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Lake Minnewashta Permit Application 072214_reduced[1] engineering planning environmental construction 701 Xenia Avenue South Suite 300 Minneapolis, MN 55416 Tel: 763-541-4800 Fax: 763-541-1700 Equal Opportunity Employer wsbeng.com K:\01945-050\Admin\Permits\MEMO - 072214 - Agency application.docx Memorandum To: Courtney Hall, Minnehaha Creek Watershed District Melissa Jenny, US Corps of Engineers Ben Meyer, BWSR Jennie Skancke, DNR Brooke Haworth, DNR Mike Wanous, Carver SWCD Terry Jeffery, City of Chanhassen Copy: Marty Walsh, Carver County Morgan Dawley, WSB & Associates From: Andi Moffatt, WSB & Associates Date: July 22, 2014 Re: Carver County Lake Minnewashta Regional Park Improvements Permit Application WSB Project No. 1945-050 On behalf of Carver County, attached, please find a permit application and supporting documents for the Lake Minnewashta Regional Park Improvement Project. This application is for wetland impacts and watershed district approval. Project Description: Carver County Parks has received grant funding for proposed improvements to Lake Minnewashta Regional Park that incudes; road reshaping/paving (5657 linear feet), an access road to the dog park (1587 linear feet), boat launch improvements, some trail improvements (500 linear feet realigned), and construction of an entrance turnaround. The purpose of this project is to improve the public amenities within the park as well as provide safer access along the road for the public. The project is within the Minnehaha Creek Watershed District (MCWD). The Riley-Purgatory Bluff Creek Watershed District (RPBCWD) has indicated the project is not within their boundaries. In total, the project will disturb 10.37 acres of land. The existing impervious surface is 6.04 acres and the proposed impervious is 6.49 acres for a net increase of 0.45 acres. This includes 500 linear feet of trail improvements, the reconstructed boat launch, reconstructed parking area for the boat launch, and entrance turnaround area. With the trail, new bituminous trail is being constructed as well as demarcation of a cross-country skiing trail. The road within the park will be resurfaced from gravel to bituminous and a bypass lane at the park entrance will be constructed. July 22, 2014 Page 2 K:\01945-050\Admin\Permits\MEMO - 072214 - Agency application.docx A previous delineation was completed in the Lake Minnewashta Regional Park by SRF Consulting Group and LGU approved in 2011. The 2011 wetland boundaries are shown on the project plans. Additional wetland was delineated by WSB in September 2013. A complete delineation report was submitted to the City of Chanhassen as the LGU for WCA on February 21, 2014. Attached with this application are the following appendices: Appendix A – Figures Appendix B – Plan set Appendix C – NPDES Permit Appendix D – Supporting Stormwater Management Analysis A discussion of how the project meets the MCWD rules is provided below. Wetlands and Buffers Wetlands have been avoided to the extent practical and the project anticipates 2191 sf (0.05 acres) of wetland impact. About 0.383 sf (0.009 acres) of trail will also be removed from a wetland. The attached wetland application addresses wetland sequencing. Wetland impacts are proposed to be mitigated by purchase of wetland credits, anticipated through the purchase of 0.1 acres from the Jeff Richards bank # 1375 in Carver County. The purchase agreement will be submitted under separate cover. The MCWD requires wetland buffers for projects that trigger the wetland or stormwater rule, as this project does. A buffer on public land, as is the case with this project, can be documented by written agreement with the District and the County. This is the County’s preferred route. The buffer width is based on the District’s wetland assessment. Based on this assessment, the wetlands have the following classifications and resulting buffer widths and are shown on the attached plans in Appendix A. Wetland (SRF delineation label in parentheses) Wetland Type (at project area) Management Classification (based on MCWD assessment) Watershed District Required Buffer Width (max/min) in feet Provided Buffer Width in feet A 3 Manage 2 MCWD 30 / 16 3-30 D 3 Preserve MCWD 75 / 67 0 E (W9) 6 Manage 1 MCWD MCWD – 40 / 34 10-40 F (W21) 6 Preserve MCWD 75 / 67 3-75 H (W22) 2 Manage 3 MCWD 20 / 16 0-20 Erosion Control Plans The construction plans attached include erosion control and turf establishment plans as Sheet 20-23. The SWPPP is in Sheets 24-27. These plans meet the requirements of the erosion control rule. The plans include biorolls, silt fence, rock check entrance, and seeding. Receiving July 22, 2014 Page 3 K:\01945-050\Admin\Permits\MEMO - 072214 - Agency application.docx waters include surrounding small wetlands and ultimately Lake Minnewashta. A copy of the NPDES permit is also attached. Stormwater Management As stated, this project involves paving approximately 1-mile of the existing gravel entrance road from Hazeltine Boulevard into Lake Minnewashta Regional Park. Additionally, the existing gravel boat launch parking lots (Appendix D) will be removed. The southerly lot will be replaced with an expanded parking lot and new boat launch (see plan set in Appendix B). Existing conditions land use is park land. Drainage patterns will not change from existing. • The total project area is 10.37 acres • Existing impervious surfaces in MCWD (including gravel) = 6.04 acres • Proposed impervious surfaces in MCWD = 6.49 acres • Increase in impervious surfaces in MCWD = 0.45 acres Based MCWD Stormwater Management Rule Table 5 the project is required to provide phosphorus control and rate control for the net increase in impervious surfaces. The increase in impervious is entirely due to the proposed boat launch parking lot; therefore BMPs have been focused in this location. Rate Control: MCWD requires that applicants demonstrate that their discharge rates have not increased from the pre-development for the 1-year, 10-year, and 100-year critical storm events. There is no increase in impervious surfaces for the proposed entrance road and therefore no change in discharge rate. The existing culverts are proposed to be replaced in-kind. The existing and proposed discharge rates to Lake Minnewashta from the proposed boat launch parking lot are listed in Table 1. Table 1: Discharge Rate Comparison 2-Year (CFS) 10-Year (CFS) 100- Year* (CFS) Existing 1.0 4.9 12.6 Proposed 1.9 6.8 7.4 *Includes overflow over Brockton Road. The proposed discharge rates are less than or equal to existing for all storm events. See attached HydroCAD output for detailed results in Appendix D. Water Quality: MCWD requires phosphorus loadings for post-development to be less than or equal to existing phosphorus levels. P8 modeling was used to evaluate the water quality treatment of the proposed BMPs. Pre-development TP load = 9.5 lb/yr Post-development TP load = 0.5 lb/yr July 22, 2014 Page 4 K:\01945-050\Admin\Permits\MEMO - 072214 - Agency application.docx A series of infiltration basins and a pond are proposed within the boat launch parking lot to provide water quality treatment. Supporting Documentation: The documents provided with this memo for review are: • Drainage Maps – Appendix D • HydroCAD Results – Appendix D • P8 results – Appendix D • Plan Set – Appendix B Floodplain FEMA floodplain elevation is 945.0. The OHW is 944.5. The existing boat launch will be reconstructed to accommodate better public access in this area. Currently, the boat launch has limited capacity and one launch area. The proposed launch will be reconstructed in the current location and include a double launch. The boat launch will be constructed to meet the DNR’s Boat Ramp guidelines and as such, does not require a permit from the DNR. The design includes a double launch with concrete planks. The launch will extend from the upland side at elevation 946.3 into the water to elevation 943.93 as shown on the plans. The boat launch will result in 35 cy of fill in the floodplain. Based on the size of the basin, this will not increase the floodplain elevation of the lake. Project Timing: The project is anticipated to start September 