). • Impact to Downstream waterbodies receiving runoff shall be in accordance with MCWD. The proposed residential development will consist of 20 single family homes and associated roadways as shown in the plan set. The project will include one stormwater wetland with a filtration bench and one filtration basin to provide rate and volume control, for treatment of the stormwater runoff. The filtration basin to the west will have pre-treatment provided by overland drainage. Stormwater runoff from the new roadways, and most of the front and rear yards will be collected by storm sewer and piped to the proposed north stormwater treatment BMP. Some of the rear yards will run directly into the BMP. 5 rear yards will run west to the filtration basin. The proposed stormwater that was being collected for Troendle Additon is still being collected via stormsewer and routed to the proposed stormwater wetland/filtration basin. The proposed basin will be capturing, the OFF-4 that previously drained West toward the existing pond. Most of the area that previously drained south to Lake Lucy Road is being captured and will run to the proposed north BMP via storm sewer. The following HydroCAD sub catchments were used in the proposed conditions model: • S-1 - Onsite area that drains overland and unconnected to the proposed BMP • S-2 - Onsite area that drains to stormsewer and then to the proposed BMP. • S-3 – Onsite pervious area that drains overland to the South through existing residential, proceeding to Lake Lucy Road storm sewer. • S-4 – Onsite area that drains overland to the West to a proposed filtration basin. • S-5 - Onsite area that drains overland offsite to Exiting Pleasant View lane and will be captured with the City’s Pleasant View Road re-construction storm sewer. • S-6 - Onsite pervious area that drains East to existing residential area. • S-7 – Onsite pervious area that drains overland west to existing wetland. • S-9 – Onsite pervious area that drains overland west to existing wetland. • OFF-1 – Offsite existing Trendle Addition residential single family homes and roadways that drain via storm sewer to the onsite proposed BMP. • OFF-2 – Offsite residential that drains overland to the proposed BMP. • OFF-3 – Offsite residential and Proposed Pleasant View Drive that drains via roadway and ditches and future storm sewer to a low point proposed catch basin and rip rap forebay to and proposed BMP. The impervious area included here includes the future city road and trail. Pleasant View Pointe Development Hydrologic and Hydraulic Study 4/18/2025 Alliant Engineering, Inc. Page 5 of 9 221-0203 • OFF-4 – Offsite existing residential and Peaceful Lane roadway that is now captured via stormsewer and drains to the proposed BMP. • OFF-5 – Offsite pervious area drains overland to the proposed West filtration basin. • OFF-6 – Offsite area that drains overland to stormsewer that is directed to the north BMP. This area previously drained to the south to Lake Lucy Road storm sewer. • OFF – 7 – offsite area that drains overland to the north BMP. This area newly captured by the site due to proposed grading. Previously drained onto the site then south and east with S6 area. • OFF – 8 – offsite area that can be captured by newly constructed Pleasant View Road construction and storm sewer. Area previously drained to the east away from project. • OFF – 9 – offsite area that can be captured by newly constructed Pleasant View Road construction and storm sewer. Area previously drained to the west away from project. Most of the runoff from the site’s developed area will be routed to the proposed BMP stormwater wetland with a filtration bench and underdrain or a filtration basin to the west. The filtration bench will provide the required filtration volume required by the city and watershed. The BMPs have an OCS (Outlet Control Structure) that will be used to provide a controlled discharge rate to the existing west wetland offsite. The outlet for the proposed pond will be installed in the same location and have the same elevation as the existing pond outlet. The proposed stormwater management plan decreases the composite peak discharge rate for all stormwater events to below existing conditions. The proposed stormwater plan also decreases to 3 of the 4 individual discharge points and removed the NE discharge point. Refer to the proposed conditions drainage map and HydroCAD report sheets for additional information. Site composite proposed runoff rate as calculated by HydroCAD are listed in the table below: Stormwater Volume Control Required Volume The project is required to provide volume control in accordance with the MCWD criteria. Volume control equivalent to 1” over the proposed impervious surface is required. The volume control shall be taken care of by infiltration unless deemed in-feasible. The site soils are primarily made up of Hydraulic Soil Group D soils (sandy lean clay (CL), clayey sands (SC). Per watershed stormwater management rule 3.b.5, infiltration shall not be used. The volume control requirement is being met through filtration. The total new proposed impervious surface from proposed roadways, driveways, buildings, is 194,783 sf (4.472 AC). The new proposed site impervious is the actual new road impervious, and the maximum amount of impervious per lot. The shown home foortprints, and dirveways are sample and will be customized per each lot. Conservatively the maximum allowed imperious per lot was used to determine the required treatment volume, not what is shown on the plan. Required treatment volume for the site is equal to 16,232 cubic feet. MCWD requires filtration bmp to provided twice the required volume to be provided. The required volume control for the development site is 32,463 cubic feet. Additional Required Volume The city will be re-constructing Pleasant View Road and will be installing storm sewer to capture the re- constructed road. An analysis has been completed to determine the extents to what can be captured by the storm sewer. The new road area has been assumed to be 31’ back to back road with 10’ trail. Impervious to be treated for Pleasant View Road section is 47,867 sf (1.099 AC). Also, Peaceful lane will be re-constructed Event South (cfs) West (cfs) North East (cfs) East (cfs) Total (cfs) 2 year (2.87” 24hr) 0.34 3.81 0 0.25 4.40 10 year (4.28” 24hr) 0.65 12.85 0 0.50 14.00 100 year (7.33” 24hr) 1.38 22.59 0 1.07 25.04 Pleasant View Pointe Development Hydrologic and Hydraulic Study 4/18/2025 Alliant Engineering, Inc. Page 6 of 9 221-0203 in coordination with the City of Chanhassen. This adds, 10,072 sf (0.231 AC), impervious road. The required treatment volume for Peaceful Lane and Pleasant View road is 4,828 CF x 2 (MCWD) 9,656.44 CF Total Required Water Quality Volume 42,120 CF Proposed Volume The total treatment volume provided is equal to 51,511.00 CF. Stormwater Wetland / Filtration Bench There is 47,643 CF provided by the north Stormwater Wetland. The filtration volume is set by the OCS orifice withing wier wall set at 995.0. Details of the OCS can be found in the proposed development plans. A volume table of the proposed BMP is included in this report to show the volume difference from the 995 to the 994 contours, thus indicating the provided filtration volume. The filtration depth is 1.0’. The 47,643 cf will filter through a 10,056 sf media mix c section to an underdrain system. Filtration Basin 2 There is 3,868 CF provided treatment volume by the West Filtration Basin. The filtration volume is set by the OCS notch in wier wall set at 996.0. Details of the OCS can be found in the proposed development plans. The filtration Depth is 2.0’. The 3,868 CF will filter through 1,035 sf media mix c section to an underdrain system. Proposed Underdrain The underdrain will be installed per city of Chanhassen standard details and the MN stormwater manual. The quantity of underdrain is determined by the Carver County watershed design criteria of 1 lf of draintile per 50 cf of ponded filtration volume. See the development plans for further details on the proposed filtration section and underdrain. Stormwater Wetland / Filtration Bench Required draintile is equal to 47,643 CF /1LF 50 cf = 953 LF. Filtration Basin 2 Required draintile is equal to 3,868 CF /1LF 50 cf = 78 LF. Filtration Basin Draw Down Calculation The filtration basin will draw down within 48 hours per MPCA guidelines. The assumed infiltration rate of media mix c is 0.8in/hr. The infiltration rate of 0.8in/hr is a conservative estimate and will likely be the filtration rate over time. Per the MPCA an infiltration rate of 1.63in/hr can be used for sand. Basin Filtration Volume Filtration Depth Draw Down Time Stormwater Wetland /Filtration 47,643 1.0’ 15 hr Filtration Basin 2 3,868 2.0’ 30 hr 𝑷𝒓𝒎𝒎𝒎𝒓𝒄𝒄 𝑫𝒓𝒂𝒘 𝑫𝒎𝒘𝒎 𝒄𝒎𝒎𝒎𝒓𝒓𝒂𝒓𝒉𝒎𝒎. 𝟎𝟎 𝒉𝒎 ÷ 𝟎.𝟖𝒉𝒎 𝒉𝒓 =𝟎𝟎 𝒉𝒓 𝑴𝒂𝒘𝒉𝒎𝒓𝒎 𝑫𝒓𝒂𝒘 𝑫𝒎𝒘𝒎 𝒄𝒎𝒎𝒎𝒓𝒓𝒂𝒓𝒉𝒎𝒎. 𝟎𝟖.𝟎 𝒉𝒎 ÷ 𝟎.𝟖𝒉𝒎 𝒉𝒓 =𝟎𝟖 𝒉𝒓 Pleasant View Pointe Development Hydrologic and Hydraulic Study 4/18/2025 Alliant Engineering, Inc. Page 7 of 9 221-0203 Stormwater Quality The stormwater management system must have an 90% TSS and 60% Phosphorus removal efficiency from proposed conditions. MIDS Calculator was used to calculate TSS and TP removal efficiencies. See the MIDS Results for reference. The onsite area totaling and proposed Peaceful Lane and Pleasant View Road. 14.56 AC + 1.33 = 15.89 AC. TSS and TP removal efficiencies as calculated by MIDS Calculator (Site and Pleasant View Imp.: Total Proposed TSS Removal Efficiency Proposed P Removal Efficiency Site Removal 95% 65% Troendle Addition Although not necessary to be treated, a MIDS model was created to analyze what the treatment of the Offsite Toendle Addition would be. Below are the This is OFF-1 sub catchment. The MIDS still show that the system is treating above the required 90% TSS and 60% TP removal efficiencies. TSS and TP removal efficiencies as calculated by MIDS Calculator (Site and Pleasant View Imp.: Total Proposed TSS Removal Efficiency Proposed P Removal Efficiency Site Removal 95% 64% Entire SWM Site Area Although not necessary to be treated, a MIDS model was created to analyze what the treatment of the entire SWM area of 24.134 AC. Below are the This is OFF-1 sub catchment. The MIDS still show that the system is treating above the required 90% TSS and 60% TP removal efficiencies. TSS and TP removal efficiencies as calculated by MIDS Calculator (Site and Pleasant View Imp.: Total Proposed TSS Removal Efficiency Proposed P Removal Efficiency Site Removal 95% 63% Impact on Downgradient Waterbodies Per MCWD wetland inventory, there are 3 wetlands that receive runoff from the site. Existing wetland to the west is a preserve wetland per the MCWD. Per wetland rules the permitted bounce for storm event is existing for a preserve wetland. To determine that the site meets the requirements, lidar contours were used to model the existing wetland. The normal water level was surveyed at an elevation of 974.1. An 18” standpipe was observed and recorded to be the outlet for the preserve wetland. The model only takes into consideration the project site drainage area. See below the results from the existing and proposed conditions for the bounce. Event Existing HWL Proposed HWL 2 year (2.87” 24hr) 974.35 974.30 10 year (4.28” 24hr) 974.48 974.41 100 year (7.33” 24hr) 974.85 974.82 Pleasant View Pointe Development Hydrologic and Hydraulic Study 4/18/2025 Alliant Engineering, Inc. Page 8 of 9 221-0203 Existing Wetland to SE of catchment S6 is a preserve wetland per MCWD. The total area and flow to the East was reduced in all storm events; therefore, does not create a bounce on the downstream wetland. No new impervious is created that flows to the east from catchment S6. See below results of existing and proposed volumes. Existing Wetland to South of catchment S3 is a manage 1 wetland per MCWD. The total area and flow to the South was significantly reduced in all storm events; therefore, does not create a bounce on the downstream wetland. No new impervious is created that flows to the south from catchment S3. See below results of existing and proposed volumes. Conclusion Alliant Engineering believes that the proposed design is acceptable for all parties involved. The peak discharge rates for the 2-year, 10-year and 100-year 24-hour storm events will be decreased in aggregate from existing rates for the proposed conditions. Sufficient runoff volume control has been provided by the stormwater management system to mitigate the proposed impervious surface additions. The proposed stormwater management system meets the TSS and TP removal efficiency requirements. Finally, the proposed grading and SWPPP plans will utilize Best Management Practices whenever possible to provide adequate erosion control measures to contain sediment during construction. Please call me at 612-767-9330 with any questions or comments regarding stormwater issues for the Pleasant View Pointe Development project. Sincerely, Tyler Stricherz, PE Alliant Engineering, Inc. CC: File 4000320 Event Existing Volume (AC-FT) Proposed Volume (AC-FT) 2 year (2.87” 24hr) 0.024 0.010 10 year (4.28” 24hr) 0.047 0.019 100 year (7.33” 24hr) 0.107 0.043 Event Existing Volume (AC-FT) Proposed Volume (AC-FT) 2 year (2.87” 24hr) 0.227 0.013 10 year (4.28” 24hr) 0.440 0.026 100 year (7.33” 24hr) 0.978 0.058 Pleasant View Pointe Development Hydrologic and Hydraulic Study 4/18/2025 Alliant Engineering, Inc. Page 9 of 9 221-0203 APPENDIX - Stormwater Wetland Zone Classifications - Rate Control Supporting Documents ▪ Drainage Delineation Maps • Existing Conditions • Proposed Conditions ▪ Rate Control HydroCAD Reports • Existing Conditions • Proposed Conditions - Water Quality Supporting Calculations • Proposed MIDS Calculator - Volume Control Supporting Documents ▪ HydroCAD Filtration Volume - Storm Sewer Spreadsheet - Geotechnical Analysis PLEASANT VIEW RD 3 7 56 BLOCK 1 STORMWATER WETLAND/FILTRATION NWL:994.0 100 YEAR HWL:999.86 PEACEFUL LANEFile Location: X:\4000320-00\001\30 Exhibits\Stormwater Wetland Area Map.dwg Plotted By: Tyler Stricherz on April 18, 2025 at 11:59:05 AM PLEASANT VIEW POINTE - CONSTRUCTED WETLAND - ZONE CLASSIFICATIONS File Location: X:\4000320-00\001\30 Exhibits\Stormwater Wetland Area Map.dwg Plotted By: Tyler Stricherz on April 18, 2025 at 11:59:05 AM GU File Location: X:\4000320-00\001\40 Design\45 Stormwater\HYDRO-X-1.dwg Plotted By: Tyler Stricherz on April 18, 2025 at 8:07:07 AMKnow what's below. Call before you dig. R Dial 811 FOR R E VI E W O N L Y PRE LI MI N A R Y NOT F O R C O N S T R U C TI O N 0 SCALE IN FEET 35 70 140 N W S E PRELIMINARY PLAT CIT SUBMITTALFINAL PLAT - CITY SUBMITTAL 4-18-202512-19-2024 1 1 CHANHASSEN, MNPLEASANT VIEW POINTEEXISTING DRAINAGE MAPwww.alliant-inc.com PROJECT TEAM DATA QA/QC CHECK DateBy CERTIFICATION Date License no.DATEDESCRIPTIONProject No.: Drafted By: Designed By: Sheet of TAS I hereby certify that this plan, specification, or report was prepared by me or under my direct supervision and that I am a duly Licensed Professional Engineer under the laws of the State of Minnesota. 1 1 LEGEND E1 E1 E2 E2 E3 E3 E4 E4 E5 E5 E6 E6 E7 E7 E8 E8 OFF-1 OFF-1 OFF-2 OFF-2 OFF-3 OFF-3 OFF-4 OFF-4 OFF-5 OFF-5 OFF-6 OFF-6 1P EXISTING POND 2P West Ditch 10P West Exisitng Wetland 3L SOUTH OVERLAND 5L NE OVERLAND 6L EAST OVERLAND 7L TOTAL Routing Diagram for EDRN Prepared by Alliant Engineering, Inc, Printed 4/18/2025 HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Subcat Reach Pond Link EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 2HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Project Notes EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 3HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Rainfall Events Listing (selected events) Event# Event Name Storm Type Curve Mode Duration (hours) B/B Depth (inches) AMC 1 2-Year MSE 24-hr 3 Default 24.00 1 2.87 2 2 10-Year MSE 24-hr 3 Default 24.00 1 4.26 2 3 100-Year MSE 24-hr 3 Default 24.00 1 7.38 2 EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 4HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Area Listing (all nodes) Area (acres) CN Description (subcatchment-numbers) 10.733 80 >75% Grass cover, Good, HSG D (E1, E2, E3, E7, OFF-4, OFF-6) 0.040 98 Impervious, HSG D (OFF-6) 2.378 98 Paved parking, HSG D (E7, OFF-1, OFF-3, OFF-4) 0.517 98 Unconnected roofs, HSG D (E1, E2, E4, OFF-2) 0.555 98 Water Surface, HSG D (E1) 0.206 82 Woods/grass comb., Fair, HSG D (OFF-5) 7.066 79 Woods/grass comb., Good, HSG D (E4, E5, E6, OFF-1, OFF-2, OFF-3) 0.255 86 Woods/grass comb., Poor, HSG D (E8) 21.749 83 TOTAL AREA EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 5HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Soil Listing (all nodes) Area (acres) Soil Group Subcatchment Numbers 0.000 HSG A 0.000 HSG B 0.000 HSG C 21.749 HSG D E1, E2, E3, E4, E5, E6, E7, E8, OFF-1, OFF-2, OFF-3, OFF-4, OFF-5, OFF-6 0.000 Other 21.749 TOTAL AREA EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 6HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Ground Covers (all nodes) HSG-A (acres) HSG-B (acres) HSG-C (acres) HSG-D (acres) Other (acres) Total (acres) Ground Cover Subcatchment Numbers 0.000 0.000 0.000 10.733 0.000 10.733 >75% Grass cover, Good E1, E2, E3, E7, OFF-4, OFF-6 0.000 0.000 0.000 0.040 0.000 0.040 Impervious OFF-6 0.000 0.000 0.000 2.378 0.000 2.378 Paved parking E7, OFF-1, OFF-3, OFF-4 0.000 0.000 0.000 0.517 0.000 0.517 Unconnected roofs E1, E2, E4, OFF-2 0.000 0.000 0.000 0.555 0.000 0.555 Water Surface E1 0.000 0.000 0.000 0.206 0.000 0.206 Woods/grass comb., Fair OFF-5 0.000 0.000 0.000 7.066 0.000 7.066 Woods/grass comb., Good E4, E5, E6, OFF-1, OFF-2, OFF-3 0.000 0.000 0.000 0.255 0.000 0.255 Woods/grass comb., Poor E8 0.000 0.000 0.000 21.749 0.000 21.749 TOTAL AREA MSE 24-hr 3 2-Year Rainfall=2.87"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 7HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Time span=0.00-600.00 hrs, dt=0.01 hrs, 60001 points Runoff by SCS TR-20 method, UH=SCS, Weighted-Q Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Peak Elev=994.34' Storage=49,921 cf Inflow=32.63 cfs 1.778 afPond 1P: EXISTING POND 8.0" Round Culvert n=0.010 L=324.0' S=0.0080 '/' Outflow=1.53 cfs 1.775 af Peak Elev=995.91' Storage=27 cf Inflow=5.80 cfs 0.314 afPond 2P: West Ditch Primary=5.80 cfs 0.314 af Secondary=0.00 cfs 0.000 af Outflow=5.80 cfs 0.314 af Peak Elev=974.35' Storage=19,094 cf Inflow=8.54 cfs 2.203 afPond 10P: West Exisitng Wetland Outflow=1.92 cfs 2.203 af MSE 24-hr 3 2-Year Rainfall=2.87"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 8HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Summary for Pond 1P: EXISTING POND Inflow Area = 14.909 ac, 19.70% Impervious, Inflow Depth = 1.43" for 2-Year event Inflow = 32.63 cfs @ 12.15 hrs, Volume= 1.778 af Outflow = 1.53 cfs @ 13.62 hrs, Volume= 1.775 af, Atten= 95%, Lag= 88.4 min Primary = 1.53 cfs @ 13.62 hrs, Volume= 1.775 af Routed to Pond 10P : West Exisitng Wetland Routing by Dyn-Stor-Ind method, Time Span= 0.00-600.00 hrs, dt= 0.01 hrs Peak Elev= 994.34' @ 13.62 hrs Surf.Area= 36,001 sf Storage= 49,921 cf Plug-Flow detention time= 573.3 min calculated for 1.775 af (100% of inflow) Center-of-Mass det. time= 573.0 min ( 1,370.5 - 797.5 ) Volume Invert Avail.Storage Storage Description #1 992.61' 277,554 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 992.61 24,173 0 0 994.00 31,142 38,444 38,444 996.00 59,569 90,711 129,155 998.00 88,830 148,399 277,554 Device Routing Invert Outlet Devices #1 Primary 992.61'8.0" Round Culvert L= 324.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 992.61' / 990.02' S= 0.0080 '/' Cc= 0.900 n= 0.010 PVC, smooth interior, Flow Area= 0.35 sf Primary OutFlow Max=1.53 cfs @ 13.62 hrs HW=994.34' TW=974.35' (Dynamic Tailwater) 1=Culvert (Barrel Controls 1.53 cfs @ 4.39 fps) MSE 24-hr 3 2-Year Rainfall=2.87"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 9HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Pond 1P: EXISTING POND Inflow Primary Hydrograph Time (hours) 600550500450400350300250200150100500Flow (cfs)36 34 32 30 28 26 24 22 20 18 16 14 12 10 8 6 4 2 0 Inflow Area=14.909 ac Peak Elev=994.34' Storage=49,921 cf 8.0" Round Culvert n=0.010 L=324.0' S=0.0080 '/' 32.63 cfs 1.53 cfs MSE 24-hr 3 2-Year Rainfall=2.87"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 10HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 1P: EXISTING POND Time (hours) Inflow (cfs) Storage (cubic-feet) Elevation (feet) Primary (cfs) 0.00 0.00 0 992.61 0.00 20.00 0.36 32,465 993.80 1.23 40.00 0.00 3,678 992.76 0.06 60.00 0.00 1,642 992.68 0.01 80.00 0.00 1,045 992.65 0.01 100.00 0.00 764 992.64 0.00 120.00 0.00 601 992.63 0.00 140.00 0.00 496 992.63 0.00 160.00 0.00 421 992.63 0.00 180.00 0.00 366 992.63 0.00 200.00 0.00 324 992.62 0.00 220.00 0.00 291 992.62 0.00 240.00 0.00 265 992.62 0.00 260.00 0.00 243 992.62 0.00 280.00 0.00 225 992.62 0.00 300.00 0.00 209 992.62 0.00 320.00 0.00 196 992.62 0.00 340.00 0.00 184 992.62 0.00 360.00 0.00 174 992.62 0.00 380.00 0.00 165 992.62 0.00 400.00 0.00 157 992.62 0.00 420.00 0.00 150 992.62 0.00 440.00 0.00 143 992.62 0.00 460.00 0.00 137 992.62 0.00 480.00 0.00 131 992.62 0.00 500.00 0.00 126 992.62 0.00 520.00 0.00 122 992.62 0.00 540.00 0.00 118 992.61 0.00 560.00 0.00 114 992.61 0.00 580.00 0.00 110 992.61 0.00 600.00 0.00 106 992.61 0.00 MSE 24-hr 3 2-Year Rainfall=2.87"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 11HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond 1P: EXISTING POND Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 992.61 24,173 0 992.71 24,674 2,442 992.81 25,176 4,935 992.91 25,677 7,478 993.01 26,178 10,070 993.11 26,680 12,713 993.21 27,181 15,406 993.31 27,683 18,149 993.41 28,184 20,943 993.51 28,685 23,786 993.61 29,187 26,680 993.71 29,688 29,624 993.81 30,189 32,617 993.91 30,691 35,661 994.01 31,284 38,756 994.11 32,705 41,956 994.21 34,127 45,297 994.31 35,548 48,781 994.41 36,970 52,407 994.51 38,391 56,175 994.61 39,812 60,085 994.71 41,234 64,137 994.81 42,655 68,332 994.91 44,076 72,668 995.01 45,498 77,147 995.11 46,919 81,768 995.21 48,340 86,531 995.31 49,762 91,436 995.41 51,183 96,483 995.51 52,604 101,672 995.61 54,026 107,004 995.71 55,447 112,478 995.81 56,868 118,093 995.91 58,290 123,851 996.01 59,715 129,751 996.11 61,178 135,796 996.21 62,641 141,987 996.31 64,104 148,324 996.41 65,568 154,808 996.51 67,031 161,438 996.61 68,494 168,214 996.71 69,957 175,137 996.81 71,420 182,205 996.91 72,883 189,420 997.01 74,346 196,782 997.11 75,809 204,290 997.21 77,272 211,944 997.31 78,735 219,744 997.41 80,198 227,691 997.51 81,661 235,784 997.61 83,124 244,023 997.71 84,587 252,408 Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 997.81 86,050 260,940 997.91 87,513 269,618 MSE 24-hr 3 2-Year Rainfall=2.87"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 12HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Summary for Pond 2P: West Ditch [44] Hint: Outlet device #1 is below defined storage Inflow Area = 3.022 ac, 9.18% Impervious, Inflow Depth = 1.25" for 2-Year event Inflow = 5.80 cfs @ 12.17 hrs, Volume= 0.314 af Outflow = 5.80 cfs @ 12.17 hrs, Volume= 0.314 af, Atten= 0%, Lag= 0.2 min Primary = 5.80 cfs @ 12.17 hrs, Volume= 0.314 af Routed to Pond 10P : West Exisitng Wetland Secondary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af Routed to Pond 10P : West Exisitng Wetland Routing by Dyn-Stor-Ind method, Time Span= 0.00-600.00 hrs, dt= 0.01 hrs Peak Elev= 995.91' @ 12.17 hrs Surf.Area= 54 sf Storage= 27 cf Plug-Flow detention time= (not calculated: outflow precedes inflow) Center-of-Mass det. time= 0.0 min ( 810.3 - 810.2 ) Volume Invert Avail.Storage Storage Description #1 995.00' 5,727 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 995.00 5 0 0 996.00 59 32 32 997.00 825 442 474 998.00 2,243 1,534 2,008 998.60 4,093 1,901 3,909 999.00 5,000 1,819 5,727 Device Routing Invert Outlet Devices #1 Primary 994.57'18.0" Round CMP_Round 18" L= 57.1' CMP, mitered to conform to fill, Ke= 0.700 Inlet / Outlet Invert= 994.57' / 989.52' S= 0.0884 '/' Cc= 0.900 n= 0.025 Corrugated metal, Flow Area= 1.77 sf #2 Secondary 998.59'20.0' long x 16.0' breadth Existing Berm Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63 Primary OutFlow Max=5.80 cfs @ 12.17 hrs HW=995.91' TW=974.23' (Dynamic Tailwater) 1=CMP_Round 18" (Inlet Controls 5.80 cfs @ 3.48 fps) Secondary OutFlow Max=0.00 cfs @ 0.00 hrs HW=995.00' TW=974.10' (Dynamic Tailwater) 2=Existing Berm ( Controls 0.00 cfs) MSE 24-hr 3 2-Year Rainfall=2.87"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 13HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Pond 2P: West Ditch Inflow Outflow Primary Secondary Hydrograph Time (hours) 600550500450400350300250200150100500Flow (cfs)6 5 4 3 2 1 0 Inflow Area=3.022 ac Peak Elev=995.91' Storage=27 cf 5.80 cfs 5.80 cfs 5.80 cfs 0.00 cfs MSE 24-hr 3 2-Year Rainfall=2.87"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 14HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 2P: West Ditch Time (hours) Inflow (cfs) Storage (cubic-feet) Elevation (feet) Outflow (cfs) Primary (cfs) Secondary (cfs) 0.00 0.00 0 995.00 0.00 0.00 0.00 20.00 0.07 0 995.00 0.07 0.07 0.00 40.00 0.00 0 995.00 0.00 0.00 0.00 60.00 0.00 0 995.00 0.00 0.00 0.00 80.00 0.00 0 995.00 0.00 0.00 0.00 100.00 0.00 0 995.00 0.00 0.00 0.00 120.00 0.00 0 995.00 0.00 0.00 0.00 140.00 0.00 0 995.00 0.00 0.00 0.00 160.00 0.00 0 995.00 0.00 0.00 0.00 180.00 0.00 0 995.00 0.00 0.00 0.00 200.00 0.00 0 995.00 0.00 0.00 0.00 220.00 0.00 0 995.00 0.00 0.00 0.00 240.00 0.00 0 995.00 0.00 0.00 0.00 260.00 0.00 0 995.00 0.00 0.00 0.00 280.00 0.00 0 995.00 0.00 0.00 0.00 300.00 0.00 0 995.00 0.00 0.00 0.00 320.00 0.00 0 995.00 0.00 0.00 0.00 340.00 0.00 0 995.00 0.00 0.00 0.00 360.00 0.00 0 995.00 0.00 0.00 0.00 380.00 0.00 0 995.00 0.00 0.00 0.00 400.00 0.00 0 995.00 0.00 0.00 0.00 420.00 0.00 0 995.00 0.00 0.00 0.00 440.00 0.00 0 995.00 0.00 0.00 0.00 460.00 0.00 0 995.00 0.00 0.00 0.00 480.00 0.00 0 995.00 0.00 0.00 0.00 500.00 0.00 0 995.00 0.00 0.00 0.00 520.00 0.00 0 995.00 0.00 0.00 0.00 540.00 0.00 0 995.00 0.00 0.00 0.00 560.00 0.00 0 995.00 0.00 0.00 0.00 580.00 0.00 0 995.00 0.00 0.00 0.00 600.00 0.00 0 995.00 0.00 0.00 0.00 MSE 24-hr 3 2-Year Rainfall=2.87"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 15HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond 2P: West Ditch Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 995.00 5 0 995.05 8 0 995.10 10 1 995.15 13 1 995.20 16 2 995.25 19 3 995.30 21 4 995.35 24 5 995.40 27 6 995.45 29 8 995.50 32 9 995.55 35 11 995.60 37 13 995.65 40 15 995.70 43 17 995.75 46 19 995.80 48 21 995.85 51 24 995.90 54 26 995.95 56 29 996.00 59 32 996.05 97 36 996.10 136 42 996.15 174 49 996.20 212 59 996.25 251 71 996.30 289 84 996.35 327 100 996.40 365 117 996.45 404 136 996.50 442 157 996.55 480 180 996.60 519 205 996.65 557 232 996.70 595 261 996.75 634 292 996.80 672 324 996.85 710 359 996.90 748 395 996.95 787 434 997.00 825 474 997.05 896 517 997.10 967 564 997.15 1,038 614 997.20 1,109 667 997.25 1,180 725 997.30 1,250 785 997.35 1,321 850 997.40 1,392 917 997.45 1,463 989 997.50 1,534 1,064 997.55 1,605 1,142 Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 997.60 1,676 1,224 997.65 1,747 1,310 997.70 1,818 1,399 997.75 1,889 1,492 997.80 1,959 1,588 997.85 2,030 1,688 997.90 2,101 1,791 997.95 2,172 1,898 998.00 2,243 2,008 998.05 2,397 2,124 998.10 2,551 2,248 998.15 2,705 2,379 998.20 2,860 2,518 998.25 3,014 2,665 998.30 3,168 2,820 998.35 3,322 2,982 998.40 3,476 3,152 998.45 3,631 3,330 998.50 3,785 3,515 998.55 3,939 3,708 998.60 4,093 3,909 998.65 4,206 4,116 998.70 4,320 4,329 998.75 4,433 4,548 998.80 4,546 4,773 998.85 4,660 5,003 998.90 4,773 5,239 998.95 4,887 5,480 999.00 5,000 5,727 MSE 24-hr 3 2-Year Rainfall=2.87"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 16HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Summary for Pond 10P: West Exisitng Wetland Inflow Area = 18.722 ac, 18.43% Impervious, Inflow Depth = 1.41" for 2-Year event Inflow = 8.54 cfs @ 12.16 hrs, Volume= 2.203 af Outflow = 1.92 cfs @ 13.61 hrs, Volume= 2.203 af, Atten= 78%, Lag= 87.3 min Primary = 1.92 cfs @ 13.61 hrs, Volume= 2.203 af Routed to Link 7L : TOTAL Routing by Dyn-Stor-Ind method, Time Span= 0.00-600.00 hrs, dt= 0.01 hrs Starting Elev= 974.10' Surf.Area= 54,326 sf Storage= 5,411 cf Peak Elev= 974.35' @ 13.61 hrs Surf.Area= 55,407 sf Storage= 19,094 cf (13,683 cf above start) Plug-Flow detention time= 373.2 min calculated for 2.079 af (94% of inflow) Center-of-Mass det. time= 169.0 min ( 1,429.3 - 1,260.3 ) Volume Invert Avail.Storage Storage Description #1 974.00' 487,616 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 974.00 53,893 0 0 975.00 58,226 56,060 56,060 976.00 62,886 60,556 116,616 977.00 67,093 64,990 181,605 978.00 71,582 69,338 250,943 979.00 76,083 73,833 324,775 980.00 81,311 78,697 403,472 981.00 86,977 84,144 487,616 Device Routing Invert Outlet Devices #1 Primary 974.10'18.