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Hydrologic and Hydraulic Study
Stormwater Management Hydrologic and Hydraulic Study Glaccum Property Chanhassen, MN Preliminary June 5, 2015 Glaccum Property Hydrologic and Hydraulic Study June 5, 2015 Alliant Engineering, Inc. Page 1 of 4 215-0030 Introduction Included in this report are the materials necessary to review the stormwater management plan for the proposed Glaccum Property project in Chanhassen, Minnesota. The following information is included: Study Narrative Drainage Area Maps Rate Control HydroCAD Calculation Reports Volume and Water Quality Control Calculations Storm Sewer Design Calculations Background This study was conducted to analyze stormwater treatment requirements for a proposed 4 lot residential in Chanhassen, Minnesota and within Minnehaha Creek Watershed boundary. The study will show that the proposed stormwater management facility will nullify the effects of the increased impervious surface resulting from the new development. Following two scenarios are assumed in this study: Existing conditions – Minimal development Proposed conditions – Development of the residential project A complete storm water analysis of the 3.16 acre site (1.9 acres disturbed) is included in the study as well as the inclusion of 9.12 acres of offsite catchment that will affect or is affected by the site. The proposed site is bound by Lake Lucy Road to the south, Yosemite Avenue to the west, existing residential to the east and a wetland to the north. Developer is proposing 4 lot single family homes. Drainage maps provided show delineations based on full development. Stormwater management plan for the proposed conditions will meet the guidelines as required by the City of Chanhassen and Minnehaha Creek Watershed District for stormwater quantity and quality. The following criterion was used in designing the stormwater management system: Post-development peak runoff rate from the site for the 1, 2, 10, 100-year and a 100-year back to back 24-hour Type II storm events (Atlas-14) must not be greater than the existing condition rates in accordance with the City of Chanhassen and Minnehaha Creek WMC. Proposed water quality treatment must provide a minimum of 60% phosphorous and 90% total suspended solids removal per the City of Chanhassen. Stormwater management plan must meet the City and Watershed non-degradation policy for storm water runoff quality where post-development nutrient loads cannot exceed those of existing conditions. Volume control retained on site is equivalent to 1” over new impervious surface in accordance with the City of Chanhassen’s Stormwater Management Plan. Emergency overflow for flows greater than 100-year event must be provided. Runoff Rate Control All rate control calculations have been performed using the SCS method via HydroCAD software. Five events were modeled including: 1-year, 2-year, 10-year, 100-year, and 100-year back to back Type II 24-hour storm events with ATLAS-14 precipitation amounts of 2.50”, 2.87”, 4.26”, and 7.36” used, respectively. All existing and proposed curve numbers are based on an assumed soil type ‘C’ as indicated in the preliminary geotechnical investigation produced by Braun Intertec. Times of concentrations were estimated and modeled Glaccum Property Hydrologic and Hydraulic Study June 5, 2015 Alliant Engineering, Inc. Page 2 of 4 215-0030 using direct entry. The existing study does include some drainage area from offsite to the north because that area drains into the site’s drainage area. Proposed conditions watershed area will exactly match existing conditions area scenario. Existing Conditions The site is currently one lot with one single family home and associated driveway and out buildings. North side of the property is covered by Lake Lucy floodplain wetland. The wetland limits within the site were delineated Kjholhaug Environmental. The property has variable terrain that primarily drains northerly towards the wetland with a small area along the east side draining to Lake Lucy Road’s ditch. Following subcatchments were used in the existing conditions HydroCAD model: LW – Onsite area that drains to Lake Lucy Road ditch. W-1 – Onsite area that drains to the wetland. W-1(O) – Offsite area that drains across the site and ultimately to the wetland. The area will drain to the existing wetland in the existing conditions. To compare peak discharge rates for the existing and proposed conditions, flows were analyzed compositely as well as both the Lake Lucy Road ditch and Lake Lucy wetland separately. For ease of comparison, the existing analysis nodes will remain consistent in the proposed and existing models. 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: Event To Lake Lucy Road (cfs) To Wetland (cfs) Wetland NWL (ft) 1 year (2.50” 24hr) 0.73 11.58 999.36 2 year (3.87” 24hr) 0.97 15.53 999.46 10 year (4.26” 24hr) 1.98 31.98 999.90 100 year (7.36” 24hr) 4.42 72.28 1,000.89 Back to Back 100 year (7.36” 24hr) 4.42 72.28 1,001.06 Proposed Conditions The proposed development project includes construction of 4 residential lots and associated roadway as shown in the submittal plan set. Project will include construction of an underground infiltration pipe to provide the rate and volume control and water quality treatment of stormwater. Stormwater runoff from the new roadway and 3 of the front yards will be collected by storm sewer underground infiltration pipe. All of the backyards and the westerly front yard will drain uncaptured toward the wetland. Following subcatchments were used in the proposed conditions HydroCAD model: P-1 – Onsite area that drains to the wetland. P-2 – Onsite area that will be captured by storm sewer. W-1(O) – Offsite area that drains across the site and ultimately to the wetland. The area will drain directly to the existing wetland in the proposed condition. The proposed underground infiltration pipe discharge will be routed to the Lake Lucy wetland at the wetland edge. The flow will be regulated by an outlet control structure that will discharge via a 12” pipe. Refer to the submittal plan set for details on the Outlet Control Structure. The proposed stormwater management plan does increase the peak discharge rate into the wetland but because the normal water elevations are insignificantly affected, and runoff to Lake Lucy Road ditch is eliminated, there is no runoff from the site. Refer to the proposed conditions drainage map and HydroCAD report sheets for additional information. Glaccum Property Hydrologic and Hydraulic Study June 5, 2015 Alliant Engineering, Inc. Page 3 of 4 215-0030 Site composite proposed runoff rate as calculated by HydroCAD are listed in the table below: Event To Lake Lucy Road (cfs) / (∆ from Ex.) To Wetland (cfs) / (∆ from Ex.) Wetland NWL (ft) 1 year (2.50” 24hr) 0 / (-0.73) 12.66 / (1.08) 999.38 2 year (3.87” 24hr) 0 / (-0.97) 16.68 / (1.15) 999.49 10 year (4.26” 24hr) 0 / (-1.98) 33.22 / (1.24) 999.93 100 year (7.36” 24hr) 0 / (-4.42) 73.01 / (0.73) 1,000.90 Back to Back 100 year (7.36” 24hr) 0 / (-4.42) 73.01 / (0.73) 1,001.06 Stormwater Volume Control and Water Quality The proposed project will result in an addition of approximately 0.30 acres of new impervious surface. New impervious surface has been offset by onsite stormwater underground infiltration pipe. Volume control will be provided by infiltration of 1” over new impervious surface and excess NURP storage. The proposed stormwater management plan exceeds the volume control requirements of the City of Chanhassen’s Stormwater Management Plan. See appendix for calculations. The Proposed Underground Infiltration Pipe is also designed to meet the water quality requirements of the City of Chanhassen and will provide the required phosphorus and total suspended solids removal efficiencies. Erosion and Sediment Control Plan Refer to the Stormwater Pollution Prevention Plan (SWPPP) plan sheet for the erosion and sediment control plan for