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HomeMy WebLinkAbout2023-10-18 Stanted Updated Plan Review - Elliott Engineering Response Stantec Consulting Services Inc Sta ntec 733 Marquette Avenue Suite 1000,Minneapolis MN 55402-2309 October 18, 2023 at I t � File: 193800151 Ttia Attention: Mr. Jacob Rife City of Oak Park Heights 14168 Oak Park Blvd. Oak Park Height, MN 55082 Reference: Croixview Holdings— Updated Plan Review Dear Jacob: As requested, we have reviewed the revised plans dated October 11, 2023 regarding the proposed office/warehouse project at 5416 Stagecoach Trail North. Following are our revised comments and/or recommendations: Sheet Cl —Grading and Erosion Control Plan 1. The plans should include additional detail regardingthe retaining wall, including base material and draintile outlet locations. Note added: Any oter wall type, inc. segmental wall not allowed without review and approvel by city engineer 2. A significant portion of the southerly lot will be inundated with water prior to reaching the EOF of 782.0 for Rainwater Garden #1. EOF lowered to 781.5 Sheet C2—Site Utilities and Stormwater 1. The plans should note that the proposed 6"water service should be connected to the existing 8" watermain by open-cutting and installing an 8" x 6"tee. The City does not allow wet tap connections. Note added to plan C2 2. A 6" Gate Valve and Box on the proposed water service line should be placed on the west side of the road between the existing curb line and the future trail. Added to C2 3. The Fire Marshal shall review the proposed watermain and determine the need for a fire hydrant on the subject property. Sheet C3—Site Plan 1. The Site Plan should denote the locations of the different concrete sections (i.e. distinguish between concrete pavement, walks, aprons). Noted on C3 2. The proposed B612 Concrete Curb &Gutter Detail should note whether it refers to proposed parking lot curb, or Stagecoach Trail curb patching. Noted on C 3. Refer to the Fire Department review of fire lanes and circulation. Completed October 18, 2023 Mr.Jacob Rife Page 2 of 2 Reference: Croixview Holdings—Updated Plan Review Storm Sewer/Storm Water Management 1. Provide documentation of Middle St. Croix Watershed Management Organization (MSCWMO) approval. Will provide 2. Revise infiltration rate. Test Pits#6 and #7 are the only test pit locations that are within the boundary of the proposed underground TDA system. Each test pit has a limiting soil layer of silty sand (SP-SM) per the supplied soil borings submitted in July of 2023 as part of the CUP submittal. Per the MPCA's Minnesota Stormwater Manual Design Infiltration Rates table this soil is between a Hydrologic Soil Group A and B. Both SP (0.8 inches/hr)and SM (0.45 inches/hr) soils have lower than 1 inch/hour infiltration rates. Since this soil is a combination soil, a composite infiltration rate should be used, which would be the average of the SP and SM infiltration rates. If these soil borings are inaccurate, please provide updated borings that support SP-SM not being present in the infiltration area. General Notes Infiltration Outlet lowered 0.2' per .45"/hr drawdown in 48 hours, Updated Stormater calculations and report provided. 1. Washington County needs to approve the proposed access dimensions and locations. 2. Review of parking, lighting, landscaping, or building items is by others. 3. The Owner shall be responsible for obtaining all required permits. 4. The City reserves the right to inspect the construction of the project. The City should be notified of and be included in the preconstruction meeting. If you have any questions or require further information, please do not hesitate to contact me. Regards, Stantec Consulting Services Inc. 4)-1/1 Lee M. Mann. P' MN,WI,CA Principal Phone: 612-712-2085 Lee.Mann@stantec.corn c. file Julie Hultman, Building Official Andrew Kegley, Director of Public Works Scott Richards,City Planner EXHIBIT A EASEMENT DESCRIPTION An Easement for Stormwater Management Facilities purposes over, under and across that part of the following described property: Parcel 1: The South 262 feet of the North 494 feet of the East 233 feet of the Northeast 1/4 of the Southwest'% of Section 3, Township 29, Range 20, excepting therefrom that part taken for highway; AND Parcel 2: All that part of the Northwest Quarter of the Southeast Quarter of Section 3, Township 29 North, Range 20 West, described as follows: Commencing at the center of Section 3, Township 29 North, Range 20 West and running thence South 1 degree 30' East along the centerline of said Section 3 for a distance of 232 feet to the point of beginning of the land hereby conveyed; from said point of beginning continuing South on the aforesaid line extended in a straight line to the point where it intersects the west boundary of the Stillwater and Point Douglas Road also known as Highway 21; running thence Northeasterly along the West boundary of said Stillwater and Point Douglas Road to a point where it intersects a line parallel to and 232 feet South of the North line of the Southeast Quarter of Section 3, Township 29 North, Range 20; running thence Westerly in a straight line to the point of beginning, being a triangular piece of land adjacent to Easterly of and having as its northern boundary the extended North boundary of that land conveyed to Lester F. Bell and La Verne G. Bell, by deed dated August 24, 1957, recorded December 30, 1957 in Book 210 of Deeds, page 339, excepting therefrom that part taken for highway. said easement is described as follows: COMMENCING at the southwest corner of the above described parcel; thence on an assumed bearing of North 89 degrees 36 minutes 56 seconds East along the south line of above described parcel a distance of 222.26 feet to the southeast corner of the above described parcel; thence northerly 8.62 feet along the easterly line of the above described parcel being a EASEMENT AREA = non-tangential curve concave to the east having a radius of 1,465.40 feet CONTAINING 22,414 and a central angle of 00 degrees 20 minutes 13 seconds and a chord which SQUARE FEET OR 0.51 bears North 03 degrees 42 minutes 