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=1.92 cfs @ 13.61 hrs HW=974.35' TW=0.00' (Dynamic Tailwater) 1=Orifice/Grate (Weir Controls 1.92 cfs @ 1.63 fps) MSE 24-hr 3 2-Year Rainfall=2.87"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 17HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Pond 10P: West Exisitng Wetland Inflow Primary Hydrograph Time (hours) 600550500450400350300250200150100500Flow (cfs)9 8 7 6 5 4 3 2 1 0 Inflow Area=18.722 ac Peak Elev=974.35' Storage=19,094 cf 8.54 cfs 1.92 cfs MSE 24-hr 3 2-Year Rainfall=2.87"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 18HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 10P: West Exisitng Wetland Time (hours) Inflow (cfs) Storage (cubic-feet) Elevation (feet) Primary (cfs) 0.00 0.00 5,411 974.10 0.00 20.00 1.32 16,704 974.31 1.44 40.00 0.06 7,339 974.14 0.10 60.00 0.01 6,056 974.11 0.02 80.00 0.01 5,755 974.11 0.01 100.00 0.00 5,633 974.10 0.00 120.00 0.00 5,569 974.10 0.00 140.00 0.00 5,532 974.10 0.00 160.00 0.00 5,507 974.10 0.00 180.00 0.00 5,490 974.10 0.00 200.00 0.00 5,477 974.10 0.00 220.00 0.00 5,468 974.10 0.00 240.00 0.00 5,460 974.10 0.00 260.00 0.00 5,454 974.10 0.00 280.00 0.00 5,449 974.10 0.00 300.00 0.00 5,445 974.10 0.00 320.00 0.00 5,442 974.10 0.00 340.00 0.00 5,439 974.10 0.00 360.00 0.00 5,437 974.10 0.00 380.00 0.00 5,435 974.10 0.00 400.00 0.00 5,433 974.10 0.00 420.00 0.00 5,432 974.10 0.00 440.00 0.00 5,430 974.10 0.00 460.00 0.00 5,429 974.10 0.00 480.00 0.00 5,428 974.10 0.00 500.00 0.00 5,427 974.10 0.00 520.00 0.00 5,426 974.10 0.00 540.00 0.00 5,425 974.10 0.00 560.00 0.00 5,425 974.10 0.00 580.00 0.00 5,424 974.10 0.00 600.00 0.00 5,423 974.10 0.00 MSE 24-hr 3 2-Year Rainfall=2.87"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 19HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond 10P: West Exisitng Wetland Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 974.00 53,893 0 974.10 54,326 5,411 974.20 54,760 10,865 974.30 55,193 16,363 974.40 55,626 21,904 974.50 56,060 27,488 974.60 56,493 33,116 974.70 56,926 38,787 974.80 57,359 44,501 974.90 57,793 50,259 975.00 58,226 56,060 975.10 58,692 61,905 975.20 59,158 67,798 975.30 59,624 73,737 975.40 60,090 79,723 975.50 60,556 85,755 975.60 61,022 91,834 975.70 61,488 97,959 975.80 61,954 104,131 975.90 62,420 110,350 976.00 62,886 116,616 976.10 63,307 122,925 976.20 63,727 129,277 976.30 64,148 135,671 976.40 64,569 142,106 976.50 64,990 148,584 976.60 65,410 155,104 976.70 65,831 161,666 976.80 66,252 168,271 976.90 66,672 174,917 977.00 67,093 181,605 977.10 67,542 188,337 977.20 67,991 195,113 977.30 68,440 201,935 977.40 68,889 208,801 977.50 69,338 215,713 977.60 69,786 222,669 977.70 70,235 229,670 977.80 70,684 236,716 977.90 71,133 243,807 978.00 71,582 250,943 978.10 72,032 258,123 978.20 72,482 265,349 978.30 72,932 272,620 978.40 73,382 279,935 978.50 73,833 287,296 978.60 74,283 294,702 978.70 74,733 302,153 978.80 75,183 309,648 978.90 75,633 317,189 979.00 76,083 324,775 979.10 76,606 332,409 Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 979.20 77,129 340,096 979.30 77,651 347,835 979.40 78,174 355,626 979.50 78,697 363,470 979.60 79,220 371,366 979.70 79,743 379,314 979.80 80,265 387,314 979.90 80,788 395,367 980.00 81,311 403,472 980.10 81,878 411,631 980.20 82,444 419,848 980.30 83,011 428,120 980.40 83,577 436,450 980.50 84,144 444,836 980.60 84,711 453,278 980.70 85,277 461,778 980.80 85,844 470,334 980.90 86,410 478,947 981.00 86,977 487,616 MSE 24-hr 3 10-Year Rainfall=4.26"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 20HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Time span=0.00-600.00 hrs, dt=0.01 hrs, 60001 points Runoff by SCS TR-20 method, UH=SCS, Weighted-Q Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Peak Elev=995.44' Storage=98,015 cf Inflow=59.39 cfs 3.212 afPond 1P: EXISTING POND 8.0" Round Culvert n=0.010 L=324.0' S=0.0080 '/' Outflow=1.75 cfs 3.210 af Peak Elev=997.09' Storage=551 cf Inflow=11.09 cfs 0.595 afPond 2P: West Ditch Primary=9.98 cfs 0.595 af Secondary=0.00 cfs 0.000 af Outflow=9.98 cfs 0.595 af Peak Elev=974.48' Storage=26,243 cf Inflow=13.92 cfs 3.999 afPond 10P: West Exisitng Wetland Outflow=3.58 cfs 3.999 af MSE 24-hr 3 10-Year Rainfall=4.26"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 21HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Summary for Pond 1P: EXISTING POND Inflow Area = 14.909 ac, 19.70% Impervious, Inflow Depth = 2.59" for 10-Year event Inflow = 59.39 cfs @ 12.14 hrs, Volume= 3.212 af Outflow = 1.75 cfs @ 15.03 hrs, Volume= 3.210 af, Atten= 97%, Lag= 173.4 min Primary = 1.75 cfs @ 15.03 hrs, Volume= 3.210 af Routed to Pond 10P : West Exisitng Wetland Routing by Dyn-Stor-Ind method, Time Span= 0.00-600.00 hrs, dt= 0.01 hrs Peak Elev= 995.44' @ 15.03 hrs Surf.Area= 51,607 sf Storage= 98,015 cf Plug-Flow detention time= 727.3 min calculated for 3.210 af (100% of inflow) Center-of-Mass det. time= 727.4 min ( 1,516.9 - 789.5 ) Volume Invert Avail.Storage Storage Description #1 992.61' 277,554 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 992.61 24,173 0 0 994.00 31,142 38,444 38,444 996.00 59,569 90,711 129,155 998.00 88,830 148,399 277,554 Device Routing Invert Outlet Devices #1 Primary 992.61'8.0" Round Culvert L= 324.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 992.61' / 990.02' S= 0.0080 '/' Cc= 0.900 n= 0.010 PVC, smooth interior, Flow Area= 0.35 sf Primary OutFlow Max=1.75 cfs @ 15.03 hrs HW=995.44' TW=974.40' (Dynamic Tailwater) 1=Culvert (Barrel Controls 1.75 cfs @ 5.00 fps) MSE 24-hr 3 10-Year Rainfall=4.26"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 22HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Pond 1P: EXISTING POND Inflow Primary Hydrograph Time (hours) 600550500450400350300250200150100500Flow (cfs)65 60 55 50 45 40 35 30 25 20 15 10 5 0 Inflow Area=14.909 ac Peak Elev=995.44' Storage=98,015 cf 8.0" Round Culvert n=0.010 L=324.0' S=0.0080 '/' 59.39 cfs 1.75 cfs MSE 24-hr 3 10-Year Rainfall=4.26"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 23HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 1P: EXISTING POND Time (hours) Inflow (cfs) Storage (cubic-feet) Elevation (feet) Primary (cfs) 0.00 0.00 0 992.61 0.00 20.00 0.59 82,759 995.13 1.69 40.00 0.00 7,721 992.92 0.24 60.00 0.00 2,212 992.70 0.02 80.00 0.00 1,255 992.66 0.01 100.00 0.00 872 992.65 0.00 120.00 0.00 667 992.64 0.00 140.00 0.00 539 992.63 0.00 160.00 0.00 452 992.63 0.00 180.00 0.00 390 992.63 0.00 200.00 0.00 342 992.62 0.00 220.00 0.00 305 992.62 0.00 240.00 0.00 276 992.62 0.00 260.00 0.00 253 992.62 0.00 280.00 0.00 233 992.62 0.00 300.00 0.00 216 992.62 0.00 320.00 0.00 202 992.62 0.00 340.00 0.00 190 992.62 0.00 360.00 0.00 179 992.62 0.00 380.00 0.00 169 992.62 0.00 400.00 0.00 161 992.62 0.00 420.00 0.00 153 992.62 0.00 440.00 0.00 146 992.62 0.00 460.00 0.00 140 992.62 0.00 480.00 0.00 134 992.62 0.00 500.00 0.00 129 992.62 0.00 520.00 0.00 124 992.62 0.00 540.00 0.00 119 992.61 0.00 560.00 0.00 115 992.61 0.00 580.00 0.00 112 992.61 0.00 600.00 0.00 108 992.61 0.00 MSE 24-hr 3 10-Year Rainfall=4.26"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 24HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond 1P: EXISTING POND Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 992.61 24,173 0 992.71 24,674 2,442 992.81 25,176 4,935 992.91 25,677 7,478 993.01 26,178 10,070 993.11 26,680 12,713 993.21 27,181 15,406 993.31 27,683 18,149 993.41 28,184 20,943 993.51 28,685 23,786 993.61 29,187 26,680 993.71 29,688 29,624 993.81 30,189 32,617 993.91 30,691 35,661 994.01 31,284 38,756 994.11 32,705 41,956 994.21 34,127 45,297 994.31 35,548 48,781 994.41 36,970 52,407 994.51 38,391 56,175 994.61 39,812 60,085 994.71 41,234 64,137 994.81 42,655 68,332 994.91 44,076 72,668 995.01 45,498 77,147 995.11 46,919 81,768 995.21 48,340 86,531 995.31 49,762 91,436 995.41 51,183 96,483 995.51 52,604 101,672 995.61 54,026 107,004 995.71 55,447 112,478 995.81 56,868 118,093 995.91 58,290 123,851 996.01 59,715 129,751 996.11 61,178 135,796 996.21 62,641 141,987 996.31 64,104 148,324 996.41 65,568 154,808 996.51 67,031 161,438 996.61 68,494 168,214 996.71 69,957 175,137 996.81 71,420 182,205 996.91 72,883 189,420 997.01 74,346 196,782 997.11 75,809 204,290 997.21 77,272 211,944 997.31 78,735 219,744 997.41 80,198 227,691 997.51 81,661 235,784 997.61 83,124 244,023 997.71 84,587 252,408 Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 997.81 86,050 260,940 997.91 87,513 269,618 MSE 24-hr 3 10-Year Rainfall=4.26"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 25HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Summary for Pond 2P: West Ditch [44] Hint: Outlet device #1 is below defined storage Inflow Area = 3.022 ac, 9.18% Impervious, Inflow Depth = 2.36" for 10-Year event Inflow = 11.09 cfs @ 12.16 hrs, Volume= 0.595 af Outflow = 9.98 cfs @ 12.20 hrs, Volume= 0.595 af, Atten= 10%, Lag= 2.4 min Primary = 9.98 cfs @ 12.20 hrs, Volume= 0.595 af Routed to Pond 10P : West Exisitng Wetland Secondary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af Routed to Pond 10P : West Exisitng Wetland Routing by Dyn-Stor-Ind method, Time Span= 0.00-600.00 hrs, dt= 0.01 hrs Peak Elev= 997.09' @ 12.20 hrs Surf.Area= 948 sf Storage= 551 cf Plug-Flow detention time= (not calculated: outflow precedes inflow) Center-of-Mass det. time= 0.2 min ( 799.9 - 799.7 ) Volume Invert Avail.Storage Storage Description #1 995.00' 5,727 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 995.00 5 0 0 996.00 59 32 32 997.00 825 442 474 998.00 2,243 1,534 2,008 998.60 4,093 1,901 3,909 999.00 5,000 1,819 5,727 Device Routing Invert Outlet Devices #1 Primary 994.57'18.0" Round CMP_Round 18" L= 57.1' CMP, mitered to conform to fill, Ke= 0.700 Inlet / Outlet Invert= 994.57' / 989.52' S= 0.0884 '/' Cc= 0.900 n= 0.025 Corrugated metal, Flow Area= 1.77 sf #2 Secondary 998.59'20.0' long x 16.0' breadth Existing Berm Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63 Primary OutFlow Max=9.97 cfs @ 12.20 hrs HW=997.08' TW=974.38' (Dynamic Tailwater) 1=CMP_Round 18" (Inlet Controls 9.97 cfs @ 5.64 fps) Secondary OutFlow Max=0.00 cfs @ 0.00 hrs HW=995.00' TW=974.10' (Dynamic Tailwater) 2=Existing Berm ( Controls 0.00 cfs) MSE 24-hr 3 10-Year Rainfall=4.26"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 26HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Pond 2P: West Ditch Inflow Outflow Primary Secondary Hydrograph Time (hours) 600550500450400350300250200150100500Flow (cfs)12 11 10 9 8 7 6 5 4 3 2 1 0 Inflow Area=3.022 ac Peak Elev=997.09' Storage=551 cf 11.09 cfs 9.98 cfs 9.98 cfs 0.00 cfs MSE 24-hr 3 10-Year Rainfall=4.26"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 27HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 2P: West Ditch Time (hours) Inflow (cfs) Storage (cubic-feet) Elevation (feet) Outflow (cfs) Primary (cfs) Secondary (cfs) 0.00 0.00 0 995.00 0.00 0.00 0.00 20.00 0.12 0 995.00 0.12 0.12 0.00 40.00 0.00 0 995.00 0.00 0.00 0.00 60.00 0.00 0 995.00 0.00 0.00 0.00 80.00 0.00 0 995.00 0.00 0.00 0.00 100.00 0.00 0 995.00 0.00 0.00 0.00 120.00 0.00 0 995.00 0.00 0.00 0.00 140.00 0.00 0 995.00 0.00 0.00 0.00 160.00 0.00 0 995.00 0.00 0.00 0.00 180.00 0.00 0 995.00 0.00 0.00 0.00 200.00 0.00 0 995.00 0.00 0.00 0.00 220.00 0.00 0 995.00 0.00 0.00 0.00 240.00 0.00 0 995.00 0.00 0.00 0.00 260.00 0.00 0 995.00 0.00 0.00 0.00 280.00 0.00 0 995.00 0.00 0.00 0.00 300.00 0.00 0 995.00 0.00 0.00 0.00 320.00 0.00 0 995.00 0.00 0.00 0.00 340.00 0.00 0 995.00 0.00 0.00 0.00 360.00 0.00 0 995.00 0.00 0.00 0.00 380.00 0.00 0 995.00 0.00 0.00 0.00 400.00 0.00 0 995.00 0.00 0.00 0.00 420.00 0.00 0 995.00 0.00 0.00 0.00 440.00 0.00 0 995.00 0.00 0.00 0.00 460.00 0.00 0 995.00 0.00 0.00 0.00 480.00 0.00 0 995.00 0.00 0.00 0.00 500.00 0.00 0 995.00 0.00 0.00 0.00 520.00 0.00 0 995.00 0.00 0.00 0.00 540.00 0.00 0 995.00 0.00 0.00 0.00 560.00 0.00 0 995.00 0.00 0.00 0.00 580.00 0.00 0 995.00 0.00 0.00 0.00 600.00 0.00 0 995.00 0.00 0.00 0.00 MSE 24-hr 3 10-Year Rainfall=4.26"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 28HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond 2P: West Ditch Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 995.00 5 0 995.05 8 0 995.10 10 1 995.15 13 1 995.20 16 2 995.25 19 3 995.30 21 4 995.35 24 5 995.40 27 6 995.45 29 8 995.50 32 9 995.55 35 11 995.60 37 13 995.65 40 15 995.70 43 17 995.75 46 19 995.80 48 21 995.85 51 24 995.90 54 26 995.95 56 29 996.00 59 32 996.05 97 36 996.10 136 42 996.15 174 49 996.20 212 59 996.25 251 71 996.30 289 84 996.35 327 100 996.40 365 117 996.45 404 136 996.50 442 157 996.55 480 180 996.60 519 205 996.65 557 232 996.70 595 261 996.75 634 292 996.80 672 324 996.85 710 359 996.90 748 395 996.95 787 434 997.00 825 474 997.05 896 517 997.10 967 564 997.15 1,038 614 997.20 1,109 667 997.25 1,180 725 997.30 1,250 785 997.35 1,321 850 997.40 1,392 917 997.45 1,463 989 997.50 1,534 1,064 997.55 1,605 1,142 Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 997.60 1,676 1,224 997.65 1,747 1,310 997.70 1,818 1,399 997.75 1,889 1,492 997.80 1,959 1,588 997.85 2,030 1,688 997.90 2,101 1,791 997.95 2,172 1,898 998.00 2,243 2,008 998.05 2,397 2,124 998.10 2,551 2,248 998.15 2,705 2,379 998.20 2,860 2,518 998.25 3,014 2,665 998.30 3,168 2,820 998.35 3,322 2,982 998.40 3,476 3,152 998.45 3,631 3,330 998.50 3,785 3,515 998.55 3,939 3,708 998.60 4,093 3,909 998.65 4,206 4,116 998.70 4,320 4,329 998.75 4,433 4,548 998.80 4,546 4,773 998.85 4,660 5,003 998.90 4,773 5,239 998.95 4,887 5,480 999.00 5,000 5,727 MSE 24-hr 3 10-Year Rainfall=4.26"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 29HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Summary for Pond 10P: West Exisitng Wetland Inflow Area = 18.722 ac, 18.43% Impervious, Inflow Depth = 2.56" for 10-Year event Inflow = 13.92 cfs @ 12.17 hrs, Volume= 3.999 af Outflow = 3.58 cfs @ 12.66 hrs, Volume= 3.999 af, Atten= 74%, Lag= 29.6 min Primary = 3.58 cfs @ 12.66 hrs, Volume= 3.999 af Routed to Link 7L : TOTAL Routing by Dyn-Stor-Ind method, Time Span= 0.00-600.00 hrs, dt= 0.01 hrs Starting Elev= 974.10' Surf.Area= 54,326 sf Storage= 5,411 cf Peak Elev= 974.48' @ 12.66 hrs Surf.Area= 55,963 sf Storage= 26,243 cf (20,832 cf above start) Plug-Flow detention time= 270.0 min calculated for 3.875 af (97% of inflow) Center-of-Mass det. time= 143.5 min ( 1,517.7 - 1,374.2 ) Volume Invert Avail.Storage Storage Description #1 974.00' 487,616 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 974.00 53,893 0 0 975.00 58,226 56,060 56,060 976.00 62,886 60,556 116,616 977.00 67,093 64,990 181,605 978.00 71,582 69,338 250,943 979.00 76,083 73,833 324,775 980.00 81,311 78,697 403,472 981.00 86,977 84,144 487,616 Device Routing Invert Outlet Devices #1 Primary 974.10'18.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=3.58 cfs @ 12.66 hrs HW=974.48' TW=0.00' (Dynamic Tailwater) 1=Orifice/Grate (Weir Controls 3.58 cfs @ 2.01 fps) MSE 24-hr 3 10-Year Rainfall=4.26"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 30HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Pond 10P: West Exisitng Wetland Inflow Primary Hydrograph Time (hours) 600550500450400350300250200150100500Flow (cfs)15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Inflow Area=18.722 ac Peak Elev=974.48' Storage=26,243 cf 13.92 cfs 3.58 cfs MSE 24-hr 3 10-Year Rainfall=4.26"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 31HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 10P: West Exisitng Wetland Time (hours) Inflow (cfs) Storage (cubic-feet) Elevation (feet) Primary (cfs) 0.00 0.00 5,411 974.10 0.00 20.00 1.84 19,009 974.35 1.90 40.00 0.24 10,075 974.19 0.39 60.00 0.02 6,385 974.12 0.04 80.00 0.01 5,855 974.11 0.01 100.00 0.00 5,678 974.10 0.01 120.00 0.00 5,594 974.10 0.00 140.00 0.00 5,547 974.10 0.00 160.00 0.00 5,517 974.10 0.00 180.00 0.00 5,497 974.10 0.00 200.00 0.00 5,483 974.10 0.00 220.00 0.00 5,472 974.10 0.00 240.00 0.00 5,463 974.10 0.00 260.00 0.00 5,457 974.10 0.00 280.00 0.00 5,451 974.10 0.00 300.00 0.00 5,447 974.10 0.00 320.00 0.00 5,444 974.10 0.00 340.00 0.00 5,441 974.10 0.00 360.00 0.00 5,438 974.10 0.00 380.00 0.00 5,436 974.10 0.00 400.00 0.00 5,434 974.10 0.00 420.00 0.00 5,432 974.10 0.00 440.00 0.00 5,431 974.10 0.00 460.00 0.00 5,430 974.10 0.00 480.00 0.00 5,428 974.10 0.00 500.00 0.00 5,427 974.10 0.00 520.00 0.00 5,426 974.10 0.00 540.00 0.00 5,426 974.10 0.00 560.00 0.00 5,425 974.10 0.00 580.00 0.00 5,424 974.10 0.00 600.00 0.00 5,424 974.10 0.00 MSE 24-hr 3 10-Year Rainfall=4.26"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 32HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond 10P: West Exisitng Wetland Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 974.00 53,893 0 974.10 54,326 5,411 974.20 54,760 10,865 974.30 55,193 16,363 974.40 55,626 21,904 974.50 56,060 27,488 974.60 56,493 33,116 974.70 56,926 38,787 974.80 57,359 44,501 974.90 57,793 50,259 975.00 58,226 56,060 975.10 58,692 61,905 975.20 59,158 67,798 975.30 59,624 73,737 975.40 60,090 79,723 975.50 60,556 85,755 975.60 61,022 91,834 975.70 61,488 97,959 975.80 61,954 104,131 975.90 62,420 110,350 976.00 62,886 116,616 976.10 63,307 122,925 976.20 63,727 129,277 976.30 64,148 135,671 976.40 64,569 142,106 976.50 64,990 148,584 976.60 65,410 155,104 976.70 65,831 161,666 976.80 66,252 168,271 976.90 66,672 174,917 977.00 67,093 181,605 977.10 67,542 188,337 977.20 67,991 195,113 977.30 68,440 201,935 977.40 68,889 208,801 977.50 69,338 215,713 977.60 69,786 222,669 977.70 70,235 229,670 977.80 70,684 236,716 977.90 71,133 243,807 978.00 71,582 250,943 978.10 72,032 258,123 978.20 72,482 265,349 978.30 72,932 272,620 978.40 73,382 279,935 978.50 73,833 287,296 978.60 74,283 294,702 978.70 74,733 302,153 978.80 75,183 309,648 978.90 75,633 317,189 979.00 76,083 324,775 979.10 76,606 332,409 Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 979.20 77,129 340,096 979.30 77,651 347,835 979.40 78,174 355,626 979.50 78,697 363,470 979.60 79,220 371,366 979.70 79,743 379,314 979.80 80,265 387,314 979.90 80,788 395,367 980.00 81,311 403,472 980.10 81,878 411,631 980.20 82,444 419,848 980.30 83,011 428,120 980.40 83,577 436,450 980.50 84,144 444,836 980.60 84,711 453,278 980.70 85,277 461,778 980.80 85,844 470,334 980.90 86,410 478,947 981.00 86,977 487,616 MSE 24-hr 3 100-Year Rainfall=7.38"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 33HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Time span=0.00-600.00 hrs, dt=0.01 hrs, 60001 points Runoff by SCS TR-20 method, UH=SCS, Weighted-Q Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Peak Elev=997.38' Storage=225,013 cf Inflow=122.92 cfs 6.746 afPond 1P: EXISTING POND 8.0" Round Culvert n=0.010 L=324.0' S=0.0080 '/' Outflow=2.07 cfs 6.744 af Peak Elev=998.80' Storage=4,751 cf Inflow=23.82 cfs 1.299 afPond 2P: West Ditch Primary=14.00 cfs 1.265 af Secondary=4.98 cfs 0.035 af Outflow=18.98 cfs 1.299 af Peak Elev=974.85' Storage=47,120 cf Inflow=24.06 cfs 8.431 afPond 10P: West Exisitng Wetland Outflow=7.35 cfs 8.431 af MSE 24-hr 3 100-Year Rainfall=7.38"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 34HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Summary for Pond 1P: EXISTING POND Inflow Area = 14.909 ac, 19.70% Impervious, Inflow Depth = 5.43" for 100-Year event Inflow = 122.92 cfs @ 12.14 hrs, Volume= 6.746 af Outflow = 2.07 cfs @ 15.37 hrs, Volume= 6.744 af, Atten= 98%, Lag= 193.7 min Primary = 2.07 cfs @ 15.37 hrs, Volume= 6.744 af Routed to Pond 10P : West Exisitng Wetland Routing by Dyn-Stor-Ind method, Time Span= 0.00-600.00 hrs, dt= 0.01 hrs Peak Elev= 997.38' @ 15.37 hrs Surf.Area= 79,708 sf Storage= 225,013 cf Plug-Flow detention time= 1,197.0 min calculated for 6.744 af (100% of inflow) Center-of-Mass det. time= 1,197.3 min ( 1,975.8 - 778.5 ) Volume Invert Avail.Storage Storage Description #1 992.61' 277,554 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 992.61 24,173 0 0 994.00 31,142 38,444 38,444 996.00 59,569 90,711 129,155 998.00 88,830 148,399 277,554 Device Routing Invert Outlet Devices #1 Primary 992.61'8.0" Round Culvert L= 324.0' CPP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 992.61' / 990.02' S= 0.0080 '/' Cc= 0.900 n= 0.010 PVC, smooth interior, Flow Area= 0.35 sf Primary OutFlow Max=2.07 cfs @ 15.37 hrs HW=997.38' TW=974.48' (Dynamic Tailwater) 1=Culvert (Barrel Controls 2.07 cfs @ 5.93 fps) MSE 24-hr 3 100-Year Rainfall=7.38"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 35HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Pond 1P: EXISTING POND Inflow Primary Hydrograph Time (hours) 600550500450400350300250200150100500Flow (cfs)130 120 110 100 90 80 70 60 50 40 30 20 10 0 Inflow Area=14.909 ac Peak Elev=997.38' Storage=225,013 cf 8.0" Round Culvert n=0.010 L=324.0' S=0.0080 '/' 122.92 cfs 2.07 cfs MSE 24-hr 3 100-Year Rainfall=7.38"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 36HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 1P: EXISTING POND Time (hours) Inflow (cfs) Storage (cubic-feet) Elevation (feet) Primary (cfs) 0.00 0.00 0 992.61 0.00 20.00 1.11 216,993 997.27 2.06 40.00 0.00 89,859 995.28 1.72 60.00 0.00 7,931 992.93 0.25 80.00 0.00 2,232 992.70 0.02 100.00 0.00 1,262 992.66 0.01 120.00 0.00 875 992.65 0.00 140.00 0.00 669 992.64 0.00 160.00 0.00 540 992.63 0.00 180.00 0.00 453 992.63 0.00 200.00 0.00 390 992.63 0.00 220.00 0.00 343 992.62 0.00 240.00 0.00 306 992.62 0.00 260.00 0.00 277 992.62 0.00 280.00 0.00 253 992.62 0.00 300.00 0.00 233 992.62 0.00 320.00 0.00 216 992.62 0.00 340.00 0.00 202 992.62 0.00 360.00 0.00 190 992.62 0.00 380.00 0.00 179 992.62 0.00 400.00 0.00 169 992.62 0.00 420.00 0.00 161 992.62 0.00 440.00 0.00 153 992.62 0.00 460.00 0.00 146 992.62 0.00 480.00 0.00 140 992.62 0.00 500.00 0.00 134 992.62 0.00 520.00 0.00 129 992.62 0.00 540.00 0.00 124 992.62 0.00 560.00 0.00 119 992.61 0.00 580.00 0.00 115 992.61 0.00 600.00 0.00 112 992.61 0.00 MSE 24-hr 3 100-Year Rainfall=7.38"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 37HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond 1P: EXISTING POND Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 992.61 24,173 0 992.71 24,674 2,442 992.81 25,176 4,935 992.91 25,677 7,478 993.01 26,178 10,070 993.11 26,680 12,713 993.21 27,181 15,406 993.31 27,683 18,149 993.41 28,184 20,943 993.51 28,685 23,786 993.61 29,187 26,680 993.71 29,688 29,624 993.81 30,189 32,617 993.91 30,691 35,661 994.01 31,284 38,756 994.11 32,705 41,956 994.21 34,127 45,297 994.31 35,548 48,781 994.41 36,970 52,407 994.51 38,391 56,175 994.61 39,812 60,085 994.71 41,234 64,137 994.81 42,655 68,332 994.91 44,076 72,668 995.01 45,498 77,147 995.11 46,919 81,768 995.21 48,340 86,531 995.31 49,762 91,436 995.41 51,183 96,483 995.51 52,604 101,672 995.61 54,026 107,004 995.71 55,447 112,478 995.81 56,868 118,093 995.91 58,290 123,851 996.01 59,715 129,751 996.11 61,178 135,796 996.21 62,641 141,987 996.31 64,104 148,324 996.41 65,568 154,808 996.51 67,031 161,438 996.61 68,494 168,214 996.71 69,957 175,137 996.81 71,420 182,205 996.91 72,883 189,420 997.01 74,346 196,782 997.11 75,809 204,290 997.21 77,272 211,944 997.31 78,735 219,744 997.41 80,198 227,691 997.51 81,661 235,784 997.61 83,124 244,023 997.71 84,587 252,408 Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 997.81 86,050 260,940 997.91 87,513 269,618 MSE 24-hr 3 100-Year Rainfall=7.38"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 38HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Summary for Pond 2P: West Ditch [44] Hint: Outlet device #1 is below defined storage Inflow Area = 3.022 ac, 9.18% Impervious, Inflow Depth = 5.16" for 100-Year event Inflow = 23.82 cfs @ 12.16 hrs, Volume= 1.299 af Outflow = 18.98 cfs @ 12.22 hrs, Volume= 1.299 af, Atten= 20%, Lag= 3.7 min Primary = 14.00 cfs @ 12.22 hrs, Volume= 1.265 af Routed to Pond 10P : West Exisitng Wetland Secondary = 4.98 cfs @ 12.22 hrs, Volume= 0.035 af Routed to Pond 10P : West Exisitng Wetland Routing by Dyn-Stor-Ind method, Time Span= 0.00-600.00 hrs, dt= 0.01 hrs Peak Elev= 998.80' @ 12.22 hrs Surf.Area= 4,536 sf Storage= 4,751 cf Plug-Flow detention time= (not calculated: outflow precedes inflow) Center-of-Mass det. time= 1.4 min ( 787.7 - 786.3 ) Volume Invert Avail.Storage Storage Description #1 995.00' 5,727 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 995.00 5 0 0 996.00 59 32 32 997.00 825 442 474 998.00 2,243 1,534 2,008 998.60 4,093 1,901 3,909 999.00 5,000 1,819 5,727 Device Routing Invert Outlet Devices #1 Primary 994.57'18.0" Round CMP_Round 18" L= 57.1' CMP, mitered to conform to fill, Ke= 0.700 Inlet / Outlet Invert= 994.57' / 989.52' S= 0.0884 '/' Cc= 0.900 n= 0.025 Corrugated metal, Flow Area= 1.77 sf #2 Secondary 998.59'20.0' long x 16.0' breadth Existing Berm Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63 Primary OutFlow Max=13.99 cfs @ 12.22 hrs HW=998.79' TW=974.65' (Dynamic Tailwater) 1=CMP_Round 18" (Inlet Controls 13.99 cfs @ 7.92 fps) Secondary OutFlow Max=4.94 cfs @ 12.22 hrs HW=998.79' TW=974.65' (Dynamic Tailwater) 2=Existing Berm (Weir Controls 4.94 cfs @ 1.21 fps) MSE 24-hr 3 100-Year Rainfall=7.38"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 39HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Pond 2P: West Ditch Inflow Outflow Primary Secondary Hydrograph Time (hours) 600550500450400350300250200150100500Flow (cfs)26 24 22 20 18 16 14 12 10 8 6 4 2 0 Inflow Area=3.022 ac Peak Elev=998.80' Storage=4,751 cf 23.82 cfs 18.98 cfs 14.00 cfs 4.98 cfs MSE 24-hr 3 100-Year Rainfall=7.38"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 40HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 2P: West Ditch Time (hours) Inflow (cfs) Storage (cubic-feet) Elevation (feet) Outflow (cfs) Primary (cfs) Secondary (cfs) 0.00 0.00 0 995.00 0.00 0.00 0.00 20.00 0.22 0 995.00 0.22 0.22 0.00 40.00 0.00 0 995.00 0.00 0.00 0.00 60.00 0.00 0 995.00 0.00 0.00 0.00 80.00 0.00 0 995.00 0.00 0.00 0.00 100.00 0.00 0 995.00 0.00 0.00 0.00 120.00 0.00 0 995.00 0.00 0.00 0.00 140.00 0.00 0 995.00 0.00 0.00 0.00 160.00 0.00 0 995.00 0.00 0.00 0.00 180.00 0.00 0 995.00 0.00 0.00 0.00 200.00 0.00 0 995.00 0.00 0.00 0.00 220.00 0.00 0 995.00 0.00 0.00 0.00 240.00 0.00 0 995.00 0.00 0.00 0.00 260.00 0.00 0 995.00 0.00 0.00 0.00 280.00 0.00 0 995.00 0.00 0.00 0.00 300.00 0.00 0 995.00 0.00 0.00 0.00 320.00 0.00 0 995.00 0.00 0.00 0.00 340.00 0.00 0 995.00 0.00 0.00 0.00 360.00 0.00 0 995.00 0.00 0.00 0.00 380.00 0.00 0 995.00 0.00 0.00 0.00 400.00 0.00 0 995.00 0.00 0.00 0.00 420.00 0.00 0 995.00 0.00 0.00 0.00 440.00 0.00 0 995.00 0.00 0.00 0.00 460.00 0.00 0 995.00 0.00 0.00 0.00 480.00 0.00 0 995.00 0.00 0.00 0.00 500.00 0.00 0 995.00 0.00 0.00 0.00 520.00 0.00 0 995.00 0.00 0.00 0.00 540.00 0.00 0 995.00 0.00 0.00 0.00 560.00 0.00 0 995.00 0.00 0.00 0.00 580.00 0.00 0 995.00 0.00 0.00 0.00 600.00 0.00 0 995.00 0.00 0.00 0.00 MSE 24-hr 3 100-Year Rainfall=7.38"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 41HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond 2P: West Ditch Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 995.00 5 0 995.05 8 0 995.10 10 1 995.15 13 1 995.20 16 2 995.25 19 3 995.30 21 4 995.35 24 5 995.40 27 6 995.45 29 8 995.50 32 9 995.55 35 11 995.60 37 13 995.65 40 15 995.70 43 17 995.75 46 19 995.80 48 21 995.85 51 24 995.90 54 26 995.95 56 29 996.00 59 32 996.05 97 36 996.10 136 42 996.15 174 49 996.20 212 59 996.25 251 71 996.30 289 84 996.35 327 100 996.40 365 117 996.45 404 136 996.50 442 157 996.55 480 180 996.60 519 205 996.65 557 232 996.70 595 261 996.75 634 292 996.80 672 324 996.85 710 359 996.90 748 395 996.95 787 434 997.00 825 474 997.05 896 517 997.10 967 564 997.15 1,038 614 997.20 1,109 667 997.25 1,180 725 997.30 1,250 785 997.35 1,321 850 997.40 1,392 917 997.45 1,463 989 997.50 1,534 1,064 997.55 1,605 1,142 Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 997.60 1,676 1,224 997.65 1,747 1,310 997.70 1,818 1,399 997.75 1,889 1,492 997.80 1,959 1,588 997.85 2,030 1,688 997.90 2,101 1,791 997.95 2,172 1,898 998.00 2,243 2,008 998.05 2,397 2,124 998.10 2,551 2,248 998.15 2,705 2,379 998.20 2,860 2,518 998.25 3,014 2,665 998.30 3,168 2,820 998.35 3,322 2,982 998.40 3,476 3,152 998.45 3,631 3,330 998.50 3,785 3,515 998.55 3,939 3,708 998.60 4,093 3,909 998.65 4,206 4,116 998.70 4,320 4,329 998.75 4,433 4,548 998.80 4,546 4,773 998.85 4,660 5,003 998.90 4,773 5,239 998.95 4,887 5,480 999.00 5,000 5,727 MSE 24-hr 3 100-Year Rainfall=7.38"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 42HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Summary for Pond 10P: West Exisitng Wetland Inflow Area = 18.722 ac, 18.43% Impervious, Inflow Depth = 5.40" for 100-Year event Inflow = 24.06 cfs @ 12.22 hrs, Volume= 8.431 af Outflow = 7.35 cfs @ 12.55 hrs, Volume= 8.431 af, Atten= 69%, Lag= 20.1 min Primary = 7.35 cfs @ 12.55 hrs, Volume= 8.431 af Routed to Link 7L : TOTAL Routing by Dyn-Stor-Ind method, Time Span= 0.00-600.00 hrs, dt= 0.01 hrs Starting Elev= 974.10' Surf.Area= 54,326 sf Storage= 5,411 cf Peak Elev= 974.85' @ 12.55 hrs Surf.Area= 57,557 sf Storage= 47,120 cf (41,709 cf above start) Plug-Flow detention time= 203.0 min calculated for 8.307 af (99% of inflow) Center-of-Mass det. time= 125.1 min ( 1,862.1 - 1,737.0 ) Volume Invert Avail.Storage Storage Description #1 974.00' 487,616 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 974.00 53,893 0 0 975.00 58,226 56,060 56,060 976.00 62,886 60,556 116,616 977.00 67,093 64,990 181,605 978.00 71,582 69,338 250,943 979.00 76,083 73,833 324,775 980.00 81,311 78,697 403,472 981.00 86,977 84,144 487,616 Device Routing Invert Outlet Devices #1 Primary 974.10'18.