the project. Best Management Practices will be utilized to ensure proper erosion and sediment control. Conclusion Alliant Engineering believes that the proposed design is acceptable for all parties involved. Peak discharge rates for the 1-year, 2-year, 10-year, 100-year and 100-year back to back 24-hour storm events will be decreased from existing rates for the proposed conditions. Adequate runoff volume has been retained on site to mitigate the proposed impervious surface additions. The proposed underground infiltration designs also exceed the required amount of permanent pool volume and meet criteria for proper treatment of the runoff. Nutrient loading to receiving waters will not increase from the existing conditions and the proposed pond phosphorous removal efficiencies meet requirements. Finally, the proposed grading and SWPP plans will utilizes Best Management Practices whenever possible to provide adequate erosion control measures to contain sediment during construction. Please call me at 612-767-9362 with any questions or comments regarding stormwater issues for the Glaccum Property project. Sincerely, Pavel Nikolov, EIT Alliant Engineering, Inc. CC: File 150030 Pond 1.0” Runoff Volume Dead Pool Volume Provided Underground Infiltration Pipe 0.025 af 1,106 cf 0.027 af 1,166 cf Glaccum Property Hydrologic and Hydraulic Study June 5, 2015 Alliant Engineering, Inc. Page 4 of 4 215-0030 APPENDIX - Drainage Maps Existing Conditions Proposed Conditions - Rate Control HydroCAD Reports Existing Conditions Proposed Conditions - Precipitation Frequency Data - Water Quality and Volume Calculations Summary Spreadsheet - Storm Sewer Sizing Sizing Spreadsheet - Preliminary Geotechnical Investigation 1S LW 3S W-1 4S W-1(O) 2P W-1 5L TOTAL Routing Diagram for edrn Prepared by Alliant Engineering, Printed 6/4/2015 HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Subcat Reach Pond Link edrn Printed 6/4/2015Prepared by Alliant Engineering Page 2HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Area Listing (all nodes) Area (acres) CN Description (subcatchment-numbers) 3.336 74 >75% Grass cover, Good, HSG C (1S, 3S, 4S) 0.089 89 Gravel roads, HSG C (4S) 0.040 96 Gravel surface, HSG C (1S) 0.068 98 Impervious (1S) 0.315 98 Roofs, HSG C (3S) 0.862 98 Unconnected pavement, HSG C (4S) 1.662 98 Water Surface, 0% imp, HSG C (4S) 0.449 98 Water Surface, HSG C (3S) 5.454 70 Woods, Good, HSG C (1S, 3S, 4S) 12.275 79 TOTAL AREA Type II 24-hr 1 yr Rainfall=2.50"edrn Printed 6/4/2015Prepared by Alliant Engineering Page 3HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: LW Runoff = 0.73 cfs @ 12.00 hrs, Volume= 0.037 af, Depth= 0.79" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-30.00 hrs, dt= 0.05 hrs Type II 24-hr 1 yr Rainfall=2.50" Area (sf) CN Description 4,947 70 Woods, Good, HSG C * 2,979 98 Impervious 1,756 96 Gravel surface, HSG C 15,094 74 >75% Grass cover, Good, HSG C 24,776 78 Weighted Average 21,797 87.98% Pervious Area 2,979 12.02% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 7.6 260 0.0231 0.57 Lag/CN Method, Summary for Subcatchment 3S: W-1 Runoff = 3.35 cfs @ 12.01 hrs, Volume= 0.181 af, Depth= 0.84" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-30.00 hrs, dt= 0.05 hrs Type II 24-hr 1 yr Rainfall=2.50" Area (sf) CN Description 70,044 70 Woods, Good, HSG C 19,558 98 Water Surface, HSG C 13,721 98 Roofs, HSG C 9,540 74 >75% Grass cover, Good, HSG C 112,863 79 Weighted Average 79,584 70.51% Pervious Area 33,279 29.49% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 9.0 Direct Entry, Summary for Subcatchment 4S: W-1(O) Runoff = 8.81 cfs @ 12.08 hrs, Volume= 0.598 af, Depth= 0.79" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-30.00 hrs, dt= 0.05 hrs Type II 24-hr 1 yr Rainfall=2.50" Type II 24-hr 1 yr Rainfall=2.50"edrn Printed 6/4/2015Prepared by Alliant Engineering Page 4HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Area (sf) CN Adj Description 162,566 70 Woods, Good, HSG C 72,397 98 Water Surface, 0% imp, HSG C 37,549 98 Unconnected pavement, HSG C 120,661 74 >75% Grass cover, Good, HSG C 3,877 89 Gravel roads, HSG C 397,050 79 78 Weighted Average, UI Adjusted 359,501 90.54% Pervious Area 37,549 9.46% Impervious Area 37,549 100.00% Unconnected Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 15.0 Direct Entry, Summary for Pond 2P: W-1 Inflow Area = 11.706 ac, 13.89% Impervious, Inflow Depth = 0.80" for 1 yr event Inflow = 11.58 cfs @ 12.06 hrs, Volume= 0.779 af Outflow = 0.00 cfs @ 5.00 hrs, Volume= 0.000 af, Atten= 100%, Lag= 0.0 min Primary = 0.00 cfs @ 5.00 hrs, Volume= 0.000 af Routing by Stor-Ind method, Time Span= 5.00-30.00 hrs, dt= 0.05 hrs Starting Elev= 999.00' Surf.Area= 92,936 sf Storage= 220,377 cf Peak Elev= 999.36' @ 24.90 hrs Surf.Area= 97,995 sf Storage= 254,302 cf (33,925 cf above start) Plug-Flow detention time= (not calculated: initial storage exceeds outflow) Center-of-Mass det. time= (not calculated: no outflow) Volume Invert Avail.Storage Storage Description #1 996.00' 1,506,240 cf Custom Stage Data (Irregular) Listed below (Recalc) Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft) 996.00 55,574 937.1 0 0 55,574 1,000.00 107,513 2,029.6 320,513 320,513 313,562 1,002.00 155,414 1,946.5 261,460 581,973 340,155 1,004.00 180,253 1,931.4 335,360 917,333 346,217 1,006.00 202,937 1,997.4 382,966 1,300,299 367,222 1,007.00 208,958 2,016.1 205,940 1,506,240 373,523 Device Routing Invert Outlet Devices #1 Primary 1,006.00'123.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) Primary OutFlow Max=0.00 cfs @ 5.00 hrs HW=999.00' (Free Discharge) 1=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs) Type II 24-hr 1 yr Rainfall=2.50"edrn Printed 6/4/2015Prepared by Alliant Engineering Page 5HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Summary for Link 5L: TOTAL Inflow Area = 12.275 ac, 13.80% Impervious, Inflow Depth = 0.04" for 1 yr event Inflow = 0.73 cfs @ 12.00 hrs, Volume= 0.037 af Primary = 0.73 cfs @ 12.00 hrs, Volume= 0.037 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-30.00 hrs, dt= 0.05 hrs Type II 24-hr 2 yr Rainfall=2.87"edrn Printed 6/4/2015Prepared by Alliant Engineering Page 6HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: LW Runoff = 0.97 cfs @ 12.00 hrs, Volume= 0.049 af, Depth= 1.04" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-30.00 hrs, dt= 0.05 hrs Type II 24-hr 2 yr Rainfall=2.87" Area (sf) CN Description 4,947 70 Woods, Good, HSG C * 2,979 98 Impervious 1,756 96 Gravel surface, HSG C 15,094 74 >75% Grass cover, Good, HSG C 24,776 78 Weighted Average 21,797 87.98% Pervious Area 2,979 12.02% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 7.6 260 0.0231 0.57 Lag/CN Method, Summary for Subcatchment 3S: W-1 Runoff = 4.43 cfs @ 12.01 hrs, Volume= 0.236 af, Depth= 1.09" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-30.00 hrs, dt= 0.05 hrs Type II 24-hr 2 yr Rainfall=2.87" Area (sf) CN Description 70,044 70 Woods, Good, HSG C 19,558 98 Water Surface, HSG C 13,721 98 Roofs, HSG C 9,540 74 >75% Grass cover, Good, HSG C 112,863 79 Weighted Average 79,584 70.51% Pervious Area 33,279 29.49% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 9.0 Direct Entry, Summary for Subcatchment 4S: W-1(O) Runoff = 11.83 cfs @ 12.08 hrs, Volume= 0.788 af, Depth= 1.04" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-30.00 hrs, dt= 0.05 hrs Type II 24-hr 2 yr Rainfall=2.87" Type II 24-hr 2 yr Rainfall=2.87"edrn Printed 6/4/2015Prepared by Alliant Engineering Page 7HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Area (sf) CN Adj Description 162,566 70 Woods, Good, HSG C 72,397 98 Water Surface, 0% imp, HSG C 37,549 98 Unconnected pavement, HSG C 120,661 74 >75% Grass cover, Good, HSG C 3,877 89 Gravel roads, HSG C 397,050 79 78 Weighted Average, UI Adjusted 359,501 90.54% Pervious Area 37,549 9.46% Impervious Area 37,549 100.00% Unconnected Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 15.0 Direct Entry, Summary for Pond 2P: W-1 Inflow Area = 11.706 ac, 13.89% Impervious, Inflow Depth = 1.05" for 2 yr event Inflow = 15.53 cfs @ 12.06 hrs, Volume= 1.024 af Outflow = 0.00 cfs @ 5.00 hrs, Volume= 0.000 af, Atten= 100%, Lag= 0.0 min Primary = 0.00 cfs @ 5.00 hrs, Volume= 0.000 af Routing by Stor-Ind method, Time Span= 5.00-30.00 hrs, dt= 0.05 hrs Starting Elev= 999.00' Surf.Area= 92,936 sf Storage= 220,377 cf Peak Elev= 999.46' @ 24.90 hrs Surf.Area= 99,559 sf Storage= 264,966 cf (44,589 cf above start) Plug-Flow detention time= (not calculated: initial storage exceeds outflow) Center-of-Mass det. time= (not calculated: no outflow) Volume Invert Avail.Storage Storage Description #1 996.00' 1,506,240 cf Custom Stage Data (Irregular) Listed below (Recalc) Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft) 996.00 55,574 937.1 0 0 55,574 1,000.00 107,513 2,029.6 320,513 320,513 313,562 1,002.00 155,414 1,946.5 261,460 581,973 340,155 1,004.00 180,253 1,931.4 335,360 917,333 346,217 1,006.00 202,937 1,997.4 382,966 1,300,299 367,222 1,007.00 208,958 2,016.1 205,940 1,506,240 373,523 Device Routing Invert Outlet Devices #1 Primary 1,006.00'123.