16 seconds East to the POINT OF ACRES, MORE OR LESS BEGINNING of the easement to be described; thence South 89 degrees 27 minutes 01 seconds West a distance of 216.24 feet; thence North 02 degrees SEE EXHIBIT B FOR THE 03 minutes 46 seconds West a distance of 68.38 feet; thence South 89 EASEMENT DETAIL degrees 55 minutes 08 seconds East a distance of a distance of 3.01 feet; SKETCH thence North 00 degrees 55 minutes 35 seconds West a distance of 72.47 feet; thence North 19 degrees 51 minutes 28 seconds West a distance of 36.11 feet; thence North 70 degrees 08 minutes 32 seconds East a distance of 10.00 feet; thence South 19 degrees 51 minutes 28 seconds East a distance of 37.78 feet; thence South 00 degrees 55 minutes 35 seconds East a distance of 74.31 feet; thence South 89 degrees 55 minutes 08 seconds East a distance of 74.18 feet; thence South 00 degrees 07 minutes 34 Suite#200 seconds East a distance of 21.35 feet; thence North 89 degrees 36 minutes Q 1970 Northwestern Ave. 56 seconds East a distance of 73.41 feet; thence North 00 degrees 23 Stillwater,MN 55082 Phone 651.275.8969 minutes 04 seconds West a distance of 120.31 feet; thence North 89 degrees dan@cssurvey 59 minutes 58 seconds East a distance of 44.12 feet; thence North 00 net degrees 23 minutes 04 seconds West a distance of 25.51 feet; thence North 89 degrees 36 minutes 56 seconds East a distance of 40.60 feet to the easterly line of the above described parcel; thence southerly 193.22 feet along said easterly line being a non-tangential curve concave to the east having a radius of 1,465.40 feet and a central angle of 07 degrees 33 minutes 18 seconds and a chord which bears South 07 degrees 39 minutes 02 seconds West to the POINT OF BEGINNING. CORNERSTONE LANE) SURVEYING, INC t .it EX I BIT B EASEMENT DETAIL SKETCH SEE EXHIBIT A FOR THE STORMWATER MANAGEMENT FACILITIES EASEMENT DESCRIPTION / Z _- f -I - 233 - -N Z J J cel al al rG 3 a a = :52"� o a d 1.„\cn 0°080, , " .10 0 o N89°36'56"E / �i o x,40 60 ;- I / 1' N Z [�/•00( I "� �,c° r'r", N89°5Y '5 " v°cA:iT \1o ,..-Zc / •imoe} W O wOw=a-' �N�Ni° IND jl— rN,WOOONi� O � .s J�~~ 0�1 ///z/W I��,5O�O ",I Owni 0 u) (j g o°)(On^I _ -,.. W O�w z Jii IN��� � ` rT,l 3 cv�cnf-------1p,7W ' '11 C (5(-5 U Q O '- 77 74.1877-�- 1 4.-4./,.. i. . /S89455'08”E-h, / / /I / CO \- . v I cry 1o/d n EASEMENT �� N89°36'56"E ARESC.BRG.=NO3 42'16"E S89 0� ! W/ 0Z /// 4=0°2013" IL�1724/ - / R=18.6240 I ' ----P.O.B. I / )1222.26 N89°36'56"E j SOUTH LINE OF THE NORTH 1 / -4c14.00 FEET OF- THE NE 1/4 OF THE SW 1/4 OF PROJECT LOCATION: SEC. 3, T29, R20 5416 STAGECOACH TRL. N. ' A77'\., AFTON, MN 55001 / PROJECT NO. ZZ696A DENOTES EASEMENT AREA PID#0302920310002 ©CERTIFICATION: NORTH Suite#200 1970 Northwestern Ave. 0 400 1970 MN 55082 I hereby certify that this survey,plan Phone 651.275.8969 or report was prepared by me or dan@cssurvey under my direct supervision and that I net am a duly licensed Land Surveyor 7:7 under the laws of the State of Minnesota. EASEMENT AREA SHOWN WAS PROVIDED BY ELLIOTT DESIGN BUILD,INC. 7514 OLIVER AVE S0 ANIEL L.THURMES MINNEAPOLIS,MN 55423 License.No. 25718 (612) 220-0152 CORNERSTONE Date 10-13-23 LANE> SURVEYING, INC E -ELLIOTT E July 10, 2023 (Revised 10-20-23) RE: Stormwater Management Report for Croixview Office Warehouse 5416 Stagecoach Trail N, Oak Park Heights, MN Presented By: Stephen Mastey ASLA, PLA, LEED AP Landscape Architecture Incorporated 3511 Lake Elmo Avenue N Lake Elmo, MN 55042 Lance Elliott, PE Elliott Design Build, Inc. 7514 Oliver Ave. S Minneapolis, MN 55424 For the proposed development of a new office/warehouse facility located 5416 Stagecoach Trail N, the following stormwater management information is provided. The project will include disturbance of approximately 1.4 acres and will add 40,500 SF (0.93 acres) of total new impervious surfaces. The specific requirements and responses to previous review memos are addressed herein: Infiltration/Water Quality: Requirement: Capture and infiltrate 1.1"for all proposed impervious: 40,500 sf"1.1/12=3,713 CF Provided: 7,442 CF (2.0 times required amount) through implementation of underground tire derived aggregate (TDA) infiltration basin. Also, note, that although the MIDS performance goal is not required since the project adds less than one acre of impervious, the proposed BMP's not only meet this requirement, but essentially eliminates any phosphorous or suspended solids from leaving the site. Rate Control: Requirement: Proposed runoff rates to not exceed existing. Results: For rate control for the 2, 10, and 100-year events, all proposed rates are lower than existing conditions. Below is a chart showing the proposed runoff rates compared to existing. 2-Year 10-Year 100-Year Existing Proposed Existing Proposed Existing Proposed 0.13 cfs 0.03 cfs 1.01 cfs .28 cfs 4.83 cfs 1.92 cfs 5305 Wooddale Ave, Edina, MN 55424 Phone: (612) 220-0152 www.elliottdestgribuild.com Site Drainage Description and Design Summary: The existing property is a vacant lot consisting of lawn with trees and no hard surface present. The soil report (attached) indicates that the site has about 1' of sandy topsoil and the underlying soils are silty sand (SP-SM) with some gravel present. The soil report indicates that the soils would be ideal for infiltration, and we estimate the infiltration rates to be between 2-6 inches per hour. The stormwater calculations in this report were limited to .45 inch per hour to be conservative due to the presence of SP-SM soils on the site and to build in an additional factor of safety. The existing stormwater runoff (See Drainage Map attached) on the property generally drains to the west and north towards the northwest corner of the site and then drains off the property towards a large wetland and Perro Pond. For the post-construction condition, please see the included civil and landscape plans for reference. All of the new impervious surfaces drain to a newly constructed underground infiltration basin utilizing tire derived aggregate (TDA) with 50% storage volume capacity. Two rainwater gardens are proposed to provide pre-treatment prior to water entering the underground system