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=7.35 cfs @ 12.55 hrs HW=974.85' TW=0.00' (Dynamic Tailwater) 1=Orifice/Grate (Orifice Controls 7.35 cfs @ 4.16 fps) MSE 24-hr 3 100-Year Rainfall=7.38"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 43HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Pond 10P: West Exisitng Wetland Inflow Primary Hydrograph Time (hours) 600550500450400350300250200150100500Flow (cfs)26 24 22 20 18 16 14 12 10 8 6 4 2 0 Inflow Area=18.722 ac Peak Elev=974.85' Storage=47,120 cf 24.06 cfs 7.35 cfs MSE 24-hr 3 100-Year Rainfall=7.38"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 44HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 10P: West Exisitng Wetland Time (hours) Inflow (cfs) Storage (cubic-feet) Elevation (feet) Primary (cfs) 0.00 0.00 5,411 974.10 0.00 20.00 2.34 21,442 974.39 2.43 40.00 1.72 18,254 974.33 1.75 60.00 0.25 10,206 974.19 0.40 80.00 0.02 6,397 974.12 0.04 100.00 0.01 5,858 974.11 0.01 120.00 0.00 5,679 974.10 0.01 140.00 0.00 5,595 974.10 0.00 160.00 0.00 5,547 974.10 0.00 180.00 0.00 5,518 974.10 0.00 200.00 0.00 5,497 974.10 0.00 220.00 0.00 5,483 974.10 0.00 240.00 0.00 5,472 974.10 0.00 260.00 0.00 5,463 974.10 0.00 280.00 0.00 5,457 974.10 0.00 300.00 0.00 5,451 974.10 0.00 320.00 0.00 5,447 974.10 0.00 340.00 0.00 5,444 974.10 0.00 360.00 0.00 5,441 974.10 0.00 380.00 0.00 5,438 974.10 0.00 400.00 0.00 5,436 974.10 0.00 420.00 0.00 5,434 974.10 0.00 440.00 0.00 5,432 974.10 0.00 460.00 0.00 5,431 974.10 0.00 480.00 0.00 5,430 974.10 0.00 500.00 0.00 5,428 974.10 0.00 520.00 0.00 5,427 974.10 0.00 540.00 0.00 5,426 974.10 0.00 560.00 0.00 5,426 974.10 0.00 580.00 0.00 5,425 974.10 0.00 600.00 0.00 5,424 974.10 0.00 MSE 24-hr 3 100-Year Rainfall=7.38"EDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 45HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond 10P: West Exisitng Wetland Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 974.00 53,893 0 974.10 54,326 5,411 974.20 54,760 10,865 974.30 55,193 16,363 974.40 55,626 21,904 974.50 56,060 27,488 974.60 56,493 33,116 974.70 56,926 38,787 974.80 57,359 44,501 974.90 57,793 50,259 975.00 58,226 56,060 975.10 58,692 61,905 975.20 59,158 67,798 975.30 59,624 73,737 975.40 60,090 79,723 975.50 60,556 85,755 975.60 61,022 91,834 975.70 61,488 97,959 975.80 61,954 104,131 975.90 62,420 110,350 976.00 62,886 116,616 976.10 63,307 122,925 976.20 63,727 129,277 976.30 64,148 135,671 976.40 64,569 142,106 976.50 64,990 148,584 976.60 65,410 155,104 976.70 65,831 161,666 976.80 66,252 168,271 976.90 66,672 174,917 977.00 67,093 181,605 977.10 67,542 188,337 977.20 67,991 195,113 977.30 68,440 201,935 977.40 68,889 208,801 977.50 69,338 215,713 977.60 69,786 222,669 977.70 70,235 229,670 977.80 70,684 236,716 977.90 71,133 243,807 978.00 71,582 250,943 978.10 72,032 258,123 978.20 72,482 265,349 978.30 72,932 272,620 978.40 73,382 279,935 978.50 73,833 287,296 978.60 74,283 294,702 978.70 74,733 302,153 978.80 75,183 309,648 978.90 75,633 317,189 979.00 76,083 324,775 979.10 76,606 332,409 Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 979.20 77,129 340,096 979.30 77,651 347,835 979.40 78,174 355,626 979.50 78,697 363,470 979.60 79,220 371,366 979.70 79,743 379,314 979.80 80,265 387,314 979.90 80,788 395,367 980.00 81,311 403,472 980.10 81,878 411,631 980.20 82,444 419,848 980.30 83,011 428,120 980.40 83,577 436,450 980.50 84,144 444,836 980.60 84,711 453,278 980.70 85,277 461,778 980.80 85,844 470,334 980.90 86,410 478,947 981.00 86,977 487,616 123 7 5 1 2 3 4 5 67 8 9 10 11 12 13 6 BLOCK 2BLOCK 2BLOCK 1 BLOCK 1 1000' Shoreland District Boundary STORMWATER WETLAND/FILTRATION NWL:994.0 100 YEAR HWL:999.84 PEACEFUL LANEPEACEFUL LANE4 NEZ PERCE DRIVE PEACEFUL LANEFILTRATION BASIN 2 100 YEAR HWL:997.95 GU File Location: X:\4000320-00\001\40 Design\45 Stormwater\HYDRO-PRO.dwg Plotted By: Tyler Stricherz on April 18, 2025 at 9:02:26 AMKnow what's below. Call before you dig. R Dial 811 FOR R E VI E W O N L Y PRE LI MI N A R Y NOT F O R C O N S T R U C TI O N 0 SCALE IN FEET 35 70 140 N W S E PRELIMINARY PLAT CITY SUBMITTALFINAL PLAT - CITY SUBMITTAL 4-18-202512-19-2024 1 1 CHANHASSEN, MNPLEASANT VIEW POINTEPROPOSED DRAINAGE MAPwww.alliant-inc.com PROJECT TEAM DATA QA/QC CHECK DateBy CERTIFICATION Date License no.DATEDESCRIPTIONProject No.: Drafted By: Designed By: Sheet of TAS I hereby certify that this plan, specification, or report was prepared by me or under my direct supervision and that I am a duly Licensed Professional Engineer under the laws of the State of MN. 1 1 LEGEND OFF-1 OFF-1 OFF-2 OFF-2 OFF-3 OFF-3 OFF-4 OFF-4 OFF-5 OFF-5 OFF-6 OFF-6 OFF-7 OFF-7 OFF-8 OFF-8 OFF-9 OFF-9 S1 S1 S2 S2 S3 S3 S4 S4 S5 S5 S6 S6 S7 S7 S8 S8 1P FILTRATION/POND 8P West Filtration Basin 10P West Existing Wetland 3L SOUTH OVERLAND 6L EAST OVERLAND 7L TOTAL Routing Diagram for PDRN Prepared by Alliant Engineering, Inc, Printed 4/18/2025 HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Subcat Reach Pond Link PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 2HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Project Notes PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 3HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Rainfall Events Listing (selected events) Event# Event Name Storm Type Curve Mode Duration (hours) B/B Depth (inches) AMC 1 2-Year MSE 24-hr 3 Default 24.00 1 2.87 2 2 10-Year MSE 24-hr 3 Default 24.00 1 4.26 2 3 100-Year MSE 24-hr 3 Default 24.00 1 7.38 2 PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 4HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Area Listing (all nodes) Area (acres) CN Description (subcatchment-numbers) 8.561 80 >75% Grass cover, Good, HSG D (OFF-4, OFF-6, OFF-7, OFF-8, OFF-9, S1, S2, S3, S8) 0.040 98 Impervious, HSG D (OFF-6) 0.927 98 Paved parking, HSG C (OFF-3, OFF-4) 5.373 98 Paved parking, HSG D (OFF-1, OFF-8, OFF-9, S2) 0.092 98 Unconnected roofs, HSG C (OFF-2) 1.625 98 Unconnected roofs, HSG D (OFF-7, S1, S4, S5) 1.047 98 Water Surface, HSG D (S1) 0.498 82 Woods/grass comb., Fair, HSG D (OFF-5, S5) 5.759 79 Woods/grass comb., Good, HSG D (OFF-1, OFF-2, OFF-3, S4, S6) 0.214 86 Woods/grass comb., Poor, HSG D (S7) 24.134 87 TOTAL AREA PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 5HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Soil Listing (all nodes) Area (acres) Soil Group Subcatchment Numbers 0.000 HSG A 0.000 HSG B 1.019 HSG C OFF-2, OFF-3, OFF-4 23.115 HSG D OFF-1, OFF-2, OFF-3, OFF-4, OFF-5, OFF-6, OFF-7, OFF-8, OFF-9, S1, S2, S3, S4, S5, S6, S7, S8 0.000 Other 24.134 TOTAL AREA PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 6HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Ground Covers (all nodes) HSG-A (acres) HSG-B (acres) HSG-C (acres) HSG-D (acres) Other (acres) Total (acres) Ground Cover Subcatchment Numbers 0.000 0.000 0.000 8.561 0.000 8.561 >75% Grass cover, Good OFF-4, OFF-6, OFF-7, OFF-8, OFF-9, S1, S2, S3, S8 0.000 0.000 0.000 0.040 0.000 0.040 Impervious OFF-6 0.000 0.000 0.927 5.373 0.000 6.300 Paved parking OFF-1, OFF-3, OFF-4, OFF-8, OFF-9, S2 0.000 0.000 0.092 1.625 0.000 1.717 Unconnected roofs OFF-2, OFF-7, S1, S4, S5 0.000 0.000 0.000 1.047 0.000 1.047 Water Surface S1 0.000 0.000 0.000 0.498 0.000 0.498 Woods/grass comb., Fair OFF-5, S5 0.000 0.000 0.000 5.759 0.000 5.759 Woods/grass comb., Good OFF-1, OFF-2, OFF-3, S4, S6 0.000 0.000 0.000 0.214 0.000 0.214 Woods/grass comb., Poor S7 0.000 0.000 1.019 23.115 0.000 24.134 TOTAL AREA MSE 24-hr 3 2-Year Rainfall=2.87"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 7HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Time span=0.00-600.00 hrs, dt=0.01 hrs, 60001 points Runoff by SCS TR-20 method, UH=SCS, Weighted-Q Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Peak Elev=996.03' Storage=182,508 cf Inflow=46.18 cfs 3.019 afPond 1P: FILTRATION/POND Outflow=1.25 cfs 2.986 af Peak Elev=996.78' Storage=6,498 cf Inflow=7.72 cfs 0.354 afPond 8P: West Filtration Basin Outflow=3.34 cfs 0.354 af Peak Elev=974.30' Storage=16,578 cf Inflow=3.81 cfs 3.375 afPond 10P: West Existing Wetland Outflow=1.42 cfs 3.371 af MSE 24-hr 3 2-Year Rainfall=2.87"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 8HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Summary for Pond 1P: FILTRATION/POND Inflow Area = 20.722 ac, 40.63% Impervious, Inflow Depth = 1.75" for 2-Year event Inflow = 46.18 cfs @ 12.15 hrs, Volume= 3.019 af Outflow = 1.25 cfs @ 15.15 hrs, Volume= 2.986 af, Atten= 97%, Lag= 180.0 min Primary = 1.25 cfs @ 15.15 hrs, Volume= 2.986 af Routed to Pond 10P : West Existing Wetland Routing by Dyn-Stor-Ind method, Time Span= 0.00-600.00 hrs, dt= 0.01 hrs Starting Elev= 994.00' Surf.Area= 79,538 sf Storage= 81,734 cf Peak Elev= 996.03' @ 15.15 hrs Surf.Area= 87,381 sf Storage= 182,508 cf (100,773 cf above start) Plug-Flow detention time= 10,951.2 min calculated for 1.110 af (37% of inflow) Center-of-Mass det. time= 4,447.6 min ( 5,230.2 - 782.6 ) Volume Invert Avail.Storage Storage Description #1 990.00' 16,621 cf West Forebay (Prismatic) Listed below (Recalc) #2 993.50' 1,512 cf West shallow wetland (Prismatic) Listed below (Recalc) #3 990.00' 18,942 cf Remnant Wetland (Prismatic) Listed below (Recalc) #4 989.00' 40,676 cf Middle Forebay (Prismatic) Listed below (Recalc) #5 993.50' 665 cf East shallow wetland (Prismatic) Listed below (Recalc) #6 992.90' 3,319 cf Filtration (Prismatic) Listed below (Recalc) -Impervious 11,062 cf Overall x 30.0% Voids #7 994.00' 336,232 cf Live Storage (Prismatic) Listed below (Recalc) 417,966 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 990.00 2,425 0 0 992.00 4,029 6,454 6,454 994.00 6,138 10,167 16,621 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 993.50 2,312 0 0 994.00 3,736 1,512 1,512 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 990.00 1,596 0 0 992.00 4,761 6,357 6,357 994.00 7,824 12,585 18,942 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 989.00 4,873 0 0 990.00 5,939 5,406 5,406 991.00 7,021 6,480 11,886 993.00 9,598 16,619 28,505 994.00 14,744 12,171 40,676 MSE 24-hr 3 2-Year Rainfall=2.87"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 9HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 993.50 961 0 0 994.00 1,698 665 665 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 992.90 10,056 0 0 994.00 10,057 11,062 11,062 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 994.00 45,398 0 0 995.00 49,888 47,643 47,643 996.00 53,188 51,538 99,181 998.00 56,729 109,917 209,098 1,000.00 70,405 127,134 336,232 Device Routing Invert Outlet Devices #1 Primary 991.10'12.0" Round Culvert L= 246.4' RCP, rounded edge headwall, Ke= 0.100 Inlet / Outlet Invert= 991.10' / 990.02' S= 0.0044 '/' Cc= 0.900 n= 0.013 Concrete sewer w/manholes & inlets, Flow Area= 0.79 sf #2 Device 1 998.90'5.0' long x 0.5' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 Coef. (English) 2.80 2.92 3.08 3.30 3.32 #3 Device 1 994.00'0.800 in/hr Filtration over Surface area above 994.00' Excluded Surface area = 79,538 sf #4 Device 1 995.00'7.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=1.25 cfs @ 15.15 hrs HW=996.03' TW=974.30' (Dynamic Tailwater) 1=Culvert (Passes 1.25 cfs of 4.75 cfs potential flow) 2=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) 3=Filtration (Exfiltration Controls 0.15 cfs) 4=Orifice/Grate (Orifice Controls 1.11 cfs @ 4.14 fps) MSE 24-hr 3 2-Year Rainfall=2.87"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 10HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Pond 1P: FILTRATION/POND Inflow Primary Hydrograph Time (hours) 600550500450400350300250200150100500Flow (cfs)50 45 40 35 30 25 20 15 10 5 0 Inflow Area=20.722 ac Peak Elev=996.03' Storage=182,508 cf 46.18 cfs 1.25 cfs MSE 24-hr 3 2-Year Rainfall=2.87"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 11HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 1P: FILTRATION/POND Time (hours) Inflow (cfs) Storage (cubic-feet) Elevation (feet) Primary (cfs) 0.00 0.00 81,734 994.00 0.00 20.00 0.54 175,056 995.89 1.13 40.00 0.00 138,005 995.17 0.19 60.00 0.00 129,737 995.01 0.08 80.00 0.00 124,056 994.89 0.07 100.00 0.00 119,023 994.79 0.07 120.00 0.00 114,569 994.70 0.06 140.00 0.00 110,632 994.62 0.05 160.00 0.00 107,156 994.55 0.05 180.00 0.00 104,088 994.48 0.04 200.00 0.00 101,383 994.42 0.04 220.00 0.00 98,999 994.37 0.03 240.00 0.00 96,900 994.33 0.03 260.00 0.00 95,053 994.29 0.02 280.00 0.00 93,428 994.25 0.02 300.00 0.00 91,999 994.22 0.02 320.00 0.00 90,743 994.20 0.02 340.00 0.00 89,639 994.17 0.01 360.00 0.00 88,670 994.15 0.01 380.00 0.00 87,819 994.13 0.01 400.00 0.00 87,071 994.12 0.01 420.00 0.00 86,415 994.10 0.01 440.00 0.00 85,840 994.09 0.01 460.00 0.00 85,334 994.08 0.01 480.00 0.00 84,891 994.07 0.01 500.00 0.00 84,502 994.06 0.01 520.00 0.00 84,161 994.05 0.00 540.00 0.00 83,862 994.05 0.00 560.00 0.00 83,600 994.04 0.00 580.00 0.00 83,370 994.04 0.00 600.00 0.00 83,168 994.03 0.00 MSE 24-hr 3 2-Year Rainfall=2.87"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 12HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond 1P: FILTRATION/POND Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 989.00 4,873 0 989.20 5,086 996 989.40 5,299 2,034 989.60 5,513 3,116 989.80 5,726 4,240 990.00 9,960 5,406 990.20 10,653 7,467 990.40 11,347 9,667 990.60 12,040 12,006 990.80 12,733 14,483 991.00 13,427 17,099 991.20 14,161 19,858 991.40 14,896 22,764 991.60 15,630 25,816 991.80 16,365 29,016 992.00 17,100 32,362 992.20 17,874 35,860 992.40 18,649 39,512 992.60 19,424 43,319 992.80 20,199 47,282 993.00 20,974 51,701 993.20 22,520 56,653 993.40 24,067 61,916 993.60 29,318 67,836 993.80 31,729 74,544 994.00 79,538 81,734 994.20 80,436 90,904 994.40 81,334 100,253 994.60 82,232 109,781 994.80 83,130 119,490 995.00 84,028 129,377 995.20 84,688 139,421 995.40 85,348 149,597 995.60 86,008 159,904 995.80 86,668 170,344 996.00 87,328 180,915 996.20 87,682 191,588 996.40 88,036 202,332 996.60 88,390 213,147 996.80 88,744 224,032 997.00 89,099 234,989 997.20 89,453 246,016 997.40 89,807 257,114 997.60 90,161 268,282 997.80 90,515 279,522 998.00 90,869 290,832 998.20 92,237 302,315 998.40 93,604 314,071 998.60 94,972 326,101 998.80 96,339 338,404 999.00 97,707 350,980 999.20 99,075 363,831 Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 999.40 100,442 376,954 999.60 101,810 390,351 999.80 103,177 404,022 1,000.00 104,545 417,966 MSE 24-hr 3 2-Year Rainfall=2.87"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 13HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Summary for Pond 8P: West Filtration Basin Inflow Area = 2.882 ac, 23.70% Impervious, Inflow Depth = 1.47" for 2-Year event Inflow = 7.72 cfs @ 12.13 hrs, Volume= 0.354 af Outflow = 3.34 cfs @ 12.22 hrs, Volume= 0.354 af, Atten= 57%, Lag= 5.8 min Primary = 3.34 cfs @ 12.22 hrs, Volume= 0.354 af Routed to Pond 10P : West Existing Wetland Routing by Dyn-Stor-Ind method, Time Span= 0.00-600.00 hrs, dt= 0.01 hrs Peak Elev= 996.78' @ 12.22 hrs Surf.Area= 3,871 sf Storage= 6,498 cf Plug-Flow detention time= 609.3 min calculated for 0.354 af (100% of inflow) Center-of-Mass det. time= 609.5 min ( 1,400.6 - 791.2 ) Volume Invert Avail.Storage Storage Description #1 994.00' 15,051 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 994.00 1,035 0 0 995.00 1,919 1,477 1,477 996.00 2,862 2,391 3,868 998.00 5,445 8,307 12,175 998.50 6,062 2,877 15,051 Device Routing Invert Outlet Devices #1 Primary 992.42'18.0" Round Culvert L= 32.9' CMP, mitered to conform to fill, Ke= 0.700 Inlet / Outlet Invert= 992.42' / 989.52' S= 0.0881 '/' Cc= 0.900 n= 0.025 Corrugated metal, Flow Area= 1.77 sf #2 Device 1 994.00'0.800 in/hr Filtration over Surface area above 994.00' Excluded Surface area = 1,035 sf #3 Device 1 996.50'5.0' long x 0.5' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 Coef. (English) 2.80 2.92 3.08 3.30 3.32 #4 Primary 996.00'8.0" W x 6.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=3.33 cfs @ 12.22 hrs HW=996.78' TW=974.14' (Dynamic Tailwater) 1=Culvert (Passes 2.18 cfs of 14.27 cfs potential flow) 2=Filtration (Exfiltration Controls 0.05 cfs) 3=Broad-Crested Rectangular Weir (Weir Controls 2.12 cfs @ 1.51 fps) 4=Orifice/Grate (Orifice Controls 1.16 cfs @ 3.48 fps) MSE 24-hr 3 2-Year Rainfall=2.87"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 14HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Pond 8P: West Filtration Basin Inflow Primary Hydrograph Time (hours) 600550500450400350300250200150100500Flow (cfs)8 7 6 5 4 3 2 1 0 Inflow Area=2.882 ac Peak Elev=996.78' Storage=6,498 cf 7.72 cfs 3.34 cfs MSE 24-hr 3 2-Year Rainfall=2.87"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 15HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 8P: West Filtration Basin Time (hours) Inflow (cfs) Storage (cubic-feet) Elevation (feet) Primary (cfs) 0.00 0.00 0 994.00 0.00 20.00 0.07 4,087 996.08 0.08 40.00 0.00 2,267 995.38 0.02 60.00 0.00 1,025 994.75 0.01 80.00 0.00 404 994.34 0.01 100.00 0.00 143 994.13 0.00 120.00 0.00 47 994.04 0.00 140.00 0.00 15 994.01 0.00 160.00 0.00 5 994.00 0.00 180.00 0.00 2 994.00 0.00 200.00 0.00 1 994.00 0.00 220.00 0.00 0 994.00 0.00 240.00 0.00 0 994.00 0.00 260.00 0.00 0 994.00 0.00 280.00 0.00 0 994.00 0.00 300.00 0.00 0 994.00 0.00 320.00 0.00 0 994.00 0.00 340.00 0.00 0 994.00 0.00 360.00 0.00 0 994.00 0.00 380.00 0.00 0 994.00 0.00 400.00 0.00 0 994.00 0.00 420.00 0.00 0 994.00 0.00 440.00 0.00 0 994.00 0.00 460.00 0.00 0 994.00 0.00 480.00 0.00 0 994.00 0.00 500.00 0.00 0 994.00 0.00 520.00 0.00 0 994.00 0.00 540.00 0.00 0 994.00 0.00 560.00 0.00 0 994.00 0.00 580.00 0.00 0 994.00 0.00 600.00 0.00 0 994.00 0.00 MSE 24-hr 3 2-Year Rainfall=2.87"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 16HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond 8P: West Filtration Basin Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 994.00 1,035 0 994.05 1,079 53 994.10 1,123 108 994.15 1,168 165 994.20 1,212 225 994.25 1,256 286 994.30 1,300 350 994.35 1,344 416 994.40 1,389 485 994.45 1,433 555 994.50 1,477 628 994.55 1,521 703 994.60 1,565 780 994.65 1,610 859 994.70 1,654 941 994.75 1,698 1,025 994.80 1,742 1,111 994.85 1,786 1,199 994.90 1,831 1,290 994.95 1,875 1,382 995.00 1,919 1,477 995.05 1,966 1,574 995.10 2,013 1,674 995.15 2,060 1,775 995.20 2,108 1,880 995.25 2,155 1,986 995.30 2,202 2,095 995.35 2,249 2,206 995.40 2,296 2,320 995.45 2,343 2,436 995.50 2,391 2,554 995.55 2,438 2,675 995.60 2,485 2,798 995.65 2,532 2,924 995.70 2,579 3,051 995.75 2,626 3,181 995.80 2,673 3,314 995.85 2,721 3,449 995.90 2,768 3,586 995.95 2,815 3,726 996.00 2,862 3,868 996.05 2,927 4,012 996.10 2,991 4,160 996.15 3,056 4,311 996.20 3,120 4,466 996.25 3,185 4,623 996.30 3,249 4,784 996.35 3,314 4,948 996.40 3,379 5,116 996.45 3,443 5,286 996.50 3,508 5,460 996.55 3,572 5,637 Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 996.60 3,637 5,817 996.65 3,701 6,001 996.70 3,766 6,187 996.75 3,831 6,377 996.80 3,895 6,570 996.85 3,960 6,767 996.90 4,024 6,966 996.95 4,089 7,169 997.00 4,154 7,375 997.05 4,218 7,585 997.10 4,283 7,797 997.15 4,347 8,013 997.20 4,412 8,232 997.25 4,476 8,454 997.30 4,541 8,679 997.35 4,606 8,908 997.40 4,670 9,140 997.45 4,735 9,375 997.50 4,799 9,613 997.55 4,864 9,855 997.60 4,928 10,100 997.65 4,993 10,348 997.70 5,058 10,599 997.75 5,122 10,854 997.80 5,187 11,111 997.85 5,251 11,372 997.90 5,316 11,636 997.95 5,380 11,904 998.00 5,445 12,175 998.05 5,507 12,448 998.10 5,568 12,725 998.15 5,630 13,005 998.20 5,692 13,288 998.25 5,754 13,574 998.30 5,815 13,864 998.35 5,877 14,156 998.40 5,939 14,451 998.45 6,000 14,750 998.50 6,062 15,051 MSE 24-hr 3 2-Year Rainfall=2.87"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 17HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Summary for Pond 10P: West Existing Wetland Inflow Area = 23.892 ac, 38.10% Impervious, Inflow Depth > 1.70" for 2-Year event Inflow = 3.81 cfs @ 12.24 hrs, Volume= 3.375 af Outflow = 1.42 cfs @ 15.75 hrs, Volume= 3.371 af, Atten= 63%, Lag= 210.3 min Primary = 1.42 cfs @ 15.75 hrs, Volume= 3.371 af Routed to Link 7L : TOTAL Routing by Dyn-Stor-Ind method, Time Span= 0.00-600.00 hrs, dt= 0.01 hrs Starting Elev= 974.10' Surf.Area= 54,326 sf Storage= 5,411 cf Peak Elev= 974.30' @ 15.75 hrs Surf.Area= 55,210 sf Storage= 16,578 cf (11,167 cf above start) Plug-Flow detention time= 1,259.4 min calculated for 3.246 af (96% of inflow) Center-of-Mass det. time= 224.5 min ( 5,007.7 - 4,783.1 ) Volume Invert Avail.Storage Storage Description #1 974.00' 487,616 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 974.00 53,893 0 0 975.00 58,226 56,060 56,060 976.00 62,886 60,556 116,616 977.00 67,093 64,990 181,605 978.00 71,582 69,338 250,943 979.00 76,083 73,833 324,775 980.00 81,311 78,697 403,472 981.00 86,977 84,144 487,616 Device Routing Invert Outlet Devices #1 Primary 974.10'18.