1, 2014 and be completed October 31, 2015. Permit Request: On behalf of the City, we are requesting a permit from the MCWD, approval from the LGU for the WCA, and approval from the COE under Section 404. If you have any questions or need additional information, please feel free to call me at 763-287-7196. Minnesota Interagency Water Resource Application Form February 2014 Page 10 of 13 Project Name and/or Number: Attachment D Replacement/Compensatory Mitigation Complete this part if your application involves wetland replacement/compensatory mitigation not associated with the local road wetland replacement program. Applicants should consult Corps mitigation guidelines and WCA rules for requirements. Replacement/Compensatory Mitigation via Wetland Banking. Complete this section if you are proposing to use credits from an existing wetland bank (with an account number in the State wetland banking system) for all or part of your replacement/compensatory mitigation requirements. Wetland Bank Account # County Major Watershed # Bank Service Area # Credit Type (if applicable) Number of Credits 1375 Carver 19 7 SWC 0.10 Applicants should attach documentation indicating that they have contacted the wetland bank account owner and reached at least a tentative agreement to utilize the identified credits for the project. This documentation could be a signed purchase agreement, signed application for withdrawal of credits or some other correspondence indicating an agreement between the applicant and the bank owner. However, applicants are advised not to enter into a binding agreement to purchase credits until the mitigation plan is approved by the Corps and LGU. Project-Specific Replacement/Permittee Responsible Mitigation. Complete this section if you are proposing to pursue actions (restoration, creation, preservation, etc.) to generate wetland replacement/compensatory mitigation credits for this proposed project. WCA Action Eligible for Credit1 Corps Mitigation Compensation Technique2 Acres Credit % Requested Credits Anticipated3 County Major Watershed # Bank Service Area # 1Refer to the name and subpart number in MN Rule 8420.0526. 2Refer to the technique listed in St. Paul District Policy for Wetland Compensatory Mitigation in Minnesota. 3If WCA and Corps crediting differs, then enter both numbers and distinguish which is Corps and which is WCA. Explain how each proposed action or technique will be completed (e.g. wetland hydrology will be restored by breaking the tile……) and how the proposal meets the crediting criteria associated with it. Applicants should refer to the Corps mitigation policy language, WCA rule language, and all associated Corps and WCA guidance related to the action or technique: Attach a site location map, soils map, recent aerial photograph, and any other maps to show the location and other relevant features of each wetland replacement/mitigation site. Discuss in detail existing vegetation, existing landscape features, land use (on and surrounding the site), existing soils, drainage systems (if present), and water sources and movement. Include a topographic map showing key features related to hydrology and water flow (inlets, outlets, ditches, pumps, etc.): Appendix A – Figures Che s M a r D r . Minnewashta Reg i o n a l P a r k R d . Chanhassen Shorewood Excelsior Chaska Tonka Bay Victoria Sources: Esri, DeLorme, NAVTEQ, USGS, Intermap, iPC, NRCAN, Esri Japan, METI, Esri China (Hong Kong), Esri (Thailand), TomTom, 2013 ¹1 inch = 2,000 feet Figure 1. Project LocationLake Minnewashta Regional ParkChanhassen, Minnesota Do c u m e n t P a t h : K : \ 0 1 9 4 5 - 0 5 0 \ G I S \ M a p s \ 0 1 9 4 5 - 0 5 0 _ F i g 1 _ p r o j _ l o c . m x d Legend Project Limits Lake Minnewashta City Limits Che s M a r D r . Minnewashta Reg i o n a l P a r k R d . Chanhassen Shorewood Excelsior Chaska Tonka Bay Victoria Copyright:© 2011 National Geographic Society, i-cubed¹1 inch = 2,000 feet Figure 1a. USGS MapLake Minnewashta Regional ParkChanhassen, Minnesota Do c u m e n t P a t h : K : \ 0 1 9 4 5 - 0 5 0 \ G I S \ M a p s \ 0 1 9 4 5 - 0 5 0 _ F i g 1 a _ u s g s . m x d Legend Project Limits Lake Minnewashta City Limits Che s M a r D r . Minnewashta Regional Park Rd. Haz e l t i n e B l v d . ( S t a e t H i g h w a y 4 1 ) L2ABH PEM1F L2UBHPEM1F PEM1C L2UBH L1UBH PUBG PUBGx PUBG PEM1C PEM1C PABG PEM1C PFO1A PEM1C PEM1A PEM1A PEM1A PEM1F PSS1C PEM1A PEM1C PEM1F PABG PFO1A PUBGx PEM1C PUBGPUBF PUBF L2ABH PEM1A PUBGx PEM1C PEM1A PEM1C PEM1C 10000900 10000900 10000900 27013200 ¹1 inch = 500 feet Figure 2. National Wetlands Inventory & DNR Public Waters InventoryLake Minnewashta Regional ParkChanhassen, Minnesota Legend National Wetlands Inventory DNR Public Waters Inventory Project Limits Do c u m e n t P a t h : K : \ 0 1 9 4 5 - 0 5 0 \ G I S \ M a p s \ 0 1 9 4 5 - 0 5 0 _ F i g 2 _ n w i - p w i . m x d Lake Minnewashta Che s M a r D r . Minnewashta Regional Park Rd. Haz e l t i n e B l v d . ( S t a e t H i g h w a y 4 1 ) KC LAKE PM KE2 KD KC2 KC HM KE2 KE2 KD KC EX TB HM MP HM KC2 KB ND3 TB KC HM MK MK KE2 EX NE3EX EX MP KD KB KC2 KE2 KD KC KB2 MK KD2 MP KC KD2 KB EX KB KE2 KC KD2 HM KB KC KE2 KD2 KD TC HM HM GL KB KD2 GL MP KD2 KD KD2 KC2 KB KCTB ND3 HM TB KC2 TB KB2 KC KD2 KD2 HM HM MP NE3 KB2 NE3ND3 KB KB2 LA KC2 KE2 KB GL KD2 ¹1 inch = 500 feet Figure 3. Carver County Soil SurveyLake Minnewashta Regional ParkChanhassen, Minnesota Legend Carver County Soil Survey Non-Hydric Hydric Project Limits Do c u m e n t P a t h : K : \ 0 1 9 4 5 - 0 5 0 \ G I S \ M a p s \ 0 1 9 4 5 - 0 5 0 _ F i g 3 _ s o i l s . m x d MUSYMMUNAME EXEssexville sandy loam GLGlencoe clay loam HMHamel loam KBKilkenny-Lester loams, 2 to 6 percent slopes KB2lester-kilkenny loams, 2 to 6 percent slopes, eroded KCLester-Kilkenny loams, 6 to 12 percent slopes KC2lester-kilkenny loams, 6 to 12 percent slopes, eroded KDLester-Kilkenny loams, 12 to 18 percent slopes KD2lester-kilkenny loams, 12 to 18 percent slopes, eroded KE2Lester-Kilkenny loams, 18 to 25 percent slopes, eroded LALe Sueur-Lester loams, 1 to 4 percent slopes LAKE MKHoughton and Muskego soils MPKlossner and Muskego soils, ponded ND3Lester-Kilkenny clay loams, 12 to 18 percent slopes, se verely eroded NE3Lester-Kilkenny clay loams, 18 to 25 percent slopes, se verely eroded PMKlossner muck TBTerril loam, 0 to 6 percent slopes TCTerril loam, 6 to 12 percent slopes Che s M a r D r . Minnewashta Regional Park Rd. Haz e l t i n e B l v d . ( S t a e t H i g h w a y 4 1 ) ¹1 inch = 512 feet Figure 4. Wetland Locations & Review AreasLake Minnewashta Regional ParkChanhassen, Minnesota Legend Wetland A Wetland B Wetland C Wetland D Area 1* Area 2* Area 3* Area 4* Project Limits Do c u m e n t P a t h : K : \ 0 1 9 4 5 - 0 5 0 \ G I S \ M a p s \ 0 1 9 4 5 - 0 5 0 _ F i g 4 _ w e t _ l o c . m x d *Preliminary project areas identified for wetland delineation field review that do not meet the 30 MPH curve radius per State Aid Design Standards. ! !!!!! ! !! !!! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! !!!! ! ! !!! !! ! ! ! ! !! ! ! ! ! !! !! ! ! ! !!! ! ! !! ! !!! !! ! ! ! ! ! ! ! !!!!!!!!!! !! AREA J AREA F M-588 M-5 9 0 Ch e s M a r F a r m R d M-59 2 Hig h o v e r D r M-5 9 1 ?A41 w2-t1-upw2-1-start w2-3w2-3 w2-6 w2-7w2-8 w2-9w2-10 w2-11 w2-12-end ditch start ditch middle w3-t1-wet w3-1-start w3-2 w3-14 w3-15 w3-16 w3-17-end Area A Area B w8-1 start w8-2 w8-3 w8-4 w8-5 w8-6 w8-7 w8-8 w8-9end ditch start ditch end ditch w9-1-start w9-2w9-3w9-4 w9-5 w9-6-3nd w10-t1-up w10-1-start w10-3w10-2 w10-4 w11-t1-wet w11-t1-upw11-2w11-4 w11-5 w12-2 w12-2 w12-4 w12-5 w12-6 w12-7 end w13-1-start w13-2 w13-4 w13-5 w13-7 w13-8 w12-10-end w22-1startw22-3 w22-4 w22-6 w22-8 w22-9 w22-10 w22-11 w22-12end Figure 2B J: \ M a p s \ 7 0 6 8 \ m x d \ 7 0 6 8 _ w e t l a n d s _ f i g u r e 2 b . m x d Delineated Wetland Boundary Carver County TH41 Underpass and Trail Project Carver County, Minnesota 0 300150Feet ± !GPS Survey Points Construction Limits Delineated Wetland Boundaries Wet Ditch Hydric Soils National Wetland Inventory 2014 PARK IMPROVEMENT PROJECT CARVER COUNTY, MINNESOTA LAKE MINNEWASHTA REGIONAL PARK WETLAND A WE T L A N D E (T Y P E 4 ) (TYPE 3) 2014 PARK IMPROVEMENT