through outlet structures located in the gardens. The parking lot surface drains through curb cuts and is treated with inlet pre-treatments devices that provide an additional level of pre- treatment to catch sediment and debris prior to water draining to the rainwater gardens. The building roof will drain directly to the underground basin through roof drains and underground piping. Pre-treatment is provided by 24" sumps in the structures that the roof drains into prior to entering the underground basin. The basin is designed to fully capture a 100-year storm and the normal water level outlet is controlled by a 6" outlet which controls to level retained for infiltration. The basin fully contains both the 2-year and 10-year events for complete infiltration without any outflow from the site. The captured water with draw down within 48 hours based on a conservative 0.54" per hour calculation. As you saw in the results above, the system is oversized to provide over 2.0 times the minimum amount of infiltration volume required by the watershed regulations. Due to the oversizing of the TDA system, the proposed runoff rates for the 2-Year, 10-Year, and 100-Year storms are all significantly less than existing. In the end, the overall site drainage patterns will remain generally unchanged, as all proposed runoff will leave the site in the same location in the NW corner of the site as the existing conditions, albeit, significantly less than existing due to the extensive BMP implementation. Thank you for taking the time to review this stormwater submittal and please contact me if you have any questions. Sincerely, Stephen Mastey, PLA Lance Elliott, P.E. Professional Landscape Architect Civil Engineer 5305 Wooddale Ave, Edina, MN 55424 Phone: (612)220-0152 www.eilioildesignbuild.com , , , --, R Rill ' 1 i 1 w .. , 0 g ... , z, ; . 11 .,, 2---- ,21',- <o_ o, z .-1, z, , 0 ,z 0... , ,,, PE l...1 A g CO 1 1 '' o2 q , Lo, g , g.2 N i i p 1,ilit; .! 1188 •.2-. 8 , 2 LLI 1 ..„ ._ , 1 r'N , ; u.I „ —y --------- 1:__--, _--' _------; ---- ,_— --- ------- --------------_ ---- .,„...." 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'1 1 ' ,. \ . 5 , 5' ' " 51 51."1"5--7, it K\ 1S 2S • 3S Existing Proposed braining to Proposed jbreen Space Infiltrati n Basin NOT Drai/ ing to BMP's , ' \ , / 1 P \ Underground DA Storage Ai 10,- -.6 3 L Combined Proposed r---N ' Su bcat Reach ch 'on• !Link Routing Diagram for Siegfried 10-20-23 L_I L \ Prepared by LG, Printed 10/20/2023 HydroCAD®10.00-26 s/n 07614 ©2020 HydroCAD Software Solutions LLC Siegfried 10-20-23 Prepared by LG Printed 10/20/2023 HydroCAD® 10.00-26 s/n 07614 ©2020 HydroCAD Software Solutions LLC Page 2 Area Listing (all nodes) Area CN Description (sq-ft) (subcatchment-numbers) 16,000 98 Building (2S) 86,086 56 INPUT PER WATERSHED (1S, 2S, 3S) 24,500 98 Paving (2S) 126,586 69 TOTAL AREA Siegfried 10-20-23 Prepared by LG Printed 10/20/2023 HydroCAD® 10.00-26 s/n 07614 ©2020 HydroCAD Software Solutions LLC Page 3 Soil Listing (all nodes) Area Soil Subcatchment (sq-ft) Group Numbers 0 HSG A 0 HSG B 0 HSG C 0 HSG D 126,586 Other 1S, 2S, 3S 126,586 TOTAL AREA Siegfried 10-20-23 Prepared by LG Printed 10/20/2023 HydroCAD® 10.00-26 s/n 07614 ©2020 HydroCAD Software Solutions LLC Page 4 Ground Covers (all nodes) HSG-A HSG-B HSG-C HSG-D Other Total Ground Subcc (sq-ft) (sq-ft) (sq-ft) (sq-ft) (sq-ft) (sq-ft) Cover Numb 0 0 0 0 16,000 16,000 Building 0 0 0 0 86,086 86,086 INPUT PER WATERSHED 0 0 0 0 24,500 24,500 Paving 0 0 0 0 126,586 126,586 TOTAL AREA Siegfried 10-20-23 Prepared by LG Printed 10/20/2023 HydroCAD® 10.00-26 s/n 07614 ©2020 HydroCAD Software Solutions LLC Page 5 Pipe Listing (all nodes) Line# Node In-Invert Out-Invert Length Slope n Diam/Width Height Inside-Fill Number (feet) (feet) (feet) (ft/ft) (inches) (inches) (inches) 1 2S 0.00 0.00 462.0 0.0050 0.010 15.0 0.0 0.0 2 3S 0.00 0.00 462.0 0.0050 0.010 15.0 0.0 0.0 3 1P 775.00 774.00 100.0 0.0100 0.010 12.0 0.0 0.0 Siegfried 10-20-23 MSE 24-hr 3 2-Year Rainfall=2.85" Prepared by LG Printed 10/20/2023 HydroCAD® 10.00-26 s/n 07614 ©2020 HydroCAD Software Solutions LLC Page 6 Time span=0.00-30.00 hrs, dt=0.05 hrs, 601 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchmentl S: Existing Runoff Area=63,293 sf 0.00% Impervious Runoff Depth=0.18" Flow Length=354' Tc=13.0 min CN=56 Runoff=0.13 cfs 944 cf Subcatchment2S: ProposedDrainingto Runoff Area=51,493 sf 78.65% Impervious Runoff Depth=1.76" Flow Length=662' Tc=4.6 min CN=89 Runoff=3.86 cfs 7,573 cf Subcatchment3S: ProposedGreen Space NOT RunoffArea=11,800 sf 0.00% Impervious Runoff Depth=0.18" Flow Length=662' Tc=4.6 min CN=56 Runoff=0.03 cfs 176 cf Pond 1P: UndergroundTDAStorage Peak Elev=775.28' Storage=5,088 cf Inflow=3.86 cfs 7,573 cf Discarded=0.09 cfs 6,019 cf Primary=0.00 cfs 0 cf Outflow=0.09 cfs 6,019 cf Link 3L:CombinedProposed Inflow=0.03 cfs 176 cf Primary=0.03 cfs 176 cf Total Runoff Area = 126,586 sf Runoff Volume = 8,693 cf Average Runoff Depth = 0.82" 68.01% Pervious = 86,086 sf 31.99% Impervious = 40,500 sf Siegfried 10-20-23 MSE 24-hr 3 2-Year Rainfall=2.85" Prepared by LG Printed 10/20/2023 HydroCAD® 10.00-26 sin 07614 ©2020 HydroCAD Software Solutions LLC Page 7 Summary for Subcatchment 1S: Existing Runoff = 0.13 cfs @ 12.41 hrs, Volume= 944 cf, Depth= 0.18" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.05 hrs MSE 24-hr 3 2-Year Rainfall=2.85" Area (sf) CN Description 63,293 56 INPUT PER WATERSHED 63,293 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 11.6 50 0.0100 0.07 Sheet Flow, Sheet Flow Grass: Dense n= 0.240 P2= 2.80" 1.4 304 0.0500 3.60 Shallow Concentrated Flow, Shallow Concentrated Flow Unpaved Kv= 16.1 fps 13.0 354 Total Subcatchment 1S: Existing Hydrograph - 0.13 cfs 0.14 _ _ 0.13_ x MSE 24-hr 3 0.12-, 0.11: 2-Year Rainfall=2.85" 01 Runoff Area=63,293 sf 0.09 o.oa 944 Runoff Volume;= 0.077 2 2 Runoff Depth=0.16" LL 0.064 Flow Length=354' - 0.05- in--0Tc=13.0 min-- 0 03 .03: /t CN =56 0.02- ✓... -7 0.01 o 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours) Siegfried 10-20-23 MSE 24-hr 3 2-Year Rainfall=2.85" Prepared by LG Printed 10/20/2023 HydroCAD® 10.00-26 s/n 07614 ©2020 