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=1.42 cfs @ 15.75 hrs HW=974.30' TW=0.00' (Dynamic Tailwater) 1=Orifice/Grate (Weir Controls 1.42 cfs @ 1.48 fps) MSE 24-hr 3 2-Year Rainfall=2.87"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 18HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Pond 10P: West Existing Wetland Inflow Primary Hydrograph Time (hours) 600550500450400350300250200150100500Flow (cfs)4 3 2 1 0 Inflow Area=23.892 ac Peak Elev=974.30' Storage=16,578 cf 3.81 cfs 1.42 cfs MSE 24-hr 3 2-Year Rainfall=2.87"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 19HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 10P: West Existing Wetland Time (hours) Inflow (cfs) Storage (cubic-feet) Elevation (feet) Primary (cfs) 0.00 0.00 5,411 974.10 0.00 20.00 1.22 15,855 974.29 1.28 40.00 0.21 9,006 974.17 0.26 60.00 0.10 7,344 974.14 0.10 80.00 0.08 7,076 974.13 0.08 100.00 0.07 6,902 974.13 0.07 120.00 0.06 6,765 974.12 0.06 140.00 0.05 6,651 974.12 0.05 160.00 0.05 6,550 974.12 0.05 180.00 0.04 6,459 974.12 0.04 200.00 0.04 6,375 974.12 0.04 220.00 0.03 6,297 974.12 0.03 240.00 0.03 6,226 974.11 0.03 260.00 0.02 6,160 974.11 0.02 280.00 0.02 6,099 974.11 0.02 300.00 0.02 6,043 974.11 0.02 320.00 0.02 5,992 974.11 0.02 340.00 0.01 5,944 974.11 0.01 360.00 0.01 5,901 974.11 0.01 380.00 0.01 5,861 974.11 0.01 400.00 0.01 5,824 974.11 0.01 420.00 0.01 5,790 974.11 0.01 440.00 0.01 5,759 974.11 0.01 460.00 0.01 5,730 974.11 0.01 480.00 0.01 5,704 974.11 0.01 500.00 0.01 5,680 974.10 0.01 520.00 0.00 5,658 974.10 0.00 540.00 0.00 5,637 974.10 0.00 560.00 0.00 5,619 974.10 0.00 580.00 0.00 5,602 974.10 0.00 600.00 0.00 5,586 974.10 0.00 MSE 24-hr 3 2-Year Rainfall=2.87"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 20HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond 10P: West Existing Wetland Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 974.00 53,893 0 974.10 54,326 5,411 974.20 54,760 10,865 974.30 55,193 16,363 974.40 55,626 21,904 974.50 56,060 27,488 974.60 56,493 33,116 974.70 56,926 38,787 974.80 57,359 44,501 974.90 57,793 50,259 975.00 58,226 56,060 975.10 58,692 61,905 975.20 59,158 67,798 975.30 59,624 73,737 975.40 60,090 79,723 975.50 60,556 85,755 975.60 61,022 91,834 975.70 61,488 97,959 975.80 61,954 104,131 975.90 62,420 110,350 976.00 62,886 116,616 976.10 63,307 122,925 976.20 63,727 129,277 976.30 64,148 135,671 976.40 64,569 142,106 976.50 64,990 148,584 976.60 65,410 155,104 976.70 65,831 161,666 976.80 66,252 168,271 976.90 66,672 174,917 977.00 67,093 181,605 977.10 67,542 188,337 977.20 67,991 195,113 977.30 68,440 201,935 977.40 68,889 208,801 977.50 69,338 215,713 977.60 69,786 222,669 977.70 70,235 229,670 977.80 70,684 236,716 977.90 71,133 243,807 978.00 71,582 250,943 978.10 72,032 258,123 978.20 72,482 265,349 978.30 72,932 272,620 978.40 73,382 279,935 978.50 73,833 287,296 978.60 74,283 294,702 978.70 74,733 302,153 978.80 75,183 309,648 978.90 75,633 317,189 979.00 76,083 324,775 979.10 76,606 332,409 Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 979.20 77,129 340,096 979.30 77,651 347,835 979.40 78,174 355,626 979.50 78,697 363,470 979.60 79,220 371,366 979.70 79,743 379,314 979.80 80,265 387,314 979.90 80,788 395,367 980.00 81,311 403,472 980.10 81,878 411,631 980.20 82,444 419,848 980.30 83,011 428,120 980.40 83,577 436,450 980.50 84,144 444,836 980.60 84,711 453,278 980.70 85,277 461,778 980.80 85,844 470,334 980.90 86,410 478,947 981.00 86,977 487,616 MSE 24-hr 3 10-Year Rainfall=4.26"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 21HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Time span=0.00-600.00 hrs, dt=0.01 hrs, 60001 points Runoff by SCS TR-20 method, UH=SCS, Weighted-Q Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Peak Elev=997.34' Storage=253,654 cf Inflow=78.77 cfs 5.118 afPond 1P: FILTRATION/POND Outflow=2.03 cfs 5.083 af Peak Elev=997.22' Storage=8,298 cf Inflow=13.81 cfs 0.632 afPond 8P: West Filtration Basin Outflow=11.33 cfs 0.632 af Peak Elev=974.41' Storage=22,392 cf Inflow=12.85 cfs 5.778 afPond 10P: West Existing Wetland Outflow=2.64 cfs 5.774 af MSE 24-hr 3 10-Year Rainfall=4.26"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 22HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Summary for Pond 1P: FILTRATION/POND Inflow Area = 20.722 ac, 40.63% Impervious, Inflow Depth = 2.96" for 10-Year event Inflow = 78.77 cfs @ 12.14 hrs, Volume= 5.118 af Outflow = 2.03 cfs @ 15.14 hrs, Volume= 5.083 af, Atten= 97%, Lag= 179.9 min Primary = 2.03 cfs @ 15.14 hrs, Volume= 5.083 af Routed to Pond 10P : West Existing Wetland Routing by Dyn-Stor-Ind method, Time Span= 0.00-600.00 hrs, dt= 0.01 hrs Starting Elev= 994.00' Surf.Area= 79,538 sf Storage= 81,734 cf Peak Elev= 997.34' @ 15.14 hrs Surf.Area= 89,697 sf Storage= 253,654 cf (171,920 cf above start) Plug-Flow detention time= 4,916.7 min calculated for 3.206 af (63% of inflow) Center-of-Mass det. time= 3,161.8 min ( 3,938.7 - 776.9 ) Volume Invert Avail.Storage Storage Description #1 990.00' 16,621 cf West Forebay (Prismatic) Listed below (Recalc) #2 993.50' 1,512 cf West shallow wetland (Prismatic) Listed below (Recalc) #3 990.00' 18,942 cf Remnant Wetland (Prismatic) Listed below (Recalc) #4 989.00' 40,676 cf Middle Forebay (Prismatic) Listed below (Recalc) #5 993.50' 665 cf East shallow wetland (Prismatic) Listed below (Recalc) #6 992.90' 3,319 cf Filtration (Prismatic) Listed below (Recalc) -Impervious 11,062 cf Overall x 30.0% Voids #7 994.00' 336,232 cf Live Storage (Prismatic) Listed below (Recalc) 417,966 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 990.00 2,425 0 0 992.00 4,029 6,454 6,454 994.00 6,138 10,167 16,621 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 993.50 2,312 0 0 994.00 3,736 1,512 1,512 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 990.00 1,596 0 0 992.00 4,761 6,357 6,357 994.00 7,824 12,585 18,942 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 989.00 4,873 0 0 990.00 5,939 5,406 5,406 991.00 7,021 6,480 11,886 993.00 9,598 16,619 28,505 994.00 14,744 12,171 40,676 MSE 24-hr 3 10-Year Rainfall=4.26"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 23HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 993.50 961 0 0 994.00 1,698 665 665 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 992.90 10,056 0 0 994.00 10,057 11,062 11,062 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 994.00 45,398 0 0 995.00 49,888 47,643 47,643 996.00 53,188 51,538 99,181 998.00 56,729 109,917 209,098 1,000.00 70,405 127,134 336,232 Device Routing Invert Outlet Devices #1 Primary 991.10'12.0" Round Culvert L= 246.4' RCP, rounded edge headwall, Ke= 0.100 Inlet / Outlet Invert= 991.10' / 990.02' S= 0.0044 '/' Cc= 0.900 n= 0.013 Concrete sewer w/manholes & inlets, Flow Area= 0.79 sf #2 Device 1 998.90'5.0' long x 0.5' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 Coef. (English) 2.80 2.92 3.08 3.30 3.32 #3 Device 1 994.00'0.800 in/hr Filtration over Surface area above 994.00' Excluded Surface area = 79,538 sf #4 Device 1 995.00'7.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=2.03 cfs @ 15.14 hrs HW=997.34' TW=974.40' (Dynamic Tailwater) 1=Culvert (Passes 2.03 cfs of 5.33 cfs potential flow) 2=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) 3=Filtration (Exfiltration Controls 0.19 cfs) 4=Orifice/Grate (Orifice Controls 1.84 cfs @ 6.89 fps) MSE 24-hr 3 10-Year Rainfall=4.26"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 24HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Pond 1P: FILTRATION/POND Inflow Primary Hydrograph Time (hours) 600550500450400350300250200150100500Flow (cfs)85 80 75 70 65 60 55 50 45 40 35 30 25 20 15 10 5 0 Inflow Area=20.722 ac Peak Elev=997.34' Storage=253,654 cf 78.77 cfs 2.03 cfs MSE 24-hr 3 10-Year Rainfall=4.26"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 25HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 1P: FILTRATION/POND Time (hours) Inflow (cfs) Storage (cubic-feet) Elevation (feet) Primary (cfs) 0.00 0.00 81,734 994.00 0.00 20.00 0.86 240,792 997.11 1.91 40.00 0.00 153,041 995.47 0.65 60.00 0.00 133,774 995.09 0.11 80.00 0.00 127,338 994.96 0.08 100.00 0.00 121,930 994.85 0.07 120.00 0.00 117,141 994.75 0.06 140.00 0.00 112,906 994.66 0.06 160.00 0.00 109,163 994.59 0.05 180.00 0.00 105,859 994.52 0.04 200.00 0.00 102,944 994.46 0.04 220.00 0.00 100,374 994.40 0.03 240.00 0.00 98,111 994.35 0.03 260.00 0.00 96,119 994.31 0.03 280.00 0.00 94,365 994.27 0.02 300.00 0.00 92,823 994.24 0.02 320.00 0.00 91,467 994.21 0.02 340.00 0.00 90,276 994.19 0.02 360.00 0.00 89,229 994.16 0.01 380.00 0.00 88,310 994.14 0.01 400.00 0.00 87,502 994.13 0.01 420.00 0.00 86,794 994.11 0.01 440.00 0.00 86,172 994.10 0.01 460.00 0.00 85,626 994.09 0.01 480.00 0.00 85,147 994.07 0.01 500.00 0.00 84,726 994.07 0.01 520.00 0.00 84,358 994.06 0.00 540.00 0.00 84,035 994.05 0.00 560.00 0.00 83,751 994.04 0.00 580.00 0.00 83,502 994.04 0.00 600.00 0.00 83,284 994.03 0.00 MSE 24-hr 3 10-Year Rainfall=4.26"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 26HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond 1P: FILTRATION/POND Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 989.00 4,873 0 989.20 5,086 996 989.40 5,299 2,034 989.60 5,513 3,116 989.80 5,726 4,240 990.00 9,960 5,406 990.20 10,653 7,467 990.40 11,347 9,667 990.60 12,040 12,006 990.80 12,733 14,483 991.00 13,427 17,099 991.20 14,161 19,858 991.40 14,896 22,764 991.60 15,630 25,816 991.80 16,365 29,016 992.00 17,100 32,362 992.20 17,874 35,860 992.40 18,649 39,512 992.60 19,424 43,319 992.80 20,199 47,282 993.00 20,974 51,701 993.20 22,520 56,653 993.40 24,067 61,916 993.60 29,318 67,836 993.80 31,729 74,544 994.00 79,538 81,734 994.20 80,436 90,904 994.40 81,334 100,253 994.60 82,232 109,781 994.80 83,130 119,490 995.00 84,028 129,377 995.20 84,688 139,421 995.40 85,348 149,597 995.60 86,008 159,904 995.80 86,668 170,344 996.00 87,328 180,915 996.20 87,682 191,588 996.40 88,036 202,332 996.60 88,390 213,147 996.80 88,744 224,032 997.00 89,099 234,989 997.20 89,453 246,016 997.40 89,807 257,114 997.60 90,161 268,282 997.80 90,515 279,522 998.00 90,869 290,832 998.20 92,237 302,315 998.40 93,604 314,071 998.60 94,972 326,101 998.80 96,339 338,404 999.00 97,707 350,980 999.20 99,075 363,831 Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 999.40 100,442 376,954 999.60 101,810 390,351 999.80 103,177 404,022 1,000.00 104,545 417,966 MSE 24-hr 3 10-Year Rainfall=4.26"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 27HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Summary for Pond 8P: West Filtration Basin Inflow Area = 2.882 ac, 23.70% Impervious, Inflow Depth = 2.63" for 10-Year event Inflow = 13.81 cfs @ 12.13 hrs, Volume= 0.632 af Outflow = 11.33 cfs @ 12.16 hrs, Volume= 0.632 af, Atten= 18%, Lag= 2.1 min Primary = 11.33 cfs @ 12.16 hrs, Volume= 0.632 af Routed to Pond 10P : West Existing Wetland Routing by Dyn-Stor-Ind method, Time Span= 0.00-600.00 hrs, dt= 0.01 hrs Peak Elev= 997.22' @ 12.16 hrs Surf.Area= 4,431 sf Storage= 8,298 cf Plug-Flow detention time= 358.3 min calculated for 0.632 af (100% of inflow) Center-of-Mass det. time= 358.5 min ( 1,142.4 - 783.9 ) Volume Invert Avail.Storage Storage Description #1 994.00' 15,051 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 994.00 1,035 0 0 995.00 1,919 1,477 1,477 996.00 2,862 2,391 3,868 998.00 5,445 8,307 12,175 998.50 6,062 2,877 15,051 Device Routing Invert Outlet Devices #1 Primary 992.42'18.0" Round Culvert L= 32.9' CMP, mitered to conform to fill, Ke= 0.700 Inlet / Outlet Invert= 992.42' / 989.52' S= 0.0881 '/' Cc= 0.900 n= 0.025 Corrugated metal, Flow Area= 1.77 sf #2 Device 1 994.00'0.800 in/hr Filtration over Surface area above 994.00' Excluded Surface area = 1,035 sf #3 Device 1 996.50'5.0' long x 0.5' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 Coef. (English) 2.80 2.92 3.08 3.30 3.32 #4 Primary 996.00'8.0" W x 6.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=11.33 cfs @ 12.16 hrs HW=997.21' TW=974.21' (Dynamic Tailwater) 1=Culvert (Passes 9.75 cfs of 15.10 cfs potential flow) 2=Filtration (Exfiltration Controls 0.06 cfs) 3=Broad-Crested Rectangular Weir (Weir Controls 9.69 cfs @ 2.71 fps) 4=Orifice/Grate (Orifice Controls 1.57 cfs @ 4.72 fps) MSE 24-hr 3 10-Year Rainfall=4.26"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 28HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Pond 8P: West Filtration Basin Inflow Primary Hydrograph Time (hours) 600550500450400350300250200150100500Flow (cfs)15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Inflow Area=2.882 ac Peak Elev=997.22' Storage=8,298 cf 13.81 cfs 11.33 cfs MSE 24-hr 3 10-Year Rainfall=4.26"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 29HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 8P: West Filtration Basin Time (hours) Inflow (cfs) Storage (cubic-feet) Elevation (feet) Primary (cfs) 0.00 0.00 0 994.00 0.00 20.00 0.11 4,228 996.12 0.13 40.00 0.00 2,313 995.40 0.02 60.00 0.00 1,050 994.76 0.01 80.00 0.00 415 994.35 0.01 100.00 0.00 147 994.13 0.00 120.00 0.00 49 994.05 0.00 140.00 0.00 16 994.02 0.00 160.00 0.00 5 994.00 0.00 180.00 0.00 2 994.00 0.00 200.00 0.00 1 994.00 0.00 220.00 0.00 0 994.00 0.00 240.00 0.00 0 994.00 0.00 260.00 0.00 0 994.00 0.00 280.00 0.00 0 994.00 0.00 300.00 0.00 0 994.00 0.00 320.00 0.00 0 994.00 0.00 340.00 0.00 0 994.00 0.00 360.00 0.00 0 994.00 0.00 380.00 0.00 0 994.00 0.00 400.00 0.00 0 994.00 0.00 420.00 0.00 0 994.00 0.00 440.00 0.00 0 994.00 0.00 460.00 0.00 0 994.00 0.00 480.00 0.00 0 994.00 0.00 500.00 0.00 0 994.00 0.00 520.00 0.00 0 994.00 0.00 540.00 0.00 0 994.00 0.00 560.00 0.00 0 994.00 0.00 580.00 0.00 0 994.00 0.00 600.00 0.00 0 994.00 0.00 MSE 24-hr 3 10-Year Rainfall=4.26"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 30HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond 8P: West Filtration Basin Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 994.00 1,035 0 994.05 1,079 53 994.10 1,123 108 994.15 1,168 165 994.20 1,212 225 994.25 1,256 286 994.30 1,300 350 994.35 1,344 416 994.40 1,389 485 994.45 1,433 555 994.50 1,477 628 994.55 1,521 703 994.60 1,565 780 994.65 1,610 859 994.70 1,654 941 994.75 1,698 1,025 994.80 1,742 1,111 994.85 1,786 1,199 994.90 1,831 1,290 994.95 1,875 1,382 995.00 1,919 1,477 995.05 1,966 1,574 995.10 2,013 1,674 995.15 2,060 1,775 995.20 2,108 1,880 995.25 2,155 1,986 995.30 2,202 2,095 995.35 2,249 2,206 995.40 2,296 2,320 995.45 2,343 2,436 995.50 2,391 2,554 995.55 2,438 2,675 995.60 2,485 2,798 995.65 2,532 2,924 995.70 2,579 3,051 995.75 2,626 3,181 995.80 2,673 3,314 995.85 2,721 3,449 995.90 2,768 3,586 995.95 2,815 3,726 996.00 2,862 3,868 996.05 2,927 4,012 996.10 2,991 4,160 996.15 3,056 4,311 996.20 3,120 4,466 996.25 3,185 4,623 996.30 3,249 4,784 996.35 3,314 4,948 996.40 3,379 5,116 996.45 3,443 5,286 996.50 3,508 5,460 996.55 3,572 5,637 Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 996.60 3,637 5,817 996.65 3,701 6,001 996.70 3,766 6,187 996.75 3,831 6,377 996.80 3,895 6,570 996.85 3,960 6,767 996.90 4,024 6,966 996.95 4,089 7,169 997.00 4,154 7,375 997.05 4,218 7,585 997.10 4,283 7,797 997.15 4,347 8,013 997.20 4,412 8,232 997.25 4,476 8,454 997.30 4,541 8,679 997.35 4,606 8,908 997.40 4,670 9,140 997.45 4,735 9,375 997.50 4,799 9,613 997.55 4,864 9,855 997.60 4,928 10,100 997.65 4,993 10,348 997.70 5,058 10,599 997.75 5,122 10,854 997.80 5,187 11,111 997.85 5,251 11,372 997.90 5,316 11,636 997.95 5,380 11,904 998.00 5,445 12,175 998.05 5,507 12,448 998.10 5,568 12,725 998.15 5,630 13,005 998.20 5,692 13,288 998.25 5,754 13,574 998.30 5,815 13,864 998.35 5,877 14,156 998.40 5,939 14,451 998.45 6,000 14,750 998.50 6,062 15,051 MSE 24-hr 3 10-Year Rainfall=4.26"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 31HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Summary for Pond 10P: West Existing Wetland Inflow Area = 23.892 ac, 38.10% Impervious, Inflow Depth > 2.90" for 10-Year event Inflow = 12.85 cfs @ 12.16 hrs, Volume= 5.778 af Outflow = 2.64 cfs @ 13.83 hrs, Volume= 5.774 af, Atten= 79%, Lag= 99.8 min Primary = 2.64 cfs @ 13.83 hrs, Volume= 5.774 af Routed to Link 7L : TOTAL Routing by Dyn-Stor-Ind method, Time Span= 0.00-600.00 hrs, dt= 0.01 hrs Starting Elev= 974.10' Surf.Area= 54,326 sf Storage= 5,411 cf Peak Elev= 974.41' @ 13.83 hrs Surf.Area= 55,664 sf Storage= 22,392 cf (16,981 cf above start) Plug-Flow detention time= 779.9 min calculated for 5.650 af (98% of inflow) Center-of-Mass det. time= 174.6 min ( 3,772.8 - 3,598.2 ) Volume Invert Avail.Storage Storage Description #1 974.00' 487,616 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 974.00 53,893 0 0 975.00 58,226 56,060 56,060 976.00 62,886 60,556 116,616 977.00 67,093 64,990 181,605 978.00 71,582 69,338 250,943 979.00 76,083 73,833 324,775 980.00 81,311 78,697 403,472 981.00 86,977 84,144 487,616 Device Routing Invert Outlet Devices #1 Primary 974.10'18.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=2.64 cfs @ 13.83 hrs HW=974.41' TW=0.00' (Dynamic Tailwater) 1=Orifice/Grate (Weir Controls 2.64 cfs @ 1.82 fps) MSE 24-hr 3 10-Year Rainfall=4.26"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 32HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Pond 10P: West Existing Wetland Inflow Primary Hydrograph Time (hours) 600550500450400350300250200150100500Flow (cfs)14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Inflow Area=23.892 ac Peak Elev=974.41' Storage=22,392 cf 12.85 cfs 2.64 cfs MSE 24-hr 3 10-Year Rainfall=4.26"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 33HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 10P: West Existing Wetland Time (hours) Inflow (cfs) Storage (cubic-feet) Elevation (feet) Primary (cfs) 0.00 0.00 5,411 974.10 0.00 20.00 2.05 20,071 974.37 2.13 40.00 0.67 12,993 974.24 0.80 60.00 0.13 7,896 974.15 0.15 80.00 0.09 7,157 974.13 0.09 100.00 0.07 6,974 974.13 0.08 120.00 0.06 6,832 974.13 0.07 140.00 0.06 6,712 974.12 0.06 160.00 0.05 6,607 974.12 0.05 180.00 0.04 6,511 974.12 0.04 200.00 0.04 6,423 974.12 0.04 220.00 0.03 6,342 974.12 0.03 240.00 0.03 6,268 974.12 0.03 260.00 0.03 6,198 974.11 0.03 280.00 0.02 6,135 974.11 0.02 300.00 0.02 6,076 974.11 0.02 320.00 0.02 6,022 974.11 0.02 340.00 0.02 5,972 974.11 0.02 360.00 0.01 5,926 974.11 0.01 380.00 0.01 5,884 974.11 0.01 400.00 0.01 5,845 974.11 0.01 420.00 0.01 5,810 974.11 0.01 440.00 0.01 5,777 974.11 0.01 460.00 0.01 5,747 974.11 0.01 480.00 0.01 5,720 974.11 0.01 500.00 0.01 5,694 974.11 0.01 520.00 0.00 5,670 974.10 0.01 540.00 0.00 5,649 974.10 0.00 560.00 0.00 5,629 974.10 0.00 580.00 0.00 5,612 974.10 0.00 600.00 0.00 5,595 974.10 0.00 MSE 24-hr 3 10-Year Rainfall=4.26"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 34HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond 10P: West Existing Wetland Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 974.00 53,893 0 974.10 54,326 5,411 974.20 54,760 10,865 974.30 55,193 16,363 974.40 55,626 21,904 974.50 56,060 27,488 974.60 56,493 33,116 974.70 56,926 38,787 974.80 57,359 44,501 974.90 57,793 50,259 975.00 58,226 56,060 975.10 58,692 61,905 975.20 59,158 67,798 975.30 59,624 73,737 975.40 60,090 79,723 975.50 60,556 85,755 975.60 61,022 91,834 975.70 61,488 97,959 975.80 61,954 104,131 975.90 62,420 110,350 976.00 62,886 116,616 976.10 63,307 122,925 976.20 63,727 129,277 976.30 64,148 135,671 976.40 64,569 142,106 976.50 64,990 148,584 976.60 65,410 155,104 976.70 65,831 161,666 976.80 66,252 168,271 976.90 66,672 174,917 977.00 67,093 181,605 977.10 67,542 188,337 977.20 67,991 195,113 977.30 68,440 201,935 977.40 68,889 208,801 977.50 69,338 215,713 977.60 69,786 222,669 977.70 70,235 229,670 977.80 70,684 236,716 977.90 71,133 243,807 978.00 71,582 250,943 978.10 72,032 258,123 978.20 72,482 265,349 978.30 72,932 272,620 978.40 73,382 279,935 978.50 73,833 287,296 978.60 74,283 294,702 978.70 74,733 302,153 978.80 75,183 309,648 978.90 75,633 317,189 979.00 76,083 324,775 979.10 76,606 332,409 Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 979.20 77,129 340,096 979.30 77,651 347,835 979.40 78,174 355,626 979.50 78,697 363,470 979.60 79,220 371,366 979.70 79,743 379,314 979.80 80,265 387,314 979.90 80,788 395,367 980.00 81,311 403,472 980.10 81,878 411,631 980.20 82,444 419,848 980.30 83,011 428,120 980.40 83,577 436,450 980.50 84,144 444,836 980.60 84,711 453,278 980.70 85,277 461,778 980.80 85,844 470,334 980.90 86,410 478,947 981.00 86,977 487,616 MSE 24-hr 3 100-Year Rainfall=7.38"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 35HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Time span=0.00-600.00 hrs, dt=0.01 hrs, 60001 points Runoff by SCS TR-20 method, UH=SCS, Weighted-Q Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Peak Elev=999.86' Storage=408,105 cf Inflow=155.06 cfs 10.155 afPond 1P: FILTRATION/POND Outflow=6.30 cfs 10.116 af Peak Elev=997.95' Storage=11,917 cf Inflow=28.15 cfs 1.316 afPond 8P: West Filtration Basin Outflow=18.51 cfs 1.316 af Peak Elev=974.82' Storage=45,373 cf Inflow=22.59 cfs 11.565 afPond 10P: West Existing Wetland Outflow=7.20 cfs 11.561 af MSE 24-hr 3 100-Year Rainfall=7.38"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 36HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Summary for Pond 1P: FILTRATION/POND Inflow Area = 20.722 ac, 40.63% Impervious, Inflow Depth = 5.88" for 100-Year event Inflow = 155.06 cfs @ 12.14 hrs, Volume= 10.155 af Outflow = 6.30 cfs @ 13.72 hrs, Volume= 10.116 af, Atten= 96%, Lag= 94.7 min Primary = 6.30 cfs @ 13.72 hrs, Volume= 10.116 af Routed to Pond 10P : West Existing Wetland Routing by Dyn-Stor-Ind method, Time Span= 0.00-600.00 hrs, dt= 0.01 hrs Starting Elev= 994.00' Surf.Area= 79,538 sf Storage= 81,734 cf Peak Elev= 999.86' @ 13.72 hrs Surf.Area= 103,581 sf Storage= 408,105 cf (326,370 cf above start) Plug-Flow detention time= 2,657.3 min calculated for 8.240 af (81% of inflow) Center-of-Mass det. time= 2,128.8 min ( 2,897.4 - 768.6 ) Volume Invert Avail.Storage Storage Description #1 990.00' 16,621 cf West Forebay (Prismatic) Listed below (Recalc) #2 993.50' 1,512 cf West shallow wetland (Prismatic) Listed below (Recalc) #3 990.00' 18,942 cf Remnant Wetland (Prismatic) Listed below (Recalc) #4 989.00' 40,676 cf Middle Forebay (Prismatic) Listed below (Recalc) #5 993.50' 665 cf East shallow wetland (Prismatic) Listed below (Recalc) #6 992.90' 3,319 cf Filtration (Prismatic) Listed below (Recalc) -Impervious 11,062 cf Overall x 30.0% Voids #7 994.00' 336,232 cf Live Storage (Prismatic) Listed below (Recalc) 417,966 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 990.00 2,425 0 0 992.00 4,029 6,454 6,454 994.00 6,138 10,167 16,621 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 993.50 2,312 0 0 994.00 3,736 1,512 1,512 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 990.00 1,596 0 0 992.00 4,761 6,357 6,357 994.00 7,824 12,585 18,942 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 989.00 4,873 0 0 990.00 5,939 5,406 5,406 991.00 7,021 6,480 11,886 993.00 9,598 16,619 28,505 994.00 14,744 12,171 40,676 MSE 24-hr 3 100-Year Rainfall=7.38"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 37HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 993.50 961 0 0 994.00 1,698 665 665 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 992.90 10,056 0 0 994.00 10,057 11,062 11,062 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 994.00 45,398 0 0 995.00 49,888 47,643 47,643 996.00 53,188 51,538 99,181 998.00 56,729 109,917 209,098 1,000.00 70,405 127,134 336,232 Device Routing Invert Outlet Devices #1 Primary 991.10'12.0" Round Culvert L= 246.4' RCP, rounded edge headwall, Ke= 0.100 Inlet / Outlet Invert= 991.10' / 990.02' S= 0.0044 '/' Cc= 0.900 n= 0.013 Concrete sewer w/manholes & inlets, Flow Area= 0.79 sf #2 Device 1 998.90'5.0' long x 0.5' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 Coef. (English) 2.80 2.92 3.08 3.30 3.32 #3 Device 1 994.00'0.800 in/hr Filtration over Surface area above 994.00' Excluded Surface area = 79,538 sf #4 Device 1 995.00'7.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=6.30 cfs @ 13.72 hrs HW=999.86' TW=974.81' (Dynamic Tailwater) 1=Culvert (Barrel Controls 6.30 cfs @ 8.03 fps) 2=Broad-Crested Rectangular Weir (Passes < 15.57 cfs potential flow) 3=Filtration (Passes < 0.45 cfs potential flow) 4=Orifice/Grate (Passes < 2.75 cfs potential flow) MSE 24-hr 3 100-Year Rainfall=7.38"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 38HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Pond 1P: FILTRATION/POND Inflow Primary Hydrograph Time (hours) 600550500450400350300250200150100500Flow (cfs)170 160 150 140 130 120 110 100 90 80 70 60 50 40 30 20 10 0 Inflow Area=20.722 ac Peak Elev=999.86' Storage=408,105 cf 155.06 cfs 6.30 cfs MSE 24-hr 3 100-Year Rainfall=7.38"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 39HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 1P: FILTRATION/POND Time (hours) Inflow (cfs) Storage (cubic-feet) Elevation (feet) Primary (cfs) 0.00 0.00 81,734 994.00 0.00 20.00 1.58 349,813 998.98 3.13 40.00 0.00 205,724 996.46 1.55 60.00 0.00 142,220 995.26 0.29 80.00 0.00 131,302 995.04 0.09 100.00 0.00 125,419 994.92 0.08 120.00 0.00 120,230 994.82 0.07 140.00 0.00 115,637 994.72 0.06 160.00 0.00 111,576 994.64 0.05 180.00 0.00 107,989 994.56 0.05 200.00 0.00 104,823 994.50 0.04 220.00 0.00 102,030 994.44 0.04 240.00 0.00 99,570 994.39 0.03 260.00 0.00 97,402 994.34 0.03 280.00 0.00 95,495 994.30 0.02 300.00 0.00 93,817 994.26 0.02 320.00 0.00 92,341 994.23 0.02 340.00 0.00 91,043 994.20 0.02 360.00 0.00 89,903 994.18 0.01 380.00 0.00 88,902 994.16 0.01 400.00 0.00 88,022 994.14 0.01 420.00 0.00 87,250 994.12 0.01 440.00 0.00 86,572 994.11 0.01 460.00 0.00 85,977 994.09 0.01 480.00 0.00 85,455 994.08 0.01 500.00 0.00 84,997 994.07 0.01 520.00 0.00 84,595 994.06 0.01 540.00 0.00 84,243 994.06 0.00 560.00 0.00 83,934 994.05 0.00 580.00 0.00 83,662 994.04 0.00 600.00 0.00 83,425 994.04 0.00 MSE 24-hr 3 100-Year Rainfall=7.38"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 40HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond 1P: FILTRATION/POND Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 989.00 4,873 0 989.20 5,086 996 989.40 5,299 2,034 989.60 5,513 3,116 989.80 5,726 4,240 990.00 9,960 5,406 990.20 10,653 7,467 990.40 11,347 9,667 990.60 12,040 12,006 990.80 12,733 14,483 991.00 13,427 17,099 991.20 14,161 19,858 991.40 14,896 22,764 991.60 15,630 25,816 991.80 16,365 29,016 992.00 17,100 32,362 992.20 17,874 35,860 992.40 18,649 39,512 992.60 19,424 43,319 992.80 20,199 47,282 993.00 20,974 51,701 993.20 22,520 56,653 993.40 24,067 61,916 993.60 29,318 67,836 993.80 31,729 74,544 994.00 79,538 81,734 994.20 80,436 90,904 994.40 81,334 100,253 994.60 82,232 109,781 994.80 83,130 119,490 995.00 84,028 129,377 995.20 84,688 139,421 995.40 85,348 149,597 995.60 86,008 159,904 995.80 86,668 170,344 996.00 87,328 180,915 996.20 87,682 191,588 996.40 88,036 202,332 996.60 88,390 213,147 996.80 88,744 224,032 997.00 89,099 234,989 997.20 89,453 246,016 997.40 89,807 257,114 997.60 90,161 268,282 997.80 90,515 279,522 998.00 90,869 290,832 998.20 92,237 302,315 998.40 93,604 314,071 998.60 94,972 326,101 998.80 96,339 338,404 999.00 97,707 350,980 999.20 99,075 363,831 Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 999.40 100,442 376,954 999.60 101,810 390,351 999.80 103,177 404,022 1,000.00 104,545 417,966 MSE 24-hr 3 100-Year Rainfall=7.38"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 41HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Summary for Pond 8P: West Filtration Basin Inflow Area = 2.882 ac, 23.70% Impervious, Inflow Depth = 5.48" for 100-Year event Inflow = 28.15 cfs @ 12.12 hrs, Volume= 1.316 af Outflow = 18.51 cfs @ 12.18 hrs, Volume= 1.316 af, Atten= 34%, Lag= 3.2 min Primary = 18.51 cfs @ 12.18 hrs, Volume= 1.316 af Routed to Pond 10P : West Existing Wetland Routing by Dyn-Stor-Ind method, Time Span= 0.00-600.00 hrs, dt= 0.01 hrs Peak Elev= 997.95' @ 12.18 hrs Surf.Area= 5,384 sf Storage= 11,917 cf Plug-Flow detention time= 187.6 min calculated for 1.316 af (100% of inflow) Center-of-Mass det. time= 187.5 min ( 961.1 - 773.6 ) Volume Invert Avail.Storage Storage Description #1 994.00' 15,051 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 994.00 1,035 0 0 995.00 1,919 1,477 1,477 996.00 2,862 2,391 3,868 998.00 5,445 8,307 12,175 998.50 6,062 2,877 15,051 Device Routing Invert Outlet Devices #1 Primary 992.42'18.0" Round Culvert L= 32.9' CMP, mitered to conform to fill, Ke= 0.700 Inlet / Outlet Invert= 992.42' / 989.52' S= 0.0881 '/' Cc= 0.900 n= 0.025 Corrugated metal, Flow Area= 1.77 sf #2 Device 1 994.00'0.800 in/hr Filtration over Surface area above 994.00' Excluded Surface area = 1,035 sf #3 Device 1 996.50'5.0' long x 0.5' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 Coef. (English) 2.80 2.92 3.08 3.30 3.32 #4 Primary 996.00'8.0" W x 6.0" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=18.51 cfs @ 12.18 hrs HW=997.95' TW=974.49' (Dynamic Tailwater) 1=Culvert (Inlet Controls 16.42 cfs @ 9.29 fps) 2=Filtration (Passes < 0.08 cfs potential flow) 3=Broad-Crested Rectangular Weir (Passes < 29.01 cfs potential flow) 4=Orifice/Grate (Orifice Controls 2.09 cfs @ 6.27 fps) MSE 24-hr 3 100-Year Rainfall=7.38"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 42HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Pond 8P: West Filtration Basin Inflow Primary Hydrograph Time (hours) 600550500450400350300250200150100500Flow (cfs)30 28 26 24 22 20 18 16 14 12 10 8 6 4 2 0 Inflow Area=2.882 ac Peak Elev=997.95' Storage=11,917 cf 28.15 cfs 18.51 cfs MSE 24-hr 3 100-Year Rainfall=7.38"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 43HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 8P: West Filtration Basin Time (hours) Inflow (cfs) Storage (cubic-feet) Elevation (feet) Primary (cfs) 0.00 0.00 0 994.00 0.00 20.00 0.21 4,479 996.20 0.24 40.00 0.00 2,359 995.42 0.02 60.00 0.00 1,075 994.78 0.01 80.00 0.00 427 994.36 0.01 100.00 0.00 151 994.14 0.00 120.00 0.00 50 994.05 0.00 140.00 0.00 16 994.02 0.00 160.00 0.00 5 994.01 0.00 180.00 0.00 2 994.00 0.00 200.00 0.00 1 994.00 0.00 220.00 0.00 0 994.00 0.00 240.00 0.00 0 994.00 0.00 260.00 0.00 0 994.00 0.00 280.00 0.00 0 994.00 0.00 300.00 0.00 0 994.00 0.00 320.00 0.00 0 994.00 0.00 340.00 0.00 0 994.00 0.00 360.00 0.00 0 994.00 0.00 380.00 0.00 0 994.00 0.00 400.00 0.00 0 994.00 0.00 420.00 0.00 0 994.00 0.00 440.00 0.00 0 994.00 0.00 460.00 0.00 0 994.00 0.00 480.00 0.00 0 994.00 0.00 500.00 0.00 0 994.00 0.00 520.00 0.00 0 994.00 0.00 540.00 0.00 0 994.00 0.00 560.00 0.00 0 994.00 0.00 580.00 0.00 0 994.00 0.00 600.00 0.00 0 994.00 0.00 MSE 24-hr 3 100-Year Rainfall=7.38"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 44HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond 8P: West Filtration Basin Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 994.00 1,035 0 994.05 1,079 53 994.10 1,123 108 994.15 1,168 165 994.20 1,212 225 994.25 1,256 286 994.30 1,300 350 994.35 1,344 416 994.40 1,389 485 994.45 1,433 555 994.50 1,477 628 994.55 1,521 703 994.60 1,565 780 994.65 1,610 859 994.70 1,654 941 994.75 1,698 1,025 994.80 1,742 1,111 994.85 1,786 1,199 994.90 1,831 1,290 994.95 1,875 1,382 995.00 1,919 1,477 995.05 1,966 1,574 995.10 2,013 1,674 995.15 2,060 1,775 995.20 2,108 1,880 995.25 2,155 1,986 995.30 2,202 2,095 995.35 2,249 2,206 995.40 2,296 2,320 995.45 2,343 2,436 995.50 2,391 2,554 995.55 2,438 2,675 995.60 2,485 2,798 995.65 2,532 2,924 995.70 2,579 3,051 995.75 2,626 3,181 995.80 2,673 3,314 995.85 2,721 3,449 995.90 2,768 3,586 995.95 2,815 3,726 996.00 2,862 3,868 996.05 2,927 4,012 996.10 2,991 4,160 996.15 3,056 4,311 996.20 3,120 4,466 996.25 3,185 4,623 996.30 3,249 4,784 996.35 3,314 4,948 996.40 3,379 5,116 996.45 3,443 5,286 996.50 3,508 5,460 996.55 3,572 5,637 Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 996.60 3,637 5,817 996.65 3,701 6,001 996.70 3,766 6,187 996.75 3,831 6,377 996.80 3,895 6,570 996.85 3,960 6,767 996.90 4,024 6,966 996.95 4,089 7,169 997.00 4,154 7,375 997.05 4,218 7,585 997.10 4,283 7,797 997.15 4,347 8,013 997.20 4,412 8,232 997.25 4,476 8,454 997.30 4,541 8,679 997.35 4,606 8,908 997.40 4,670 9,140 997.45 4,735 9,375 997.50 4,799 9,613 997.55 4,864 9,855 997.60 4,928 10,100 997.65 4,993 10,348 997.70 5,058 10,599 997.75 5,122 10,854 997.80 5,187 11,111 997.85 5,251 11,372 997.90 5,316 11,636 997.95 5,380 11,904 998.00 5,445 12,175 998.05 5,507 12,448 998.10 5,568 12,725 998.15 5,630 13,005 998.20 5,692 13,288 998.25 5,754 13,574 998.30 5,815 13,864 998.35 5,877 14,156 998.40 5,939 14,451 998.45 6,000 14,750 998.50 6,062 15,051 MSE 24-hr 3 100-Year Rainfall=7.38"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 45HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Summary for Pond 10P: West Existing Wetland Inflow Area = 23.892 ac, 38.10% Impervious, Inflow Depth > 5.81" for 100-Year event Inflow = 22.59 cfs @ 12.10 hrs, Volume= 11.565 af Outflow = 7.20 cfs @ 13.96 hrs, Volume= 11.561 af, Atten= 68%, Lag= 111.6 min Primary = 7.20 cfs @ 13.96 hrs, Volume= 11.561 af Routed to Link 7L : TOTAL Routing by Dyn-Stor-Ind method, Time Span= 0.00-600.00 hrs, dt= 0.01 hrs Starting Elev= 974.10' Surf.Area= 54,326 sf Storage= 5,411 cf Peak Elev= 974.82' @ 13.96 hrs Surf.Area= 57,425 sf Storage= 45,373 cf (39,962 cf above start) Plug-Flow detention time= 436.6 min calculated for 11.436 af (99% of inflow) Center-of-Mass det. time= 132.0 min ( 2,784.6 - 2,652.6 ) Volume Invert Avail.Storage Storage Description #1 974.00' 487,616 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 974.00 53,893 0 0 975.00 58,226 56,060 56,060 976.00 62,886 60,556 116,616 977.00 67,093 64,990 181,605 978.00 71,582 69,338 250,943 979.00 76,083 73,833 324,775 980.00 81,311 78,697 403,472 981.00 86,977 84,144 487,616 Device Routing Invert Outlet Devices #1 Primary 974.10'18.