PROJECT CARVER COUNTY, MINNESOTA LAKE MINNEWASHTA REGIONAL PARK WETLAND F(TYPE F) 2014 PARK IMPROVEMENT PROJECT CARVER COUNTY, MINNESOTA LAKE MINNEWASHTA REGIONAL PARK WE T L A N D G WETLAND D WE T L A N D E WETLAND H(TYPE 2)(TYPE 3) (T Y P E 2 ) (T Y P E 4 ) LAKE MINNEWASHTA 2014 PARK IMPROVEMENT PROJECT CARVER COUNTY, MINNESOTA LAKE MINNEWASHTA REGIONAL PARK WETLAND A WE T L A N D E (T Y P E 4 ) (TYPE 3) 4 0 ' W E T L A N D B U F F E R (M C W D ) PROVIDED BUFFER PR O V I D E D B U F F E R 30' WETLAND BUFFER(MCWD) 2014 PARK IMPROVEMENT PROJECT CARVER COUNTY, MINNESOTA LAKE MINNEWASHTA REGIONAL PARK WETLAND F(TYPE F)(MCWD) 75' WETLAND BUFFERPROVIDED BUFFER 2014 PARK IMPROVEMENT PROJECT CARVER COUNTY, MINNESOTA LAKE MINNEWASHTA REGIONAL PARK LAKE MINNEWASHTA (M C W D ) 4 0 ' W E T L A N D B U F F E R (T Y P E 4 ) WE T L A N D E (T Y P E 2 ) WE T L A N D G (M C W D ) 7 5 ' W E T L A N D B U F F E R (TYPE 3)WETLAND D(MCWD) 20' WETLAND BUFFERWETLAND H(TYPE 2) PR O V I D E D B U F F E R PROVIDED BUFFER Appendix B – Plan set Appendix C – NPDES Permit Permit Coverage Date: 7/17/2014 Permit ID Number:C00038580 Owner:Carver County General Contractor:Carver County Project Name:Lake Minnewashta Regional Park Improveme CSW If you have questions regarding the stormwater program for construction activity, please access the MPCA Stormwater website at http:www.pca.state.mn.us/stormwater, or call the Construction Stormwater Program at 651-757-2119 or toll free at 800-657-3804. Construction Stormwater National Pollutant Discharge Elimination System/State Disposal System General Permit MNR100001 The Construction site identified below is covered under the National Pollutant Discharge Elimination System/State Disposal System General Permit MNR100001 and is authorized by the Minnesota Pollution Control Agency (MPCA) to discharge stormwater associated with construction activities. Coverage Card Appendix D – Supporting Stormwater Management Analysis LakeMinnewashta Park Entr a n c e D r i v e LakeMinnewashtaRegional Park 2014 PARK IMPROVEMENT PROJECT CARVER COUNTY, MINNESOTA LAKE MINNEWASHTA REGIONAL PARK BE N C H M A R K E L E V BE N C H M A R K E L E V 3S 5S 6S 8S 9S Existing Boat Launch 10S north boat launch - gravel removed 8R swale 10R to Minnewashta PROPOSED 1P Rain Garden 2P Rain Garden w/ Yard Drain 4P Stormwater Basin 7P Routing Diagram for Boat Landing Prepared by HP, Printed 7/7/2014 HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Subcat Reach Pond Link Boat Landing Printed 7/7/2014Prepared by HP Page 2HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Area Listing (all nodes) Area (acres) CNDescription (subcatchment-numbers) 1.27698 (3S, 5S, 6S, 8S) 1.42161 (3S, 5S, 6S, 10S) 1.29761>75% Grass cover, Good, HSG B (9S) 0.80085existing north parking lot (9S) 0.60085existing south parking lot (9S) 5.39476TOTAL AREA Type II 24-hr 1yr Rainfall=2.40"Boat Landing Printed 7/7/2014Prepared by HP Page 3HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=0.396 ac 94.44% Impervious Runoff Depth>1.84"Subcatchment 3S: Tc=10.0 min CN=96 Runoff=1.10 cfs 0.061 af Runoff Area=1.030 ac 69.90% Impervious Runoff Depth>1.13"Subcatchment 5S: Tc=10.0 min CN=87 Runoff=1.92 cfs 0.097 af Runoff Area=0.309 ac 6.47% Impervious Runoff Depth>0.18"Subcatchment 6S: Tc=10.0 min CN=63 Runoff=0.05 cfs 0.005 af Runoff Area=0.162 ac 100.00% Impervious Runoff Depth>2.02"Subcatchment 8S: Tc=10.0 min CN=98 Runoff=0.47 cfs 0.027 af Runoff Area=2.697 ac 0.00% Impervious Runoff Depth>0.45"Subcatchment 9S: Existing Boat Launch Tc=10.0 min CN=73 Runoff=1.88 cfs 0.102 af Runoff Area=0.800 ac 0.00% Impervious Runoff Depth>0.14"Subcatchment 10S: north boat launch - Tc=10.0 min CN=61 Runoff=0.07 cfs 0.009 af Avg. Flow Depth=0.07' Max Vel=2.05 fps Inflow=0.49 cfs 0.024 afReach 8R: swale n=0.030 L=230.0' S=0.0674 '/' Capacity=306.66 cfs Outflow=0.42 cfs 0.024 af Inflow=1.03 cfs 0.119 afReach 10R: to Minnewashta PROPOSED Outflow=1.03 cfs 0.119 af Peak Elev=965.11' Storage=0.033 af Inflow=1.10 cfs 0.061 afPond 1P: Rain Garden Discarded=0.01 cfs 0.006 af Primary=0.49 cfs 0.024 af Outflow=0.50 cfs 0.030 af Peak Elev=949.69' Storage=0.014 af Inflow=1.92 cfs 0.121 afPond 2P: Rain Garden w/ Yard Drain Discarded=0.00 cfs 0.003 af Primary=1.89 cfs 0.106 af Secondary=0.00 cfs 0.000 af Outflow=1.90 cfs 0.109 af Peak Elev=946.51' Storage=0.060 af Inflow=1.94 cfs 0.110 afPond 4P: Stormwater Basin Primary=0.98 cfs 0.106 af Secondary=0.00 cfs 0.000 af Outflow=0.98 cfs 0.106 af Peak Elev=952.51' Storage=0.017 af Inflow=0.47 cfs 0.027 afPond 7P: Discarded=0.01 cfs 0.006 af Primary=0.05 cfs 0.004 af Outflow=0.06 cfs 0.010 af Total Runoff Area = 5.394 ac Runoff Volume = 0.300 af Average Runoff Depth = 0.67" 76.34% Pervious = 4.118 ac 23.66% Impervious = 1.276 ac Type II 24-hr 1yr Rainfall=2.40"Boat Landing Printed 7/7/2014Prepared by HP Page 4HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment 3S: Runoff=1.10 cfs @ 12.01 hrs, Volume=0.061 af, Depth>1.84" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 1yr Rainfall=2.40" Area (ac)CNDescription *0.37498 *0.02261 0.39696Weighted Average 0.0225.56% Pervious Area 0.37494.44% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Subcatchment 3S: Runoff Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 1 0 Type II 24-hr 1yr Rainfall=2.40" Runoff Area=0.396 ac Runoff Volume=0.061 af Runoff Depth>1.84" Tc=10.0 min CN=96 1.10 cfs Type II 24-hr 1yr Rainfall=2.40"Boat Landing Printed 7/7/2014Prepared by HP Page 5HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment 5S: Runoff=1.92 cfs @ 12.02 hrs, Volume=0.097 af, Depth>1.13" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 1yr Rainfall=2.40" Area (ac)CNDescription *0.72098 *0.31061 1.03087Weighted Average 0.31030.10% Pervious Area 0.72069.90% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Subcatchment 5S: Runoff Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 2 1 0 Type II 24-hr 1yr Rainfall=2.40" Runoff Area=1.030 ac Runoff Volume=0.097 af Runoff Depth>1.13" Tc=10.0 min CN=87 1.92 cfs Type II 24-hr 1yr Rainfall=2.40"Boat Landing Printed 7/7/2014Prepared by HP Page 6HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment 6S: Runoff=0.05 cfs @ 12.07 hrs, Volume=0.005 af, Depth>0.18" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 1yr Rainfall=2.40" Area (ac)CNDescription *0.02098 *0.28961 0.30963Weighted Average 0.28993.53% Pervious Area 0.0206.47% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Subcatchment 6S: Runoff Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 0.055 0.05 0.045 0.04 0.035 0.03 0.025 0.02 0.015 0.01 0.005 0 Type II 24-hr 1yr Rainfall=2.40" Runoff Area=0.309 ac Runoff Volume=0.005 af Runoff Depth>0.18" Tc=10.0 min CN=63 0.05 cfs Type II 24-hr 1yr Rainfall=2.40"Boat Landing Printed 7/7/2014Prepared by HP Page 7HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment 8S: Runoff=0.47 cfs @ 12.01 hrs, Volume=0.027 af, Depth>2.02" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 1yr Rainfall=2.40" Area (ac)CNDescription *0.16298 0.162100.00% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Subcatchment 8S: Runoff Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 0.52 0.5 0.48 0.46 0.44 0.42 0.4 0.38 0.36 0.34 0.32 0.3 0.28 0.26 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 Type II 24-hr 1yr Rainfall=2.40" Runoff Area=0.162 ac Runoff Volume=0.027 af Runoff Depth>2.02" Tc=10.0 min CN=98 0.47 cfs Type II 24-hr 1yr Rainfall=2.40"Boat Landing Printed 7/7/2014Prepared by HP Page 8HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment 9S: Existing Boat Launch Runoff=1.88 cfs @ 12.04 hrs, Volume=0.102 af, Depth>0.45" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 1yr Rainfall=2.40" Area (ac)CNDescription *0.60085existing south parking lot 1.29761>75% Grass cover, Good, HSG B *0.80085existing north parking lot 2.69773Weighted Average 2.697100.00% Pervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Subcatchment 9S: Existing Boat Launch Runoff Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 2 1 0 Type II 24-hr 1yr Rainfall=2.40" Runoff Area=2.697 ac Runoff Volume=0.102 af Runoff Depth>0.45" Tc=10.0 min CN=73 1.88 cfs Type II 24-hr 1yr Rainfall=2.40"Boat Landing Printed 7/7/2014Prepared by HP Page 9HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment 10S: north boat launch - gravel removed Runoff=0.07 cfs @ 12.08 hrs, Volume=0.009 af, Depth>0.14" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 1yr Rainfall=2.40" Area (ac)CNDescription *0.80061 0.800100.00% Pervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Subcatchment 10S: north boat launch - gravel removed Runoff Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 0.075 0.07 0.065 0.06 0.055 0.05 0.045 0.04 0.035 0.03 0.025 0.02 0.015 0.01 0.005 0 Type II 24-hr 1yr Rainfall=2.40" Runoff Area=0.800 ac Runoff Volume=0.009 af Runoff Depth>0.14" Tc=10.0 min CN=61 0.07 cfs Type II 24-hr 1yr Rainfall=2.40"Boat Landing Printed 7/7/2014Prepared by HP Page 10HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Reach 8R: swale Inflow Area =0.396 ac,94.44% Impervious, Inflow Depth > 0.72" for 1yr event Inflow=0.49 cfs @ 12.16 hrs, Volume=0.024 af Outflow=0.42 cfs @ 12.23 hrs, Volume=0.024 af, Atten= 15%, Lag= 4.3 min Routing by Stor-Ind+Trans method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Max. Velocity= 2.05 fps, Min. Travel Time= 1.9 min Avg. Velocity = 0.98 fps, Avg. Travel Time= 3.9 min Peak Storage= 51 cf @ 12.20 hrs Average Depth at Peak Storage= 0.07' Bank-Full Depth= 2.00' Flow Area= 22.0 sf, Capacity= 306.66 cfs 3.00' x 2.00' deep channel, n= 0.030 Side Slope Z-value= 4.0 '/' Top Width= 19.00' Length= 230.0' Slope= 0.0674 '/' Inlet Invert= 965.50', Outlet Invert= 950.00' ‡ Reach 8R: swale Inflow Outflow Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 0.55 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Inflow Area=0.396 ac Avg. Flow Depth=0.07' Max Vel=2.05 fps n=0.030 L=230.0' S=0.0674 '/' Capacity=306.66 cfs 0.49 cfs 0.42 cfs Type II 24-hr 1yr Rainfall=2.40"Boat Landing Printed 7/7/2014Prepared by HP Page 11HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Reach 10R: to Minnewashta PROPOSED Inflow Area =2.697 ac,47.31% Impervious, Inflow Depth > 0.53" for 1yr event Inflow=1.03 cfs @ 12.20 hrs, Volume=0.119 af Outflow=1.03 cfs @ 12.20 hrs, Volume=0.119 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Reach 10R: to Minnewashta PROPOSED Inflow Outflow Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 1 0 Inflow Area=2.697 ac 1.03 cfs1.03 cfs Type II 24-hr 1yr Rainfall=2.40"Boat Landing Printed 7/7/2014Prepared by HP Page 12HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Pond 1P: Rain Garden Inflow Area =0.396 ac,94.44% Impervious, Inflow Depth > 1.84" for 1yr event Inflow=1.10 cfs @ 12.01 hrs, Volume=0.061 af Outflow=0.50 cfs @ 12.16 hrs, Volume=0.030 af, Atten= 54%, Lag= 9.2 min Discarded=0.01 cfs @ 12.16 hrs, Volume=0.006 af Primary=0.49 cfs @ 12.16 hrs, Volume=0.024 af Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 965.11' @ 12.16 hrs Surf.Area= 0.023 ac Storage= 0.033 af Plug-Flow detention time= 160.7 min calculated for 0.030 af (50% of inflow) Center-of-Mass det. time= 77.2 min ( 828.3 - 751.1 ) VolumeInvertAvail.StorageStorage Description #1963.00'0.059 af Custom Stage Data (Prismatic) Listed below (Recalc) ElevationSurf.AreaInc.StoreCum.Store (feet)(acres)(acre-feet)(acre-feet) 963.000.0090.0000.000 964.000.0150.0120.012 965.000.0220.0180.030 966.000.0350.0280.059 DeviceRouting InvertOutlet Devices #1Primary965.00'5.0' long x 2.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 3.50 Coef. (English) 2.54 2.61 2.61 2.60 2.66 2.70 2.77 2.89 2.88 2.85 3.07 3.20 3.32 #2Discarded963.00'0.300 in/hr Exfiltration over Surface area Discarded OutFlow Max=0.01 cfs @ 12.16 hrs HW=965.11' (Free Discharge) 2=Exfiltration (Exfiltration Controls 0.01 cfs) Primary OutFlow Max=0.46 cfs @ 12.16 hrs HW=965.11' (Free Discharge) 1=Broad-Crested Rectangular Weir (Weir Controls 0.46 cfs @ 0.84 fps) Type II 24-hr 1yr Rainfall=2.40"Boat Landing Printed 7/7/2014Prepared by HP Page 13HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Pond 1P: Rain Garden Inflow Outflow Discarded Primary Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 1 0 Inflow Area=0.396 ac Peak Elev=965.11' Storage=0.033 af 1.10 cfs 0.50 cfs 0.01 cfs 0.49 cfs Type II 24-hr 1yr Rainfall=2.40"Boat Landing Printed 7/7/2014Prepared by HP Page 14HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Pond 2P: Rain Garden w/ Yard Drain Inflow Area =1.426 ac,76.72% Impervious, Inflow Depth > 1.02" for 1yr event Inflow=1.92 cfs @ 12.02 hrs, Volume=0.121 af Outflow=1.90 cfs @ 12.03 hrs, Volume=0.109 af, Atten= 1%, Lag= 0.8 min Discarded=0.00 cfs @ 12.03 hrs, Volume=0.003 af Primary=1.89 cfs @ 12.03 hrs, Volume=0.106 af Secondary=0.00 cfs @ 5.00 hrs, Volume=0.000 af Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 949.69' @ 12.03 hrs Surf.Area= 0.014 ac Storage= 0.014 af Plug-Flow detention time= 47.0 min calculated for 0.109 af (90% of inflow) Center-of-Mass det. time= 14.1 min ( 811.6 - 797.5 ) VolumeInvertAvail.StorageStorage Description #1948.00'0.039 af Custom Stage Data (Prismatic) Listed below (Recalc) ElevationSurf.AreaInc.StoreCum.Store (feet)(acres)(acre-feet)(acre-feet) 948.000.0040.0000.000 949.000.0090.0060.006 950.000.0160.0120.019 951.000.0240.0200.039 DeviceRouting InvertOutlet Devices #1Primary946.00'15.0" Round Culvert L= 71.0' Ke= 0.500 Inlet / Outlet Invert= 946.00' / 945.00' S= 0.0141 '/' Cc= 0.900 n= 0.014, Flow Area= 1.23 sf #2Secondary950.30'20.0' long x 20.0' breadth Broad-Crested Rectangular Weir 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 #3Device 1949.50'27.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4Discarded948.00'0.300 in/hr Exfiltration over Surface area Discarded OutFlow Max=0.00 cfs @ 12.03 hrs HW=949.69' (Free Discharge) 4=Exfiltration (Exfiltration Controls 0.00 cfs) Primary OutFlow Max=1.84 cfs @ 12.03 hrs HW=949.69' (Free Discharge) 1=Culvert (Passes 1.84 cfs of 9.87 cfs potential flow) 3=Orifice/Grate (Weir Controls 1.84 cfs @ 1.41 fps) Secondary OutFlow Max=0.00 cfs @ 5.00 hrs HW=948.00' (Free Discharge) 2=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Type II 24-hr 1yr Rainfall=2.40"Boat Landing Printed 7/7/2014Prepared by HP Page 15HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Pond 2P: Rain Garden w/ Yard Drain Inflow Outflow Discarded Primary Secondary Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 2 1 0 Inflow Area=1.426 ac Peak Elev=949.69' Storage=0.014 af 1.92 cfs1.90 cfs 0.00 cfs 1.89 cfs 0.00 cfs Type II 24-hr 1yr Rainfall=2.40"Boat Landing Printed 7/7/2014Prepared by HP Page 16HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Pond 4P: Stormwater Basin Inflow Area =1.735 ac,64.21% Impervious, Inflow Depth > 0.76" for 1yr event Inflow=1.94 cfs @ 12.03 hrs, Volume=0.110 af Outflow=0.98 cfs @ 12.22 hrs, Volume=0.106 af, Atten= 49%, Lag= 11.1 min Primary=0.98 cfs @ 12.22 hrs, Volume=0.106 af Secondary=0.00 cfs @ 5.00 hrs, Volume=0.000 af Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Starting Elev= 946.00' Surf.Area= 0.045 ac Storage= 0.034 af Peak Elev= 946.51' @ 12.22 hrs Surf.Area= 0.056 ac Storage= 0.060 af (0.026 af above start) Plug-Flow detention time= 143.7 min calculated for 0.072 af (65% of inflow) Center-of-Mass det. time= 21.5 min ( 833.0 - 811.5 ) VolumeInvertAvail.StorageStorage Description #1945.00'0.245 af Custom Stage Data (Prismatic) Listed below (Recalc) ElevationSurf.AreaInc.StoreCum.Store (feet)(acres)(acre-feet)(acre-feet) 945.000.0230.0000.000 946.000.0450.0340.034 947.000.0660.0550.089 948.000.0780.0720.161 949.000.0900.0840.245 DeviceRouting InvertOutlet Devices #1Primary946.00'12.0" Round Culvert L= 100.0' Ke= 0.500 Inlet / Outlet Invert= 946.00' / 945.00' S= 0.0100 '/' Cc= 0.900 n= 0.013, Flow Area= 0.79 sf #2Secondary948.50'10.0' long x 10.