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) Primary OutFlow Max=0.00 cfs @ 5.00 hrs HW=999.00' (Free Discharge) 1=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs) Type II 24-hr 2 yr Rainfall=2.87"edrn Printed 6/4/2015Prepared by Alliant Engineering Page 8HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Summary for Link 5L: TOTAL Inflow Area = 12.275 ac, 13.80% Impervious, Inflow Depth = 0.05" for 2 yr event Inflow = 0.97 cfs @ 12.00 hrs, Volume= 0.049 af Primary = 0.97 cfs @ 12.00 hrs, Volume= 0.049 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-30.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr Rainfall=4.26"edrn Printed 6/4/2015Prepared by Alliant Engineering Page 9HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: LW Runoff = 1.98 cfs @ 11.99 hrs, Volume= 0.099 af, Depth= 2.10" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-30.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr Rainfall=4.26" Area (sf) CN Description 4,947 70 Woods, Good, HSG C * 2,979 98 Impervious 1,756 96 Gravel surface, HSG C 15,094 74 >75% Grass cover, Good, HSG C 24,776 78 Weighted Average 21,797 87.98% Pervious Area 2,979 12.02% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 7.6 260 0.0231 0.57 Lag/CN Method, Summary for Subcatchment 3S: W-1 Runoff = 8.88 cfs @ 12.01 hrs, Volume= 0.470 af, Depth= 2.18" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-30.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr Rainfall=4.26" Area (sf) CN Description 70,044 70 Woods, Good, HSG C 19,558 98 Water Surface, HSG C 13,721 98 Roofs, HSG C 9,540 74 >75% Grass cover, Good, HSG C 112,863 79 Weighted Average 79,584 70.51% Pervious Area 33,279 29.49% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 9.0 Direct Entry, Summary for Subcatchment 4S: W-1(O) Runoff = 24.51 cfs @ 12.07 hrs, Volume= 1.592 af, Depth= 2.10" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-30.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr Rainfall=4.26" Type II 24-hr 10 yr Rainfall=4.26"edrn Printed 6/4/2015Prepared by Alliant Engineering Page 10HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Area (sf) CN Adj Description 162,566 70 Woods, Good, HSG C 72,397 98 Water Surface, 0% imp, HSG C 37,549 98 Unconnected pavement, HSG C 120,661 74 >75% Grass cover, Good, HSG C 3,877 89 Gravel roads, HSG C 397,050 79 78 Weighted Average, UI Adjusted 359,501 90.54% Pervious Area 37,549 9.46% Impervious Area 37,549 100.00% Unconnected Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 15.0 Direct Entry, Summary for Pond 2P: W-1 Inflow Area = 11.706 ac, 13.89% Impervious, Inflow Depth = 2.11" for 10 yr event Inflow = 31.98 cfs @ 12.05 hrs, Volume= 2.062 af Outflow = 0.00 cfs @ 5.00 hrs, Volume= 0.000 af, Atten= 100%, Lag= 0.0 min Primary = 0.00 cfs @ 5.00 hrs, Volume= 0.000 af Routing by Stor-Ind method, Time Span= 5.00-30.00 hrs, dt= 0.05 hrs Starting Elev= 999.00' Surf.Area= 92,936 sf Storage= 220,377 cf Peak Elev= 999.90' @ 24.90 hrs Surf.Area= 106,056 sf Storage= 310,183 cf (89,806 cf above start) Plug-Flow detention time= (not calculated: initial storage exceeds outflow) Center-of-Mass det. time= (not calculated: no outflow) Volume Invert Avail.Storage Storage Description #1 996.00' 1,506,240 cf Custom Stage Data (Irregular) Listed below (Recalc) Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft) 996.00 55,574 937.1 0 0 55,574 1,000.00 107,513 2,029.6 320,513 320,513 313,562 1,002.00 155,414 1,946.5 261,460 581,973 340,155 1,004.00 180,253 1,931.4 335,360 917,333 346,217 1,006.00 202,937 1,997.4 382,966 1,300,299 367,222 1,007.00 208,958 2,016.1 205,940 1,506,240 373,523 Device Routing Invert Outlet Devices #1 Primary 1,006.00'123.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) Primary OutFlow Max=0.00 cfs @ 5.00 hrs HW=999.00' (Free Discharge) 1=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs) Type II 24-hr 10 yr Rainfall=4.26"edrn Printed 6/4/2015Prepared by Alliant Engineering Page 11HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Summary for Link 5L: TOTAL Inflow Area = 12.275 ac, 13.80% Impervious, Inflow Depth = 0.10" for 10 yr event Inflow = 1.98 cfs @ 11.99 hrs, Volume= 0.099 af Primary = 1.98 cfs @ 11.99 hrs, Volume= 0.099 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-30.00 hrs, dt= 0.05 hrs Type II 24-hr 100 yr Rainfall=7.36"edrn Printed 6/4/2015Prepared by Alliant Engineering Page 12HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: LW Runoff = 4.42 cfs @ 11.99 hrs, Volume= 0.228 af, Depth= 4.80" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-30.00 hrs, dt= 0.05 hrs Type II 24-hr 100 yr Rainfall=7.36" Area (sf) CN Description 4,947 70 Woods, Good, HSG C * 2,979 98 Impervious 1,756 96 Gravel surface, HSG C 15,094 74 >75% Grass cover, Good, HSG C 24,776 78 Weighted Average 21,797 87.98% Pervious Area 2,979 12.02% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 7.6 260 0.0231 0.57 Lag/CN Method, Summary for Subcatchment 3S: W-1 Runoff = 19.61 cfs @ 12.00 hrs, Volume= 1.061 af, Depth= 4.91" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-30.00 hrs, dt= 0.05 hrs Type II 24-hr 100 yr Rainfall=7.36" Area (sf) CN Description 70,044 70 Woods, Good, HSG C 19,558 98 Water Surface, HSG C 13,721 98 Roofs, HSG C 9,540 74 >75% Grass cover, Good, HSG C 112,863 79 Weighted Average 79,584 70.51% Pervious Area 33,279 29.49% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 9.0 Direct Entry, Summary for Subcatchment 4S: W-1(O) Runoff = 55.66 cfs @ 12.07 hrs, Volume= 3.648 af, Depth= 4.80" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-30.00 hrs, dt= 0.05 hrs Type II 24-hr 100 yr Rainfall=7.36" Type II 24-hr 100 yr Rainfall=7.36"edrn Printed 6/4/2015Prepared by Alliant Engineering Page 13HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Area (sf) CN Adj Description 162,566 70 Woods, Good, HSG C 72,397 98 Water Surface, 0% imp, HSG C 37,549 98 Unconnected pavement, HSG C 120,661 74 >75% Grass cover, Good, HSG C 3,877 89 Gravel roads, HSG C 397,050 79 78 Weighted Average, UI Adjusted 359,501 90.54% Pervious Area 37,549 9.46% Impervious Area 37,549 100.00% Unconnected Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 15.0 Direct Entry, Summary for Pond 2P: W-1 Inflow Area = 11.706 ac, 13.89% Impervious, Inflow Depth = 4.83" for 100 yr event Inflow = 72.28 cfs @ 12.05 hrs, Volume= 4.709 af Outflow = 0.00 cfs @ 5.00 hrs, Volume= 0.000 af, Atten= 100%, Lag= 0.0 min Primary = 0.00 cfs @ 5.00 hrs, Volume= 0.000 af Routing by Stor-Ind method, Time Span= 5.00-30.00 hrs, dt= 0.05 hrs Starting Elev= 999.00' Surf.Area= 92,936 sf Storage= 220,377 cf Peak Elev= 1,000.89' @ 24.90 hrs Surf.Area= 127,817 sf Storage= 425,475 cf (205,098 cf above start) Plug-Flow detention time= (not calculated: initial storage exceeds outflow) Center-of-Mass det. time= (not calculated: no outflow) Volume Invert Avail.Storage Storage Description #1 996.00' 1,506,240 cf Custom Stage Data (Irregular) Listed below (Recalc) Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft) 996.00 55,574 937.1 0 0 55,574 1,000.00 107,513 2,029.6 320,513 320,513 313,562 1,002.00 155,414 1,946.5 261,460 581,973 340,155 1,004.00 180,253 1,931.4 335,360 917,333 346,217 1,006.00 202,937 1,997.4 382,966 1,300,299 367,222 1,007.00 208,958 2,016.1 205,940 1,506,240 373,523 Device Routing Invert Outlet Devices #1 Primary 1,006.00'123.