HydroCAD Software Solutions LLC Page 8 Summary for Subcatchment 2S: Proposed Draining to Infiltration Basin [49] Hint: Tc<2dt may require smaller dt Runoff = 3.86 cfs @ 12.11 hrs, Volume= 7,573 cf, Depth= 1.76" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.05 hrs MSE 24-hr 3 2-Year Rainfall=2.85" Area (sf) CN Description 16,000 98 Building 24,500 98 Paving 10,993 56 INPUT PER WATERSHED 51,493 89 Weighted Average 10,993 21.35% Pervious Area 40,500 78.65% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 1.7 100 0.0100 0.98 Sheet Flow, Roof Smooth surfaces n= 0.011 P2= 2.80" 1.3 100 0.0200 1.29 Sheet Flow, Parking Smooth surfaces n= 0.011 P2= 2.80" 1.6 462 0.0050 4.84 5.94 Pipe Channel, 15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31' n= 0.010 Concrete pipe, straight & clean 4.6 662 Total Siegfried 10-20-23 MSE 24-hr 3 2-Year Rainfall=2.85" Prepared by LG Printed 10/20/2023 HydroCAD® 10.00-26 s/n 07614 ©2020 HydroCAD Software Solutions LLC Page 9 Subcatchment 2S: Proposed Draining to Infiltration Basin Z. Runoff 4 3.86 cfs MSE 24 hr 3 2-Year Rainfall=2.85" 3- Runoff Area=51 493 sf Runoff Volume-=7,573cf Runoff Depth=1;.76" j,e o 2- Flow Length=662' Tc=4.6m i n Gh=89 1 *02;07' . .Adm 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours) Siegfried 10-20-23 MSE 24-hr 3 2-Year Rainfall=2.85" Prepared by LG Printed 10/20/2023 HydroCAD® 10.00-26 s/n 07614 ©2020 HydroCAD Software Solutions LLC Page 10 Summary for Subcatchment 3S: Proposed Green Space NOT Draining to BMP's [49] Hint: Tc<2dt may require smaller dt Runoff = 0.03 cfs@ 12.23 hrs, Volume= 176 cf, Depth= 0.18" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.05 hrs MSE 24-hr 3 2-Year Rainfall=2.85" Area (sf) CN Description 11,800 56 INPUT PER WATERSHED 11,800 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 1.7 100 0.0100 0.98 Sheet Flow, Roof Smooth surfaces n= 0.011 P2= 2.80" 1.3 100 0.0200 1.29 Sheet Flow, Parking Smooth surfaces n= 0.011 P2= 2.80" 1.6 462 0.0050 4.84 5.94 Pipe Channel, 15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31' n= 0.010 Concrete pipe, straight & clean 4.6 662 Total Subcatchment 3S: Proposed Green Space NOT Draining to BMP's Hydrograph f 0.028 0.03 cfs 0.026; MSE 24-hr 3 0.024: ; 2-Year-Rainfall=2 85"- 0.022 0.02= Runoff Area=11 800 sf Runoff Volume=176-cf- u 0.016-' 0.014 Runoff-Depth=O 1-8` - 0.012 Flow Length=662'_ 0.01 . Tc=4 & 0.008= 11111'1 0.006_ C N=56 0.004 0.002 r 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours) Siegfried 10-20-23 MSE 24-hr 3 2-Year Rainfall=2.85" Prepared by LG Printed 10/20/2023 HydroCAD® 10.00-26 s/n 07614 ©2020 HydroCAD Software Solutions LLC Page 11 Summary for Pond 1P: Underground TDA Storage Inflow Area = 51,493 sf, 78.65%Impervious, Inflow Depth = 1.76" for 2-Year event Inflow = 3.86 cfs @ 12.11 hrs, Volume= 7,573 cf Outflow = 0.09 cfs @ 15.03 hrs, Volume= 6,019 cf, Atten= 98°/g Lag= 174.9 min Discarded = 0.09 cfs @ 15.03 hrs, Volume= 6,019 cf Primary = 0.00 cfs @ 0.00 hrs, Volume= 0 cf Routing by Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.05 hrs Peak Elev= 775.28'@ 15.03 hrs Surf.Area= 8,715 sf Storage= 5,088 cf Plug-Flow detention time=482.9 min calculated for 6,009 cf(79% of inflow) Center-of-Mass det. time=420.5 min ( 1,214.5 - 794.0 ) Volume Invert Avail.Storage Storage Description #1 774.00' 25,429 cf Custom Stage Data (Prismatkt. sted below(Recalc) 50,858 cf Overall x 50.0% Voids Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 774.00 7,245 0 0 775.00 8,394 7,820 7,820 776.00 9,561 8,978 16,797 777.00 10,746 10,154 26,951 778.00 11,949 11,348 38,298 779.00 13,170 12,560 50,858 Device Routing Invert Outlet Devices #1 Device 3 775.80' 6.0" Vert. Orifice/Grate C= 0.600 #2 Discarded 774.00' 0.450 in/hr Exfiltration over Surface area #3 Primary 775.00' 12.0" Round Culvert L= 100.0' CMP, projecting, no headwall, Ke=0.900 Inlet/Outlet Invert=775.00'/774.00' S= 0.0100'/' Cc= 0.900 n= 0.010 PVC, smooth interior, Flow Area=0.79 sf #4 Device 3 777.50' 12.0" Vert. Orifice/Grate C= 0.600 Discarded OutFlowMax=0.09 cfs @ 15.03 hrs HW=775.28' (Free Discharge) L2=Exfiltration(Exfiltration Controls 0.09 cfs) Primary OutFlowMax=0.00 cfs @ 0.00 hrs HW=774.00' (Free Discharge) 4-3=Culvert ( Controls 0.00 cfs) L41=Orifice/Grate( Controls 0.00 cfs) =Orifice/Grate( Controls 0.00 cfs) Siegfried 10-20-23 MSE 24-hr 3 2-Year Rainfall=2.85" Prepared by LG Printed 10/20/2023 HydroCAD® 10.00-26 s/n 07614 ©2020 HydroCAD Software Solutions LLC Page 12 Pond 1P: Underground TDA Storage Hydregrap m`Y Inflow 3 86 cfs ;Outflow / - 1— w Inflow Area=51,493 sf Prmaryed 4 t ` Peak EIev=775.28' ., Storage=5,088 cf wAu o 2... in fit 1 0 09 cfs ' 0.00 cfs ,''‘''='`'''‘''N-�� . 13-Or ` / ,'' ,/ /z//77,-/(4,w/4,-/-,4,-;,7„,77/74,✓`.///'///°/':. ' -/�� ,`'` 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 28 20 Time (h15ours16 )17 18 19 20 21 22 23 24 25 26 27 9 3 Siegfried 10-20-23MSE 24-hr 3 2-Year Rainfall=2.85" Prepared by LG Printed 10/20/2023 HydroCAD® 10.00-26 s/n 07614 ©2020 HydroCAD Software Solutions LLC Page 13 Summary for Link 3L: Combined Proposed Inflow Area = 63,293 sf, 63.99%Impervious, Inflow Depth = 0.03" for 2-Year event Inflow = 0.03 cfs @ 12.23 hrs, Volume= 176 cf Primary = 0.03 cfs @ 12.23 hrs, Volume= 176 cf, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-30.00 hrs, dt= 0.05 hrs Link 3L: Combined Proposed Hydrograph / - +- + Inflow 0 03 Inflow Area=63 293 sf ���m�� 0.02s 0.03 cfs s, 0 026 I 0.024 0.022 * + 0.02., i _ 0.018-1 - _ --------- --- ------ y - - - - -- -- --------- - I 0.016'., 7 7 0 0.0147 LL 1 1 0.012 a 0.01 : ,. + 0.0087 , '',,,,,'::,,,,: ,4.,,,,,,,,,,,,:4, ./., , dr.