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64 Primary OutFlow Max=0.98 cfs @ 12.22 hrs HW=946.51' (Free Discharge) 1=Culvert (Inlet Controls 0.98 cfs @ 2.43 fps) Secondary OutFlow Max=0.00 cfs @ 5.00 hrs HW=946.00' (Free Discharge) 2=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Type II 24-hr 1yr Rainfall=2.40"Boat Landing Printed 7/7/2014Prepared by HP Page 17HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Pond 4P: Stormwater Basin Inflow Outflow Primary Secondary Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 2 1 0 Inflow Area=1.735 ac Peak Elev=946.51' Storage=0.060 af 1.94 cfs 0.98 cfs0.98 cfs 0.00 cfs Type II 24-hr 1yr Rainfall=2.40"Boat Landing Printed 7/7/2014Prepared by HP Page 18HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Pond 7P: Inflow Area =0.162 ac,100.00% Impervious, Inflow Depth > 2.02" for 1yr event Inflow=0.47 cfs @ 12.01 hrs, Volume=0.027 af Outflow=0.06 cfs @ 12.39 hrs, Volume=0.010 af, Atten= 87%, Lag= 23.0 min Discarded=0.01 cfs @ 12.39 hrs, Volume=0.006 af Primary=0.05 cfs @ 12.39 hrs, Volume=0.004 af Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 952.51' @ 12.39 hrs Surf.Area= 0.026 ac Storage= 0.017 af Plug-Flow detention time= 219.5 min calculated for 0.010 af (38% of inflow) Center-of-Mass det. time= 111.1 min ( 850.2 - 739.2 ) VolumeInvertAvail.StorageStorage Description #1951.00'0.089 af Custom Stage Data (Prismatic) Listed below (Recalc) ElevationSurf.AreaInc.StoreCum.Store (feet)(acres)(acre-feet)(acre-feet) 951.000.0050.0000.000 952.000.0110.0080.008 953.000.0400.0250.033 954.000.0700.0550.089 DeviceRouting InvertOutlet Devices #1Primary952.50'10.0' long x 5.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef. (English) 2.34 2.50 2.70 2.68 2.68 2.66 2.65 2.65 2.65 2.65 2.67 2.66 2.68 2.70 2.74 2.79 2.88 #2Discarded951.00'0.300 in/hr Exfiltration over Surface area Discarded OutFlow Max=0.01 cfs @ 12.39 hrs HW=952.51' (Free Discharge) 2=Exfiltration (Exfiltration Controls 0.01 cfs) Primary OutFlow Max=0.04 cfs @ 12.39 hrs HW=952.51' (Free Discharge) 1=Broad-Crested Rectangular Weir (Weir Controls 0.04 cfs @ 0.27 fps) Type II 24-hr 1yr Rainfall=2.40"Boat Landing Printed 7/7/2014Prepared by HP Page 19HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Pond 7P: Inflow Outflow Discarded Primary Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 0.52 0.5 0.48 0.46 0.44 0.42 0.4 0.38 0.36 0.34 0.32 0.3 0.28 0.26 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 Inflow Area=0.162 ac Peak Elev=952.51' Storage=0.017 af 0.47 cfs 0.06 cfs 0.01 cfs 0.05 cfs Type II 24-hr 10yr Rainfall=4.20"Boat Landing Printed 7/7/2014Prepared by HP Page 20HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=0.396 ac 94.44% Impervious Runoff Depth>3.48"Subcatchment 3S: Tc=10.0 min CN=96 Runoff=2.01 cfs 0.115 af Runoff Area=1.030 ac 69.90% Impervious Runoff Depth>2.63"Subcatchment 5S: Tc=10.0 min CN=87 Runoff=4.31 cfs 0.226 af Runoff Area=0.309 ac 6.47% Impervious Runoff Depth>0.91"Subcatchment 6S: Tc=10.0 min CN=63 Runoff=0.45 cfs 0.024 af Runoff Area=0.162 ac 100.00% Impervious Runoff Depth>3.65"Subcatchment 8S: Tc=10.0 min CN=98 Runoff=0.84 cfs 0.049 af Runoff Area=2.697 ac 0.00% Impervious Runoff Depth>1.52"Subcatchment 9S: Existing Boat Launch Tc=10.0 min CN=73 Runoff=6.79 cfs 0.342 af Runoff Area=0.800 ac 0.00% Impervious Runoff Depth>0.81"Subcatchment 10S: north boat launch - Tc=10.0 min CN=61 Runoff=1.00 cfs 0.054 af Avg. Flow Depth=0.16' Max Vel=3.35 fps Inflow=1.92 cfs 0.077 afReach 8R: swale n=0.030 L=230.0' S=0.0674 '/' Capacity=306.66 cfs Outflow=1.85 cfs 0.077 af Inflow=4.85 cfs 0.383 afReach 10R: to Minnewashta PROPOSED Outflow=4.85 cfs 0.383 af Peak Elev=965.28' Storage=0.037 af Inflow=2.01 cfs 0.115 afPond 1P: Rain Garden Discarded=0.01 cfs 0.007 af Primary=1.92 cfs 0.077 af Outflow=1.93 cfs 0.084 af Peak Elev=949.91' Storage=0.018 af Inflow=5.98 cfs 0.303 afPond 2P: Rain Garden w/ Yard Drain Discarded=0.00 cfs 0.004 af Primary=5.97 cfs 0.287 af Secondary=0.00 cfs 0.000 af Outflow=5.98 cfs 0.291 af Peak Elev=947.37' Storage=0.114 af Inflow=6.42 cfs 0.311 afPond 4P: Stormwater Basin Primary=3.42 cfs 0.304 af Secondary=0.00 cfs 0.000 af Outflow=3.42 cfs 0.304 af Peak Elev=952.60' Storage=0.020 af Inflow=0.84 cfs 0.049 afPond 7P: Discarded=0.01 cfs 0.007 af Primary=0.79 cfs 0.025 af Outflow=0.79 cfs 0.032 af Total Runoff Area = 5.394 ac Runoff Volume = 0.809 af Average Runoff Depth = 1.80" 76.34% Pervious = 4.118 ac 23.66% Impervious = 1.276 ac Type II 24-hr 10yr Rainfall=4.20"Boat Landing Printed 7/7/2014Prepared by HP Page 21HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment 3S: Runoff=2.01 cfs @ 12.01 hrs, Volume=0.115 af, Depth>3.48" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10yr Rainfall=4.20" Area (ac)CNDescription *0.37498 *0.02261 0.39696Weighted Average 0.0225.56% Pervious Area 0.37494.44% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Subcatchment 3S: Runoff Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 2 1 0 Type II 24-hr 10yr Rainfall=4.20" Runoff Area=0.396 ac Runoff Volume=0.115 af Runoff Depth>3.48" Tc=10.0 min CN=96 2.01 cfs Type II 24-hr 10yr Rainfall=4.20"Boat Landing Printed 7/7/2014Prepared by HP Page 22HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment 5S: Runoff=4.31 cfs @ 12.01 hrs, Volume=0.226 af, Depth>2.63" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10yr Rainfall=4.20" Area (ac)CNDescription *0.72098 *0.31061 1.03087Weighted Average 0.31030.10% Pervious Area 0.72069.90% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Subcatchment 5S: Runoff Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 4 3 2 1 0 Type II 24-hr 10yr Rainfall=4.20" Runoff Area=1.030 ac Runoff Volume=0.226 af Runoff Depth>2.63" Tc=10.0 min CN=87 4.31 cfs Type II 24-hr 10yr Rainfall=4.20"Boat Landing Printed 7/7/2014Prepared by HP Page 23HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment 6S: Runoff=0.45 cfs @ 12.03 hrs, Volume=0.024 af, Depth>0.91" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10yr Rainfall=4.20" Area (ac)CNDescription *0.02098 *0.28961 0.30963Weighted Average 0.28993.53% Pervious Area 0.0206.47% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Subcatchment 6S: Runoff Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 0.5 0.48 0.46 0.44 0.42 0.4 0.38 0.36 0.34 0.32 0.3 0.28 0.26 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 Type II 24-hr 10yr Rainfall=4.20" Runoff Area=0.309 ac Runoff Volume=0.024 af Runoff Depth>0.91" Tc=10.0 min CN=63 0.45 cfs Type II 24-hr 10yr Rainfall=4.20"Boat Landing Printed 7/7/2014Prepared by HP Page 24HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment 8S: Runoff=0.84 cfs @ 12.01 hrs, Volume=0.049 af, Depth>3.65" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10yr Rainfall=4.20" Area (ac)CNDescription *0.16298 0.162100.00% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Subcatchment 8S: Runoff Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 0.9 0.85 0.8 0.75 0.7 0.65 0.6 0.55 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Type II 24-hr 10yr Rainfall=4.20" Runoff Area=0.162 ac Runoff Volume=0.049 af Runoff Depth>3.65" Tc=10.0 min CN=98 0.84 cfs Type II 24-hr 10yr Rainfall=4.20"Boat Landing Printed 7/7/2014Prepared by HP Page 25HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment 9S: Existing Boat Launch Runoff=6.79 cfs @ 12.02 hrs, Volume=0.342 af, Depth>1.52" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10yr Rainfall=4.20" Area (ac)CNDescription *0.60085existing south parking lot 1.29761>75% Grass cover, Good, HSG B *0.80085existing north parking lot 2.69773Weighted Average 2.697100.00% Pervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Subcatchment 9S: Existing Boat Launch Runoff Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 7 6 5 4 3 2 1 0 Type II 24-hr 10yr Rainfall=4.20" Runoff Area=2.697 ac Runoff Volume=0.342 af Runoff Depth>1.52" Tc=10.0 min CN=73 6.79 cfs Type II 24-hr 10yr Rainfall=4.20"Boat Landing Printed 7/7/2014Prepared by HP Page 26HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment 10S: north boat launch - gravel removed Runoff=1.00 cfs @ 12.04 hrs, Volume=0.054 af, Depth>0.81" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 10yr Rainfall=4.20" Area (ac)CNDescription *0.80061 0.800100.00% Pervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Subcatchment 10S: north boat launch - gravel removed Runoff Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 1 0 Type II 24-hr 10yr Rainfall=4.20" Runoff Area=0.800 ac Runoff Volume=0.054 af Runoff Depth>0.81" Tc=10.0 min CN=61 1.00 cfs Type II 24-hr 10yr Rainfall=4.20"Boat Landing Printed 7/7/2014Prepared by HP Page 27HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Reach 8R: swale Inflow Area =0.396 ac,94.44% Impervious, Inflow Depth > 2.35" for 10yr event