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) Primary OutFlow Max=0.00 cfs @ 5.00 hrs HW=999.00' (Free Discharge) 1=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs) Type II 24-hr 100 yr Rainfall=7.36"edrn Printed 6/4/2015Prepared by Alliant Engineering Page 14HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Summary for Link 5L: TOTAL Inflow Area = 12.275 ac, 13.80% Impervious, Inflow Depth = 0.22" for 100 yr event Inflow = 4.42 cfs @ 11.99 hrs, Volume= 0.228 af Primary = 4.42 cfs @ 11.99 hrs, Volume= 0.228 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-30.00 hrs, dt= 0.05 hrs Type II 24-hr Bk-Bk 100 yr Rainfall=7.36" x 2edrn Printed 6/4/2015Prepared by Alliant Engineering Page 15HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: LW Runoff = 4.42 cfs @ 11.99 hrs, Volume= 0.253 af, Depth> 5.33" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-30.00 hrs, dt= 0.05 hrs Type II 24-hr Bk-Bk 100 yr Rainfall=7.36" x 2 Area (sf) CN Description 4,947 70 Woods, Good, HSG C * 2,979 98 Impervious 1,756 96 Gravel surface, HSG C 15,094 74 >75% Grass cover, Good, HSG C 24,776 78 Weighted Average 21,797 87.98% Pervious Area 2,979 12.02% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 7.6 260 0.0231 0.57 Lag/CN Method, Summary for Subcatchment 3S: W-1 Runoff = 19.61 cfs @ 12.00 hrs, Volume= 1.176 af, Depth> 5.45" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-30.00 hrs, dt= 0.05 hrs Type II 24-hr Bk-Bk 100 yr Rainfall=7.36" x 2 Area (sf) CN Description 70,044 70 Woods, Good, HSG C 19,558 98 Water Surface, HSG C 13,721 98 Roofs, HSG C 9,540 74 >75% Grass cover, Good, HSG C 112,863 79 Weighted Average 79,584 70.51% Pervious Area 33,279 29.49% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 9.0 Direct Entry, Summary for Subcatchment 4S: W-1(O) Runoff = 55.66 cfs @ 12.07 hrs, Volume= 4.040 af, Depth> 5.32" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-30.00 hrs, dt= 0.05 hrs Type II 24-hr Bk-Bk 100 yr Rainfall=7.36" x 2 Type II 24-hr Bk-Bk 100 yr Rainfall=7.36" x 2edrn Printed 6/4/2015Prepared by Alliant Engineering Page 16HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Area (sf) CN Adj Description 162,566 70 Woods, Good, HSG C 72,397 98 Water Surface, 0% imp, HSG C 37,549 98 Unconnected pavement, HSG C 120,661 74 >75% Grass cover, Good, HSG C 3,877 89 Gravel roads, HSG C 397,050 79 78 Weighted Average, UI Adjusted 359,501 90.54% Pervious Area 37,549 9.46% Impervious Area 37,549 100.00% Unconnected Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 15.0 Direct Entry, Summary for Pond 2P: W-1 Inflow Area = 11.706 ac, 13.89% Impervious, Inflow Depth > 5.35" for Bk-Bk 100 yr event Inflow = 72.28 cfs @ 12.05 hrs, Volume= 5.216 af Outflow = 0.00 cfs @ 5.00 hrs, Volume= 0.000 af, Atten= 100%, Lag= 0.0 min Primary = 0.00 cfs @ 5.00 hrs, Volume= 0.000 af Routing by Stor-Ind method, Time Span= 5.00-30.00 hrs, dt= 0.05 hrs Starting Elev= 999.00' Surf.Area= 92,936 sf Storage= 220,377 cf Peak Elev= 1,001.06' @ 30.00 hrs Surf.Area= 131,863 sf Storage= 447,456 cf (227,079 cf above start) Plug-Flow detention time= (not calculated: initial storage exceeds outflow) Center-of-Mass det. time= (not calculated: no outflow) Volume Invert Avail.Storage Storage Description #1 996.00' 1,506,240 cf Custom Stage Data (Irregular) Listed below (Recalc) Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft) 996.00 55,574 937.1 0 0 55,574 1,000.00 107,513 2,029.6 320,513 320,513 313,562 1,002.00 155,414 1,946.5 261,460 581,973 340,155 1,004.00 180,253 1,931.4 335,360 917,333 346,217 1,006.00 202,937 1,997.4 382,966 1,300,299 367,222 1,007.00 208,958 2,016.1 205,940 1,506,240 373,523 Device Routing Invert Outlet Devices #1 Primary 1,006.00'123.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) Primary OutFlow Max=0.00 cfs @ 5.00 hrs HW=999.00' (Free Discharge) 1=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs) Type II 24-hr Bk-Bk 100 yr Rainfall=7.36" x 2edrn Printed 6/4/2015Prepared by Alliant Engineering Page 17HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Summary for Link 5L: TOTAL Inflow Area = 12.275 ac, 13.80% Impervious, Inflow Depth > 0.25" for Bk-Bk 100 yr event Inflow = 4.42 cfs @ 11.99 hrs, Volume= 0.253 af Primary = 4.42 cfs @ 11.99 hrs, Volume= 0.253 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-30.00 hrs, dt= 0.05 hrs 1S P-1 2S P-2 4S W-1(O) 3P W-1 7P Storage Pipe 6L TOTAL Routing Diagram for pdrn Prepared by Alliant Engineering, Printed 6/4/2015 HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Subcat Reach Pond Link pdrn Printed 6/4/2015Prepared by Alliant Engineering Page 2HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Area Listing (all nodes) Area (acres) CN Description (subcatchment-numbers) 3.711 74 >75% Grass cover, Good, HSG C (1S, 2S, 4S) 0.089 96 Gravel surface, HSG C (4S) 1.830 98 Impervious (1S, 2S, 4S) 0.449 98 Water Surface, 0% imp, HSG C (1S) 1.662 98 Water Surface, HSG C (4S) 4.534 70 Woods, Good, HSG C (1S, 2S, 4S) 12.275 80 TOTAL AREA Type II 24-hr 1 yr Rainfall=2.50"pdrn Printed 6/4/2015Prepared by Alliant Engineering Page 3HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: P-1 Runoff = 3.59 cfs @ 12.02 hrs, Volume= 0.195 af, Depth= 1.06" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type II 24-hr 1 yr Rainfall=2.50" Area (sf) CN Description 23,479 70 Woods, Good, HSG C * 22,390 98 Impervious 30,884 74 >75% Grass cover, Good, HSG C 19,558 98 Water Surface, 0% imp, HSG C 96,311 83 Weighted Average 73,921 76.75% Pervious Area 22,390 23.25% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.0 Direct Entry, Summary for Subcatchment 2S: P-2 Runoff = 1.83 cfs @ 11.99 hrs, Volume= 0.088 af, Depth= 1.12" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type II 24-hr 1 yr Rainfall=2.50" Area (ac) CN Description 0.263 70 Woods, Good, HSG C * 0.454 98 Impervious 0.232 74 >75% Grass cover, Good, HSG C 0.949 84 Weighted Average 0.495 52.16% Pervious Area 0.454 47.84% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 7.0 Direct Entry, Summary for Subcatchment 4S: W-1(O) Runoff = 9.57 cfs @ 12.08 hrs, Volume= 0.636 af, Depth= 0.84" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type II 24-hr 1 yr Rainfall=2.50" Type II 24-hr 1 yr Rainfall=2.50"pdrn Printed 6/4/2015Prepared by Alliant Engineering Page 4HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Area (sf) CN Description 162,566 70 Woods, Good, HSG C 72,397 98 Water Surface, HSG C * 37,549 98 Impervious 120,661 74 >75% Grass cover, Good, HSG C 3,877 96 Gravel surface, HSG C 397,050 79 Weighted Average 287,104 72.31% Pervious Area 109,946 27.69% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 15.0 Direct Entry, Summary for Pond 3P: W-1 Inflow Area = 12.275 ac, 28.45% Impervious, Inflow Depth = 0.81" for 1 yr event Inflow = 12.66 cfs @ 12.06 hrs, Volume= 0.831 af Outflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Atten= 100%, Lag= 0.0 min Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af Routing by Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Starting Elev= 999.00' Surf.Area= 92,936 sf Storage= 220,377 cf Peak Elev= 999.38' @ 24.84 hrs Surf.Area= 98,325 sf Storage= 256,541 cf (36,164 cf above start) Plug-Flow detention time= (not calculated: initial storage exceeds outflow) Center-of-Mass det. time= (not calculated: no outflow) Volume Invert Avail.Storage Storage Description #1 996.00' 1,506,240 cf Custom Stage Data (Irregular) Listed below (Recalc) Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft) 996.00 55,574 937.1 0 0 55,574 1,000.00 107,513 2,029.6 320,513 320,513 313,562 1,002.00 155,414 1,946.5 261,460 581,973 340,155 1,004.00 180,253 1,931.4 335,360 917,333 346,217 1,006.00 202,937 1,997.4 382,966 1,300,299 367,222 1,007.00 208,958 2,016.1 205,940 1,506,240 373,523 Device Routing Invert Outlet Devices #1 Primary 1,006.00'123.