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=7.20 cfs @ 13.96 hrs HW=974.82' TW=0.00' (Dynamic Tailwater) 1=Orifice/Grate (Orifice Controls 7.20 cfs @ 4.07 fps) MSE 24-hr 3 100-Year Rainfall=7.38"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 46HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Pond 10P: West Existing Wetland Inflow Primary Hydrograph Time (hours) 600550500450400350300250200150100500Flow (cfs)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 Inflow Area=23.892 ac Peak Elev=974.82' Storage=45,373 cf 22.59 cfs 7.20 cfs MSE 24-hr 3 100-Year Rainfall=7.38"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 47HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Hydrograph for Pond 10P: West Existing Wetland Time (hours) Inflow (cfs) Storage (cubic-feet) Elevation (feet) Primary (cfs) 0.00 0.00 5,411 974.10 0.00 20.00 3.39 29,955 974.54 4.56 40.00 1.58 17,848 974.33 1.67 60.00 0.30 10,125 974.19 0.39 80.00 0.10 7,413 974.14 0.11 100.00 0.08 7,057 974.13 0.08 120.00 0.07 6,909 974.13 0.07 140.00 0.06 6,784 974.13 0.06 160.00 0.05 6,674 974.12 0.05 180.00 0.05 6,573 974.12 0.05 200.00 0.04 6,480 974.12 0.04 220.00 0.04 6,395 974.12 0.04 240.00 0.03 6,316 974.12 0.03 260.00 0.03 6,243 974.12 0.03 280.00 0.02 6,176 974.11 0.03 300.00 0.02 6,114 974.11 0.02 320.00 0.02 6,057 974.11 0.02 340.00 0.02 6,004 974.11 0.02 360.00 0.01 5,956 974.11 0.02 380.00 0.01 5,911 974.11 0.01 400.00 0.01 5,871 974.11 0.01 420.00 0.01 5,833 974.11 0.01 440.00 0.01 5,798 974.11 0.01 460.00 0.01 5,767 974.11 0.01 480.00 0.01 5,737 974.11 0.01 500.00 0.01 5,711 974.11 0.01 520.00 0.01 5,686 974.11 0.01 540.00 0.00 5,663 974.10 0.00 560.00 0.00 5,642 974.10 0.00 580.00 0.00 5,623 974.10 0.00 600.00 0.00 5,606 974.10 0.00 MSE 24-hr 3 100-Year Rainfall=7.38"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc Page 48HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond 10P: West Existing Wetland Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 974.00 53,893 0 974.10 54,326 5,411 974.20 54,760 10,865 974.30 55,193 16,363 974.40 55,626 21,904 974.50 56,060 27,488 974.60 56,493 33,116 974.70 56,926 38,787 974.80 57,359 44,501 974.90 57,793 50,259 975.00 58,226 56,060 975.10 58,692 61,905 975.20 59,158 67,798 975.30 59,624 73,737 975.40 60,090 79,723 975.50 60,556 85,755 975.60 61,022 91,834 975.70 61,488 97,959 975.80 61,954 104,131 975.90 62,420 110,350 976.00 62,886 116,616 976.10 63,307 122,925 976.20 63,727 129,277 976.30 64,148 135,671 976.40 64,569 142,106 976.50 64,990 148,584 976.60 65,410 155,104 976.70 65,831 161,666 976.80 66,252 168,271 976.90 66,672 174,917 977.00 67,093 181,605 977.10 67,542 188,337 977.20 67,991 195,113 977.30 68,440 201,935 977.40 68,889 208,801 977.50 69,338 215,713 977.60 69,786 222,669 977.70 70,235 229,670 977.80 70,684 236,716 977.90 71,133 243,807 978.00 71,582 250,943 978.10 72,032 258,123 978.20 72,482 265,349 978.30 72,932 272,620 978.40 73,382 279,935 978.50 73,833 287,296 978.60 74,283 294,702 978.70 74,733 302,153 978.80 75,183 309,648 978.90 75,633 317,189 979.00 76,083 324,775 979.10 76,606 332,409 Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 979.20 77,129 340,096 979.30 77,651 347,835 979.40 78,174 355,626 979.50 78,697 363,470 979.60 79,220 371,366 979.70 79,743 379,314 979.80 80,265 387,314 979.90 80,788 395,367 980.00 81,311 403,472 980.10 81,878 411,631 980.20 82,444 419,848 980.30 83,011 428,120 980.40 83,577 436,450 980.50 84,144 444,836 980.60 84,711 453,278 980.70 85,277 461,778 980.80 85,844 470,334 980.90 86,410 478,947 981.00 86,977 487,616 Project Information Calculator Version: Version 4: July 2020 Project Name:Pleasant View Pointe -Entire SWM Drainage Area User Name / Company Name: Alliant Engineering Date: 4-18-25 Project Description: Construction Permit?:No Site Information Retention Requirement (inches):1 Site's Zip Code: 55317 Annual Rainfall (inches): 29.9 Phosphorus EMC (mg/l): 0.3 TSS EMC (mg/l):54.5 Total Site Area Land Cover A Soils (acres) B Soils (acres) C Soils (acres) D Soils (acres) Total (acres) Forest/Open Space -Undisturbed, protected forest/open space or reforested land 3.640 3.64 Managed Turf -disturbed, graded for yards or other turf to be mowed/managed 12.438 12.438 Impervious Area (acres) 8.056 Total Area (acres) 24.134 Site Areas Routed to BMPs Land Cover A Soils (acres) B Soils (acres) C Soils (acres) D Soils (acres) Total (acres) Forest/Open Space -Undisturbed, protected forest/open space or reforested land 3.64 3.64 Managed Turf -disturbed, graded for yards or other turf to be mowed/managed 12.438 12.438 Impervious Area (acres) 8.056 Total Area (acres) 24.134 Summary Information Performance Goal Requirement Performance goal volume retention requirement: 29243 ft3 Volume removed by BMPs towards performance goal: 10615 ft³ Percent volume removed towards performance goal 36 % Annual Volume and Pollutant Load Reductions Post development annual runoff volume 24.5435 acre-ft Annual runoff volume removed by BMPs: 4.9689 acre-ft Percent annual runoff volume removed: 20 % Post development annual particulate P load:11.0151 lbs Annual particulate P removed by BMPs: 10.114 lbs Post development annual dissolved P load: 9.012 lbs Annual dissolved P removed by BMPs: 2.493 lbs Total P removed by BMPs 12.607 lbs Percent annual total phosphorus removed: 63 % Post development annual TSS load: 3638.3 lbs Annual TSS removed by BMPs:3456.3 lbs Percent annual TSS removed: 95 % BMP Summary Performance Goal Summary BMP Name BMP Volume Capacity (ft3) Volume Recieved (ft3) Volume Retained (ft3) Volume Outflow (ft3) Percent Retained (%) BMP 1 7949 25578 7949 17629 31 West Filtration Basin 545 1544 545 999 35 1 -Stormwater disconnection (Impervious disconnection)1186 2686 1186 1500 44 Dissconnected - Untreated 0 0 0 0 0 West Disconnected Impervious S4 935 2479 935 1544 38 1 - Constructed wetland 0 25578 0 25578 0 Annual Volume Summary BMP Name Volume From Direct Watershed (acre-ft) Volume From Upstream BMPs (acre-ft) Volume Retained (acre-ft) Volume outflow (acre-ft) Percent Retained (%) BMP 1 0 22.0838 4.0506 18.0332 18 West Filtration Basin 0 1.7737 0.3088 1.4649 17 1 -Stormwater disconnection (Impervious disconnection)3.0645 0 0.3566 2.7079 12 Dissconnected - Untreated 0.0765 0 0 0.0765 0 West Disconnected Impervious S4 2.0265 0 0.2528 1.7737 12 1 - Constructed wetland 19.376 2.7078 0 22.0838 0 Particulate Phosphorus Summary BMP Name Load From Direct Watershed (lbs) Load From Upstream BMPs (lbs) Load Retained (lbs) Outflow Load (lbs) Percent Retained (%) BMP 1 0 4.505 3.7693 0.7357 84 West Filtration Basin 0 0.796 0.6645 0.1315 83 1 -Stormwater disconnection (Impervious disconnection)1.3753 0 0.1601 1.2152 12 Dissconnected - Untreated 0.0343 0 0 0.0343 0 West Disconnected Impervious S4 0.9095 0 0.1135 0.796 12 1 - Constructed wetland 8.6959 1.2152 5.4061 4.505 55 Dissolved Phosphorus Summary BMP Name Load From Direct Watershed (lbs) Load From Upstream BMPs (lbs) Load Retained (lbs) Outflow Load (lbs) Percent Retained (%) BMP 1 0 8.1092 2.1052 6.004 26 West Filtration Basin 0 0.6513 0.1636 0.4877 25 1 -Stormwater disconnection (Impervious disconnection)1.1253 0 0.131 0.9943 12 Dissconnected - Untreated 0.0281 0 0 0.0281 0 West Disconnected Impervious S4 0.7441 0 0.0928 0.6513 12 1 - Constructed wetland 7.1149 0.9943 0 8.1092 0 Total Phosphorus Summary BMP Name Load From Direct Watershed (lbs) Load From Upstream BMPs (lbs) Load Retained (lbs) Outflow Load (lbs) Percent Retained (%) BMP 1 0 12.6142 5.8745 6.7397 55 West Filtration Basin 0 1.4473 0.8281 0.6192 54 1 -Stormwater disconnection (Impervious disconnection)2.5006 0 0.2911 2.2095 12 Dissconnected - Untreated 0.0624 0 0 0.0624 0 West Disconnected Impervious S4 1.6536 0 0.2063 1.4473 12 1 - Constructed wetland 15.8108 2.2095 5.4061 12.6142 28 TSS Summary BMP Name Load From Direct Watershed (lbs) Load From Upstream BMPs (lbs) Load Retained (lbs) Outflow Load (lbs) Percent Retained (%) BMP 1 0 960.24 803.42 156.82 84 West Filtration Basin 0 84.14 70.24 13.9 83 1 -Stormwater disconnection (Impervious disconnection)454.28 0 325.83 128.45 72 Dissconnected - Untreated 11.34 0 0 11.34 0 West Disconnected Impervious S4 300.42 0 216.28 84.14 72 1 - Constructed wetland 2872.3 128.45 2040.51 960.24 68 BMP Schematic Project Information Calculator Version: Version 4: July 2020 Project Name:Pleasant View Pointe -Project Site + Pleasant View Dr. User Name / Company Name: Alliant Engineering Date: 4-18-25 Project Description: Construction Permit?:No Site Information Retention Requirement (inches):1 Site's Zip Code: 55317 Annual Rainfall (inches): 29.9 Phosphorus EMC (mg/l): 0.3 TSS EMC (mg/l):54.5 Total Site Area Land Cover A Soils (acres) B Soils (acres) C Soils (acres) D Soils (acres) Total (acres) Forest/Open Space -Undisturbed, protected forest/open space or reforested land 3.641 3.641 Managed Turf -disturbed, graded for yards or other turf to be mowed/managed 6.447 6.447 Impervious Area (acres) 5.802 Total Area (acres) 15.89 Site Areas Routed to BMPs Land Cover A Soils (acres) B Soils (acres) C Soils (acres) D Soils (acres) Total (acres) Forest/Open Space -Undisturbed, protected forest/open space or reforested land 3.641 3.641 Managed Turf -disturbed, graded for yards or other turf to be mowed/managed 6.447 6.447 Impervious Area (acres) 5.802 Total Area (acres) 15.89 Summary Information Performance Goal Requirement Performance goal volume retention requirement: 21061 ft3 Volume removed by BMPs towards performance goal: 10615 ft³ Percent volume removed towards performance goal 50 % Annual Volume and Pollutant Load Reductions Post development annual runoff volume 16.383 acre-ft Annual runoff volume removed by BMPs: 4.247 acre-ft Percent annual runoff volume removed: 26 % Post development annual particulate P load:7.3527 lbs Annual particulate P removed by BMPs: 6.754 lbs Post development annual dissolved P load: 6.016 lbs Annual dissolved P removed by BMPs: 1.973 lbs Total P removed by BMPs 8.727 lbs Percent annual total phosphorus removed: 65 % Post development annual TSS load: 2428.6 lbs Annual TSS removed by BMPs:2316.2 lbs Percent annual TSS removed: 95 % BMP Summary Performance Goal Summary BMP Name BMP Volume Capacity (ft3) Volume Recieved (ft3) Volume Retained (ft3) Volume Outflow (ft3) Percent Retained (%) BMP 1 7949 17396 7949 9447 46 West Filtration Basin 545 1544 545 999 35 1 -Stormwater disconnection (Impervious disconnection)1186 2686 1186 1500 44 Dissconnected - Untreated 0 0 0 0 0 West Disconnected Impervious S4 935 2479 935 1544 38 1 - Constructed wetland 0 17396 0 17396 0 Annual Volume Summary BMP Name Volume From Direct Watershed (acre-ft) Volume From Upstream BMPs (acre-ft) Volume Retained (acre-ft) Volume outflow (acre-ft) Percent Retained (%) BMP 1 0 13.9234 3.3287 10.5947 24 West Filtration Basin 0 1.7737 0.3088 1.4649 17 1 -Stormwater disconnection (Impervious disconnection)3.0645 0 0.3566 2.7079 12 Dissconnected - Untreated 0.0765 0 0 0.0765 0 West Disconnected Impervious S4 2.0265 0 0.2528 1.7737 12 1 - Constructed wetland 11.2155 2.7078 0 13.9233 0 Particulate Phosphorus Summary BMP Name Load From Direct Watershed (lbs) Load From Upstream BMPs (lbs) Load Retained (lbs) Outflow Load (lbs) Percent Retained (%) BMP 1 0 2.8403 2.408 0.4323 85 West Filtration Basin 0 0.796 0.6645 0.1315 83 1 -Stormwater disconnection (Impervious disconnection)1.3753 0 0.1601 1.2152 12 Dissconnected - Untreated 0.0343 0 0 0.0343 0 West Disconnected Impervious S4 0.9095 0 0.1135 0.796 12 1 - Constructed wetland 5.0335 1.2152 3.4084 2.8403 55 Dissolved Phosphorus Summary BMP Name Load From Direct Watershed (lbs) Load From Upstream BMPs (lbs) Load Retained (lbs) Outflow Load (lbs) Percent Retained (%) BMP 1 0 5.1126 1.5853 3.5273 31 West Filtration Basin 0 0.6513 0.1636 0.4877 25 1 -Stormwater disconnection (Impervious disconnection)1.1253 0 0.131 0.9943 12 Dissconnected - Untreated 0.0281 0 0 0.0281 0 West Disconnected Impervious S4 0.7441 0 0.0928 0.6513 12 1 - Constructed wetland 4.1183 0.9943 0 5.1126 0 Total Phosphorus Summary BMP Name Load From Direct Watershed (lbs) Load From Upstream BMPs (lbs) Load Retained (lbs) Outflow Load (lbs) Percent Retained (%) BMP 1 0 7.9529 3.9933 3.9596 58 West Filtration Basin 0 1.4473 0.8281 0.6192 54 1 -Stormwater disconnection (Impervious disconnection)2.5006 0 0.2911 2.2095 12 Dissconnected - Untreated 0.0624 0 0 0.0624 0 West Disconnected Impervious S4 1.6536 0 0.2063 1.4473 12 1 - Constructed wetland 9.1518 2.2095 3.4084 7.9529 28 TSS Summary BMP Name Load From Direct Watershed (lbs) Load From Upstream BMPs (lbs) Load Retained (lbs) Outflow Load (lbs) Percent Retained (%) BMP 1 0 573.13 485.91 87.2199999999999 85 West Filtration Basin 0 84.14 70.24 13.9 83 1 -Stormwater disconnection (Impervious disconnection)454.28 0 325.83 128.45 72 Dissconnected - Untreated 11.34 0 0 11.34 0 West Disconnected Impervious S4 300.42 0 216.28 84.14 72 1 - Constructed wetland 1662.59 128.45 1217.91 573.13 68 BMP Schematic Project Information Calculator Version: Version 4: July 2020 Project Name:Pleasant View Pointe -Troendle Addition User Name / Company Name: Alliant Engineering Date: 4-18-2025 Project Description: Construction Permit?:No Site Information Retention Requirement (inches):1 Site's Zip Code: 55317 Annual Rainfall (inches): 29.9 Phosphorus EMC (mg/l): 0.3 TSS EMC (mg/l):54.5 Total Site Area Land Cover A Soils (acres) B Soils (acres) C Soils (acres) D Soils (acres) Total (acres) Forest/Open Space -Undisturbed, protected forest/open space or reforested land 3.640 3.64 Managed Turf -disturbed, graded for yards or other turf to be mowed/managed 8.489 8.489 Impervious Area (acres) 7.405 Total Area (acres) 19.534 Site Areas Routed to BMPs Land Cover A Soils (acres) B Soils (acres) C Soils (acres) D Soils (acres) Total (acres) Forest/Open Space -Undisturbed, protected forest/open space or reforested land 3.64 3.64 Managed Turf -disturbed, graded for yards or other turf to be mowed/managed 8.489 8.489 Impervious Area (acres) 7.405 Total Area (acres) 19.534 Summary Information Performance Goal Requirement Performance goal volume retention requirement: 26880 ft3 Volume removed by BMPs towards performance goal: 10615 ft³ Percent volume removed towards performance goal 39 % Annual Volume and Pollutant Load Reductions Post development annual runoff volume 20.9427 acre-ft Annual runoff volume removed by BMPs: 4.6417 acre-ft Percent annual runoff volume removed: 22 % Post development annual particulate P load:9.3991 lbs Annual particulate P removed by BMPs: 8.631 lbs Post development annual dissolved P load: 7.69 lbs Annual dissolved P removed by BMPs: 2.26 lbs Total P removed by BMPs 10.891 lbs Percent annual total phosphorus removed: 64 % Post development annual TSS load: 3104.6 lbs Annual TSS removed by BMPs:2953.2 lbs Percent annual TSS removed: 95 % BMP Summary Performance Goal Summary BMP Name BMP Volume Capacity (ft3) Volume Recieved (ft3) Volume Retained (ft3) Volume Outflow (ft3) Percent Retained (%) BMP 1 7949 23215 7949 15266 34 West Filtration Basin 545 1544 545 999 35 1 -Stormwater disconnection (Impervious disconnection)1186 2686 1186 1500 44 Dissconnected - Untreated 0 0 0 0 0 West Disconnected Impervious S4 935 2479 935 1544 38 1 - Constructed wetland 0 23215 0 23215 0 Annual Volume Summary BMP Name Volume From Direct Watershed (acre-ft) Volume From Upstream BMPs (acre-ft) Volume Retained (acre-ft) Volume outflow (acre-ft) Percent Retained (%) BMP 1 0 18.4831 3.7234 14.7597 20 West Filtration Basin 0 1.7737 0.3088 1.4649 17 1 -Stormwater disconnection (Impervious disconnection)3.0645 0 0.3566 2.7079 12 Dissconnected - Untreated 0.0765 0 0 0.0765 0 West Disconnected Impervious S4 2.0265 0 0.2528 1.7737 12 1 - Constructed wetland 15.7752 2.7078 0 18.483 0 Particulate Phosphorus Summary BMP Name Load From Direct Watershed (lbs) Load From Upstream BMPs (lbs) Load Retained (lbs) Outflow Load (lbs) Percent Retained (%) BMP 1 0 3.7705 3.1683 0.6022 84 West Filtration Basin 0 0.796 0.6645 0.1315 83 1 -Stormwater disconnection (Impervious disconnection)1.3753 0 0.1601 1.2152 12 Dissconnected - Untreated 0.0343 0 0 0.0343 0 West Disconnected Impervious S4 0.9095 0 0.1135 0.796 12 1 - Constructed wetland 7.0799 1.2152 4.5246 3.7705 55 Dissolved Phosphorus Summary BMP Name Load From Direct Watershed (lbs) Load From Upstream BMPs (lbs) Load Retained (lbs) Outflow Load (lbs) Percent Retained (%) BMP 1 0 6.787 1.8729 4.9141 28 West Filtration Basin 0 0.6513 0.1636 0.4877 25 1 -Stormwater disconnection (Impervious disconnection)1.1253 0 0.131 0.9943 12 Dissconnected - Untreated 0.0281 0 0 0.0281 0 West Disconnected Impervious S4 0.7441 0 0.0928 0.6513 12 1 - Constructed wetland 5.7927 0.9943 0 6.787 0 Total Phosphorus Summary BMP Name Load From Direct Watershed (lbs) Load From Upstream BMPs (lbs) Load Retained (lbs) Outflow Load (lbs) Percent Retained (%) BMP 1 0 10.5575 5.0412 5.5163 56 West Filtration Basin 0 1.4473 0.8281 0.6192 54 1 -Stormwater disconnection (Impervious disconnection)2.5006 0 0.2911 2.2095 12 Dissconnected - Untreated 0.0624 0 0 0.0624 0 West Disconnected Impervious S4 1.6536 0 0.2063 1.4473 12 1 - Constructed wetland 12.8726 2.2095 4.5246 10.5575 28 TSS Summary BMP Name Load From Direct Watershed (lbs) Load From Upstream BMPs (lbs) Load Retained (lbs) Outflow Load (lbs) Percent Retained (%) BMP 1 0 789.43 663.35 126.08 84 West Filtration Basin 0 84.14 70.24 13.9 83 1 -Stormwater disconnection (Impervious disconnection)454.28 0 325.83 128.45 72 Dissconnected - Untreated 11.34 0 0 11.34 0 West Disconnected Impervious S4 300.42 0 216.28 84.14 72 1 - Constructed wetland 2338.52 128.45 1677.54 789.43 68 BMP Schematic MSE 24-hr 3 100-Year Rainfall=7.38"PDRN Printed 4/18/2025Prepared by Alliant Engineering, Inc HydroCAD® 10.20-5c s/n 01427 © 2023 HydroCAD Software Solutions LLC Stage-Area-Storage for Pond 1P: FILTRATION/POND Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 989.00 4,873 0 989.20 5,086 996 989.40 5,299 2,034 989.60 5,513 3,116 989.80 5,726 4,240 990.00 9,960 5,406 990.20 10,653 7,467 990.40 11,347 9,667 990.60 12,040 12,006 990.80 12,733 14,483 991.00 13,427 17,099 991.20 14,161 19,858 991.40 14,896 22,764 991.60 15,630 25,816 991.80 16,365 29,016 992.00 17,100 32,362 992.20 17,874 35,860 992.40 18,649 39,512 992.60 19,424 43,319 992.80 20,199 47,282 993.00 20,974 51,701 993.20 22,520 56,653 993.40 24,067 61,916 993.60 29,318 67,836 993.80 31,729 74,544 994.00 79,538 81,734 994.20 80,436 90,904 994.40 81,334 100,253 994.60 82,232 109,781 994.80 83,130 119,490 995.00 84,028 129,377 995.20 84,688 139,421 995.40 85,348 149,597 995.60 86,008 159,904 995.80 86,668 170,344 996.00 87,328 180,915 996.20 87,682 191,588 996.40 88,036 202,332 996.60 88,390 213,147 996.80 88,744 224,032 997.00 89,099 234,989 997.20 89,453 246,016 997.40 89,807 257,114 997.60 90,161 268,282 997.80 90,515 279,522 998.00 90,869 290,832 998.20 92,237 302,315 998.40 93,604 314,071 998.60 94,972 326,101 998.80 96,339 338,404 999.00 97,707 350,980 999.20 99,075 363,831 Elevation (feet) Surface (sq-ft) Storage (cubic-feet) 999.40 100,442 376,954 999.60 101,810 390,351 999.80 103,177 404,022 1,000.00 104,545 417,966 IMP RUNOFFINTENSITYP. DIA. P. SLOPEP. TYPEMANNING'SP. CAP. P. VELOCITY PIPE CAP. OVER FROM TO RIM COVER STR. CAST BUILDFROM TO TOTALIMPERVIOUSINCR. CUM. % C INCR. CUM. PIPE CUM. i INCR. CUM. D [IN] S [FT/FT] n Q [CFS] MAX [FT/S] LENGTH [FT] Q [CFS] INVERT INVERT ELEV [FT] TYPE TYPE[FT]PE 103 OCS 102 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 12.000 0.004 RCP 0.013 2.363 3.009 22.900 2.363 991.000 993.000 0.000 0.000 0 0 0OCS 102 MH 101 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 12.000 0.004 RCP 0.013 2.363 3.009 173.000 2.363 991.104 990.343 1000.000 7.696 60" OCS 8.89584MH 101 FES 100 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 12.000 0.004 RCP 0.013 2.363 3.009 73.400 2.363 990.343 990.020 1000.430 8.887 48" R-1642 10.08704FES 100 OFFSITE 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 12.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 15" FES 00 0 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0 0 0EXMH 1 EXMH 3 111200.000 56544.000 2.553 2.553 0.508 0.556 1.419 1.419 15.000 15.000 4.402 6.247 6.247 15.000 0.017 RCP 0.013 8.398 6.843 159.100 2.150 1009.170 1006.481 1017.000 6.380 27 R-4342 7.83CBMH2 EXMH3 33064.000 7777.000 0.759 0.759 0.235 0.365 0.277 0.277 12.000 12.000 4.752 1.315 1.315 12.000 0.018 RCP 0.013 4.793 6.103 26.800 3.478 1006.970 1006.485 1010.670 2.500 2'x3' R-3067-V 3.7EXMH 3 CBMH 202 0.000 0.000 0.000 3.312 0.000 0.200 0.000 1.696 0.387 15.387 4.362 0.000 7.398 15.000 0.025 RCP 0.013 10.214 8.323 41.200 2.816 1006.481 1005.451 1010.770 2.839 48" R-1642 10.57CB 213 MH 212 51000.000 11674.500 1.171 1.171 0.229 0.360 0.422 0.422 12.000 12.000 4.752 2.004 2.004 12.000 0.004 RCP 0.013 2.363 3.009 170.940 0.359 1013.800 1013.048 1017.000 2.000 27 R-4342 3.2MH 212 CBMH 209 0.000 0.000 0.000 0.000 0.000 0.200 0.000 0.422 0.947 12.947 4.633 0.000 1.954 12.000 0.005 RCP 0.013 2.519 3.208 275.460 0.565 1013.048 1011.671 1032.420 18.172 48" R-1642 19.372136CB 211 CBMH 209 36460.000 15686.400 0.837 0.837 0.430 0.501 0.419 0.419 10.000 10.000 5.037 2.113 2.113 12.000 0.005 RCP 0.013 2.519 3.208 31.000 0.406 1020.320 1020.165 1024.320 2.800 2'x3' R-3067-V 4CB 210 CBMH 209 41622.000 12486.600 0.956 1.793 0.300 0.410 0.392 0.392 10.000 10.000 5.037 1.973 1.973 12.000 0.004 RCP 0.013 2.374 3.023 163.640 0.401 1012.400 1011.673 1015.600 2.000 27" R-4342 3.2CBMH 209 CBMH 208 34797.000 15008.700 0.799 3.428 0.431 0.502 0.401 1.634 1.431 14.378 4.468 1.792 7.301 15.000 0.025 RCP 0.013 10.214 8.323 205.250 2.913 1011.671 1006.539 1024.320 11.199 48" R-3067-V 12.649436CBMH 208 MH 206 16308.000 6826.700 0.374 1.545 0.419 0.493 0.185 1.819 0.411 14.789 4.424 0.817 8.046 15.000 0.040 RCP 0.013 12.871 10.488 41.390 4.825 1006.539 1004.896 1010.580 2.591 48" R-3067-V 4.040686CB 207 MH 206 19168.000 7715.500 0.440 0.440 0.403 0.482 0.212 0.212 10.000 10.000 5.037 1.068 1.068 12.000 0.005 RCP 0.013 2.416 3.077 47.120 1.349 1005.120 1004.903 1008.820 2.500 2'x3' R-3067-V 3.7MH 206 CBMH 204 0.000 0.000 0.000 1.985 0.000 0.200 0.000 2.031 0.066 14.855 4.417 0.000 8.970 18.000 0.008 RCP 0.013 9.097 5.148 72.390 0.128 1004.903 1004.360 1009.460 2.857 48" R-1642 4.556752CB 205 CBMH 204 10199.000 4979.100 0.234 0.234 0.488 0.542 0.127 0.127 10.000 10.000 5.037 0.639 0.639 12.000 0.012 RCP 0.013 3.919 4.990 31.000 3.280 1004.740 1004.365 1008.740 2.800 2'x3' R-3067-V 4CBMH 204 CBMH 202 16305.000 6084.500 0.374 2.594 0.373 0.461 0.173 2.330 0.234 15.089 4.393 0.758 10.235 18.000 0.010 RCP 0.013 10.504 5.944 89.120 0.269 1004.360 1003.469 1008.740 2.680 48" R-3067-V 4.379677CB203 CBMH 202 17905.000 5371.500 0.411 0.411 0.300 0.410 0.169 0.169 10.000 10.000 5.037 0.849 0.849 12.000 0.010 RCP 0.013 3.563 4.536 94.700 2.714 1005.700 1004.753 1008.900 2.000 27" R-4342 3.2CBMH 202 CBMH 201 31951.000 10017.250 0.733 7.050 0.314 0.419 0.308 4.502 0.083 15.470 4.354 1.340 19.601 18.000 0.050 RCP 0.013 23.559 13.332 148.550 3.957 1003.469 995.997 1009.500 4.331 48" R-3067-V 10.030877CBMH 201 FES 200 0.000 0.000 0.000 7.050 0.000 0.200 0.000 4.502 0.186 15.656 4.335 0.000 19.517 27.000 0.004 RCP 0.013 19.587 4.926 46.700 0.070 994.190 994.003 1000.000 3.360 48" R-4342 5.81FES 200 POND 0.000 0.000 9.641 0.000 0.000 0.000 4.502 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 994.000 0.000 0.000 27 FES 00 0 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0 0 0CB 302 CBMH 301 23682.000 11890.750 0.544 0.544 0.502 0.551 0.300 0.300 10.000 10.000 5.037 1.510 1.510 12.000 0.008 RCP 0.013 3.187 4.057 31.000 1.676 995.240 994.992 999.240 2.800 2'x3' R-3067-V 4CBMH 301 FES 300 18066.000 7761.500 0.415 0.958 0.430 0.501 0.208 0.507 0.127 10.127 5.018 1.042 2.546 15.000 0.005 RCP 0.013 4.568 3.722 45.500 2.021 994.230 994.003 999.240 3.048 48" R-3067-V 9.01FES 300 POND 0.000 0.000 0.958 0.000 0.000 0.000 0.507 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 994.000 0.000 0.000 15" FES 00 0 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0 0 0CBMH 401 FES 400 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 12.000 0.004 RCP 0.013 0.000 0.000 27.210 0.000 994.120 994.000 997.800 2.480 48" R-4342 7.6802760 0 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 994.000 0.000 0.000 0 0 00 0 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0 0 0PE 502 OCS 501 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 18.000 0.000 RCP 0.013 0.000 0.000 9.200 0.000 994.000 994.000 998.200 0.000 60" OCS 5.78OCS 501 Ex. PE 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 18.000 0.088 CMP 0.021 0.000 0.000 32.800 0.000 992.420 989.520 0.000 0.000 0 0 0Q [CFS]MH/CB AREA [SF] AREA [AC] A*CTIME OF CONC. [MIN] Geotechnical Evaluation Report Pleasant View Pointe Development 6535 Peaceful Lane Chanhassen, Minnesota Prepared for Rachel Development , Inc. Professional Certification: I hereby certify that this plan, specification, or report was prepared by me or under my direct supervision and that I am a duly Licensed Professional Engineer under the laws of the State of Minnesota. John T. Carlson, PE Senior Engineer License Number: 20663 February 17, 2025 Project B2405314 Braun Intertec Corporation AA/EOE Braun Intertec Corporation 11001 Hampshire Avenue S Minneapolis, MN 55438 Phone: 952.995.2000 Fax: 952.995.2020 Web: braunintertec.com February 17, 2025 Project B2405314 Mr. Paul Robinson Rachel Development, Inc. 4180 Napier Court NE St. Michael, MN 55446 Re: Geotechnical Evaluation Pleasant View Pointe Development 6535 Peaceful Lane Chanhassen, Minnesota Dear Mr. Robinson: We are pleased to present this Geotechnical Evaluation Report for the proposed Pleasant View Pointe residential development in Chanhassen, Minnesota. Please read the entire attached report for details regarding our findings and recommendations. Thank you for making Braun Intertec Corporation your geotechnical consultant for this project. If you have questions about this report, or if there are other services that we can provide in support of our work to date, please contact John Carlson at 952.540.7248 (johcarlson@braunintertec.com). Sincerely, BRAUN INTERTEC CORPORATION Henry Vloo, PE Senior Engineer John T. Carlson, PE Senior Engineer Cc: Steve Wolbeck; Rachel Development, LLC Mark Rausch, PE; Alliant Engineering, Inc. Joe Westphal, PE; Braun Intertec Corporation Table of Contents Description Page A. Introduction ...................................................................................................................................... 