Inflow=1.92 cfs @ 12.04 hrs, Volume=0.077 af Outflow=1.85 cfs @ 12.07 hrs, Volume=0.077 af, Atten= 4%, Lag= 1.9 min Routing by Stor-Ind+Trans method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Max. Velocity= 3.35 fps, Min. Travel Time= 1.1 min Avg. Velocity = 1.10 fps, Avg. Travel Time= 3.5 min Peak Storage= 131 cf @ 12.05 hrs Average Depth at Peak Storage= 0.16' Bank-Full Depth= 2.00' Flow Area= 22.0 sf, Capacity= 306.66 cfs 3.00' x 2.00' deep channel, n= 0.030 Side Slope Z-value= 4.0 '/' Top Width= 19.00' Length= 230.0' Slope= 0.0674 '/' Inlet Invert= 965.50', Outlet Invert= 950.00' ‡ Reach 8R: swale Inflow Outflow Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 2 1 0 Inflow Area=0.396 ac Avg. Flow Depth=0.16' Max Vel=3.35 fps n=0.030 L=230.0' S=0.0674 '/' Capacity=306.66 cfs 1.92 cfs1.85 cfs Type II 24-hr 10yr Rainfall=4.20"Boat Landing Printed 7/7/2014Prepared by HP Page 28HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Reach 10R: to Minnewashta PROPOSED Inflow Area =2.697 ac,47.31% Impervious, Inflow Depth > 1.71" for 10yr event Inflow=4.85 cfs @ 12.08 hrs, Volume=0.383 af Outflow=4.85 cfs @ 12.08 hrs, Volume=0.383 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Reach 10R: to Minnewashta PROPOSED Inflow Outflow Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 5 4 3 2 1 0 Inflow Area=2.697 ac 4.85 cfs4.85 cfs Type II 24-hr 10yr Rainfall=4.20"Boat Landing Printed 7/7/2014Prepared by HP Page 29HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Pond 1P: Rain Garden Inflow Area =0.396 ac,94.44% Impervious, Inflow Depth > 3.48" for 10yr event Inflow=2.01 cfs @ 12.01 hrs, Volume=0.115 af Outflow=1.93 cfs @ 12.04 hrs, Volume=0.084 af, Atten= 4%, Lag= 1.8 min Discarded=0.01 cfs @ 12.04 hrs, Volume=0.007 af Primary=1.92 cfs @ 12.04 hrs, Volume=0.077 af Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 965.28' @ 12.04 hrs Surf.Area= 0.026 ac Storage= 0.037 af Plug-Flow detention time= 110.6 min calculated for 0.084 af (73% of inflow) Center-of-Mass det. time= 49.3 min ( 790.5 - 741.2 ) VolumeInvertAvail.StorageStorage Description #1963.00'0.059 af Custom Stage Data (Prismatic) Listed below (Recalc) ElevationSurf.AreaInc.StoreCum.Store (feet)(acres)(acre-feet)(acre-feet) 963.000.0090.0000.000 964.000.0150.0120.012 965.000.0220.0180.030 966.000.0350.0280.059 DeviceRouting InvertOutlet Devices #1Primary965.00'5.0' long x 2.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 3.50 Coef. (English) 2.54 2.61 2.61 2.60 2.66 2.70 2.77 2.89 2.88 2.85 3.07 3.20 3.32 #2Discarded963.00'0.300 in/hr Exfiltration over Surface area Discarded OutFlow Max=0.01 cfs @ 12.04 hrs HW=965.28' (Free Discharge) 2=Exfiltration (Exfiltration Controls 0.01 cfs) Primary OutFlow Max=1.88 cfs @ 12.04 hrs HW=965.28' (Free Discharge) 1=Broad-Crested Rectangular Weir (Weir Controls 1.88 cfs @ 1.35 fps) Type II 24-hr 10yr Rainfall=4.20"Boat Landing Printed 7/7/2014Prepared by HP Page 30HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Pond 1P: Rain Garden Inflow Outflow Discarded Primary Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 2 1 0 Inflow Area=0.396 ac Peak Elev=965.28' Storage=0.037 af 2.01 cfs 1.93 cfs 0.01 cfs 1.92 cfs Type II 24-hr 10yr Rainfall=4.20"Boat Landing Printed 7/7/2014Prepared by HP Page 31HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Pond 2P: Rain Garden w/ Yard Drain Inflow Area =1.426 ac,76.72% Impervious, Inflow Depth > 2.55" for 10yr event Inflow=5.98 cfs @ 12.03 hrs, Volume=0.303 af Outflow=5.98 cfs @ 12.04 hrs, Volume=0.291 af, Atten= 0%, Lag= 0.6 min Discarded=0.00 cfs @ 12.04 hrs, Volume=0.004 af Primary=5.97 cfs @ 12.04 hrs, Volume=0.287 af Secondary=0.00 cfs @ 5.00 hrs, Volume=0.000 af Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 949.91' @ 12.04 hrs Surf.Area= 0.015 ac Storage= 0.018 af Plug-Flow detention time= 25.1 min calculated for 0.291 af (96% of inflow) Center-of-Mass det. time= 9.8 min ( 785.8 - 776.0 ) VolumeInvertAvail.StorageStorage Description #1948.00'0.039 af Custom Stage Data (Prismatic) Listed below (Recalc) ElevationSurf.AreaInc.StoreCum.Store (feet)(acres)(acre-feet)(acre-feet) 948.000.0040.0000.000 949.000.0090.0060.006 950.000.0160.0120.019 951.000.0240.0200.039 DeviceRouting InvertOutlet Devices #1Primary946.00'15.0" Round Culvert L= 71.0' Ke= 0.500 Inlet / Outlet Invert= 946.00' / 945.00' S= 0.0141 '/' Cc= 0.900 n= 0.014, Flow Area= 1.23 sf #2Secondary950.30'20.0' long x 20.0' breadth Broad-Crested Rectangular Weir 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 #3Device 1949.50'27.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4Discarded948.00'0.300 in/hr Exfiltration over Surface area Discarded OutFlow Max=0.00 cfs @ 12.04 hrs HW=949.90' (Free Discharge) 4=Exfiltration (Exfiltration Controls 0.00 cfs) Primary OutFlow Max=5.84 cfs @ 12.04 hrs HW=949.90' (Free Discharge) 1=Culvert (Passes 5.84 cfs of 10.17 cfs potential flow) 3=Orifice/Grate (Weir Controls 5.84 cfs @ 2.07 fps) Secondary OutFlow Max=0.00 cfs @ 5.00 hrs HW=948.00' (Free Discharge) 2=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Type II 24-hr 10yr Rainfall=4.20"Boat Landing Printed 7/7/2014Prepared by HP Page 32HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Pond 2P: Rain Garden w/ Yard Drain Inflow Outflow Discarded Primary Secondary Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 6 5 4 3 2 1 0 Inflow Area=1.426 ac Peak Elev=949.91' Storage=0.018 af 5.98 cfs5.98 cfs 0.00 cfs 5.97 cfs 0.00 cfs Type II 24-hr 10yr Rainfall=4.20"Boat Landing Printed 7/7/2014Prepared by HP Page 33HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Pond 4P: Stormwater Basin Inflow Area =1.735 ac,64.21% Impervious, Inflow Depth > 2.15" for 10yr event Inflow=6.42 cfs @ 12.04 hrs, Volume=0.311 af Outflow=3.42 cfs @ 12.18 hrs, Volume=0.304 af, Atten= 47%, Lag= 8.4 min Primary=3.42 cfs @ 12.18 hrs, Volume=0.304 af Secondary=0.00 cfs @ 5.00 hrs, Volume=0.000 af Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Starting Elev= 946.00' Surf.Area= 0.045 ac Storage= 0.034 af Peak Elev= 947.37' @ 12.17 hrs Surf.Area= 0.070 ac Storage= 0.114 af (0.080 af above start) Plug-Flow detention time= 68.3 min calculated for 0.270 af (87% of inflow) Center-of-Mass det. time= 16.0 min ( 804.1 - 788.1 ) VolumeInvertAvail.StorageStorage Description #1945.00'0.245 af Custom Stage Data (Prismatic) Listed below (Recalc) ElevationSurf.AreaInc.StoreCum.Store (feet)(acres)(acre-feet)(acre-feet) 945.000.0230.0000.000 946.000.0450.0340.034 947.000.0660.0550.089 948.000.0780.0720.161 949.000.0900.0840.245 DeviceRouting InvertOutlet Devices #1Primary946.00'12.0" Round Culvert L= 100.0' Ke= 0.500 Inlet / Outlet Invert= 946.00' / 945.00' S= 0.0100 '/' Cc= 0.900 n= 0.013, Flow Area= 0.79 sf #2Secondary948.50'10.0' long x 10.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64 Primary OutFlow Max=3.41 cfs @ 12.18 hrs HW=947.36' (Free Discharge) 1=Culvert (Barrel Controls 3.41 cfs @ 4.34 fps) Secondary OutFlow Max=0.00 cfs @ 5.00 hrs HW=946.00' (Free Discharge) 2=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Type II 24-hr 10yr Rainfall=4.20"Boat Landing Printed 7/7/2014Prepared by HP Page 34HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Pond 4P: Stormwater Basin Inflow Outflow Primary Secondary Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 7 6 5 4 3 2 1 0 Inflow Area=1.735 ac Peak Elev=947.37' Storage=0.114 af 6.42 cfs 3.42 cfs3.42 cfs 0.00 cfs Type II 24-hr 10yr Rainfall=4.20"Boat Landing Printed 7/7/2014Prepared by HP Page 35HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Pond 7P: Inflow Area =0.162 ac,100.00% Impervious, Inflow Depth > 3.65" for 10yr event Inflow=0.84 cfs @ 12.01 hrs, Volume=0.049 af Outflow=0.79 cfs @ 12.05 hrs, Volume=0.032 af, Atten= 5%, Lag= 2.4 min Discarded=0.01 cfs @ 12.05 hrs, Volume=0.007 af Primary=0.79 cfs @ 12.05 hrs, Volume=0.025 af Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 952.60' @ 12.05 hrs Surf.Area= 0.029 ac Storage= 0.020 af Plug-Flow detention time= 131.3 min calculated for 0.032 af (65% of inflow) Center-of-Mass det. time= 60.1 min ( 794.1 - 734.0 ) VolumeInvertAvail.StorageStorage Description #1951.00'0.089 af Custom Stage Data (Prismatic) Listed below (Recalc) ElevationSurf.AreaInc.StoreCum.Store (feet)(acres)(acre-feet)(acre-feet) 951.000.0050.0000.000 952.000.0110.0080.008 953.000.0400.0250.033 954.000.0700.0550.089 DeviceRouting InvertOutlet Devices #1Primary952.50'10.0' long x 5.