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=999.00' (Free Discharge) 1=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs) Type II 24-hr 1 yr Rainfall=2.50"pdrn Printed 6/4/2015Prepared by Alliant Engineering Page 5HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Summary for Pond 7P: Storage Pipe Inflow Area = 0.949 ac, 47.84% Impervious, Inflow Depth = 1.12" for 1 yr event Inflow = 1.83 cfs @ 11.99 hrs, Volume= 0.088 af Outflow = 0.02 cfs @ 11.85 hrs, Volume= 0.029 af, Atten= 99%, Lag= 0.0 min Discarded = 0.02 cfs @ 11.85 hrs, Volume= 0.029 af Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af Routing by Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Peak Elev= 1,013.73' @ 24.05 hrs Surf.Area= 4,072 sf Storage= 2,990 cf Plug-Flow detention time= 538.7 min calculated for 0.029 af (33% of inflow) Center-of-Mass det. time= 406.4 min ( 1,245.5 - 839.1 ) Volume Invert Avail.Storage Storage Description #1 1,016.00' 942 cf 48.0" Round Pipe Storage Inside #2 L= 75.0' #2 1,015.50' 224 cf 5.00'W x 75.00'L x 4.50'H Rock Bedding 1,688 cf Overall - 942 cf Embedded = 745 cf x 30.0% Voids #3 1,013.00' 44,787 cf 72.00'D x 11.00'H Vertical Cone/Cylinder 45,953 cf Total Available Storage Device Routing Invert Outlet Devices #1 Primary 1,003.00'12.0" Round Culvert L= 40.0' RCP, rounded edge headwall, Ke= 0.100 Inlet / Outlet Invert= 1,003.00' / 1,002.00' S= 0.0250 '/' Cc= 0.900 n= 0.013, Flow Area= 0.79 sf #2 Device 1 1,020.00'12.0" Round Culvert L= 50.2' RCP, rounded edge headwall, Ke= 0.100 Inlet / Outlet Invert= 1,020.00' / 1,009.00' S= 0.2191 '/' Cc= 0.900 n= 0.013, Flow Area= 0.79 sf #3 Discarded 1,013.00'0.200 in/hr Exfiltration over Surface area Phase-In= 0.01' Discarded OutFlow Max=0.02 cfs @ 11.85 hrs HW=1,013.11' (Free Discharge) 3=Exfiltration (Exfiltration Controls 0.02 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=1,013.00' (Free Discharge) 1=Culvert (Passes 0.00 cfs of 12.99 cfs potential flow) 2=Culvert ( Controls 0.00 cfs) Summary for Link 6L: TOTAL Inflow Area = 12.275 ac, 28.45% Impervious, Inflow Depth = 0.00" for 1 yr event Inflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type II 24-hr 2 yr Rainfall=2.87"pdrn Printed 6/4/2015Prepared by Alliant Engineering Page 6HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: P-1 Runoff = 4.58 cfs @ 12.02 hrs, Volume= 0.247 af, Depth= 1.34" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type II 24-hr 2 yr Rainfall=2.87" Area (sf) CN Description 23,479 70 Woods, Good, HSG C * 22,390 98 Impervious 30,884 74 >75% Grass cover, Good, HSG C 19,558 98 Water Surface, 0% imp, HSG C 96,311 83 Weighted Average 73,921 76.75% Pervious Area 22,390 23.25% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.0 Direct Entry, Summary for Subcatchment 2S: P-2 Runoff = 2.31 cfs @ 11.99 hrs, Volume= 0.112 af, Depth= 1.41" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type II 24-hr 2 yr Rainfall=2.87" Area (ac) CN Description 0.263 70 Woods, Good, HSG C * 0.454 98 Impervious 0.232 74 >75% Grass cover, Good, HSG C 0.949 84 Weighted Average 0.495 52.16% Pervious Area 0.454 47.84% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 7.0 Direct Entry, Summary for Subcatchment 4S: W-1(O) Runoff = 12.72 cfs @ 12.08 hrs, Volume= 0.831 af, Depth= 1.09" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type II 24-hr 2 yr Rainfall=2.87" Type II 24-hr 2 yr Rainfall=2.87"pdrn Printed 6/4/2015Prepared by Alliant Engineering Page 7HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Area (sf) CN Description 162,566 70 Woods, Good, HSG C 72,397 98 Water Surface, HSG C * 37,549 98 Impervious 120,661 74 >75% Grass cover, Good, HSG C 3,877 96 Gravel surface, HSG C 397,050 79 Weighted Average 287,104 72.31% Pervious Area 109,946 27.69% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 15.0 Direct Entry, Summary for Pond 3P: W-1 Inflow Area = 12.275 ac, 28.45% Impervious, Inflow Depth = 1.05" for 2 yr event Inflow = 16.68 cfs @ 12.06 hrs, Volume= 1.079 af Outflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Atten= 100%, Lag= 0.0 min Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af Routing by Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Starting Elev= 999.00' Surf.Area= 92,936 sf Storage= 220,377 cf Peak Elev= 999.49' @ 24.84 hrs Surf.Area= 99,905 sf Storage= 267,343 cf (46,966 cf above start) Plug-Flow detention time= (not calculated: initial storage exceeds outflow) Center-of-Mass det. time= (not calculated: no outflow) Volume Invert Avail.Storage Storage Description #1 996.00' 1,506,240 cf Custom Stage Data (Irregular) Listed below (Recalc) Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft) 996.00 55,574 937.1 0 0 55,574 1,000.00 107,513 2,029.6 320,513 320,513 313,562 1,002.00 155,414 1,946.5 261,460 581,973 340,155 1,004.00 180,253 1,931.4 335,360 917,333 346,217 1,006.00 202,937 1,997.4 382,966 1,300,299 367,222 1,007.00 208,958 2,016.1 205,940 1,506,240 373,523 Device Routing Invert Outlet Devices #1 Primary 1,006.00'123.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=999.00' (Free Discharge) 1=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs) Type II 24-hr 2 yr Rainfall=2.87"pdrn Printed 6/4/2015Prepared by Alliant Engineering Page 8HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Summary for Pond 7P: Storage Pipe Inflow Area = 0.949 ac, 47.84% Impervious, Inflow Depth = 1.41" for 2 yr event Inflow = 2.31 cfs @ 11.99 hrs, Volume= 0.112 af Outflow = 0.02 cfs @ 11.78 hrs, Volume= 0.029 af, Atten= 99%, Lag= 0.0 min Discarded = 0.02 cfs @ 11.78 hrs, Volume= 0.029 af Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af Routing by Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Peak Elev= 1,013.98' @ 24.07 hrs Surf.Area= 4,072 sf Storage= 3,985 cf Plug-Flow detention time= 538.8 min calculated for 0.029 af (26% of inflow) Center-of-Mass det. time= 405.3 min ( 1,237.7 - 832.4 ) Volume Invert Avail.Storage Storage Description #1 1,016.00' 942 cf 48.0" Round Pipe Storage Inside #2 L= 75.0' #2 1,015.50' 224 cf 5.00'W x 75.00'L x 4.50'H Rock Bedding 1,688 cf Overall - 942 cf Embedded = 745 cf x 30.0% Voids #3 1,013.00' 44,787 cf 72.00'D x 11.00'H Vertical Cone/Cylinder 45,953 cf Total Available Storage Device Routing Invert Outlet Devices #1 Primary 1,003.00'12.0" Round Culvert L= 40.0' RCP, rounded edge headwall, Ke= 0.100 Inlet / Outlet Invert= 1,003.00' / 1,002.00' S= 0.0250 '/' Cc= 0.900 n= 0.013, Flow Area= 0.79 sf #2 Device 1 1,020.00'12.0" Round Culvert L= 50.2' RCP, rounded edge headwall, Ke= 0.100 Inlet / Outlet Invert= 1,020.00' / 1,009.00' S= 0.2191 '/' Cc= 0.900 n= 0.013, Flow Area= 0.79 sf #3 Discarded 1,013.00'0.200 in/hr Exfiltration over Surface area Phase-In= 0.01' Discarded OutFlow Max=0.02 cfs @ 11.78 hrs HW=1,013.11' (Free Discharge) 3=Exfiltration (Exfiltration Controls 0.02 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=1,013.00' (Free Discharge) 1=Culvert (Passes 0.00 cfs of 12.99 cfs potential flow) 2=Culvert ( Controls 0.00 cfs) Summary for Link 6L: TOTAL Inflow Area = 12.275 ac, 28.45% Impervious, Inflow Depth = 0.00" for 2 yr event Inflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type II 24-hr 10 yr Rainfall=4.26"pdrn Printed 6/4/2015Prepared by Alliant Engineering Page 9HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: P-1 Runoff = 8.50 cfs @ 12.02 hrs, Volume= 0.463 af, Depth= 2.51" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type II 24-hr 10 yr Rainfall=4.26" Area (sf) CN Description 23,479 70 Woods, Good, HSG C * 22,390 98 Impervious 30,884 74 >75% Grass cover, Good, HSG C 19,558 98 Water Surface, 