1 A.1. Project Description .............................................................................................................. 1 A.1.a. Structural Loads ...................................................................................................... 2 A.1.b. Pavement Traffic Loads .......................................................................................... 2 A.2. Site Conditions and History ................................................................................................. 2 A.3. Purpose ................................................................................................................................ 3 A.4. Background Information and Reference Documents .......................................................... 3 A.5. Scope of Services ................................................................................................................. 4 B. Results .............................................................................................................................................. 5 B.1. Geologic Overview .............................................................................................................. 5 B.2. Boring Results ...................................................................................................................... 5 B.3. Groundwater ....................................................................................................................... 6 B.4. Laboratory Test Results ....................................................................................................... 6 C. Recommendations ........................................................................................................................... 6 C.1. Design and Construction Discussion ................................................................................... 6 C.1.a. Building Subgrade Preparation .............................................................................. 6 C.1.b. Reuse of On-Site Soils ............................................................................................. 7 C.1.c. Disturbance of On-Site Soils ................................................................................... 7 C.1.d. Effects of Groundwater .......................................................................................... 7 C.2. Site Grading and Subgrade Preparation .............................................................................. 7 C.2.a. Building Subgrade Excavations ............................................................................... 7 C.2.b. Excavation Oversizing ............................................................................................. 9 C.2.c. Excavated Slopes .................................................................................................... 9 C.2.d. Filling on Slopes .................................................................................................... 10 C.2.e. Excavation Dewatering ......................................................................................... 10 C.2.f. Selecting Excavation Backfill and Additional Required Fill ................................... 10 C.2.g. Pavement and Exterior Slab Subgrade Preparation ............................................. 10 C.2.h. Pavement Subgrade Proofroll .............................................................................. 11 C.2.i. Engineered Fill Materials and Compaction Requirements ................................... 11 C.3. Spread Footings ................................................................................................................. 13 C.3.a. Embedment Depth ............................................................................................... 13 C.3.b. Subgrade Improvement ....................................................................................... 13 C.3.c. Net Allowable Bearing Pressure ........................................................................... 14 C.3.d. Settlement ............................................................................................................ 14 C.4. Basement Walls ................................................................................................................. 14 C.4.a. Drainage Control .................................................................................................. 14 C.4.b. Selection, Placement and Compaction of Backfill ................................................ 16 C.4.c. Configuring and Resisting Lateral Loads............................................................... 17 C.5. Interior Slabs ..................................................................................................................... 17 C.5.a. Moisture Vapor Protection .................................................................................. 17 C.5.b. Radon ................................................................................................................... 18 C.6. Frost Protection ................................................................................................................. 18 C.6.a. General ................................................................................................................. 18 C.6.b. Frost Heave Mitigation ......................................................................................... 18 C.7. Pavements ......................................................................................................................... 20 Table of Contents (continued) Description Page C.7.a. Design Sections .................................................................................................... 20 C.7.b. Bituminous Pavement Materials .......................................................................... 20 C.7.c. Subgrade Drainage ............................................................................................... 20 C.7.d. Performance and Maintenance ........................................................................... 20 C.8. Utilities .............................................................................................................................. 21 C.8.a. Subgrade Stabilization .......................................................................................... 21 C.8.b. Selection, Placement, and Compaction of Backfill ............................................... 21 C.8.c. Corrosion Potential .............................................................................................. 21 C.9. Stormwater........................................................................................................................ 21 D. Procedures...................................................................................................................................... 22 D.1. Penetration Test Borings ................................................................................................... 22 D.2. Exploration Logs ................................................................................................................ 22 D.2.a. Log of Boring Sheets ............................................................................................. 22 D.2.b. Log of Test Pit Sheets ........................................................................................... 22 D.2.c. Geologic Origins ................................................................................................... 22 D.3. Material Classification and Testing ................................................................................... 23 D.3.a. Visual and Manual Classification .......................................................................... 23 D.3.b. Laboratory Testing ............................................................................................... 23 D.4. Groundwater Measurements ............................................................................................ 23 E. Qualifications .................................................................................................................................. 23 E.1. Variations in Subsurface Conditions .................................................................................. 23 E.1.a. Material Strata ..................................................................................................... 23 E.1.b. Groundwater Levels ............................................................................................. 24 E.2. Continuity of Professional Responsibility .......................................................................... 24 E.2.a. Plan Review .......................................................................................................... 24 E.2.b. Construction Observations and Testing ............................................................... 24 E.3. Use of Report..................................................................................................................... 24 E.4. Standard of Care ................................................................................................................ 24 Appendix Soil Boring Location Sketch Log of Boring Sheets ST-1 through ST-8 Log of Test Pit Sheets TP-1 through TP-8 Descriptive Terminology of Soil A. Introduction A.1. Project Description Rachel Development, Inc. (Rachel) is planning to develop a new residential housing development on the four parcels of land known as the Beddor Properties. One of the properties has an address of 6535 Peaceful Lane in Chanhassen, Minnesota. Concept plans indicate that the proposed development will likely consist of construction of 19 single-family building pads along with construction of associated streets, underground utilities, and stormwater features/ponds. Figure 1 shows the proposed site development plan dated May 1, 2024 prepared by Alliant Engineering. Figure 1. Beddor Property – Initial Concept Plan Concept site plan prepared by Alliant Engineering. Rachel Development, Inc. Project B2405314 February 17, 2025 Page 2 A.1.a. Structural Loads Construction will likely consist of one- to two-story wood-framed houses with pitched roofs. The homes will likely be constructed with full-depth basements with wood framing above grade. A.1.b. Pavement Traffic Loads We have assumed that bituminous pavements, typical of residential neighborhoods, will be subjected to normal traffic conditions over a design life of 20 years. A.2. Site Conditions and History The site consists of four parcels of land totaling about 13 1/4 acres of mostly open property. There is a home on one of the properties. There are scattered wooded areas on this site as well as a pond in the north parcel. Just off the southwest corner of the site is a City of Chanhassen water storage facility. The site generally slopes down to the northwest, with the highest elevations of about 1025 Mean Sea Level (MSL) near the water storage facility in the southwest part of the site down to the low area of the site at about 925 MSL near the existing pond in the northwest part of the site. Figure 2 shows an aerial photograph showing the current site conditions, as obtained from the Carver County GIS site using 2022 aerial imagery. Rachel Development, Inc. Project B2405314 February 17, 2025 Page 3 Figure 2. Aerial Photograph of the Site - 2022 Photograph obtained from Carver County GIS. A.3. Purpose The purpose of our geotechnical evaluation will be to characterize subsurface geologic conditions at selected exploration locations and evaluate their impact on the design and construction of the proposed residential development. A.4. Background Information and Reference Documents We reviewed the following information: ▪ Site information provided to us by Rachel. ▪ Concept plan dated May 1, 2024 prepared by Alliant Engineering. ▪ Available public aerial photographs showing the existing site conditions. ▪ Geologic atlas showing the general soil types present in this area. Rachel Development, Inc. Project B2405314 February 17, 2025 Page 4 We have described our understanding of the proposed construction and site to the extent others reported it to us. Depending on the extent of available information, we may have made assumptions based on our experience with similar projects. If we have not correctly recorded or interpreted the project details, the project team should notify us. New or changed information could require additional evaluation, analyses and/or recommendations. A.5. Scope of Services We completed our services based on the Proposal for Geotechnical Evaluation QTB197503 to Rachel Development, Inc. dated May 29, 2024. The following list describes the geotechnical tasks completed in accordance with our authorized scope of services. ▪ Reviewing the background information and reference documents previously cited. ▪ Coordinating the clearing of the exploration locations of public underground utilities. The soil boring locations were chosen and staked in the field by Braun Intertec. The existing ground surface elevations at the borings were obtained by Braun Intertec personnel using a GPS locating system. ▪ Performing eight standard penetration test (SPT) borings, denoted as ST-1 to ST-8, to nominal depths of 15 to 20 feet below grade across the site. ▪ Performing laboratory testing on select samples to aid in soil classification and engineering analysis. ▪ After the borings were completed, we were requested to observe backhoe test pits to further evaluate the soil conditions. A total of eight test pits were observed by Braun Intertec on January 8, 2025. Alliant Engineering provided the surface elevations at the test pit locations. ▪ Preparing this report containing a boring location sketch, logs of the soil borings, a summary of the soils encountered by the borings, results of laboratory tests, and recommendations for structure and pavement subgrade preparation and the design of foundations, floor slabs, exterior slabs, and utilities. We are currently completing a Phase 1 ESA (Environmental Site Assessment) for this site. The Phase I ESA report was sent under separate cover. Our current scope of services did not include any other environmental services. Rachel Development, Inc. Project B2405314 February 17, 2025 Page 5 B. Results B.1. Geologic Overview We reviewed the map “Surficial Geology of the Twin Cities Metropolitan Area, Minnesota,” dated 2007. Based upon the map, the site is underlain by glacial till deposits associated with the New Ulm Formation. Glacial till associated with the Des Moines lobe typically consists of clayey soils with small but variable amounts of gravel, and lesser amounts of cobbles. The depth of soil to the bedrock surface is generally greater than 250 feet beyond the current ground surface. We based the geologic origins used in this report on the soil types, in-situ and laboratory testing, and available common knowledge of the geological history of the site. Because of the complex depositional history, geologic origins can be difficult to ascertain. B.2. Boring Results Table 1 provides a summary of the soil boring results in the general order we encountered the strata. Please refer to the Log of Boring sheets in the Appendix for additional details. The Descriptive Terminology sheet in the Appendix includes definitions of abbreviations used in Table 1. Table 1. Subsurface Profile Summary* Strata Soil Type - ASTM Classification Range of Penetration Resistances Commentary and Details Topsoil, Topsoil fill CL, SC, SM NA ▪ Encountered by all the borings and test pits. Consisted of lean clay, clayey sand, and silty sand. ▪ Thickness ranged from about 1/2 to 4 feet. ▪ Dark brown in color. ▪ Moisture condition generally moist or frozen. Swamp deposits OL, OH 3 to 5 Blows per Foot (BPF) ▪ Only encountered by Borings ST-3 and ST-4 and Test Pit TP-2 to depths of about 4 and 6 feet. ▪ Consisted of organic clay or organic silt with fibers. ▪ Black in color. ▪ Moisture condition generally moist. Alluvial deposits CL, SC 0 to 5 BPF ▪ Encountered by Borings ST-1, ST-3, and ST-4 and Test Pits TP-2. ▪ Consisted of clayey sand and lean clay. ▪ Extended to depths of about 4 to 13 feet. ▪ Color mostly brown, brownish gray and gray. ▪ Moisture condition generally moist to wet. Rachel Development, Inc. Project B2405314 February 17, 2025 Page 6 Strata Soil Type - ASTM Classification Range of Penetration Resistances Commentary and Details Glacial deposits SC, CL 4 to 28 BPF ▪ Encountered by all the borings and test pits. ▪ Consisted of clayey sand and sandy lean clay. ▪ Color mostly brown and grayish brown, transitioning to gray at depth. ▪ Moisture condition generally moist to wet. *Abbreviations defined in the attached Descriptive Terminology sheet. B.3. Groundwater While completing the soil borings, water was only observed in Boring ST-5 at a depth of about 10 1/2 feet, or an elevation of about 999 MSL. Based on the results of the soil borings, it is our opinion that the water observed in Boring ST-5 is perched within more granular soil underlain by more impervious soil. It is likely that there is a local water level near the existing pond in the northwest part of the site. Seasonal and annual fluctuations of groundwater should be anticipated. B.4. Laboratory Test Results The boring logs show the results of the laboratory testing we performed on the soil borings, next to the tested sample depth. The laboratory tests were all completed in general conformance with the applicable American Society for Testing and Materials (ASTM) standards. The Log of Boring sheets are in the Appendix of this report. The moisture content tests (ASTM D 2216) performed on selected clayey soil samples showed moisture contents ranging from about 17 to 27 percent. Most of the clayey soils tested appeared to be near or slightly above the soils’ estimated optimum moisture content, although some of the alluvial clay soils were much above their optimum moisture contents. C. Recommendations C.1. Design and Construction Discussion C.1.a. Building Subgrade Preparation Based on the results of our subsurface exploration and evaluation, spread footing foundations bearing on engineered fill and/or native soils can support the proposed houses after performing typical subgrade Rachel Development, Inc. Project B2405314 February 17, 2025 Page 7 preparation. Typical subgrade preparation includes removing existing vegetation, topsoil, or organic soils, fill, and areas of soft clay. Any existing structures, including slabs and foundations, as well as pavements and septic systems will also need to be removed. Any wells on the property will need to be properly sealed. We estimate that cuts and fills could range from about 5 to 10 feet below, or above, existing grades. Any soil correction work to further remove unsuitably soft soils could add or subtract to the assumed cut and fill depths. Based on the soil borings, soil correction work could range from around 1 to 11 feet. C.1.b. Reuse of On-Site Soils Most of the on-site soils, free of organic materials appear suitable for reuse as engineered fill. Some of the lean clay, sandy lean clay, and clayey sand will likely require some moisture conditioning to allow the recommended soil compaction levels to be achieved. This includes both drying and wetting the soils. If fill soil is mined from beneath wooded areas, the clayey soils could be dry of optimum and will need to be properly wetted if these soils are used as structural fill. The higher moisture content lean clay should not be used as structural fill below the proposed houses or streets, unless they can be properly moisture conditioned. C.1.c. Disturbance of On-Site Soils We caution that the clayey nature of some of the site soils makes them very susceptible to disturbance from construction. Care should be taken not to disturb these soils during construction, as once stable subgrades are destabilized, they will require additional moisture conditioning and compacting. C.1.d. Effects of Groundwater Groundwater is anticipated to be below typical excavation depths at this site, although perched water could be present at higher elevations within layers of granular soils overlying lower permeability soils. The contractor should immediately remove any collected water within the excavations to facilitate construction and proper backfilling. C.2. Site Grading and Subgrade Preparation C.2.a. Building Subgrade Excavations We recommend removing unsuitable materials from beneath house pads and oversize areas. We define unsuitable materials as vegetation, topsoil, organic soils, fill, existing structures, existing utilities, and soft/loose soil. Rachel Development, Inc. Project B2405314 February 17, 2025 Page 8 Table 2 shows the anticipated excavation depths and bottom of soil correction excavation elevations at each of the current soil boring and test pit locations, assuming that structures, utilities, or roads will be built at each location. Excavation depths could be reduced in areas that will not support future structures, utilities, or roads. Table 2. Recommended Excavation Depths for Building Pads and Streets Location Measured Surface Elevation (feet) Anticipated Excavation Depth (feet) Anticipated Bottom Elevation (feet) ST-1 1008.3 4 1004 ST-2 1005.8 1 1004 1/2 ST-3 995.4 Pond area --- ST-4 996.2 Pond area --- ST-5 1009.4 7 1002 1/2 ST-6 1021.2 1/2 1020 1/2 ST-7 1025.6 1 1024 1/2 ST-8 1023.3 1 1/2 1022 TP-1 1003.1 Pond area --- TP-2 996.1 Pond area --- TP-3 1005.5 Pond area --- TP-4 1018.4 1 1/2 1017 TP-5 1001.1 2 999 TP-6 1009.9 3 1007 TP-7 1019.4 4 1015 1/2 TP-8 1040.6 1/2 1040 Excavation depths will vary between the borings and test pits. Portions of the excavations may also extend deeper than indicated by the borings and test pits. A geotechnical representative should observe the excavations to make the necessary field judgments regarding the suitability of the exposed soils. Any disturbed areas should be moisture conditioned, if necessary, and re-compacted. The contractor should use equipment and techniques to reduce soil disturbance. If soils become disturbed or are wet, we recommend excavation and replacement of the disturbed or unstable soils. Provided the existing soils do not become disturbed, surface compaction will not be necessary prior to construction of footings. Rachel Development, Inc. Project B2405314 February 17, 2025 Page 9 C.2.b. Excavation Oversizing When removing unsuitable materials below structures or pavements, we recommend the excavation extend outward and downward at a slope of 1H:1V (horizontal:vertical) or flatter. See Figure 3 for an illustration of excavation oversizing. Figure 3. Generalized Illustration of Oversizing C.2.c. Excavated Slopes Based on the borings, we anticipate the near surface on-site soils in excavations will consist of mostly clayey soils. The clayey soils are typically considered Type B Soil under OSHA (Occupational Safety and Health Administration) guidelines. OSHA guidelines indicate unsupported excavations in Type B soils should have a gradient no steeper than 1:H:1V. Slopes constructed in this manner may still exhibit surface sloughing. OSHA requires an engineer to evaluate slopes or excavations over 20 feet in depth. An OSHA-approved qualified person should review the soil classification in the field. Excavations must comply with the requirements of OSHA 29 CFR, Part 1926, Subpart P, “Excavations and Trenches.” This 1. Engineered fill as defined in C.2.i 2. Excavation oversizing minimum of 1 to 1 (horizontal to vertical) slope or flatter 3. Engineered fill as required to meet pavement support or landscaping requirements as defined in C.2.i 4. Excavation back-slope to OSHA requirements Rachel Development, Inc. Project B2405314 February 17, 2025 Page 10 document states excavation safety is the responsibility of the contractor. The project specifications should reference these OSHA requirements. C.2.d. Filling on Slopes Where existing or excavated grades are steeper than 4H:1V, we recommend placing fill from low to high elevations on horizontal benches cut into the native soils so that successive lifts are spread and compacted on level surfaces, and a potential failure surface is not created along the fill’s lower boundary. Depending on fill requirements, the contractor can construct benches by cutting into existing grades while placing fill (the composition of the exposed soils thus being in compliance with fill specifications), or by cutting the benches in advance of filling (to prevent mixing with soils not in compliance with fill specifications). The height of a given bench may vary but the width should consistently be great enough to accommodate large, self-propelled compaction equipment. C.2.e. Excavation Dewatering Although likely perched water was observed in Boring ST-5, perched water could also be encountered in other parts of the site. We recommend removing any water from the excavations. Project planning should include temporary sumps and pumps for excavations in low-permeability soils, such as clays and silts. C.2.f. Selecting Excavation Backfill and Additional Required Fill On-site soils free of organic soil and debris can be considered for reuse as backfill and fill. However, the topsoil and the organic soils should not be re-used as engineered fill under the building pads or below streets. In addition, any higher moisture content lean clay soils should also not be used as engineered fill below building pads and streets unless they can be properly moisture conditioned. Some of the clayey soils on this site are both wet and dry of optimum. Therefore, drying of these soils, or wetting, will be critical to the success of the site. The wet soils should be continuously disced to lower the moisture content to near optimum. For dry clayey soils, water should be added to the soils and then thoroughly mixed with the soil to obtain a uniform moisture content in these soils. The moisture condition (drying or wetting) of the soils would be best done in the warmer less rainy months of July and August, where the soils can be properly dried, if needed. The drier months will also allow the contractor to better control the moisture content of the soil, should water need to be added to them. C.2.g. Pavement and Exterior Slab Subgrade Preparation We recommend the following steps for pavement and exterior slab subgrade preparation. Note that project planning may need to require additional subcuts to limit frost heave. Rachel Development, Inc. Project B2405314 February 17, 2025 Page 11 1. Strip unsuitable soils consisting of topsoil, organic soils, vegetation, and soft clay or existing structures and pavements from the area, down to suitable native soils below the proposed pavement surface. 