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef. (English) 2.34 2.50 2.70 2.68 2.68 2.66 2.65 2.65 2.65 2.65 2.67 2.66 2.68 2.70 2.74 2.79 2.88 #2Discarded951.00'0.300 in/hr Exfiltration over Surface area Discarded OutFlow Max=0.01 cfs @ 12.05 hrs HW=952.60' (Free Discharge) 2=Exfiltration (Exfiltration Controls 0.01 cfs) Primary OutFlow Max=0.77 cfs @ 12.05 hrs HW=952.60' (Free Discharge) 1=Broad-Crested Rectangular Weir (Weir Controls 0.77 cfs @ 0.75 fps) Type II 24-hr 10yr Rainfall=4.20"Boat Landing Printed 7/7/2014Prepared by HP Page 36HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Pond 7P: Inflow Outflow Discarded Primary Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 0.9 0.85 0.8 0.75 0.7 0.65 0.6 0.55 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Inflow Area=0.162 ac Peak Elev=952.60' Storage=0.020 af 0.84 cfs 0.79 cfs 0.01 cfs 0.79 cfs Type II 24-hr 100yr Rainfall=6.00"Boat Landing Printed 7/7/2014Prepared by HP Page 37HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=0.396 ac 94.44% Impervious Runoff Depth>5.12"Subcatchment 3S: Tc=10.0 min CN=96 Runoff=2.91 cfs 0.169 af Runoff Area=1.030 ac 69.90% Impervious Runoff Depth>4.23"Subcatchment 5S: Tc=10.0 min CN=87 Runoff=6.74 cfs 0.363 af Runoff Area=0.309 ac 6.47% Impervious Runoff Depth>1.97"Subcatchment 6S: Tc=10.0 min CN=63 Runoff=1.00 cfs 0.051 af Runoff Area=0.162 ac 100.00% Impervious Runoff Depth>5.27"Subcatchment 8S: Tc=10.0 min CN=98 Runoff=1.21 cfs 0.071 af Runoff Area=2.697 ac 0.00% Impervious Runoff Depth>2.84"Subcatchment 9S: Existing Boat Launch Tc=10.0 min CN=73 Runoff=12.62 cfs 0.639 af Runoff Area=0.800 ac 0.00% Impervious Runoff Depth>1.81"Subcatchment 10S: north boat launch - Tc=10.0 min CN=61 Runoff=2.38 cfs 0.121 af Avg. Flow Depth=0.19' Max Vel=3.79 fps Inflow=2.80 cfs 0.131 afReach 8R: swale n=0.030 L=230.0' S=0.0674 '/' Capacity=306.66 cfs Outflow=2.71 cfs 0.131 af Inflow=7.43 cfs 0.687 afReach 10R: to Minnewashta PROPOSED Outflow=7.43 cfs 0.687 af Peak Elev=965.36' Storage=0.039 af Inflow=2.91 cfs 0.169 afPond 1P: Rain Garden Discarded=0.01 cfs 0.007 af Primary=2.80 cfs 0.131 af Outflow=2.81 cfs 0.138 af Peak Elev=950.04' Storage=0.020 af Inflow=9.23 cfs 0.494 afPond 2P: Rain Garden w/ Yard Drain Discarded=0.00 cfs 0.004 af Primary=9.22 cfs 0.477 af Secondary=0.00 cfs 0.000 af Outflow=9.22 cfs 0.482 af Peak Elev=948.27' Storage=0.183 af Inflow=10.22 cfs 0.528 afPond 4P: Stormwater Basin Primary=4.41 cfs 0.520 af Secondary=0.00 cfs 0.000 af Outflow=4.41 cfs 0.520 af Peak Elev=952.63' Storage=0.021 af Inflow=1.21 cfs 0.071 afPond 7P: Discarded=0.01 cfs 0.007 af Primary=1.15 cfs 0.047 af Outflow=1.16 cfs 0.054 af Total Runoff Area = 5.394 ac Runoff Volume = 1.413 af Average Runoff Depth = 3.14" 76.34% Pervious = 4.118 ac 23.66% Impervious = 1.276 ac Type II 24-hr 100yr Rainfall=6.00"Boat Landing Printed 7/7/2014Prepared by HP Page 38HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment 3S: Runoff=2.91 cfs @ 12.01 hrs, Volume=0.169 af, Depth>5.12" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 100yr Rainfall=6.00" Area (ac)CNDescription *0.37498 *0.02261 0.39696Weighted Average 0.0225.56% Pervious Area 0.37494.44% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Subcatchment 3S: Runoff Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 3 2 1 0 Type II 24-hr 100yr Rainfall=6.00" Runoff Area=0.396 ac Runoff Volume=0.169 af Runoff Depth>5.12" Tc=10.0 min CN=96 2.91 cfs Type II 24-hr 100yr Rainfall=6.00"Boat Landing Printed 7/7/2014Prepared by HP Page 39HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment 5S: Runoff=6.74 cfs @ 12.01 hrs, Volume=0.363 af, Depth>4.23" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 100yr Rainfall=6.00" Area (ac)CNDescription *0.72098 *0.31061 1.03087Weighted Average 0.31030.10% Pervious Area 0.72069.90% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Subcatchment 5S: Runoff Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 7 6 5 4 3 2 1 0 Type II 24-hr 100yr Rainfall=6.00" Runoff Area=1.030 ac Runoff Volume=0.363 af Runoff Depth>4.23" Tc=10.0 min CN=87 6.74 cfs Type II 24-hr 100yr Rainfall=6.00"Boat Landing Printed 7/7/2014Prepared by HP Page 40HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment 6S: Runoff=1.00 cfs @ 12.02 hrs, Volume=0.051 af, Depth>1.97" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 100yr Rainfall=6.00" Area (ac)CNDescription *0.02098 *0.28961 0.30963Weighted Average 0.28993.53% Pervious Area 0.0206.47% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Subcatchment 6S: Runoff Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 1 0 Type II 24-hr 100yr Rainfall=6.00" Runoff Area=0.309 ac Runoff Volume=0.051 af Runoff Depth>1.97" Tc=10.0 min CN=63 1.00 cfs Type II 24-hr 100yr Rainfall=6.00"Boat Landing Printed 7/7/2014Prepared by HP Page 41HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment 8S: Runoff=1.21 cfs @ 12.01 hrs, Volume=0.071 af, Depth>5.27" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 100yr Rainfall=6.00" Area (ac)CNDescription *0.16298 0.162100.00% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Subcatchment 8S: Runoff Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 1 0 Type II 24-hr 100yr Rainfall=6.00" Runoff Area=0.162 ac Runoff Volume=0.071 af Runoff Depth>5.27" Tc=10.0 min CN=98 1.21 cfs Type II 24-hr 100yr Rainfall=6.00"Boat Landing Printed 7/7/2014Prepared by HP Page 42HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment 9S: Existing Boat Launch Runoff=12.62 cfs @ 12.02 hrs, Volume=0.639 af, Depth>2.84" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 100yr Rainfall=6.00" Area (ac)CNDescription *0.60085existing south parking lot 1.29761>75% Grass cover, Good, HSG B *0.80085existing north parking lot 2.69773Weighted Average 2.697100.00% Pervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Subcatchment 9S: Existing Boat Launch Runoff Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Type II 24-hr 100yr Rainfall=6.00" Runoff Area=2.697 ac Runoff Volume=0.639 af Runoff Depth>2.84" Tc=10.0 min CN=73 12.62 cfs Type II 24-hr 100yr Rainfall=6.00"Boat Landing Printed 7/7/2014Prepared by HP Page 43HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment 10S: north boat launch - gravel removed Runoff=2.38 cfs @ 12.02 hrs, Volume=0.121 af, Depth>1.81" Runoff by SCS TR-20 method, UH=SCS, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24-hr 100yr Rainfall=6.00" Area (ac)CNDescription *0.80061 0.800100.00% Pervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Subcatchment 10S: north boat launch - gravel removed Runoff Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 2 1 0 Type II 24-hr 100yr Rainfall=6.00" Runoff Area=0.800 ac Runoff Volume=0.121 af Runoff Depth>1.81" Tc=10.0 min CN=61 2.38 cfs Type II 24-hr 100yr Rainfall=6.00"Boat Landing Printed 7/7/2014Prepared by HP Page 44HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Reach 8R: swale Inflow Area =0.396 ac,94.44% Impervious, Inflow Depth > 3.97" for 100yr event Inflow=2.80 cfs @ 12.03 hrs, Volume=0.131 af Outflow=2.71 cfs @ 12.06 hrs, Volume=0.131 af, Atten= 3%, Lag= 1.6 min Routing by Stor-Ind+Trans method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Max. Velocity= 3.79 fps, Min. Travel Time= 1.0 min Avg. Velocity = 1.22 fps, Avg. Travel Time= 3.2 min Peak Storage= 169 cf @ 12.05 hrs Average Depth at Peak Storage= 0.19' Bank-Full Depth= 2.00' Flow Area= 22.0 sf, Capacity= 306.66 cfs 3.00' x 2.00' deep channel, n= 0.030 Side Slope Z-value= 4.0 '/' Top Width= 19.00' Length= 230.0' Slope= 0.0674 '/' Inlet Invert= 965.50', Outlet Invert= 950.00' ‡ Reach 8R: swale Inflow Outflow Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 3 2 1 0 Inflow Area=0.396 ac Avg. Flow Depth=0.19' Max Vel=3.79 fps n=0.030 L=230.0' S=0.0674 '/' Capacity=306.66 cfs 2.80 cfs2.71 cfs Type II 24-hr 100yr Rainfall=6.00"Boat Landing Printed 7/7/2014Prepared by HP Page 45HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Reach 10R: to Minnewashta PROPOSED Inflow Area =2.697 ac,47.31% Impervious, Inflow Depth > 3.06" for 