0% imp, HSG C 96,311 83 Weighted Average 73,921 76.75% Pervious Area 22,390 23.25% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.0 Direct Entry, Summary for Subcatchment 2S: P-2 Runoff = 4.18 cfs @ 11.98 hrs, Volume= 0.206 af, Depth= 2.60" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type II 24-hr 10 yr Rainfall=4.26" Area (ac) CN Description 0.263 70 Woods, Good, HSG C * 0.454 98 Impervious 0.232 74 >75% Grass cover, Good, HSG C 0.949 84 Weighted Average 0.495 52.16% Pervious Area 0.454 47.84% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 7.0 Direct Entry, Summary for Subcatchment 4S: W-1(O) Runoff = 25.72 cfs @ 12.07 hrs, Volume= 1.653 af, Depth= 2.18" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type II 24-hr 10 yr Rainfall=4.26" Type II 24-hr 10 yr Rainfall=4.26"pdrn Printed 6/4/2015Prepared by Alliant Engineering Page 10HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Area (sf) CN Description 162,566 70 Woods, Good, HSG C 72,397 98 Water Surface, HSG C * 37,549 98 Impervious 120,661 74 >75% Grass cover, Good, HSG C 3,877 96 Gravel surface, HSG C 397,050 79 Weighted Average 287,104 72.31% Pervious Area 109,946 27.69% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 15.0 Direct Entry, Summary for Pond 3P: W-1 Inflow Area = 12.275 ac, 28.45% Impervious, Inflow Depth = 2.07" for 10 yr event Inflow = 33.22 cfs @ 12.05 hrs, Volume= 2.116 af Outflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Atten= 100%, Lag= 0.0 min Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af Routing by Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Starting Elev= 999.00' Surf.Area= 92,936 sf Storage= 220,377 cf Peak Elev= 999.93' @ 24.84 hrs Surf.Area= 106,390 sf Storage= 312,546 cf (92,169 cf above start) Plug-Flow detention time= (not calculated: initial storage exceeds outflow) Center-of-Mass det. time= (not calculated: no outflow) Volume Invert Avail.Storage Storage Description #1 996.00' 1,506,240 cf Custom Stage Data (Irregular) Listed below (Recalc) Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft) 996.00 55,574 937.1 0 0 55,574 1,000.00 107,513 2,029.6 320,513 320,513 313,562 1,002.00 155,414 1,946.5 261,460 581,973 340,155 1,004.00 180,253 1,931.4 335,360 917,333 346,217 1,006.00 202,937 1,997.4 382,966 1,300,299 367,222 1,007.00 208,958 2,016.1 205,940 1,506,240 373,523 Device Routing Invert Outlet Devices #1 Primary 1,006.00'123.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=999.00' (Free Discharge) 1=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs) Type II 24-hr 10 yr Rainfall=4.26"pdrn Printed 6/4/2015Prepared by Alliant Engineering Page 11HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Summary for Pond 7P: Storage Pipe Inflow Area = 0.949 ac, 47.84% Impervious, Inflow Depth = 2.60" for 10 yr event Inflow = 4.18 cfs @ 11.98 hrs, Volume= 0.206 af Outflow = 0.02 cfs @ 11.11 hrs, Volume= 0.031 af, Atten= 100%, Lag= 0.0 min Discarded = 0.02 cfs @ 11.11 hrs, Volume= 0.031 af Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af Routing by Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Peak Elev= 1,014.96' @ 24.10 hrs Surf.Area= 4,072 sf Storage= 8,000 cf Plug-Flow detention time= 539.6 min calculated for 0.031 af (15% of inflow) Center-of-Mass det. time= 383.2 min ( 1,198.1 - 814.9 ) Volume Invert Avail.Storage Storage Description #1 1,016.00' 942 cf 48.0" Round Pipe Storage Inside #2 L= 75.0' #2 1,015.50' 224 cf 5.00'W x 75.00'L x 4.50'H Rock Bedding 1,688 cf Overall - 942 cf Embedded = 745 cf x 30.0% Voids #3 1,013.00' 44,787 cf 72.00'D x 11.00'H Vertical Cone/Cylinder 45,953 cf Total Available Storage Device Routing Invert Outlet Devices #1 Primary 1,003.00'12.0" Round Culvert L= 40.0' RCP, rounded edge headwall, Ke= 0.100 Inlet / Outlet Invert= 1,003.00' / 1,002.00' S= 0.0250 '/' Cc= 0.900 n= 0.013, Flow Area= 0.79 sf #2 Device 1 1,020.00'12.0" Round Culvert L= 50.2' RCP, rounded edge headwall, Ke= 0.100 Inlet / Outlet Invert= 1,020.00' / 1,009.00' S= 0.2191 '/' Cc= 0.900 n= 0.013, Flow Area= 0.79 sf #3 Discarded 1,013.00'0.200 in/hr Exfiltration over Surface area Phase-In= 0.01' Discarded OutFlow Max=0.02 cfs @ 11.11 hrs HW=1,013.11' (Free Discharge) 3=Exfiltration (Exfiltration Controls 0.02 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=1,013.00' (Free Discharge) 1=Culvert (Passes 0.00 cfs of 12.99 cfs potential flow) 2=Culvert ( Controls 0.00 cfs) Summary for Link 6L: TOTAL Inflow Area = 12.275 ac, 28.45% Impervious, Inflow Depth = 0.00" for 10 yr event Inflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type II 24-hr 100 yr Rainfall=7.36"pdrn Printed 6/4/2015Prepared by Alliant Engineering Page 12HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: P-1 Runoff = 17.60 cfs @ 12.01 hrs, Volume= 0.989 af, Depth= 5.37" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type II 24-hr 100 yr Rainfall=7.36" Area (sf) CN Description 23,479 70 Woods, Good, HSG C * 22,390 98 Impervious 30,884 74 >75% Grass cover, Good, HSG C 19,558 98 Water Surface, 0% imp, HSG C 96,311 83 Weighted Average 73,921 76.75% Pervious Area 22,390 23.25% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.0 Direct Entry, Summary for Subcatchment 2S: P-2 Runoff = 8.48 cfs @ 11.98 hrs, Volume= 0.434 af, Depth= 5.48" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type II 24-hr 100 yr Rainfall=7.36" Area (ac) CN Description 0.263 70 Woods, Good, HSG C * 0.454 98 Impervious 0.232 74 >75% Grass cover, Good, HSG C 0.949 84 Weighted Average 0.495 52.16% Pervious Area 0.454 47.84% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 7.0 Direct Entry, Summary for Subcatchment 4S: W-1(O) Runoff = 57.28 cfs @ 12.07 hrs, Volume= 3.733 af, Depth= 4.91" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type II 24-hr 100 yr Rainfall=7.36" Type II 24-hr 100 yr Rainfall=7.36"pdrn Printed 6/4/2015Prepared by Alliant Engineering Page 13HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Area (sf) CN Description 162,566 70 Woods, Good, HSG C 72,397 98 Water Surface, HSG C * 37,549 98 Impervious 120,661 74 >75% Grass cover, Good, HSG C 3,877 96 Gravel surface, HSG C 397,050 79 Weighted Average 287,104 72.31% Pervious Area 109,946 27.69% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 15.0 Direct Entry, Summary for Pond 3P: W-1 Inflow Area = 12.275 ac, 28.45% Impervious, Inflow Depth = 4.62" for 100 yr event Inflow = 73.01 cfs @ 12.05 hrs, Volume= 4.722 af Outflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Atten= 100%, Lag= 0.0 min Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af Routing by Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Starting Elev= 999.00' Surf.Area= 92,936 sf Storage= 220,377 cf Peak Elev= 1,000.90' @ 24.84 hrs Surf.Area= 127,924 sf Storage= 426,052 cf (205,675 cf above start) Plug-Flow detention time= (not calculated: initial storage exceeds outflow) Center-of-Mass det. time= (not calculated: no outflow) Volume Invert Avail.Storage Storage Description #1 996.00' 1,506,240 cf Custom Stage Data (Irregular) Listed below (Recalc) Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft) 996.00 55,574 937.1 0 0 55,574 1,000.00 107,513 2,029.6 320,513 320,513 313,562 1,002.00 155,414 1,946.5 261,460 581,973 340,155 1,004.00 180,253 1,931.4 335,360 917,333 346,217 1,006.00 202,937 1,997.4 382,966 1,300,299 367,222 1,007.00 208,958 2,016.1 205,940 1,506,240 373,523 Device Routing Invert Outlet Devices #1 Primary 1,006.00'123.