2. Have a geotechnical representative observe the excavated subgrade to evaluate if additional subgrade improvements are necessary. 3. Slope subgrade soils to areas of sand or drain tile to allow the removal of accumulating water. 4. Scarify, moisture condition and surface compact the subgrade with at least 3 passes by a large roller with a minimum drum diameter of 3 1/2 feet. 5. Place pavement subgrade fill to grade and compact in accordance with Section C.2.i to bottom of pavement and exterior slab section. 6. Proofroll the pavement or exterior slab subgrade as described in Section C.2.h. C.2.h. Pavement Subgrade Proofroll After preparing the subgrade as described above and prior to the placement of the aggregate base, we recommend proofrolling the subgrade soils with a fully loaded tandem-axle truck. We also recommend having a geotechnical representative observe the proofroll. Areas that fail the proofroll likely indicate soft or weak areas that will require additional soil correction work to support pavements or slabs. The contractor should correct areas that display excessive yielding or rutting during the proofroll, as determined by the geotechnical representative. Possible options for subgrade correction include moisture conditioning and re-compaction, subcutting and replacement with soil or crushed aggregate, chemical stabilization and/or geotextiles. We recommend performing a second proofroll after the aggregate base material is in place, and prior to placing bituminous or concrete pavement/slabs. C.2.i. Engineered Fill Materials and Compaction Requirements Table 3 below contains our recommendations for engineered fill materials. Table 3. Engineered Fill Materials Locations To Be Used Engineered Fill Classification Possible Soil Type Descriptions Gradation Additional Requirements ▪ Below foundations ▪ Below interior slabs Structural fill* CL, SC 100% passing 2-inch sieve < 2% Organic Content (OC) Plasticity Index (PI) < 20% Rachel Development, Inc. Project B2405314 February 17, 2025 Page 12 Locations To Be Used Engineered Fill Classification Possible Soil Type Descriptions Gradation Additional Requirements ▪ Drainage layer ▪ Non-frost- susceptible ▪ Free-draining ▪ Non-frost- susceptible fill GP, GW, SP, SW 100% passing 1-inch sieve < 50% passing #40 sieve < 5% passing #200 sieve < 2% OC Behind below-grade walls, beyond drainage layer Retained fill SP, SP-SM, SM, SC, CL 100% passing 3-inch sieve < 20% passing #200 sieve < 2% OC PI < 4% Pavements Pavement fill CL, SC 100% passing 3-inch sieve < 2% OC PI < 20% Below landscaped surfaces, where subsidence is not a concern Non-structural fill All soil types 100% passing 6-inch sieve < 10% OC *More select soils comprised of coarse sands with < 5% passing #200 sieve may be needed to accommodate work occurring in periods of wet or freezing weather. If there are building pads that will require more than 10 feet of compacted fill under the lowest floor slabs, a construction delay may be needed if only clay fill is used to fill these building pads. The construction delay could range from 3 to 12 months, depending on the final depths of clay fill used. As an alternative, on lots where deep fills are needed, clean sand fill (less than 12 percent passing the #200 sieve) could be used to initially fill the excavations below these house pads. The clean sand fill should be placed in thin compacted lifts, up to an elevation of 10 feet or less from finished basement floor grades. (Based on the borings, this sand would need to be imported to the site.) On-site clay can then be used to complete construction of the building pads. If the alternative method of filling the house pads is used, a construction delay would not be needed. For large self-propelled vibratory compactors, we recommend spreading engineered fill in loose lifts of no more than 12 inches thick. For walk-behind compactors, we recommend spreading engineered fill in loose lifts of no more than 6 inches thick. We recommend compacting fill in accordance with the criteria presented below in Table 4. The project documents should specify relative compaction of fill, based on the structure located above the fill, and vertical proximity to that structure. Rachel Development, Inc. Project B2405314 February 17, 2025 Page 13 Table 4. Compaction Recommendations Summary Reference Relative Compaction, percent (ASTM D698 – Standard Proctor) Moisture Content Variance from Optimum, percentage points < 12% Passing #200 Sieve (SP, SP-SM) > 12% Passing #200 Sieve (CL, SC, SM) Below building pads and oversizing zones, less than 10 feet of fill. 95 *--- -1 to +3 Below building pads and oversizing zones, more than 10 feet of fill. 98 *--- -1 to +3 Within 3 feet of pavement subgrade 100 *--- -2 to +1 More than 3 feet below pavement subgrade 95 *--- -1 to +3 Below landscaped surfaces 90 *--- -1 to +5 Adjacent to below-grade wall (exterior wall backfill) 95** *--- -1 to +3 *The minimum moisture content should be no less than 5 percent and no more than 3 percentage points over optimum. **Increase compaction requirement to meet compaction required for structure supported by this engineered fill. The project documents should not allow the contractor to use frozen material as fill or to place fill on frozen material. Frost should not penetrate under foundations during construction. We recommend performing density tests in fill to evaluate if the contractors are effectively compacting the soil and meeting project requirements. Refer to Section C.3.d below for additional remarks for thicker layers of fill soils. C.3. Spread Footings C.3.a. Embedment Depth For frost protection, we recommend embedding perimeter footings of the proposed houses, including attached garages, a minimum of 42 inches below the lowest exterior grade. Interior footings may be placed directly below floor slabs unless they will be subjected to freezing. We recommend embedding building footings not heated during winter construction, and other unheated footings associated with decks, porches, or stoops, 60 inches below the lowest exterior grade. C.3.b. Subgrade Improvement If a small amount of groundwater is present within the footing excavation, or if the footing subgrade soils become disturbed prior to placing forms or reinforcement, we recommend subcutting any soft or wet Rachel Development, Inc. Project B2405314 February 17, 2025 Page 14 soil and placing a 6- to 12-inch layer of clear rock. The clear rock will provide a stable working surface and will allow for the flow of water to a drain tile or sump pump. C.3.c. Net Allowable Bearing Pressure We recommend sizing spread footings to exert a net allowable bearing pressure of up to 2,000 pounds per square foot (psf). This value includes a safety factor of at least 3.0 with regard to bearing capacity failure. C.3.d. Settlement We estimate that total and differential settlements among the footings will amount to less than 1 and 1/2 inch, respectively, under the assumed loads. If there are areas where more than 10 feet of fill is required, higher settlements could occur, unless the deeper fill areas are only filled with poorly graded sand (SP) or poorly graded sand with silt (SP-SM) fill. If deep fill areas are completed using clay soil, a construction delay may also be needed to allow the fill soils to consolidate under its own weight. Construction delays could range from 3 to 12 months, depending on the type of fill used, the compaction level obtained in the fill and the thickness of the fill. The construction delays should be evaluated after grading is completed by using settlement plates to monitor the consolidation of the fill. C.4. Basement Walls The following sections address soil parameters for basement wall design. Although construction of retaining walls has not been specified for this project to date, the following recommendations can also be used for preliminary retaining wall design. Additional soil analysis, including additional soil borings, may be needed for final retaining wall design. C.4.a. Drainage Control We recommend installing drain tile to remove water behind the below-grade walls at the location shown in Figure 4. The below-grade wall drainage system should also incorporate free-draining, engineered fill or a drainage board placed against the wall and connected to the drain tile. Even with the use of free-draining, engineered fill, we recommend general waterproofing of below-grade walls that surround occupied or potentially occupied areas because of the potential cost impacts related to seepage after construction is complete. Rachel Development, Inc. Project B2405314 February 17, 2025 Page 15 Figure 4. Generalized Illustration of Wall Engineered Fill The materials listed in the sketch should meet the definitions in Section C.4.b. The low-permeability material should be capable of directing water away from the wall, like clay, topsoil, or pavement. The project documents should indicate if the contractor should brace the walls prior to filling, and the allowable unbalanced fill heights. As shown in Figure 4, we recommend Zone 2 consist of retained, engineered fill, and this material will control lateral pressures on the wall. However, we are also providing design parameters for using other engineered fill material. If final design uses non-sand material for engineered fill, project planning should account for the following items: ▪ Other engineered fill material may result in higher lateral pressure on the wall. ▪ Other engineered fill material may be more difficult to compact. 1. 2-foot wide area of Free- Draining Engineered Fill or Drainage Board 2. Retained Engineered Fill 3. 1 foot of Low-Permeability Soil or Pavement Rachel Development, Inc. Project B2405314 February 17, 2025 Page 16 ▪ Post-construction consolidation of other engineered fill material may result in settlement- related damage to the structures or slabs supported on the engineered fill. Post-construction settlement of other engineered fill material may also cause drainage towards the structure. The magnitude of consolidation could be up to about 3 percent of the wall fill thickness. C.4.b. Selection, Placement and Compaction of Backfill Unless a drainage composite is placed against the backs of the exterior perimeter basement walls, we recommend that backfill placed within 2 horizontal feet of those walls consist of sand having less than 50 percent of the particles, by weight, passing a #40 sieve and less than 5 percent of the particles, by weight, passing a #200 sieve. If clay or silt must be considered for use to make up the balance of the below-grade wall backfill (assuming a drainage composite or sand is placed against the backs of the walls), post-compaction consolidation of the clay and silt occurring under its own weight can be expected to continue beyond the end of construction. The magnitude of consolidation could amount to between 1 and 3 percent of the backfill thickness, or wall height, and if not accommodated, could cause slabs or pavements to settle unfavorably or be damaged. Should clay or silt still be considered for use as backfill, however, we further recommend that: ▪ The bottoms of the excavations required for basement wall construction are wide enough to accommodate compaction equipment. ▪ Backfill is placed at moisture contents at least equal to, but not more than, 3 percentage points above its optimum moisture content. ▪ Backfill is placed in loose lifts no thicker than 6 inches prior to compaction. ▪ The relative compaction of the backfill is measured through density testing at intervals not exceeding 1 test per 50 horizontal feet for each 2 vertical feet of backfill placed. We recommend using a walk-behind compactor to compact the backfill placed within about 5 feet of the basement walls. Further away than that, a self-propelled compactor can be used. Compaction criteria for basement walls should be determined based on the compaction recommendations provided above in Section C.2. Exterior wall backfill not capped with slabs or pavement should be capped with a low-permeability soil to limit the infiltration of surface drainage into the backfill. The finished surface should also be sloped to divert water away from the walls. Rachel Development, Inc. Project B2405314 February 17, 2025 Page 17 C.4.c. Configuring and Resisting Lateral Loads Below-grade wall design can use active earth pressure conditions if the walls can rotate slightly. If the wall design cannot tolerate rotation, then design should use at-rest earth pressure conditions. Rotation up to 0.002 times the wall height is generally required for walls supporting sand. Rotation up to 0.02 times the wall height is required when wall supports clay. Table 5 presents our recommended lateral coefficients and equivalent fluid pressures for wall design of active, at-rest and passive earth pressure conditions. The table also provides recommended wet unit weights and internal friction angles. Designs should also consider the slope of any engineered fill and dead or live loads placed behind the walls within a horizontal distance that is equal to the height of the walls. Our recommended values assume the wall design provides drainage so water cannot accumulate behind the walls. The construction documents should clearly identify what soils the contractor should use for engineered fill of walls. Table 5. Recommended Below-Grade Wall Design Parameters – Drained Conditions Retained Soil Wet Unit Weight (pcf) Friction Angle (degrees) Equivalent Active Fluid Pressure* (pcf) Equivalent At-Rest Fluid Pressure* (pcf) Equivalent Passive Fluid Pressure* (pcf) Imported Sand (SP, SP-SM) 120 33 35 55 NA Clay Soil (CL, SC) 125 26 50 70 320 *Based on Rankine model for soils in a region behind the wall extending at least 2 horizontal feet beyond the bottom outer edges of the wall footings and then rising up and away from the wall at an angle no steeper than 60 degrees from horizontal. Sliding resistance between the bottom of the footing and the soil can also resist lateral pressures. We recommend assuming a sliding coefficient equal to 0.30 between the concrete and clay soil. The values presented in this section are un-factored. C.5. Interior Slabs C.5.a. Moisture Vapor Protection Excess transmission of water vapor could cause floor dampness, certain types of floor bonding agents to separate, or mold to form under floor coverings. If project planning includes using floor coverings or coatings, we recommend placing a vapor retarder or vapor barrier immediately beneath the slab. We also recommend consulting with floor covering manufacturers regarding the appropriate type, use and installation of the vapor retarder or barrier to preserve warranty assurances. Rachel Development, Inc. Project B2405314 February 17, 2025 Page 18 C.5.b. Radon We recommend installing radon resistant construction components for the proposed building, including appropriate sub-slab material and vent piping, if required by applicable local building codes. Our radon mitigation professionals can assist with evaluation of site-specific radon resistant construction requirements and/or design of a system, at your request. C.6. Frost Protection C.6.a. General Clayey soils will likely underlie most of the exterior slabs, as well as pavements. Most of the clayey soils are moderately to highly frost susceptible. The fine-grained soils can retain moisture and heave upon freezing. In general, this characteristic is not an issue unless these soils become saturated, due to surface runoff or infiltration, or are excessively wet in situ. Once frozen, unfavorable amounts of general and isolated heaving of the soils and the surface structures supported on them could develop. This type of heaving could affect design drainage patterns and the performance of exterior slabs and pavements, as well as any isolated exterior footings and piers. Note that general runoff and infiltration from precipitation are not the only sources of water that can saturate subgrade soils and contribute to frost heave. Roof drainage and irrigation of landscaped areas, close to exterior slabs, pavements, and isolated footings and piers, contribute as well. C.6.b. Frost Heave Mitigation To address some of the heave related issues, we recommend setting general site grades and grades for exterior surface features to direct surface drainage away from buildings, across large, paved areas and away from walkways. Such grading will limit the potential for saturation of the subgrade and subsequent heaving. General grades should also have enough “slope” to tolerate potential larger areas of heave, which may not fully settle after thawing. Even small amounts of frost-related differential movement at walkway joints or cracks can create tripping hazards. Project planning can explore several subgrade-improvement options to address this condition. One of the more conservative subgrade improvement options to mitigate potential heave is removing any frost-susceptible soils present below the exterior slab areas down to a minimum depth of 4 feet below subgrade elevations. We recommend filling the resulting excavation with non-frost-susceptible fill. We also recommend sloping the bottom of the excavation toward one or more collection points to remove any water entering the engineered fill. This approach will not be effective in controlling frost heave without removing the water. Rachel Development, Inc. Project B2405314 February 17, 2025 Page 19 An important geometric aspect of the excavation and replacement approach described above is sloping the banks of the excavations to create a more gradual transition between the unexcavated soils considered frost susceptible and the engineered fill in the excavated area, which is not frost susceptible. The slope allows attenuation of differential movement that may occur along the excavation boundary. We recommend slopes that are 3H:1V, or flatter, along transitions between frost-susceptible and non- frost-susceptible soils. Figure 5 that follows shows an illustration summarizing some of the recommendations. Figure 5. Frost Protection Geometry Illustration Another option is to limit frost heave in critical areas, such as doorways and entrances, via frost-depth footings or localized excavations with sloped transitions between frost-susceptible and non-frost- susceptible soils, as described above. Over the life of slabs and pavements, cracks will develop, and joints will open which will expose the subgrade and allow water to enter from the surface and either saturate or perch atop the subgrade soils. This water intrusion increases the potential for frost heave or moisture-related distress near the crack or joint. Therefore, we recommend implementing a detailed maintenance program to seal and/or fill any cracks and joints. The maintenance program should give special attention to areas where dissimilar materials abut one another, where construction joints occur and where shrinkage cracks develop. Rachel Development, Inc. Project B2405314 February 17, 2025 Page 20 C.7. Pavements C.7.a. Design Sections Our scope of services for this project did not include laboratory tests on subgrade soils to determine an R-value for pavement design. Since much of the soils on this site consist of clay, we recommend that the pavements be designed for an assume R-value of 12. Note the contractor may need to perform limited removal of unsuitable or less suitable soils to achieve this value. We assumed that pavements for the residential development will be subject to a maximum of 50,000 ESALs over a 20-year design life. We assume the pavements will be designed in accordance with the City of Chanhassen standard pavement section which includes a sand subbase. C.7.b. Bituminous Pavement Materials Appropriate mix designs are critical to the performance of flexible pavements. We can provide recommendations for pavement material selection during final pavement design. C.7.c. Subgrade Drainage We recommend installing perforated drainpipes throughout pavement areas at low points, around catch basins, and behind curb in landscaped areas. We also recommend installing drainpipes along pavement and exterior slab edges where exterior grades promote drainage toward those edge areas. The contractor should place drainpipes at the base of the granular subbase layer, or in shallow trenches, extending just below the aggregate base material where no subbase is present. C.7.d. Performance and Maintenance We based the above pavement designs on a 20-year performance life for bituminous. This is the amount of time before we anticipate the pavement will require reconstruction. This performance life assumes routine maintenance, such as seal coating and crack sealing. The actual pavement life will vary depending on variations in weather, traffic conditions and maintenance. It is common to place the non-wear course of bituminous and then delay placement of the wear course. For this situation, we recommend evaluating if the reduced pavement section will have sufficient structure to support construction traffic. Many conditions affect the overall performance of the exterior slabs and pavements. Some of these conditions include the environment, loading conditions and the level of ongoing maintenance. With bituminous pavements, it is common to have thermal cracking develop within the first few years of placement and continue throughout the life of the pavement. We recommend developing a regular Rachel Development, Inc. Project B2405314 February 17, 2025 Page 21 maintenance plan for filling cracks in exterior slabs and pavements to lessen the potential impacts for cold weather distress due to frost heave or warm weather distress due to wetting and softening of the subgrade. C.8. Utilities C.8.a. Subgrade Stabilization Earthwork activities associated with utility installations located inside building pad areas should adhere to the recommendations in Section C.2. For exterior utilities, we anticipate the soils at typical invert elevations will be suitable for utility support. However, if construction encounters unfavorable conditions such as soft clay, very loose silt, organic soils or perched water at invert grades, the unsuitable soils may require some additional subcutting and replacement with sand or crushed rock to prepare a proper subgrade for pipe support. Project design and construction should not place utilities within the 1H:1V oversizing of foundations. C.8.b. Selection, Placement, and Compaction of Backfill We recommend selecting, placing, and compacting utility backfill in accordance with the recommendations provided above in Section C.2.i. C.8.c. Corrosion Potential Based on our experience, some of the clayey soils encountered by the borings are moderately corrosive to metallic conduits. We recommend specifying non-corrosive materials or providing corrosion protection, unless project planning chooses to perform additional tests to demonstrate the soils are not corrosive. C.9. Stormwater Based on borings performed, the majority of onsite soils consist of clayey soils. These soils are consistent with Hydrologic Soil Group D of the Minnesota Stormwater Manual and not conducive to soil infiltration. While limited amounts of sand soils were encountered, we do not anticipate that significant quantities of these can be located for stormwater infiltration. For stormwater design, we recommend consulting the Minnesota Stormwater Manual. This Geotechnical Evaluation does not constitute a review of site suitability for stormwater infiltration or evaluate the potential impacts, if any, from infiltration of large amounts of stormwater. Rachel Development, Inc. Project B2405314 February 17, 2025 Page 22 D. Procedures D.1. Penetration Test Borings We drilled the penetration test borings on June 20, 2024, with an off-road-mounted core and auger drill equipped with hollow-stem auger. We performed the borings in general accordance with ASTM D6151 taking penetration test samples at 2 1/2- or 5-foot intervals in general accordance with ASTM D1586. The boring logs show the actual sample intervals and corresponding depths. We sealed penetration test boreholes meeting the Minnesota Department of Health (MDH) Environmental Borehole criteria with an MDH-approved grout, with sealing record submitted, as required. D.2. Exploration Logs D.2.a. Log of Boring Sheets The Appendix includes Log of Boring sheets for our penetration test borings. The logs identify and describe the penetrated geologic materials and present the results of penetration resistance and other in-situ tests performed. The logs also present the results of laboratory tests performed on penetration test samples, and groundwater measurements. We inferred strata boundaries from changes in the penetration test samples and the auger cuttings. Because we did not perform continuous sampling, the strata boundary depths are only approximate. The boundary depths likely vary away from the boring locations, and the boundaries themselves may occur as gradual rather than abrupt transitions. D.2.b. Log of Test Pit Sheets The Appendix also includes Log of Test Pit sheets. The logs classify and describe the geologic materials exposed in the sidewalls and bottoms of the pits, present the results of laboratory tests performed on bulk samples obtained from them, and depict groundwater measurements. D.2.c. Geologic Origins We assigned geologic origins to the materials shown on the logs and referenced within this report, based on: (1) a review of the background information and reference documents cited above, (2) visual classification of the various geologic material samples retrieved during the course of our subsurface exploration, (3) penetration resistance and other in-situ testing performed for the project, (4) laboratory test results, and (5) available common knowledge of the geologic processes and environments that have impacted the site and surrounding area in the past. Rachel Development, Inc. Project B2405314 February 17, 2025 Page 23 D.3. Material Classification and Testing D.3.a. Visual and Manual Classification We visually and manually classified the geologic materials encountered based on ASTM D2488. When we performed laboratory classification tests, we used the results to classify the geologic materials in accordance with ASTM D2487. The Appendix includes a chart explaining the classification system we used. D.3.b. Laboratory Testing The exploration logs in the Appendix note the results of the laboratory tests performed on geologic material samples. We performed the tests in general accordance with ASTM procedures. D.4. Groundwater Measurements The drillers checked for groundwater while advancing the penetration test borings, and again after auger withdrawal. We then immediately filled the boreholes, as described in our scope in our authorized scope of work and as noted on the boring log. E. Qualifications E.1. Variations in Subsurface Conditions E.1.a. Material Strata We developed our evaluation, analyses, and