„,,,,_,,,,,,,, , dr 0.006 a - - ,-- - 0.004 0.000 / �fi e 0 1 2T";/">)?45/71 ..7 6 7 8 9 10 11 12 13 14'e15 16 1'7 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours) Siegfried 10-20-23 MSE 24-hr 3 10-Year Rainfall=4.22" Prepared by LG Printed 10/20/2023 HydroCAD® 10.00-26 s/n 07614 ©2020 HydroCAD Software Solutions LLC Page 14 Time span=0.00-30.00 hrs, dt=0.05 hrs, 601 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchmentl S: Existing Runoff Area=63,293 sf 0.00% Impervious Runoff Depth=0.67" Flow Length=354' Tc=13.0 min CN=56 Runoff=1.01 cfs 3,522 cf Subcatchment2S: ProposedDrainingto Runoff Area=51,493 sf 78.65% Impervious Runoff Depth=3.03" Flow Length=662' Tc=4.6 min CN=89 Runoff=6.46 cfs 13,003 cf Subcatchment3S: ProposedGreenSpace NOT Runoff Area=11,800 sf 0.00% Impervious Runoff Depth=0.67" Flow Length=662' Tc=4.6 min CN=56 Runoff=0.28 cfs 657 cf Pond 1P: UndergroundTDA Storage Peak EIev=776.05' Storage=8,656 cf Inflow=6.46 cfs 13,003 cf Discarded=0.10 cfs 6,891 cf Primary=0.17 cfs 1,612 cf Outflow=0.27 cfs 8,503 cf Link3L: CombinedProposed Inflow=0.28 cfs 2,269 cf Primary=0.28 cfs 2,269 cf Total Runoff Area = 126,586 sf Runoff Volume = 17,181 cf Average Runoff Depth = 1.63" 68.01% Pervious = 86,086 sf 31.99% Impervious = 40,500 sf Siegfried 10-20-23 MSE 24-hr 3 10-Year Rainfall=4.22" Prepared by LG Printed 10/20/2023 HydroCAD® 10.00-26 s/n 07614 ©2020 HydroCAD Software Solutions LLC Page 15 Summary for Subcatchment 1S: Existing Runoff = 1.01 cfs @ 12.25 hrs, Volume= 3,522 cf, Depth= 0.67" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.05 hrs MSE 24-hr 3 10-Year Rainfall=4.22" Area (sf) CN Description 63,293 56 INPUT PER WATERSHED 63,293 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 11.6 50 0.0100 0.07 Sheet Flow, Sheet Flow Grass: Dense n= 0.240 P2= 2.80" 1.4 304 0.0500 3.60 Shallow Concentrated Flow, Shallow Concentrated Flow Unpaved Kv= 16.1 fps 13.0 354 Total Subcatchment 1S: Existing Hydrograph 10 Runoff 1.01 cfs 1 MSE 24-hr 3 10-Year Rainfall=4.22" 11 R, Runoff Area=63,293 sf Runoff Volume=3,522 cf Runoff Depth=0.67" l Flow Length=354' Tc=13.0 min CN=56 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours) Siegfried 10-20-23 MSE 24-hr 3 10-Year Rainfall=4.22" Prepared by LG Printed 10/20/2023 HydroCAD® 10.00-26 s/n 07614 ©2020 HydroCAD Software Solutions LLC Page 16 Summary for Subcatchment 2S: Proposed Draining to Infiltration Basin [49] Hint: Tc<2dt may require smaller dt Runoff = 6.46 cfs @ 12.11 hrs, Volume= 13,003 cf, Depth= 3.03" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.05 hrs MSE 24-hr 3 10-Year Rainfall=4.22" Area (sf) CN Description 16,000 98 Building 24,500 98 Paving 10,993 56 INPUT PER WATERSHED 51,493 89 Weighted Average 10,993 21.35% Pervious Area 40,500 78.65% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 1.7 100 0.0100 0.98 Sheet Flow, Roof Smooth surfaces n= 0.011 P2= 2.80" 1.3 100 0.0200 1.29 Sheet Flow, Parking Smooth surfaces n= 0.011 P2= 2.80" 1.6 462 0.0050 4.84 5.94 Pipe Channel, 15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31' n= 0.010 Concrete pipe, straight & clean 4.6 662 Total Siegfried 10-20-23 MSE 24-hr 3 10-Year Rainfall=4.22" Prepared by LG Printed 10/20/2023 HydroCAD® 10.00-26 s/n 07614 ©2020 HydroCAD Software Solutions LLC Page 17 Subcatchment 2S: Proposed Draining to Infiltration Basin Hydroraph 7 Runoff 6.46 cfs [ MSE 24-hr 3 6- 10-Year Rainfall=4.22" I � II I Runoff Area=51,493 sf 5 Runoff Volume=13,003 cf 12 4 Runoff Depth=3.03 . LL i Flow Length=662' 3 Tc=4.6 m i n T 10 2 CN=89 - I 0 1 2 3 4 5,..6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours) Siegfried 10-20-23 MSE 24-hr 3 10-Year Rainfall=4.22" Prepared by LG Printed 10/20/2023 HydroCAD® 10.00-26 s/n 07614 ©2020 HydroCAD Software Solutions LLC Page 18 Summary for Subcatchment 3S: Proposed Green Space NOT Draining to BMP's [49] Hint: Tc<2dt may require smaller dt Runoff = 0.28 cfs @ 12.14 hrs, Volume= 657 cf, Depth= 0.67" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.05 hrs MSE 24-hr 3 10-Year Rainfall=4.22" Area (sf) CN Description 11,800 56 INPUT PER WATERSHED 11,800 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 1.7 100 0.0100 0.98 Sheet Flow, Roof Smooth surfaces n= 0.011 P2= 2.80" 1.3 100 0.0200 1.29 Sheet Flow, Parking Smooth surfaces n= 0.011 P2= 2.80" 1.6 462 0.0050 4.84 5.94 Pipe Channel, 15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31' n= 0.010 Concrete pipe, straight & clean 4.6 662 Total Subcatchment 3S: Proposed Green Space NOT Draining to BMP's Hydrograph 0.3 D Runoff 0.28 cfs 0.28= MSE X24-hr-3- 0.26 0.24- - , 10-Yea'r Rainfall=4.22" 0.22. 0.2W Runoff Area=11 ,800 sf 0.18 Runoff Volume=657 cf 0.16-: Runoff-Depth=0:67" 2 0.14 0.12 How-Length=662. 0.1 Tc=4.6 tai-r -- 0.08= �� ' -56 0.06 V . 0.04 0.02. /777 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours) Siegfried 10-20-23 MSE 24-hr 3 10-Year Rainfall=4.22" Prepared by LG Printed 10/20/2023 HydroCAD® 10.00-26 s/n 07614 ©2020 HydroCAD Software Solutions LLC Page 19 Summary for Pond 1P: Underground TDA Storage Inflow Area = 51,493 sf, 78.65%Impervious, Inflow Depth = 3.03" for 10-Year event Inflow = 6.46 cfs @ 12.11 hrs, Volume= 13,003 cf Outflow = 0.27 cfs @ 13.50 hrs, Volume= 8,503 cf, Atten= 96°/4 Lag= 83.4 min Discarded = 0.10 cfs @ 13.50 hrs, Volume= 6,891 cf Primary = 0.17 cfs @ 13.50 hrs, Volume= 1,612 cf Routing by Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.05 hrs Peak Elev= 776.05'@ 13.50 hrs Surf.Area= 9,625 sf Storage= 8,656 cf Plug-Flow detention time=418.7 min calculated for 8,503 cf(65% of inflow) Center-of-Mass det. time=346.3 min ( 1,129.5 - 783.2 ) Volume Invert Avail.Storage Storage Description #1 774.00' 25,429 cf Custom Stage Data (Prismatid.)isted below(Recalc) 50,858 cf Overall x 50.0% Voids Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 774.00 7,245 0 0 775.00 8,394 7,820 7,820 776.00 9,561 8,978 16,797 777.00 10,746 10,154 26,951 778.00 11,949 11,348 38,298 779.00 13,170 12,560 50,858 Device Routing Invert Outlet Devices #1 Device 3 775.80' 6.0" Vert. Orifice/Grate C= 0.600 #2 Discarded 774.00' 0.450 in/hr Exfiltration over Surface area #3 Primary 775.00' 12.0" Round Culvert L= 100.0' CMP, projecting, no headwall, Ke=0.900 Inlet/Outlet Invert=775.00'/774.00' S= 0.0100'/' Cc= 0.900 n= 0.010 PVC, smooth interior, Flow Area=0.79 sf #4 Device 3 777.50' 12.0" Vert. Orifice/Grate C= 0.600 Discarded OutFlowMax=0.10 cfs@ 13.50 hrs HW=776.05' (Free Discharge) L2=Exfiltration(Exfiltration Controls 0.10 cfs) Primary OutFlowMax=0.17 cfs@ 13.50 hrs HW=776.05' (Free Discharge) Z3=Culvert(Passes 0.17 cfs of 2.22 cfs potential flow) t41=Orifice/Grate(Orifice Controls 0.17 cfs @ 1.71 fps) =Orifice/Grate( Controls 0.00 cfs) • Siegfried 10-20-23 MSE 24-hr 3 10-Year Rainfall=4.22" Prepared by LG Printed 10/20/2023 HydroCAD® 10.00-26 s/n 07614 ©2020 HydroCAD Software Solutions LLC Page 20 Pond 1P: Underground TDA Storage Hydrogrsps£ 6 46 cfs ' r Inflow i Outflow I Discarded Inflow Area=51493 sf rE Primary / Peak Elev=776.05' Storage=8,656 cf 5 o 4 4 3 0 LL 3 CO 2 114 :;',;;:-/-474. .:47" r { ".:*:;',-,.