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=999.00' (Free Discharge) 1=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs) Type II 24-hr 100 yr Rainfall=7.36"pdrn Printed 6/4/2015Prepared by Alliant Engineering Page 14HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Summary for Pond 7P: Storage Pipe Inflow Area = 0.949 ac, 47.84% Impervious, Inflow Depth = 5.48" for 100 yr event Inflow = 8.48 cfs @ 11.98 hrs, Volume= 0.434 af Outflow = 0.02 cfs @ 12.10 hrs, Volume= 0.038 af, Atten= 100%, Lag= 7.2 min Discarded = 0.02 cfs @ 12.10 hrs, Volume= 0.038 af Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af Routing by Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Peak Elev= 1,017.25' @ 24.13 hrs Surf.Area= 4,447 sf Storage= 17,672 cf Plug-Flow detention time= 579.8 min calculated for 0.038 af (9% of inflow) Center-of-Mass det. time= 336.2 min ( 1,130.0 - 793.8 ) Volume Invert Avail.Storage Storage Description #1 1,016.00' 942 cf 48.0" Round Pipe Storage Inside #2 L= 75.0' #2 1,015.50' 224 cf 5.00'W x 75.00'L x 4.50'H Rock Bedding 1,688 cf Overall - 942 cf Embedded = 745 cf x 30.0% Voids #3 1,013.00' 44,787 cf 72.00'D x 11.00'H Vertical Cone/Cylinder 45,953 cf Total Available Storage Device Routing Invert Outlet Devices #1 Primary 1,003.00'12.0" Round Culvert L= 40.0' RCP, rounded edge headwall, Ke= 0.100 Inlet / Outlet Invert= 1,003.00' / 1,002.00' S= 0.0250 '/' Cc= 0.900 n= 0.013, Flow Area= 0.79 sf #2 Device 1 1,020.00'12.0" Round Culvert L= 50.2' RCP, rounded edge headwall, Ke= 0.100 Inlet / Outlet Invert= 1,020.00' / 1,009.00' S= 0.2191 '/' Cc= 0.900 n= 0.013, Flow Area= 0.79 sf #3 Discarded 1,013.00'0.200 in/hr Exfiltration over Surface area Phase-In= 0.01' Discarded OutFlow Max=0.02 cfs @ 12.10 hrs HW=1,015.51' (Free Discharge) 3=Exfiltration (Exfiltration Controls 0.02 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=1,013.00' (Free Discharge) 1=Culvert (Passes 0.00 cfs of 12.99 cfs potential flow) 2=Culvert ( Controls 0.00 cfs) Summary for Link 6L: TOTAL Inflow Area = 12.275 ac, 28.45% Impervious, Inflow Depth = 0.00" for 100 yr event Inflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type II 24-hr Bk-Bk 100 yr Rainfall=7.36" x 2pdrn Printed 6/4/2015Prepared by Alliant Engineering Page 15HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: P-1 Runoff = 17.60 cfs @ 12.01 hrs, Volume= 1.089 af, Depth> 5.91" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type II 24-hr Bk-Bk 100 yr Rainfall=7.36" x 2 Area (sf) CN Description 23,479 70 Woods, Good, HSG C * 22,390 98 Impervious 30,884 74 >75% Grass cover, Good, HSG C 19,558 98 Water Surface, 0% imp, HSG C 96,311 83 Weighted Average 73,921 76.75% Pervious Area 22,390 23.25% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.0 Direct Entry, Summary for Subcatchment 2S: P-2 Runoff = 8.48 cfs @ 11.98 hrs, Volume= 0.477 af, Depth> 6.03" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type II 24-hr Bk-Bk 100 yr Rainfall=7.36" x 2 Area (ac) CN Description 0.263 70 Woods, Good, HSG C * 0.454 98 Impervious 0.232 74 >75% Grass cover, Good, HSG C 0.949 84 Weighted Average 0.495 52.16% Pervious Area 0.454 47.84% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 7.0 Direct Entry, Summary for Subcatchment 4S: W-1(O) Runoff = 57.28 cfs @ 12.07 hrs, Volume= 4.127 af, Depth> 5.43" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Type II 24-hr Bk-Bk 100 yr Rainfall=7.36" x 2 Type II 24-hr Bk-Bk 100 yr Rainfall=7.36" x 2pdrn Printed 6/4/2015Prepared by Alliant Engineering Page 16HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Area (sf) CN Description 162,566 70 Woods, Good, HSG C 72,397 98 Water Surface, HSG C * 37,549 98 Impervious 120,661 74 >75% Grass cover, Good, HSG C 3,877 96 Gravel surface, HSG C 397,050 79 Weighted Average 287,104 72.31% Pervious Area 109,946 27.69% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 15.0 Direct Entry, Summary for Pond 3P: W-1 Inflow Area = 12.275 ac, 28.45% Impervious, Inflow Depth > 5.10" for Bk-Bk 100 yr event Inflow = 73.01 cfs @ 12.05 hrs, Volume= 5.216 af Outflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Atten= 100%, Lag= 0.0 min Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af Routing by Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Starting Elev= 999.00' Surf.Area= 92,936 sf Storage= 220,377 cf Peak Elev= 1,001.06' @ 30.00 hrs Surf.Area= 131,878 sf Storage= 447,536 cf (227,159 cf above start) Plug-Flow detention time= (not calculated: initial storage exceeds outflow) Center-of-Mass det. time= (not calculated: no outflow) Volume Invert Avail.Storage Storage Description #1 996.00' 1,506,240 cf Custom Stage Data (Irregular) Listed below (Recalc) Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft) 996.00 55,574 937.1 0 0 55,574 1,000.00 107,513 2,029.6 320,513 320,513 313,562 1,002.00 155,414 1,946.5 261,460 581,973 340,155 1,004.00 180,253 1,931.4 335,360 917,333 346,217 1,006.00 202,937 1,997.4 382,966 1,300,299 367,222 1,007.00 208,958 2,016.1 205,940 1,506,240 373,523 Device Routing Invert Outlet Devices #1 Primary 1,006.00'123.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=999.00' (Free Discharge) 1=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs) Type II 24-hr Bk-Bk 100 yr Rainfall=7.36" x 2pdrn Printed 6/4/2015Prepared by Alliant Engineering Page 17HydroCAD® 10.00 s/n 01427 © 2013 HydroCAD Software Solutions LLC Summary for Pond 7P: Storage Pipe Inflow Area = 0.949 ac, 47.84% Impervious, Inflow Depth > 6.03" for Bk-Bk 100 yr event Inflow = 8.48 cfs @ 11.98 hrs, Volume= 0.477 af Outflow = 0.02 cfs @ 12.10 hrs, Volume= 0.038 af, Atten= 100%, Lag= 7.2 min Discarded = 0.02 cfs @ 12.10 hrs, Volume= 0.038 af Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af Routing by Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs Peak Elev= 1,017.58' @ 30.00 hrs Surf.Area= 4,447 sf Storage= 19,134 cf Plug-Flow detention time= 579.8 min calculated for 0.038 af (8% of inflow) Center-of-Mass det. time= 259.0 min ( 1,130.0 - 871.0 ) Volume Invert Avail.Storage Storage Description #1 1,016.00' 942 cf 48.0" Round Pipe Storage Inside #2 L= 75.0' #2 1,015.50' 224 cf 5.00'W x 75.00'L x 4.50'H Rock Bedding 1,688 cf Overall - 942 cf Embedded = 745 cf x 30.0% Voids #3 1,013.00' 44,787 cf 72.00'D x 11.00'H Vertical Cone/Cylinder 45,953 cf Total Available Storage Device Routing Invert Outlet Devices #1 Primary 1,003.00'12.0" Round Culvert L= 40.0' RCP, rounded edge headwall, Ke= 0.100 Inlet / Outlet Invert= 1,003.00' / 1,002.00' S= 0.0250 '/' Cc= 0.900 n= 0.013, Flow Area= 0.79 sf #2 Device 1 1,020.00'12.0" Round Culvert L= 50.2' RCP, rounded edge headwall, Ke= 0.100 Inlet / Outlet Invert= 1,020.00' / 1,009.00' S= 0.2191 '/' Cc= 0.900 n= 0.013, Flow Area= 0.79 sf #3 Discarded 1,013.00'0.200 in/hr Exfiltration over Surface area Phase-In= 0.01' Discarded OutFlow Max=0.02 cfs @ 12.10 hrs HW=1,015.51' (Free Discharge) 3=Exfiltration (Exfiltration Controls 0.02 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=1,013.00' (Free Discharge) 1=Culvert (Passes 0.00 cfs of 12.99 cfs potential flow) 2=Culvert ( Controls 0.00 cfs) Summary for Link 6L: TOTAL Inflow Area = 12.275 ac, 28.45% Impervious, Inflow Depth = 0.00" for Bk-Bk 100 yr event Inflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs NOAA Atlas 14, Volume 8, Version 2 Location name: Excelsior, Minnesota, US* Latitude: 44.8849°, Longitude: -93.5599° Elevation: 1065 ft* * source: Google Maps POINT PRECIPITATION FREQUENCY ESTIMATES Sanja Perica, Deborah Martin, Sandra Pavlovic, Ishani Roy, Michael St. Laurent, Carl Trypaluk, Dale Unruh, Michael Yekta, Geoffery Bonnin NOAA, National Weather Service, Silver Spring, Maryland PF_tabular | PF_graphical | Maps_&_aerials PF tabular PDS-based point precipitation frequency estimates with 90% confidence intervals (in inches)1 Duration Average recurrence interval (years) 1 2 5 10 25 50 100 200 500 1000 5-min 0.355 (0.275-0.459) 0.421 (0.326-0.545) 0.535 (0.413-0.694) 0.635 (0.488-0.827) 0.781 (0.583-1.05) 0.900 (0.656-1.22) 1.02 (0.722-1.41) 1.16 (0.782-1.62) 1.34 (0.872-1.92) 1.48 (0.940-2.14) 10-min 0.520 (0.403-0.672) 0.617 (0.477-0.798) 0.784 (0.605-1.02) 0.930 (0.714-1.21) 1.14 (0.854-1.54) 1.32 (0.960-1.78) 1.50 (1.06-2.07) 1.69 (1.15-2.38) 1.96 (1.28-2.81) 2.17 (1.38-3.13) 15-min 0.634 (0.491-0.820) 0.752 (0.582-0.973) 0.956 (0.738-1.24) 1.14 (0.871-1.48) 1.40 (1.04-1.87) 1.61 (1.17-2.18) 1.83 (1.29-2.52) 2.06 (1.40-2.90) 2.39 (1.56-3.42) 2.65 (1.68-3.82) 30-min 0.892 (0.691-1.15) 1.06 (0.824-1.38) 1.36 (1.05-1.77) 1.62 (1.24-2.11) 