recommendations from a limited amount of site and subsurface information. It is not standard engineering practice to retrieve material samples from exploration locations continuously with depth. Therefore, we must infer strata boundaries and thicknesses to some extent. Strata boundaries may also be gradual transitions, and project planning should expect the strata to vary in depth, elevation, and thickness, away from the exploration locations. Variations in subsurface conditions present between exploration locations may not be revealed until performing additional exploration work or starting construction. If future activity for this project reveals any such variations, you should notify us so that we may reevaluate our recommendations. Such variations could increase construction costs, and we recommend including a contingency to accommodate them. Rachel Development, Inc. Project B2405314 February 17, 2025 Page 24 E.1.b. Groundwater Levels We made groundwater measurements under the conditions reported herein and shown on the exploration logs and interpreted in the text of this report. Note that the observation periods were relatively short, and project planning can expect groundwater levels to fluctuate in response to rainfall, flooding, irrigation, seasonal freezing and thawing, surface drainage modifications and other seasonal and annual factors. E.2. Continuity of Professional Responsibility E.2.a. Plan Review We based this report on a limited amount of information, and we made several assumptions to help us develop our recommendations. Braun Intertec should be retained to review the geotechnical aspects of the designs and specifications. This review will allow us to evaluate whether we anticipated the design correctly, if any design changes affect the validity of our recommendations, and if the design and specifications correctly interpret and implement our recommendations. Braun Intertec should also be retained to complete the soil observations and testing as the site is being graded. E.2.b. Construction Observations and Testing We recommend retaining Braun Intertec to perform the required observations and testing during construction as part of the ongoing geotechnical evaluation. This will allow us to correlate the subsurface conditions exposed during construction with those encountered by the borings and provide professional continuity from the design phase to the construction phase. If we do not perform observations and testing during construction, it becomes the responsibility of others to validate the assumption made during the preparation of this report and to accept the construction-related geotechnical engineer-of- record responsibilities. E.3. Use of Report This report is for the exclusive use of the addressed parties. Without written approval, we assume no responsibility to other parties regarding this report. Our evaluation, analyses and recommendations may not be appropriate for other parties or projects. E.4. Standard of Care In performing its services, Braun Intertec used that degree of care and skill ordinarily exercised under similar circumstances by reputable members of its profession currently practicing in the same locality. No warranty, express or implied, is made. Appendix EXPAND AND RESHAPE EXISTING POND 1 23 4 6 7 8 9 10 11 1213 14 15 16 17 18 19 5 1000' Shoreland Bndy 20078 sf 19452 sf 19130 sf 19462 sf ST-1ST-2 ST-5 ST-4 ST-3 ST-6 ST-7 ST-8POWERS BOULEVARDPLEASANTVI E W R O A D LAKE LUCY ROAD TROENDLE CIRCLENEZ PERCE DRIVEVINELAND COURT TP-8 TP-7 TP-6 TP-5 TP-4 TP-1 TP-3 TP-2 F:\2024\B2405314\CAD\B2405314.dwg,Geotech,1/27/2025 10:53:29 AMbraunintertec.com 952.995.2000 Minneapolis, MN 55438 11001 Hampshire Avenue S Project No: B2405314 Drawn By: Date Drawn: Checked By: Last Modified:1/27/25 Drawing No: Project Information Drawing Information B2405314 JAG 6/12/24 JLW Pleasant View Pointe Development 6535 Peaceful Lane Chanhassen, Minnesota Soil Boring Location SketchN DENOTES APPROXIMATE LOCATION OF TEST PIT 0 SCALE:1"= 150' 150'75' DENOTES APPROXIMATE LOCATION OF STANDARD PENETRATION TEST BORING Elev./ Depth ft 1007.3 1.0 1004.3 4.0 993.8 14.5 WaterLevelDescription of Materials (Soil-ASTM D2488 or 2487; Rock-USACE EM 1110-1-2908) CLAYEY SAND (SC), trace roots, dark brown, moist (TOPSOIL) LEAN CLAY (CL), brownish gray, moist, soft, rust staining (ALLUVIUM) CLAYEY SAND (SC), contains lenses of Poorly Graded Sand with Silt, trace Gravel, brown, moist, stiff to very stiff (GLACIAL TILL) END OF BORING Boring then backfilled with bentonite chips 5 10 15 20 25 30 SampleBlows (N-Value) Recovery 3-1-3 (4) 18" 3-8-5 (13) 18" 3-5-6 (11) 18" 3-4-8 (12) 18" 5-8-12-14 (20) 16" qₚ tsf MC % 25 Tests or Remarks Water not observed while drilling. LOG OF BORING See Descriptive Terminology sheet for explanation of abbreviations Project Number B2405314 Geotechnical Evaluation Pleasant View Pointe Development 6535 Peaceful Lane Chanhassen, Minnesota BORING:ST-1 LOCATION: Captured with RTK GPS. DATUM:NAD 1983 HARN Adj MN Carver (US Feet) NORTHING:190270.2 EASTING:557415.4 DRILLER:M Barber/C McClain LOGGED BY:J Carlson START DATE:06/20/24 END DATE:06/20/24 SURFACE ELEVATION:1008.3 ft RIG:GP-1 METHOD:3 1/4" HSA SURFACING:Grass WEATHER:Cloudy, 60°F B2405314 Braun Intertec Corporation Print Date:02/17/2025 ST-1 page 1 of 1DRAFT Elev./ Depth ft 1005.1 0.7 991.3 14.5 WaterLevelDescription of Materials (Soil-ASTM D2488 or 2487; Rock-USACE EM 1110-1-2908) SANDY LEAN CLAY (CL), trace roots, dark brown, moist (TOPSOIL) CLAYEY SAND (SC), trace Gravel, brown to grayish brown, moist, stiff, rust staining (GLACIAL TILL) END OF BORING Boring then backfilled with bentonite chips 5 10 15 20 25 30 SampleBlows (N-Value) Recovery 2-6-6 (12) 16" 4-7-7 (14) 16" 3-5-5 (10) 18" 3-5-8 (13) 15" 4-6-8-8 (14) 14" qₚ tsf MC % 18 Tests or Remarks Water not observed while drilling. LOG OF BORING See Descriptive Terminology sheet for explanation of abbreviations Project Number B2405314 Geotechnical Evaluation Pleasant View Pointe Development 6535 Peaceful Lane Chanhassen, Minnesota BORING:ST-2 LOCATION: Captured with RTK GPS. DATUM:NAD 1983 HARN Adj MN Carver (US Feet) NORTHING:190272.8 EASTING:557267.9 DRILLER:M Barber/C McClain LOGGED BY:J Carlson START DATE:06/20/24 END DATE:06/20/24 SURFACE ELEVATION:1005.8 ft RIG:GP-1 METHOD:3 1/4" HSA SURFACING:Grass WEATHER:Cloudy, 60°F B2405314 Braun Intertec Corporation Print Date:02/17/2025 ST-2 page 1 of 1DRAFT Elev./ Depth ft 995.0 0.4 993.4 2.0 991.4 4.0 986.4 9.0 975.4 20.0 WaterLevelDescription of Materials (Soil-ASTM D2488 or 2487; Rock-USACE EM 1110-1-2908) SANDY LEAN CLAY (CL), trace roots, dark brown, moist (TOPSOIL FILL) FILL: CLAYEY SAND (SC), brown, moist ORGANIC SILT (OH), trace fibers, black, moist (SWAMP DEPOSIT) CLAYEY SAND (SC), trace Gravel, trace fibers, gray and brown, moist, very soft to soft (ALLUVIUM) CLAYEY SAND (SC), trace Gravel, gray and brown to gray, moist, medium to stiff (GLACIAL TILL) END OF BORING Boring then backfilled with bentonite chips 5 10 15 20 25 30 SampleBlows (N-Value) Recovery 0-2-3 (5) 18" 0-0-0 WOH/18" 18" 0-1-2 (3) 18" 1-3-3 (6) 18" 1-3-4 (7) 18" 3-5-7 (12) 18" 3-5-7 (12) 18" qₚ tsf MC % 20 Tests or Remarks Water not observed while drilling. LOG OF BORING See Descriptive Terminology sheet for explanation of abbreviations Project Number B2405314 Geotechnical Evaluation Pleasant View Pointe Development 6535 Peaceful Lane Chanhassen, Minnesota BORING:ST-3 LOCATION: Captured with RTK GPS. DATUM:NAD 1983 HARN Adj MN Carver (US Feet) NORTHING:190105.1 EASTING:557074.6 DRILLER:M Barber/C McClain LOGGED BY:J Carlson START DATE:06/20/24 END DATE:06/20/24 SURFACE ELEVATION:995.4 ft RIG:GP-1 METHOD:3 1/4" HSA SURFACING:Grass WEATHER:Cloudy, 60°F B2405314 Braun Intertec Corporation Print Date:02/17/2025 ST-3 page 1 of 1DRAFT Elev./ Depth ft 994.9 1.3 990.2 6.0 982.2 14.0 976.2 20.0 WaterLevelDescription of Materials (Soil-ASTM D2488 or 2487; Rock-USACE EM 1110-1-2908) CLAYEY SAND (SC), trace roots, dark brown, moist (TOPSOIL) ORGANIC SILT (OH), trace fibers, black, moist (SWAMP DEPOSIT) CLAYEY SAND (SC), trace Gravel, brownish gray, moist, very soft to medium (ALLUVIUM) CLAYEY SAND (SC), contains lenses of Poorly Graded Sand, trace Gravel, gray, moist, soft to stiff (GLACIAL TILL) END OF BORING Boring then backfilled with bentonite chips 5 10 15 20 25 30 SampleBlows (N-Value) Recovery 0-1-2 (3) 18" 0-3-2 (5) 18" 0-0-0 WOH/18" 16" 0-0-0 WOH/18" 18" 0-2-3 (5) 18" 0-1-3 (4) 18" 1-4-6 (10) 18" qₚ tsf MC % 23 Tests or Remarks Water not observed while drilling. LOG OF BORING See Descriptive Terminology sheet for explanation of abbreviations Project Number B2405314 Geotechnical Evaluation Pleasant View Pointe Development 6535 Peaceful Lane Chanhassen, Minnesota BORING:ST-4 LOCATION: Captured with RTK GPS. DATUM:NAD 1983 HARN Adj MN Carver (US Feet) NORTHING:190107.0 EASTING:556957.4 DRILLER:M Barber/C McClain LOGGED BY:J Carlson START DATE:06/20/24 END DATE:06/20/24 SURFACE ELEVATION:996.2 ft RIG:GP-1 METHOD:3 1/4" HSA SURFACING:Grass WEATHER:Cloudy, 60°F B2405314 Braun Intertec Corporation Print Date:02/17/2025 ST-4 page 1 of 1DRAFT Elev./ Depth ft 1008.9 0.5 1002.4 7.0 989.4 20.0 WaterLevelDescription of Materials (Soil-ASTM D2488 or 2487; Rock-USACE EM 1110-1-2908) SILTY SAND (SM), fine-grained, trace roots, dark brown, moist (TOPSOIL) CLAYEY SAND (SC), contains lenses and seams of Poorly Graded Sand, trace Gravel, brown, moist, very soft to soft (ALLUVIUM) CLAYEY SAND (SC), trace Gravel, brown to grayish brown, moist to wet, medium to stiff (GLACIAL TILL) END OF BORING Boring then backfilled with bentonite chips 5 10 15 20 25 30 SampleBlows (N-Value) Recovery 0-2-2 (4) 18" 0-0-0 WOH/18" 18" 3-4-5 (9) 18" 3-3-4 (7) 18" 3-4-6 (10) 18" 3-5-6 (11) 18" 4-5-6 (11) 18" qₚ tsf MC % 27 20 Tests or Remarks Water observed at 10.5 feet while drilling. Water observed at 17.5 feet at end of drilling. LOG OF BORING See Descriptive Terminology sheet for explanation of abbreviations Project Number B2405314 Geotechnical Evaluation Pleasant View Pointe Development 6535 Peaceful Lane Chanhassen, Minnesota BORING:ST-5 LOCATION: Captured with RTK GPS. DATUM:NAD 1983 HARN Adj MN Carver (US Feet) NORTHING:189997.3 EASTING:556926.7 DRILLER:M Barber/C McClain LOGGED BY:J Carlson START DATE:06/20/24 END DATE:06/20/24 SURFACE ELEVATION:1009.4 ft RIG:GP-1 METHOD:3 1/4" HSA SURFACING:Weed WEATHER:Cloudy, 60°F B2405314 Braun Intertec Corporation Print Date:02/17/2025 ST-5 page 1 of 1DRAFT Elev./ Depth ft 1020.8 0.4 1006.7 14.5 WaterLevelDescription of Materials (Soil-ASTM D2488 or 2487; Rock-USACE EM 1110-1-2908) CLAYEY SAND (SC), trace roots, dark brown, moist (TOPSOIL) CLAYEY SAND (SC), contains lenses of Poorly Graded Sand, trace Gravel, brown and gray, moist, medium to stiff (GLACIAL TILL) END OF BORING Boring then backfilled with bentonite chips 5 10 15 20 25 30 SampleBlows (N-Value) Recovery 0-2-3 (5) 18" 2-4-6 (10) 18" 3-4-6 (10) 18" 4-6-10 (16) 18" 6-14-14 (28) 18" qₚ tsf MC % 17 Tests or Remarks Water not observed while drilling. LOG OF BORING See Descriptive Terminology sheet for explanation of abbreviations Project Number B2405314 Geotechnical Evaluation Pleasant View Pointe Development 6535 Peaceful Lane Chanhassen, Minnesota BORING:ST-6 LOCATION: Captured with RTK GPS. DATUM:NAD 1983 HARN Adj MN Carver (US Feet) NORTHING:189725.8 EASTING:557003.4 DRILLER:M Barber/C McClain LOGGED BY:J Carlson START DATE:06/20/24 END DATE:06/20/24 SURFACE ELEVATION:1021.2 ft RIG:GP-1 METHOD:3 1/4" HSA SURFACING:Grass WEATHER:Cloudy, 60°F B2405314 Braun Intertec Corporation Print Date:02/17/2025 ST-6 page 1 of 1DRAFT Elev./ Depth ft 1024.7 0.8 1011.1 14.5 WaterLevelDescription of Materials (Soil-ASTM D2488 or 2487; Rock-USACE EM 1110-1-2908) CLAYEY SAND (SC), trace roots, dark brown, moist (TOPSOIL) CLAYEY SAND (SC), contains lenses of Poorly Graded Sand, trace Gravel, brown and gray to brown, moist, medium to very stiff (GLACIAL TILL) END OF BORING Boring then backfilled with bentonite chips 5 10 15 20 25 30 SampleBlows (N-Value) Recovery 1-2-3 (5) 7" 0-3-4 (7) 18" 2-4-5 (9) 18" 1-4-5 (9) 18" 8-9-11-11 (20) 24" qₚ tsf MC % 20 Tests or Remarks Water not observed while drilling. LOG OF BORING See Descriptive Terminology sheet for explanation of abbreviations Project Number B2405314 Geotechnical Evaluation Pleasant View Pointe Development 6535 Peaceful Lane Chanhassen, Minnesota BORING:ST-7 LOCATION: Captured with RTK GPS. DATUM:NAD 1983 HARN Adj MN Carver (US Feet) NORTHING:189625.4 EASTING:556911.9 DRILLER:M Barber/C McClain LOGGED BY:J Carlson START DATE:06/20/24 END DATE:06/20/24 SURFACE ELEVATION:1025.6 ft RIG:GP-1 METHOD:3 1/4" HSA SURFACING:Grass WEATHER:Cloudy, 60°F B2405314 Braun Intertec Corporation Print Date:02/17/2025 ST-7 page 1 of 1DRAFT Elev./ Depth ft 1022.1 1.2 1019.3 4.0 1014.3 9.0 1008.8 14.5 WaterLevelDescription of Materials (Soil-ASTM D2488 or 2487; Rock-USACE EM 1110-1-2908) CLAYEY SAND (SC), trace roots, dark brown, moist (TOPSOIL) SANDY LEAN CLAY (CL), brown, moist, medium, rust staining (ALLUVIUM) SANDY LEAN CLAY (CL), trace Gravel, brown, moist, medium to stiff (GLACIAL TILL) CLAYEY SAND (SC), trace Gravel, brown, moist, stiff to very stiff (GLACIAL TILL) END OF BORING Boring then backfilled with bentonite chips 5 10 15 20 25 30 SampleBlows (N-Value) Recovery 1-2-3 (5) 18" 2-2-4 (6) 18" 3-4-5 (9) 18" 4-5-8 (13) 18" 4-7-14 (21) 18" qₚ tsf MC % 18 Tests or Remarks Water not observed while drilling. LOG OF BORING See Descriptive Terminology sheet for explanation of abbreviations Project Number B2405314 Geotechnical Evaluation Pleasant View Pointe Development 6535 Peaceful Lane Chanhassen, Minnesota BORING:ST-8 LOCATION: Captured with RTK GPS. DATUM:NAD 1983 HARN Adj MN Carver (US Feet) NORTHING:189356.8 EASTING:556921.9 DRILLER:M Barber/C McClain LOGGED BY:J Carlson START DATE:06/20/24 END DATE:06/20/24 SURFACE ELEVATION:1023.3 ft RIG:GP-1 METHOD:3 1/4" HSA SURFACING:Grass WEATHER:Cloudy, 60°F B2405314 Braun Intertec Corporation Print Date:02/17/2025 ST-8 page 1 of 1DRAFT Elev./ Depth ft 1002.1 1.0 995.1 8.0 992.1 11.0 WaterLevelDescription of Materials (Soil-ASTM D2488 or 2487) CLAYEY SAND (SC), trace roots, dark brown, frozen (moist when thawed) (TOPSOIL FILL) FILL: CLAYEY SAND (SC), trace Gravel, brown, moist CLAYEY SAND (SC), trace Gravel, with SILTY SAND layers, mottled brown, moist (GLACIAL TILL) END OF TEST PIT Test pit then backfilled with spoils 5 10 SampleSample Blows Recovery qₚ tsf MC %Tests or Remarks Surface elevations provided by Rachel Development Water not observed while excavating. LOG OF TEST PIT See Descriptive Terminology sheet for explanation of abbreviations Project Number B2405314 Geotechnical Evaluation Pleasant View Pointe Development 6535 Peaceful Lane Chanhassen, Minnesota TEST PIT:TP-1 LOCATION: See attached sketch DATUM: NORTHING:EASTING: EXCAVATOR:Rachel Contracting LOGGED BY:J Carlson START DATE:01/08/25 END DATE:01/08/25 SURFACE ELEVATION:1003.1 ft RIG:Excavator SURFACING:Topsoil WEATHER:Sun, 10°F B2405314 Braun Intertec Corporation Print Date:02/17/2025 TP-1 page 1 of 1DRAFT Elev./ Depth ft 995.1 1.0 990.1 6.0 983.1 13.0 981.1 15.0 WaterLevelDescription of Materials (Soil-ASTM D2488 or 2487) SILTY SAND (SM), trace roots, dark brown, frozen (moist when thawed) (TOPSOIL FILL) ORGANIC CLAY (OH), black, moist (SWAMP DEPOSIT) LEAN CLAY (CL), gray, moist, soft (ALLUVIUM) SANDY LEAN CLAY (CL), trace Gravel, brown, moist (GLACIAL TILL) END OF TEST PIT Test pit then backfilled with spoils 5 10 SampleSample Blows Recovery qₚ tsf MC %Tests or Remarks Too much steam to evaluate groundwater LOG OF TEST PIT See Descriptive Terminology sheet for explanation of abbreviations Project Number B2405314 Geotechnical Evaluation Pleasant View Pointe Development 6535 Peaceful Lane Chanhassen, Minnesota TEST PIT:TP-2 LOCATION: See attached sketch DATUM: NORTHING:EASTING: EXCAVATOR:Rachel Contracting LOGGED BY:J Carlson START DATE:01/08/25 END DATE:01/08/25 SURFACE ELEVATION:996.1 ft RIG:Excavator SURFACING:Topsol WEATHER:Sun, 10°F B2405314 Braun Intertec Corporation Print Date:02/17/2025 TP-2 page 1 of 1DRAFT Elev./ Depth ft 1004.5 1.0 992.5 13.0 991.5 14.0 WaterLevelDescription of Materials (Soil-ASTM D2488 or 2487) SANDY LEAN CLAY (CL), trace roots, dark brown, frozen (moist when thawed) (TOPSOIL FILL) FILL: SANDY LEAN CLAY (CL), trace Gravel, brown and dark brown, moist SANDY LEAN CLAY (CL), trace Gravel, mottled brown, moist (GLACIAL TILL) END OF TEST PIT Test pit then backfilled with spoils 5 10 SampleSample Blows Recovery qₚ tsf MC %Tests or Remarks Water not observed while excavating. LOG OF TEST PIT See Descriptive Terminology sheet for explanation of abbreviations Project Number B2405314 Geotechnical Evaluation Pleasant View Pointe Development 6535 Peaceful Lane Chanhassen, Minnesota TEST PIT:TP-3 LOCATION: See attached sketch DATUM: NORTHING:EASTING: EXCAVATOR:Rachel Contracting LOGGED BY:J Carlson START DATE:01/08/25 END DATE:01/08/25 SURFACE ELEVATION:1005.5 ft RIG:Excavator SURFACING:Topsoil WEATHER:Sun, 10°F B2405314 Braun Intertec Corporation Print Date:02/17/2025 TP-3 page 1 of 1DRAFT Elev./ Depth ft 1016.9 1.5 1012.4 6.0 WaterLevelDescription of Materials (Soil-ASTM D2488 or 2487) SANDY LEAN CLAY (CL), trace roots, dark brown, frozen (moist when thawed) (TOPSOIL) SANDY LEAN CLAY (CL), trace Gravel, brown, moist (GLACIAL TILL) END OF TEST PIT Test pit then backfilled with spoils 5 10 SampleSample Blows Recovery qₚ tsf MC %Tests or Remarks Water not observed while excavating. LOG OF TEST PIT See Descriptive Terminology sheet for explanation of abbreviations Project Number B2405314 Geotechnical Evaluation Pleasant View Pointe Development 6535 Peaceful Lane Chanhassen, Minnesota TEST PIT:TP-4 LOCATION: See attached sketch DATUM: NORTHING:EASTING: EXCAVATOR:Rachel Contracting LOGGED BY:J Carlson START DATE:01/08/25 END DATE:01/08/25 SURFACE ELEVATION:1018.4 ft RIG:Excavator SURFACING:Topsoil WEATHER:Sun, 10°F B2405314 Braun Intertec Corporation Print Date:02/17/2025 TP-4 page 1 of 1DRAFT Elev./ Depth ft 999.1 2.0 995.1 6.0 WaterLevelDescription of Materials (Soil-ASTM D2488 or 2487) CLAYEY SAND (SC), trace roots, dark brown, frozen (moist when thawed) (TOPSOIL) CLAYEY SAND (SC), trace Gravel, brown, moist (GLACIAL TILL) END OF TEST PIT Test pit then backfilled with spoils 5 10 SampleSample Blows Recovery qₚ tsf MC %Tests or Remarks Water not observed while excavating. LOG OF TEST PIT See Descriptive Terminology sheet for explanation of abbreviations Project Number B2405314 Geotechnical Evaluation Pleasant View Pointe Development 6535 Peaceful Lane Chanhassen, Minnesota TEST PIT:TP-5 LOCATION: See attached sketch DATUM: NORTHING:EASTING: EXCAVATOR:Rachel Contracting LOGGED BY:J Carlson START DATE:01/08/25 END DATE:01/08/25 SURFACE ELEVATION:1001.1 ft RIG:Excavator SURFACING:Topsoil WEATHER:Sun, 10°F B2405314 Braun Intertec Corporation Print Date:02/17/2025 TP-5 page 1 of 1DRAFT Elev./ Depth ft 1009.4 0.5 1006.9 3.0 1001.9 8.0 WaterLevelDescription of Materials (Soil-ASTM D2488 or 2487) CLAYEY SAND (SC), trace roots, dark brown, frozen (moist when thawed) (TOPSOIL FILL) FILL: CLAYEY SAND (SC), trace Gravel, dark brown, moist CLAYEY SAND (SC), trace Gravel, brown, moist (GLACIAL TILL) END OF TEST PIT Test pit then backfilled with spoils 5 10 SampleSample Blows Recovery qₚ tsf MC %Tests or Remarks Water not observed while excavating. LOG OF TEST PIT See Descriptive Terminology sheet for explanation of abbreviations Project Number B2405314 Geotechnical Evaluation Pleasant View Pointe Development 6535 Peaceful Lane Chanhassen, Minnesota TEST PIT:TP-6 LOCATION: See attached sketch DATUM: NORTHING:EASTING: EXCAVATOR:Rachel Contracting LOGGED BY:J Carlson START DATE:01/08/25 END DATE:01/08/25 SURFACE ELEVATION:1009.9 ft RIG:Excavator SURFACING:Topsoi WEATHER:Sun, 10°F B2405314 Braun Intertec Corporation Print Date:02/17/2025 TP-6 page 1 of 1DRAFT Elev./ Depth ft 1015.4 4.0 1013.4 6.0 WaterLevelDescription of Materials (Soil-ASTM D2488 or 2487) CLAYEY SAND (SC), trace roots, dark brown, frozen (moist when thawed) (TOPSOIL FILL) CLAYEY SAND (SC), trace Gravel, brown, moist (GLACIAL TILL) END OF TEST PIT Test pit then backfilled with spoils 5 10 SampleSample Blows Recovery qₚ tsf MC %Tests or Remarks Water not observed while excavating. LOG OF TEST PIT See Descriptive Terminology sheet for explanation of abbreviations Project Number B2405314 Geotechnical Evaluation Pleasant View Pointe Development 6535 Peaceful Lane Chanhassen, Minnesota TEST PIT:TP-7 LOCATION: See attached sketch DATUM: NORTHING:EASTING: EXCAVATOR:Rachel Contracting LOGGED BY:J Carlson START DATE:01/08/25 END DATE:01/08/25 SURFACE ELEVATION:1019.4 ft RIG:Excavator SURFACING:Topsoil WEATHER:Sun, 10°F B2405314 Braun Intertec Corporation Print Date:02/17/2025 TP-7 page 1 of 1DRAFT Elev./ Depth ft 1040.1 0.5 1035.6 5.0 WaterLevelDescription of Materials (Soil-ASTM D2488 or 2487) CLAYEY SAND (SC), trace roots, dark brown, frozen (moist when thawed) (TOPSOIL) CLAYEY SAND (SC), trace Gravel, brown, moist (GLACIAL TILL) END OF TEST PIT Test pit then backfilled with spoils 5 10 SampleSample Blows Recovery qₚ tsf MC %Tests or Remarks Water not observed while excavating. LOG OF TEST PIT See Descriptive Terminology sheet for explanation of abbreviations Project Number B2405314 Geotechnical Evaluation Pleasant View Pointe Development 6535 Peaceful Lane Chanhassen, Minnesota TEST PIT:TP-8 LOCATION: See attached sketch DATUM: NORTHING:EASTING: EXCAVATOR:Rachel Contracting LOGGED BY:J Carlson START DATE:01/08/25 END DATE:01/08/25 SURFACE ELEVATION:1040.6 ft RIG:Excavator SURFACING:Topsoil WEATHER:Sun, 10°F B2405314 Braun Intertec Corporation Print Date:02/17/2025 TP-8 page 1 of 1DRAFT Descriptive Terminology of Soil Based on Standards ASTM D2487/2488 (Unified Soil Classification System) Group Symbol Group NameB Cu ≥ 4 and 1 ≤ Cc ≤ 3D GW Well‐graded gravelE Cu < 4 and/or (Cc < 1 or Cc > 3)D GP Poorly graded gravelE Fines classify as ML or MH GM Silty gravelE F G Fines Classify as CL or CH GC Clayey gravelE F G Cu ≥ 6 and 1 ≤ Cc ≤ 3D SW Well‐graded sandI Cu < 6 and/or (Cc < 1 or Cc > 3)D SP Poorly graded sandI Fines classify as ML or MH SM Silty sandF G I Fines classify as CL or CH SC Clayey sandF G I CL Lean clayK L M PI < 4 or plots below "A" lineJ ML SiltK L M Organic OL CH Fat clayK L M MH Elastic siltK L M Organic OH PT Peat Highly Organic Soils Silts and Clays (Liquid limit less than 50) Silts and Clays (Liquid limit 50 or more) Primarily organic matter, dark in color, and organic odor Inorganic Inorganic PI > 7 and plots on or above "A" lineJ PI plots on or above "A" line PI plots below "A" line Criteria for Assigning Group Symbols and Group Names Using Laboratory TestsA Soil Classification Coarse‐grained Soils (more than 50% retained on No. 200 sieve)Fine‐grained Soils (50% or more passes the No. 200 sieve) Sands (50% or more coarse fraction passes No. 4 sieve) Clean Gravels (Less than 5% finesC) Gravels with Fines (More than 12% finesC) Clean Sands (Less than 5% finesH) Sands with Fines (More than 12% finesH) Gravels (More than 50% of coarse fraction retained on No. 4 sieve) Liquid Limit − oven dried Liquid Limit − not dried <0.75 Organic clay K L M N Organic silt K L M O Liquid Limit − oven dried Liquid Limit − not dried <0.75 Organic clay K L M P Organic silt K L M Q ParticleSize Identification Boulders.............. over 12" Cobbles................ 3" to 12" Gravel Coarse............. 3/4" to 3" (19.00 mm to 75.00 mm) Fine................. No. 4 to 3/4" (4.75 mm to 19.00 mm) Sand Coarse.............. No. 10 to No. 4 (2.00 mm to 4.75 mm) Medium........... No. 40 to No. 10 (0.425 mm to 2.00 mm) Fine.................. No. 200 to No. 40 (0.075 mm to 0.425 mm) Silt........................ No. 200 (0.075 mm) to .005 mm Clay...................... < .005 mm Relative ProportionsL, M trace............................. 0 to 5% little.............................. 6 to 14% with.............................. ≥ 15% Inclusion Thicknesses lens............................... 0 to 1/8" seam............................. 1/8" to 1" layer.............................. over 1" Apparent Relative Density of Cohesionless Soils Very loose ..................... 0 to 4 BPF Loose ............................ 5 to 10 BPF Medium dense.............. 11 to 30 BPF Dense............................ 31 to 50 BPF Very dense.................... over 50 BPF A. Based on the material passing the 3‐inch (75‐mm) sieve. B. If field sample contained cobbles or boulders, or both, add "with cobbles or boulders, or both" to group name. C. Gravels with 5 to 12% fines require dual symbols: GW‐GM well‐graded gravel with silt GW‐GC well‐graded gravel with clay GP‐GM poorly graded gravel with silt GP‐GC poorly graded gravel with clay D. Cu = D60 / D10 Cc = 𝐷30 2 / ሺ𝐷10 𝑥 𝐷60) E. If soil contains ≥ 15% sand, add "with sand" to group name. F. If fines classify as CL‐ML, use dual symbol GC‐GM or SC‐SM. G. If fines are organic, add "with organic fines" to group name. H. Sands with 5 to 12% fines require dual symbols: SW‐SM well‐graded sand with silt SW‐SC well‐graded sand with clay SP‐SM poorly graded sand with silt SP‐SC poorly graded sand with clay I. If soil contains ≥ 15% gravel, add "with gravel" to group name. J. If Atterberg limits plot in hatched area, soil is CL‐ML, silty clay. K. If soil contains 15 to < 30% plus No. 200, add "with sand" or "with gravel", whichever is predominant. L. If soil contains ≥ 30% plus No. 200, predominantly sand, add “sandy” to group name. M. If soil contains ≥ 30% plus No. 200 predominantly gravel, add “gravelly” to group name. N. PI ≥ 4 and plots on or above “A” line. O. PI < 4 or plots below “A” line. P. PI plots on or above “A” line. Q. PI plots below “A” line. Laboratory Tests DD Dry density,pcf qp Pocket penetrometer strength, tsf WD Wet density, pcf qU Unconfined compression test, tsf P200 % Passing #200 sieve LL Liquid limit MC Moisture content, %PL Plastic limit OC Organic content, %PI Plasticity index Consistency of Blows Approximate Unconfined Cohesive Soils Per Foot Compressive Strength Very soft................... 0 to 1 BPF................... < 0.25 tsf Soft........................... 2 to 4 BPF................... 0.25 to 0.5 tsf Medium.................... 5to 8 BPF .................. 0.5 to 1 tsf Stiff........................... 9 to 15 BPF................. 1 to 2 tsf Very Stiff................... 16 to 30 BPF............... 2 to 4 tsf Hard.......................... over 30 BPF................ > 4 tsf Drilling Notes: Blows/N‐value: Blows indicatethe driving resistance recorded for each 6‐inch interval. The reported N‐value is the blows per foot recorded by summing the second and third interval in accordance with the Standard Penetration Test, ASTM D1586. PartialPenetration:If the sampler could not be driven through a full 6‐inch interval, the number of blows for that partial penetration is shown as #/x" (i.e. 50/2"). The N‐value is reported as "REF" indicating refusal. Recovery: Indicates the inches of sample recovered from the sampled interval. For a standard penetration test, full recovery is 18", and is 24" for a thinwall/shelby tube sample. WOH: Indicates the sampler penetrated soil under weight of hammer and rods alone; driving not required. WOR: Indicates the sampler penetrated soil under weight of rods alone; hammer weight and driving not required. Water Level: Indicates the water level measured by the drillers either while drilling ( ), at the end of drilling ( ), or at some time after drilling ( ). Moisture Content: Dry:Absence of moisture, dusty, dry to the touch. Moist: Damp but no visible water. Wet: Visible free water, usually soil is below water table. 5/2021