-•' ‹, 0 27 cfs r ."'".'/..-4: ,r ,4 z, 1 '''-':''''''4'/'' r r:- l r'f" aI r • • ,-0.4%.,-4.4:',--24-7-'" r` s ✓., r' r � b�: � 0.17 cfS < ?c�,"�" «� ax , , j' '., o a � . r e ,` s ;t'/r`.r!,�f,//i''',�1'f�'',/'fd`''/r`.�'/'l 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours) Siegfried 10-20-23 MSE 24-hr 3 10-Year Rainfall=4.22" Prepared by LG Printed 10/20/2023 HydroCAD® 10.00-26 s/n 07614 ©2020 HydroCAD Software Solutions LLC Page 21 Summary for Link 3L: Combined Proposed Inflow Area = 63,293 sf, 63.99%Impervious, Inflow Depth = 0.43" for 10-Year event Inflow = 0.28 cfs @ 12.14 hrs, Volume= 2,269 cf Primary = 0.28 cfs @ 12.14 hrs, Volume= 2,269 cf, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-30.00 hrs, dt= 0.05 hrs Link 3L: Combined Proposed Hydrograph i °" Inflow 0.28 cfs C1 Primary 3 0. 0.28 cfs � 00 3_ ,, Inflow Area=63,293' sf 0.26 0.24 II 0.22 0.2- To-- 0.18 0.16- 0.14. 0.12- 01_ 0.08-- 0.06' 0.04 - 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours) Siegfried 10-20-23 MSE 24-hr 3 100-Year Rainfall=7.41" Prepared by LG Printed 10/20/2023 HydroCAD® 10.00-26 s/n 07614 ©2020 HydroCAD Software Solutions LLC Page 22 Time span=0.00-30.00 hrs, dt=0.05 hrs, 601 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method SubcatchmentlS: Existing Runoff Area=63,293 sf 0.00% Impervious Runoff Depth=2.49" Flow Length=354' Tc=13.0 min CN=56 Runoff=4.83 cfs 13,128 cf Subcatchmenl2S: ProposedDrainingto Runoff Area=51,493 sf 78.65% Impervious Runoff Depth=6.11" Flow Length=662' Tc=4.6 min CN=89 Runoff=12.46 cfs 26,213 cf Subcatchment3S: ProposedGreenSpace NOT Runoff Area=11,800 sf 0.00% Impervious Runoff Depth=2.49" Flow Length=662' Tc=4.6 min CN=56 Runoff=1.25 cfs 2,448 cf Pond 1P: UndergroundTDAStorage Peak Elev=777.33' Storage=15,295 cf Inflow=12.46 cfs 26,213 cf Discarded=0.12 cfs 7,768 cf Primary=1.07 cfs 13,249 cf Outflow=1.19 cfs 21,017 cf Link 3L:CombinedProposed Inflow=1.92 cfs 15,697 cf Primary=1.92 cfs 15,697 cf Total Runoff Area = 126,586 sf Runoff Volume = 41,789 cf Average Runoff Depth = 3.96" 68.01% Pervious = 86,086 sf 31.99% Impervious = 40,500 sf Siegfried 10-20-23 MSE 24-hr 3 100-Year Rainfall=7.41" Prepared by LG Printed 10/20/2023 HydroCAD® 10.00-26 s/n 07614 ©2020 HydroCAD Software Solutions LLC Page 23 Summary for Subcatchment 1S: Existing Runoff = 4.83 cfs@ 12.22 hrs, Volume= 13,128 cf, Depth= 2.49" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.05 hrs MSE 24-hr 3 100-Year Rainfall=7.41" Area (sf) CN Description 63,293 56 INPUT PER WATERSHED 63,293 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 11.6 50 0.0100 0.07 Sheet Flow, Sheet Flow Grass: Dense n= 0.240 P2= 2.80" 1.4 304 0.0500 3.60 Shallow Concentrated Flow, Shallow Concentrated Flow Unpaved Kv= 16.1 fps 13.0 354 Total Subcatchment 1S: Existing Hydrograph rapph Runoff 5.. 4.83 cfs MSE 24-hr 3 100-Year Rainfall=7 4-1"-'-- 4 Runoff Area=63,293 sf Runoff Volume=13,128 cf 72 3 Runoff Depth=2.49" ;Flow Length=354' 2 QTc=i 3.0 min CN=56 1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours) Siegfried 10-20-23 MSE 24-hr 3 100-Year Rainfall=7.41" Prepared by LG Printed 10/20/2023 HydroCAD® 10.00-26 sin 07614 ©2020 HydroCAD Software Solutions LLC Page 24 Summary for Subcatchment 2S: Proposed Draining to Infiltration Basin [49] Hint: Tc<2dt may require smaller dt Runoff = 12.46 cfs @ 12.11 hrs, Volume= 26,213 cf, Depth= 6.11" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.05 hrs MSE 24-hr 3 100-Year Rainfall=7.41" Area (sf) CN Description 16,000 98 Building 24,500 98 Paving 10,993 56 INPUT PER WATERSHED 51,493 89 Weighted Average 10,993 21.35% Pervious Area 40,500 78.65% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 1.7 100 0.0100 0.98 Sheet Flow, Roof Smooth surfaces n= 0.011 P2= 2.80" 1.3 100 0.0200 1.29 Sheet Flow, Parking Smooth surfaces n= 0.011 P2= 2.80" 1.6 462 0.0050 4.84 5.94 Pipe Channel, 15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31' n= 0.010 Concrete pipe, straight & clean 4.6 662 Total Siegfried 10-20-23 MSE 24-hr 3 100-Year Rainfall=7.41" Prepared by LG Printed 10/20/2023 HydroCAD® 10.00-26 s/n 07614 ©2020 HydroCAD Software Solutions LLC Page 25 Subcatchment 2S: Proposed Draining to Infiltration Basin Hydrograph I I j 1 Runoff 13- 12.46 cfs 1 , I 1 1 12- J MSE 24.hr 3 10q Year;Rl „- � I 1 - 1 ainfall=x.41" iE•' 1 ,o-? 1 Runoff Area=51:,493 sf 9: 1 I1 _RLInoff�VolUme-=26213 of- Runoff-Dept-h=6.-117-- 0 7 ) ; - Iflow Length=662' 1 - LL 6 T T -f-- 1 1 I I Tc=4.6 M i n 5 _____ i 1 I J 1 I 1 1__ 4� CN-69 ' 3-- 1 jv° 1 I I I I I I I T 1 -- 7 V - I--r-1----i F - 1 -r-1- 2 I YL F' 1 . � I dlowxworor 1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours) Siegfried 10-20-23 MSE 24-hr 3 100-Year Rainfall=7.41" Prepared by LG Printed 10/20/2023 HydroCAD® 10.00-26 s/n 07614 ©2020 HydroCAD Software Solutions LLC Page 26 Summary for Subcatchment 3S: Proposed Green Space NOT Draining to BMP's [49] Hint: Tc<2dt may require smaller dt Runoff = 1.25 cfs @ 12.12 hrs, Volume= 2,448 cf, Depth= 2.49" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.05 hrs MSE 24-hr 3 100-Year Rainfall=7.41" Area (sf) CN Description 11,800 56 INPUT PER WATERSHED 11,800 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 1.7 100 0.0100 0.98 Sheet Flow, Roof Smooth surfaces n= 0.011 P2= 2.80" 1.3 100 0.0200 1.29 Sheet Flow, Parking Smooth surfaces n= 0.011 P2= 2.80" 1.6 462 0.0050 4.84 5.94 Pipe Channel, 15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31' n= 0.010 Concrete pipe, straight & clean 4.6 662 Total Subcatchment 3S: Proposed Green Space NOT Draining to BMP's Hydrograph J Runoff 1.25 cfs ' MSE 24-hr 3 100-Year Rainfall=7.41" II Runoff Area--11,800 sf 11 Runoff Volume=2,448 cf 3 , Runoff Depth-2.49`' Flow Length=662' Tc=4.6 m i n CN=56 or 