2.00 (1.49-2.69) 2.31 (1.68-3.13) 2.63 (1.85-3.63) 2.97 (2.01-4.18) 3.45 (2.25-4.94) 3.83 (2.42-5.52) 60-min 1.16 (0.899-1.50) 1.38 (1.07-1.79) 1.78 (1.37-2.30) 2.14 (1.64-2.78) 2.69 (2.02-3.65) 3.16 (2.31-4.30) 3.66 (2.59-5.07) 4.21 (2.86-5.94) 4.99 (3.26-7.17) 5.62 (3.56-8.11) 2-hr 1.43 (1.12-1.83) 1.69 (1.33-2.17) 2.19 (1.71-2.81) 2.66 (2.06-3.42) 3.38 (2.58-4.56) 4.01 (2.97-5.42) 4.69 (3.36-6.46) 5.44 (3.74-7.63) 6.53 (4.32-9.33) 7.42 (4.75-10.6) 3-hr 1.59 (1.26-2.02) 1.88 (1.48-2.39) 2.43 (1.91-3.10) 2.97 (2.32-3.80) 3.83 (2.95-5.16) 4.58 (3.42-6.18) 5.41 (3.91-7.43) 6.34 (4.39-8.86) 7.69 (5.12-10.9) 8.80 (5.67-12.5) 6-hr 1.88 (1.50-2.35) 2.20 (1.75-2.77) 2.84 (2.26-3.58) 3.48 (2.75-4.39) 4.50 (3.52-6.02) 5.41 (4.10-7.25) 6.43 (4.70-8.75) 7.56 (5.30-10.5) 9.23 (6.22-13.0) 10.6 (6.92-15.0) 12-hr 2.13 (1.72-2.64) 2.52 (2.03-3.14) 3.26 (2.62-4.06) 3.96 (3.16-4.94) 5.04 (3.96-6.61) 5.97 (4.56-7.87) 6.99 (5.15-9.38) 8.12 (5.74-11.1) 9.74 (6.62-13.6) 11.1 (7.29-15.5) 24-hr 2.50 (2.04-3.06) 2.87 (2.34-3.52) 3.58 (2.91-4.40) 4.26 (3.45-5.26) 5.35 (4.26-6.96) 6.31 (4.87-8.23) 7.36 (5.49-9.79) 8.53 (6.11-11.6) 10.2 (7.05-14.2) 11.6 (7.76-16.1) 2-day 2.91 (2.40-3.53) 3.26 (2.69-3.96) 3.95 (3.25-4.81) 4.63 (3.78-5.65) 5.72 (4.61-7.35) 6.69 (5.23-8.64) 7.76 (5.86-10.2) 8.96 (6.49-12.0) 10.7 (7.46-14.7) 12.2 (8.20-16.7) 3-day 3.15 (2.62-3.80) 3.54 (2.94-4.27) 4.28 (3.54-5.17) 4.99 (4.11-6.05) 6.11 (4.94-7.77) 7.09 (5.58-9.08) 8.17 (6.21-10.7) 9.37 (6.83-12.5) 11.1 (7.78-15.1) 12.5 (8.51-17.1) 4-day 3.35 (2.80-4.01) 3.78 (3.15-4.53) 4.58 (3.81-5.50) 5.32 (4.40-6.42) 6.48 (5.25-8.17) 7.47 (5.90-9.50) 8.56 (6.52-11.1) 9.75 (7.13-12.9) 11.5 (8.06-15.5) 12.9 (8.76-17.5) 7-day 3.87 (3.27-4.60) 4.40 (3.71-5.22) 5.33 (4.47-6.34) 6.16 (5.14-7.36) 7.40 (6.03-9.18) 8.43 (6.69-10.6) 9.53 (7.31-12.2) 10.7 (7.88-14.0) 12.4 (8.76-16.6) 13.7 (9.42-18.5) 10-day 4.39 (3.72-5.17) 4.97 (4.22-5.86) 5.98 (5.05-7.07) 6.87 (5.77-8.15) 8.16 (6.67-10.0) 9.21 (7.34-11.4) 10.3 (7.95-13.1) 11.5 (8.49-14.9) 13.1 (9.32-17.5) 14.4 (9.95-19.4) 20-day 5.98 (5.14-6.97) 6.70 (5.75-7.80) 7.88 (6.74-9.21) 8.88 (7.55-10.4) 10.3 (8.46-12.4) 11.4 (9.15-13.9) 12.5 (9.70-15.6) 13.6 (10.2-17.4) 15.1 (10.9-19.9) 16.3 (11.4-21.7) 30-day 7.38 (6.39-8.53) 8.23 (7.12-9.52) 9.61 (8.28-11.1) 10.7 (9.20-12.5) 12.3 (10.1-14.6) 13.4 (10.9-16.2) 14.6 (11.4-18.0) 15.7 (11.8-19.9) 17.2 (12.4-22.4) 18.3 (12.9-24.2) 45-day 9.18 (8.00-10.5) 10.3 (8.94-11.8) 12.0 (10.4-13.8) 13.3 (11.5-15.4) 15.1 (12.5-17.8) 16.4 (13.3-19.6) 17.6 (13.8-21.6) 18.8 (14.2-23.6) 20.2 (14.7-26.1) 21.2 (15.1-28.0) 60-day 10.7 (9.40-12.2) 12.1 (10.6-13.8) 14.1 (12.3-16.1) 15.7 (13.6-18.0) 17.7 (14.8-20.7) 19.2 (15.6-22.8) 20.5 (16.2-24.9) 21.7 (16.5-27.1) 23.2 (16.9-29.8) 24.2 (17.2-31.8) 1 Precipitation frequency (PF) estimates in this table are based on frequency analysis of partial duration series (PDS). Numbers in parenthesis are PF estimates at lower and upper bounds of the 90% confidence interval. The probability that precipitation frequency estimates (for a given duration and average recurrence interval) will be greater than the upper bound (or less than the lower bound) is 5%. Estimates at upper bounds are not checked against probable maximum precipitation (PMP) estimates and may be higher than currently valid PMP values. Please refer to NOAA Atlas 14 document for more information. Back to Top PF graphical Page 1 of 3Precipitation Frequency Data Server 6/3/2015http://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?lat=44.8849&lon=-93.5599&data=... Back to Top Maps & aerials Small scale terrain Large scale terrain Map data © 2015 GoogleReport a map error50 km Page 2 of 3Precipitation Frequency Data Server 6/3/2015http://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?lat=44.8849&lon=-93.5599&data=... Large scale aerial Back to Top US Department of Commerce National Oceanic and Atmospheric Administration National Weather Service Office of Hydrologic Development 1325 East West Highway Silver Spring, MD 20910 Questions?: HDSC.Questions@noaa.gov Disclaimer Map data © 2015 GoogleReport a map error2 km Imagery © 2015 TerraM etricsReport a map error2 km Page 3 of 3Precipitation Frequency Data Server 6/3/2015http://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?lat=44.8849&lon=-93.5599&data=... LA K E LU C Y RO A D SU B D I V I S I O N La n d Co v e r an d Vo l u m e Ma n a g e m e n t Re q u i r e m e n t Ca l c u l a t i o n Ty p e "C " So i l s As s u m e d Ex i s t i n g Co n d i t i o n s Dr a i n a g e Ar e a [f t 2 ] [a c r e ] [f t 2 ] [a c r e ] [f t 2 ] [a c r e ] [f t 2 ] [a c r e ] [f t 2 ] [a c r e ] [ft 2 ][acre] LW 2 4 7 7 6 0 . 5 6 9 2 9 7 9 0 . 0 6 8 1 7 5 6 0 . 0 4 0 4 9 4 7 0 . 1 1 4 1 5 0 9 4 0 . 3 4 7 0 0 . 0 0 0 W ‐1 1 1 2 8 7 0 2 . 5 9 1 1 3 7 0 9 0 . 3 1 5 0 0 . 0 0 0 7 0 0 3 5 1 . 6 0 8 9 5 4 8 0 . 2 1 9 1 9 5 7 8 0 . 4 4 9 3. 1 6 0 16 6 8 8 Of f s i t e W ‐1( O ) 3 9 7 0 5 0 9 . 1 1 5 3 7 5 4 9 0 . 8 6 2 3 8 7 7 0 . 0 8 9 1 6 2 5 6 6 3 . 7 3 2 1 2 0 6 6 1 2 . 7 7 0 7 2 3 9 7 1 . 6 6 2 12 . 2 7 5 Pr o p o s e d Co n d i t i o n s Dr a i n a g e Ar e a [f t 2 ] [a c r e ] [f t 2 ] [a c r e ] [f t 2 ] [a c r e ] [f t 2 ] [a c r e ] [f t 2 ] [a c r e ] [ft 2 ][acre] P ‐1 96 3 4 9 2 . 2 1 2 2 2 4 0 1 0 . 5 1 4 0 0 . 0 0 0 2 3 4 7 9 0 . 5 3 9 3 0 8 9 6 0 . 7 0 9 1 9 5 5 8 0 . 4 4 9 P ‐2 41 2 9 8 0 . 9 4 8 1 9 7 7 6 0 . 4 5 4 0 0 . 0 0 0 1 1 4 0 1 0 . 2 6 2 1 0 1 2 1 0 . 2 3 2 0 0 . 0 0 0 3. 1 6 0 42 1 7 7 Of f s i t e W ‐1( O ) 3 9 7 0 5 0 9 . 1 1 5 3 7 5 4 9 0 . 8 6 2 3 8 7 7 0 . 0 8 9 1 6 2 5 6 6 3 . 7 3 2 1 2 0 6 6 1 2 . 7 7 0 7 2 3 9 7 1 . 6 6 2 12 . 2 7 5 13 2 6 8 S F O r 0. 3 0 A C I" in f i l t r a t i o n vo l u m e re q u i r e d = 1 1 0 6 C F Or 0. 0 2 5 A F Pr o p o s e d Fi l t r a t i o n Ba s i n Vo l u m e Pr o v i d e d Ba s i n T o t a l Vo l u m e Re t e n t i o n Pi p e In v e r t Pi p e Ov e r f l o w [f t 3 ] El e v E l e v WL 1 1 3 1 1 0 1 6 . 0 0 0 1 0 2 0 . 0 0 0 CN=98 Water CN=98 Water To t a l in c r e a s e d on s i t e im p e r v i o u s su r f a c e = Gr a v e l w/ o RW Im p e r v i o u s CN = 9 8 To t a l Ar e a Fr i d a y , Ma y 22 , 20 1 5 CN = 7 4 Pe r v i o u s (G r a s s ) CN = 7 4 Pe r v i o u s (G r a s s ) Gr a v e l w/ o RW CN = 9 6 C N = 7 0 CN = 9 8 Im p e r v i o u s CN = 7 0 Wo o d s Wo o d s To t a l Ar e a CN = 9 6 ST O R M S E W E R D E S I G N W O R K S H E E T - P O S T - D E V E L O P M E N T C O N D I T I O N S ALLIANT ENGINEERING, INC. PR O J E C T N A M E : G L A C C U M P R O P E R T Y 233 PARK AVENUE SOUTH PR O J E C T N U M B E R : 1 5 0 0 3 0 SUITE 300 PR E P A R E D B Y : P L N MINNEAPOLIS, MN 55415 Rim=CL-0.605 4' MIN BUILD DE S I G N S T O R M F R E Q U E N C Y = 1 0 Y E A R S IM P R U N O F F I N T E N S I T Y P . D I A . P . S L O P E P. M a t MA N N I N G ' S P . C A P . P . V E L O C I T Y P I P E C A P . O V E R F R O M T O R I M C o v e r S T R . C A S T B U I L D P i p e FR O M T O T O T A L I M P E R V I O U S I N C R . C U M . % C I N C R . C U M . P I P E C U M . i I N C R . C U M . D [ I N ] S [ F T / F T ] n Q [ C F S ] M A X [ F T / S ] L E N G T H [ F T ] Q [ C F S ] I N V E R T I N V E R T E L E V [ FT] T Y P E T Y P E [ F T ] C l a s s CB 1 0 0 O S C 1 0 1 36 8 7 8 19 7 7 6 0. 8 4 7 0 . 8 4 7 5 4 % 0 . 5 8 0 . 4 8 7 0 . 4 8 7 15 . 0 0 15 . 0 0 4 . 7 7 2 . 3 2 3 2 . 3 2 3 48 0 . 0 0 2 7 HD P E 0. 0 1 1 8 7 . 6 6 6 . 9 8 75.0 85.3406 1016.00 1015.80 1027.50 7.30 7 2 R-3067-V 11.50 OS C 1 0 1 M H 1 0 2 00 0. 0 0 0 0 . 8 4 7 0 % 0 . 2 0 0 . 0 0 0 0 . 0 0 0 1 5 . 0 0 1 5 . 0 0 4 . 7 7 0 . 0 0 0 0 . 0 0 0 12 0 . 3 0 0 0 RC P 0. 0 1 3 1 9 . 5 1 2 4 . 8 5 57.0 19.5143 1020.00 1002.90 1024.50 3.30 7 2 R-1642 4.50 5 MH 1 0 2 F E S 1 0 3 00 0. 0 0 0 1 . 6 9 3 0 % 0 . 2 0 0 . 0 0 0 0 . 4 8 7 0 . 0 0 1 5 . 0 0 4 . 7 7 0 . 0 0 0 2 . 3 2 3 12 0 . 0 1 0 0 RC P 0. 0 1 3 3 . 5 6 4 . 5 4 43.0 1.2396 1 0 0 2 . 4 0 1 0 0 1 . 9 7 1012.00 8.40 4 8 R-4342 9.60 5 Q [ C F S ] MH / C B A R E A [ A C ] T I M E O F C O N C . [ M I N ] AR E A [ S F ] A * C