100yr event Inflow=7.43 cfs @ 12.05 hrs, Volume=0.687 af Outflow=7.43 cfs @ 12.05 hrs, Volume=0.687 af, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Reach 10R: to Minnewashta PROPOSED Inflow Outflow Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 8 7 6 5 4 3 2 1 0 Inflow Area=2.697 ac 7.43 cfs7.43 cfs Type II 24-hr 100yr Rainfall=6.00"Boat Landing Printed 7/7/2014Prepared by HP Page 46HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Pond 1P: Rain Garden Inflow Area =0.396 ac,94.44% Impervious, Inflow Depth > 5.12" for 100yr event Inflow=2.91 cfs @ 12.01 hrs, Volume=0.169 af Outflow=2.81 cfs @ 12.03 hrs, Volume=0.138 af, Atten= 3%, Lag= 1.7 min Discarded=0.01 cfs @ 12.03 hrs, Volume=0.007 af Primary=2.80 cfs @ 12.03 hrs, Volume=0.131 af Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 965.36' @ 12.03 hrs Surf.Area= 0.027 ac Storage= 0.039 af Plug-Flow detention time= 95.3 min calculated for 0.138 af (82% of inflow) Center-of-Mass det. time= 43.4 min ( 780.3 - 736.9 ) VolumeInvertAvail.StorageStorage Description #1963.00'0.059 af Custom Stage Data (Prismatic) Listed below (Recalc) ElevationSurf.AreaInc.StoreCum.Store (feet)(acres)(acre-feet)(acre-feet) 963.000.0090.0000.000 964.000.0150.0120.012 965.000.0220.0180.030 966.000.0350.0280.059 DeviceRouting InvertOutlet Devices #1Primary965.00'5.0' long x 2.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 3.50 Coef. (English) 2.54 2.61 2.61 2.60 2.66 2.70 2.77 2.89 2.88 2.85 3.07 3.20 3.32 #2Discarded963.00'0.300 in/hr Exfiltration over Surface area Discarded OutFlow Max=0.01 cfs @ 12.03 hrs HW=965.35' (Free Discharge) 2=Exfiltration (Exfiltration Controls 0.01 cfs) Primary OutFlow Max=2.74 cfs @ 12.03 hrs HW=965.35' (Free Discharge) 1=Broad-Crested Rectangular Weir (Weir Controls 2.74 cfs @ 1.54 fps) Type II 24-hr 100yr Rainfall=6.00"Boat Landing Printed 7/7/2014Prepared by HP Page 47HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Pond 1P: Rain Garden Inflow Outflow Discarded Primary Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 3 2 1 0 Inflow Area=0.396 ac Peak Elev=965.36' Storage=0.039 af 2.91 cfs2.81 cfs 0.01 cfs 2.80 cfs Type II 24-hr 100yr Rainfall=6.00"Boat Landing Printed 7/7/2014Prepared by HP Page 48HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Pond 2P: Rain Garden w/ Yard Drain Inflow Area =1.426 ac,76.72% Impervious, Inflow Depth > 4.16" for 100yr event Inflow=9.23 cfs @ 12.02 hrs, Volume=0.494 af Outflow=9.22 cfs @ 12.03 hrs, Volume=0.482 af, Atten= 0%, Lag= 0.6 min Discarded=0.00 cfs @ 12.03 hrs, Volume=0.004 af Primary=9.22 cfs @ 12.03 hrs, Volume=0.477 af Secondary=0.00 cfs @ 5.00 hrs, Volume=0.000 af Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 950.04' @ 12.03 hrs Surf.Area= 0.016 ac Storage= 0.020 af Plug-Flow detention time= 18.3 min calculated for 0.482 af (98% of inflow) Center-of-Mass det. time= 8.5 min ( 774.1 - 765.6 ) VolumeInvertAvail.StorageStorage Description #1948.00'0.039 af Custom Stage Data (Prismatic) Listed below (Recalc) ElevationSurf.AreaInc.StoreCum.Store (feet)(acres)(acre-feet)(acre-feet) 948.000.0040.0000.000 949.000.0090.0060.006 950.000.0160.0120.019 951.000.0240.0200.039 DeviceRouting InvertOutlet Devices #1Primary946.00'15.0" Round Culvert L= 71.0' Ke= 0.500 Inlet / Outlet Invert= 946.00' / 945.00' S= 0.0141 '/' Cc= 0.900 n= 0.014, Flow Area= 1.23 sf #2Secondary950.30'20.0' long x 20.0' breadth Broad-Crested Rectangular Weir 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 #3Device 1949.50'27.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4Discarded948.00'0.300 in/hr Exfiltration over Surface area Discarded OutFlow Max=0.00 cfs @ 12.03 hrs HW=950.03' (Free Discharge) 4=Exfiltration (Exfiltration Controls 0.00 cfs) Primary OutFlow Max=9.00 cfs @ 12.03 hrs HW=950.03' (Free Discharge) 1=Culvert (Passes 9.00 cfs of 10.36 cfs potential flow) 3=Orifice/Grate (Weir Controls 9.00 cfs @ 2.39 fps) Secondary OutFlow Max=0.00 cfs @ 5.00 hrs HW=948.00' (Free Discharge) 2=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Type II 24-hr 100yr Rainfall=6.00"Boat Landing Printed 7/7/2014Prepared by HP Page 49HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Pond 2P: Rain Garden w/ Yard Drain Inflow Outflow Discarded Primary Secondary Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 10 9 8 7 6 5 4 3 2 1 0 Inflow Area=1.426 ac Peak Elev=950.04' Storage=0.020 af 9.23 cfs9.22 cfs 0.00 cfs 9.22 cfs 0.00 cfs Type II 24-hr 100yr Rainfall=6.00"Boat Landing Printed 7/7/2014Prepared by HP Page 50HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Pond 4P: Stormwater Basin Inflow Area =1.735 ac,64.21% Impervious, Inflow Depth > 3.65" for 100yr event Inflow=10.22 cfs @ 12.03 hrs, Volume=0.528 af Outflow=4.41 cfs @ 12.19 hrs, Volume=0.520 af, Atten= 57%, Lag= 9.5 min Primary=4.41 cfs @ 12.19 hrs, Volume=0.520 af Secondary=0.00 cfs @ 5.00 hrs, Volume=0.000 af Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Starting Elev= 946.00' Surf.Area= 0.045 ac Storage= 0.034 af Peak Elev= 948.27' @ 12.19 hrs Surf.Area= 0.081 ac Storage= 0.183 af (0.149 af above start) Plug-Flow detention time= 54.5 min calculated for 0.484 af (92% of inflow) Center-of-Mass det. time= 17.7 min ( 794.7 - 777.0 ) VolumeInvertAvail.StorageStorage Description #1945.00'0.245 af Custom Stage Data (Prismatic) Listed below (Recalc) ElevationSurf.AreaInc.StoreCum.Store (feet)(acres)(acre-feet)(acre-feet) 945.000.0230.0000.000 946.000.0450.0340.034 947.000.0660.0550.089 948.000.0780.0720.161 949.000.0900.0840.245 DeviceRouting InvertOutlet Devices #1Primary946.00'12.0" Round Culvert L= 100.0' Ke= 0.500 Inlet / Outlet Invert= 946.00' / 945.00' S= 0.0100 '/' Cc= 0.900 n= 0.013, Flow Area= 0.79 sf #2Secondary948.50'10.0' long x 10.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64 Primary OutFlow Max=4.40 cfs @ 12.19 hrs HW=948.27' (Free Discharge) 1=Culvert (Barrel Controls 4.40 cfs @ 5.61 fps) Secondary OutFlow Max=0.00 cfs @ 5.00 hrs HW=946.00' (Free Discharge) 2=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Type II 24-hr 100yr Rainfall=6.00"Boat Landing Printed 7/7/2014Prepared by HP Page 51HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Pond 4P: Stormwater Basin Inflow Outflow Primary Secondary Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 11 10 9 8 7 6 5 4 3 2 1 0 Inflow Area=1.735 ac Peak Elev=948.27' Storage=0.183 af 10.22 cfs 4.41 cfs4.41 cfs 0.00 cfs Type II 24-hr 100yr Rainfall=6.00"Boat Landing Printed 7/7/2014Prepared by HP Page 52HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Summary for Pond 7P: Inflow Area =0.162 ac,100.00% Impervious, Inflow Depth > 5.27" for 100yr event Inflow=1.21 cfs @ 12.01 hrs, Volume=0.071 af Outflow=1.16 cfs @ 12.03 hrs, Volume=0.054 af, Atten= 4%, Lag= 1.7 min Discarded=0.01 cfs @ 12.03 hrs, Volume=0.007 af Primary=1.15 cfs @ 12.03 hrs, Volume=0.047 af Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 952.63' @ 12.03 hrs Surf.Area= 0.029 ac Storage= 0.021 af Plug-Flow detention time= 110.1 min calculated for 0.054 af (76% of inflow) Center-of-Mass det. time= 51.0 min ( 783.0 - 732.1 ) VolumeInvertAvail.StorageStorage Description #1951.00'0.089 af Custom Stage Data (Prismatic) Listed below (Recalc) ElevationSurf.AreaInc.StoreCum.Store (feet)(acres)(acre-feet)(acre-feet) 951.000.0050.0000.000 952.000.0110.0080.008 953.000.0400.0250.033 954.000.0700.0550.089 DeviceRouting InvertOutlet Devices #1Primary952.50'10.0' long x 5.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef. (English) 2.34 2.50 2.70 2.68 2.68 2.66 2.65 2.65 2.65 2.65 2.67 2.66 2.68 2.70 2.74 2.79 2.88 #2Discarded951.00'0.300 in/hr Exfiltration over Surface area Discarded OutFlow Max=0.01 cfs @ 12.03 hrs HW=952.63' (Free Discharge) 2=Exfiltration (Exfiltration Controls 0.01 cfs) Primary OutFlow Max=1.12 cfs @ 12.03 hrs HW=952.63' (Free Discharge) 1=Broad-Crested Rectangular Weir (Weir Controls 1.12 cfs @ 0.85 fps) Type II 24-hr 100yr Rainfall=6.00"Boat Landing Printed 7/7/2014Prepared by HP Page 53HydroCAD® 10.00 s/n 00883 © 2012 HydroCAD Software Solutions LLC Pond 7P: Inflow Outflow Discarded Primary Hydrograph Time (hours) 201918171615141312111098765 Fl o w ( c f s ) 1 0 Inflow Area=0.162 ac Peak Elev=952.63' Storage=0.021 af 1.21 cfs1.16 cfs 0.01 cfs 1.15 cfs