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours) Siegfried 10-20-23 MSE 24-hr 3 100-Year Rainfall=7.41" Prepared by LG Printed 10/20/2023 HydroCAD® 10.00-26 s/n 07614 ©2020 HydroCAD Software Solutions LLC Page 27 Summary for Pond 1P: Underground TDA Storage Inflow Area = 51,493 sf, 78.65% Impervious, Inflow Depth = 6.11" for 100-Year event Inflow = 12.46 cfs @ 12.11 hrs, Volume= 26,213 cf Outflow = 1.19 cfs @ 12.61 hrs, Volume= 21,017 cf, Atten= 90°/4 Lag= 29.9 min Discarded = 0.12 cfs @ 12.61 hrs, Volume= 7,768 cf Primary = 1.07 cfs @ 12.61 hrs, Volume= 13,249 cf Routing by Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.05 hrs Peak Elev= 777.33'@ 12.61 hrs Surf.Area= 11,146 sf Storage= 15,295 cf Plug-Flow detention time=248.0 min calculated for 21,017 cf(80% of inflow) Center-of-Mass det. time=189.4 min ( 958.9 - 769.5 ) Volume Invert Avail.Storage Storage Description #1 774.00' 25,429 cf Custom Stage Data (Prismatid)isted below(Recalc) 50,858 cf Overall x 50.0% Voids Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 774.00 7,245 0 0 775.00 8,394 7,820 7,820 776.00 9,561 8,978 16,797 777.00 10,746 10,154 26,951 778.00 11,949 11,348 38,298 779.00 13,170 12,560 50,858 Device Routing Invert Outlet Devices #1 Device 3 775.80' 6.0" Vert. Orifice/Grate C= 0.600 #2 Discarded 774.00' 0.450 in/hr Exfiltration over Surface area #3 Primary 775.00' 12.0" Round Culvert L= 100.0' CMP, projecting, no headwall, Ke= 0.900 Inlet/Outlet Invert= 775.00'/774.00' S= 0.0100'/' Cc= 0.900 n= 0.010 PVC, smooth interior, Flow Area=0.79 sf 1#'1 Device 3 777.50' 12.0" Vert. Orifice/Grate C= 0.600 Discarded OutFlowMax=0.12 cfs© 12.61 hrs HW=777.33' (Free Discharge) t2=Exfiltration (Exfiltration Controls 0.12 cfs) Primary OutFlowMax=1.07 cfs @ 12.61 hrs HW=777.33' (Free Discharge) tom=Culvert (Passes 1.07 cfs of 4.04 cfs potential flow) -1=Orifice/Grate(Orifice Controls 1.07 cfs © 5.45 fps) -4=Orifice/Grate( Controls 0.00 cfs) Siegfried 10-20-23 MSE 24-hr 3 100-Year Rainfall=7.41" Prepared by LG Printed 10/20/2023 HydroCAD® 10.00-26 s/n 07614 ©2020 HydroCAD Software Solutions LLC Page 28 Pond 1P: Underground TDA Storage Hyd o raph 12 46 cfs I Inflow �.. _ /� 1 Outflow Inflow Area=51,493 sf Pr maryed 13- __ _._1_ _.J L Peak Etev=777 33L- Storage= 11. I I I I I I 16,295- cf-. L L L 1 1 1 1 1 J __I _._L-L-L - I I I I I I I I I I I I. - ! I j I I I ! LL 6 1 L J. J I,- _L_ I T r 4- -- _i 3_ 1.19 cfs /00„,2:0-0e- , , 1 07 cfs 1.0 ., 1/"6/. 0ff'97Zii b/ �i�f1.////l/%iG%' 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours) Siegfried 10-20-23 MSE 24-hr 3 100-Year Rainfall=7.41" Prepared by LG Printed 10/20/2023 HydroCAD® 10.00-26 s/n 07614 ©2020 HydroCAD Software Solutions LLC Page 29 Summary for Link 3L: Combined Proposed Inflow Area = 63,293 sf, 63.99%Impervious, Inflow Depth = 2.98" for 100-Year event Inflow = 1.92 cfs @ 12.14 hrs, Volume= 15,697 cf Primary = 1.92 cfs @ 12.14 hrs, Volume= 15,697 cf, Atten= 0°/q Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-30.00 hrs, dt= 0.05 hrs Link 3L: Combined Proposed Hydrograph E Inflow 1.92 cfs 0 Primary 2 1192cfs Inflow Area=63,293 sf 91 -A 1 ###;;#: o / / ,f 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Time (hours) AliPhase Companies, incorporated 404-A St. Croix Trail North, Lakeland, MN 55043 Phone: 651-436-2930 FAX: 651-436-3918 allphasecompanies@gmail.com May 15, 2023 Tim Siegfried George Siegfried Construction Co. 510 Perro Creek Dr. Bayport, MN 55003 tim@siegfriedconstruction.com RE: Geotechnical Evaluation Property: 5416 Stagecoach Trail N. Oak Park Heights, MN 55082 AllPhase # PEC #6111 Dear Mr.Siegfried: This report concerns our review of soil conditions throughout a site of proposed building construction at 5416 Stagecoach Trail N., Qak Park Heights. A large office and commercial building will be constructed on the property shortly. We were requested to evaluate the soil conditions throughout the property for foundation construction and for water percolation/infiltration of site drainage. On April 27, 2023, we excavated seven test pits at the property. Four test pits were excavated at the outside corners of the proposed structure and three test pits were excavated at and near infiltration areas on the property. The soil profiles for the test pits are shown on the attached sheets. In general, less than 1' of granular topsoil was found at each test location. Below the topsoil, we found granular mineral soil extending down to the bottom of each pit. The test pits in the building area encountered soil materials which could support footing loadings of 3000 psf, with a factor of safety of 3 against shear failure and with very little floor or footing building settlement. One of the test pits encountered 5of old fill material for a former house footprinl where most of the demolition debris had apparently been removed from the site. In other areas in the north portion of the proposed building, extensive fill material will be required in order to establish the proposed finished floor elevation of the structure. For instance, the staking at the property indicated 14.5' of fill material will be necessary in the northwest Page 1 of 2 PEC 116111 corner region to establish the proposed finished grades. This will also require extensive filling beyond the building area to establish a stable structural fill system. However, placement of successive 12" layers of earth material and compaction to at least 100%of a standard proctor (ASTM D-698) will result in a soil system which can support moderate (150 psf) floor loadings. Some soil stabilization methods will likely be required in the mass placement. In the infiltration areas where the other three test pits were excavated, we found mineral soils beneath the topsoil which had excellent infiltration qualities with likely infiltration rates comparable to clean, coarse sand materials. These soils will accommodate drainage comparable to published upper level percolation rates for excellent mound systems. We acknowledge that you have designed excellent underground TDA systems and those systems have been sized for the property. If additional investigation is desired, please contact us at 651-436-2930 . Respectfully, Professional Engineering Consultants, Inc. I hereby certify that this plan, specification, or report was prepared by me or under my Brian R. Dobie, P.E. direct supervision and that I am a duly President Registered Professional Engineer under the laws of the State of Minnesota. //j - /7-2 Brian R. Dobie, P.E. (- Date -5- - 21' Reg. No. 9798 ctik Rennie Smith Date Senior Project Manager Page 2 of 2 x 73- , ... , , 7-----7-----7- 7 , „q, . 1.1 t if t 1 `�--'� 777 { /''� 4 fl "`� -""`-77g „✓`/' 7g0./" ', ''''''''-:7----"""""-------.--"'-. 11;:r.7 a 0,7- i , 78 , ISUMP 7?!?,C 1 i i IF a I a i 5rilecoach... n4 At: 1 / _ UNDERGROUND�y +.7SYSTEM re 0 14— Pi it.TOA 1. 1r'i OT OM 77? =778.0 .. i OP I ,e,..-------* 'er LOA*`+ 0.0405 i ti 1 / t �,,,D oq 7`33^ '' _ ;' i£°s �y,ass .il---------.._._-- i # - t '- - - 1 -',,, 4-4(1,,,,N.:).2,,, ,,,, f.z..N a.oc ! : L.,,,,,*,,.. f �___ SIE , AV ei ,, _ .� CONNECI 1:ON r „\cot- A .,_,..............____„p • NEW W4T'R COPiNECTTO ii' ' f'P�SO LINE OR SEPARATE FIRE?! t_ • I 765 __.. %` 6 °'��, Q _ r_5� ''' '..4"'"":-.7;.7:r769 1 768----'- 769 "`-- X77 "".-.� I , 770 77i 77._____- --7r3 77A77�"�--- �n0 7• 7i— _ ell• 773 ___- ',,----'_"774 5_ _ ,--- 776--" 8 7 of h� 1 � �r titI . �‘ /// a i . Yt- (7, ; PROPOSED BLDGL/4FFE=783 . `• i'N1./=?Ic^.87----' i ,r I f 1 . ) 44, . 1 t a I. J {' I , .__ - g d y t1 i i 1 A.2)I \ ie''' nji _ pa<4rI i r.1... :• - At A' 6 PL. ti e Y", G.t$. b c.,9 . o 3�1' i �Ll� tV �l_+t c T jr� S" 0fLOa f cb J3' ,SUMP`7!fit:,0! 782--_ LOG OF SOIL TEST PIT# 1 Project� 5416 Stagecoach TdN, Oak Park Hekzhts' K4N ' Depth Soil Identification Geology N(BPF) Water Sample Recovery Field ' | | Notes/Tests Topsoil Topsoil - ~~----` Silty Sand (SM) 1- 81'� 2' Silty Sand, and 4"gravel, Glacial reddish bro�n,deno� , �' Outwash -- moist -- (SP-S&1) 4' 5; -G' ki _7 _ ~* ,8 9�� -^^��� _ ' � g —, ' .�u Endof Pit 0 -- / -- ! LOG OF SOn.TEST PT# 2 Project: 54l6 Stagecoach Td N. Oak Park Heights, MN Depth Soil Identification Geology k(RPF) Water Sample Recovery Field | | Notes/Tests Topsoil Topsoil | | R, Silty nd (SM) 1' FillmatehaLdarkRrey�hIQ" Old Fill 2' brown,silty sand, some Material 3' 3' 4' , GihySand and graveL _- reddish browndense, ' 6}ada| DOW N,1 moist`��) 6' —` Outwash — End of Pit 7' t ST,E,...1,?tiEt..i41 ya //e" kiv - 9' LOG OF SOIL TEST P[r# 3 Project: ---- -- --- ----- -- | 54l63hagec000hTdN. Oak Park Heights, MN Depth Soil Identification Geology N(BPF) Water Sample Recovery ' Field Notes/Tests Topsoil Topsoil Silty Sand (SM) Silty 5am��� aN1� Glacial 2' 0ra»eL /edd�hbrown -- Outwash fine tomedium 8mined, . -- 3 , dense, moist 6' 61/�`- -^ ,__ . *� °�� ='c9 --"-^ - EndofPi _ 8' '` ia 9' -- ' LOG OF SOIL TEST PITh 4 Project: 54l6 ,e�oochTdN, DokPm� H�ighb^ ��N --- -- - | ` ---'-- - } Depth Soil Identification Geology N(BPF) Water Samplel SampleRecovery | Field Notes/Tests Topsoil Topsoil . ^ 6" Silty Sand (SK4) Silty Sand, brown' -- Glacial 2' 0negmined, nograveL -- reddish browndense Outwash ^ moist(SP- K4) 4' Silty Sandreddish brown 5' a little gravel,dense, moist(SM) 6' 7' nittogIsioNALI -- End of / 17,1// - _ � - �, ,°°' / 44 -- - - — ' LOG OF SOIL TEST PIT# 5 Project: | 54l6 Stagecoach Tn N. Oak Park Heights. MN --'---- - - Depth Soil Identification Geology N(BPF) Water Sample Recvery o -� Field Notes/Tests Topsoil �- Topsoil T----- - - ' 4" , Silty Sand 1' Silty Sand, reddish brown -2' mostly fine grained, no gravel, dense, moist -- , (SP-SM) ' 4, 4-1/21 *End *EndofP|t ao iso -- *Note'at bottom of Pit v-• � encountered extensive \ heavy gravel '� 9798 ‘'‘,',4ror .'�`^ �`.. -- { LOG OF SOft TEST PIP! 6 Project: '5416ecooc . Heights, /�N ----- -- - -- -_-_� Depth Soil Identification Geology N(BPF) Water~-�Sample / Recovery 1 Field Notes/Tests Topsoil Topsoil O" Silty ' -'---- -------- ------ � ' ' | Silty 5and,vv�ha |btle -- Glacial / | 2' gravel, reddish brown, Outwash dense, moist -- , (SP-SM) _ 5/ - 6' _ 7' Wit tit End ofP� —" % 3/4 .*^ " -- | LOG OF SOIL TEST P1T# 7 Project. [�416 -h TdN, OokPark-----Heights,--' MN -- - ----- ---- ` Depth Soil Identification Geology N(BPF) Water Sample ! Recovery Field| � Notes/Tests Topsoil Topsoil / ---� O" GkySand (SK4) l ' Silty San¢ md reddish -- Glacial 2' mostly fine with Outwash little gravel, dense,moist - ~ (SP-SM) 4' - 5' - 6' OtAf otiot &' - / End of Pit ~ ' of 61)11% -- | .• 1 GiAggificAn.Q.ELSIFA_Qa§ ' II i ''.. 1• . [NE• "k 1 ASTRii Dotignation: 0 2487 -66 T AND 0 2466-66 T Unified Soil Classification System,. — — Group Major divisions Typical names Laboratory clacification entrant, symbols -- 1 — — — -i Well-graded gravels,gravel-sand -*a I D60 (1,30) GAI mixtures,little or no fines ,..°?-: Cu--,--_greater than 4,Cc- -between 1 and 3 Dip Di0X060 o L• 73 'cli cU o, -- --------- ----- .8 H ,iv C 0 t oi ... GP Poorly graded gravels, gravel- o • :::: 3 Not meeting all gradation requirements for GW --)i sand mixtures,little or no fines . g ,, .... • Qs --- ai (0 to 3? d a :L-ii g mixtures Silty gravels, gravel-sand-silt -:.,-L,' Attebelow rberg limits "A" n v)V1 ci c;g. c,:6:,..5 „., line or P.I,less than 4 .. 1 2 - c .-- u C.0 M at 0 Above "A" line with P.I.. g ..... a 6 3.S 2 1g sg between 4 end 7 era dor- . der I ine cases requiring UES c1 GC Clayey gravels,gravel-sand-clay ',7-I = Atterberg limits above"A" of dual symbols cI ' ' * 8 mixtures '''',. ' ' line with P.1,greater than 7 I _______ _____—__i E •35 ... _ , 'S°Vi t 1-4 7 Well-gradad sands,gravelly 1; ,,S ; : : 06o ID 3012 3 m.,t1 c SW 'c . , . ' cu---greater than 6;Cc- between 1 and 3 76 c •v.1: sands,little or no fines e % • . • DIO DioX.D60 ".7. 2. 7,-, c o V., N-N ! c _____ -a- . . . 1._. . ? .:_- 4,, g 8 • • • Poorly gradedsands, gravelly 7 z.. .. - : : : Not meeting all gradation requirements far SW 1:i '`i .t. sande,little or no fines 5"6 i . • - o - • .c 4 ic; -5 §= •'E ' - c =iz v. o •,•• 1:3 • re §i - 8 ? d vc 6 r. .... -...'3 .- em C. 1 Atterberg limits below"A" tt" k z;c6 a,ev l , or an c ,_ c g Sim Silty sands, sand-silt mic. xtures 'eline P.1.less th4 Limits plotting in hatched z.-- ..e= to- u „,.; c- aoEc % k I zone with P.I. between 4 P i- and 7 are borderlin . e mast - - .i.i?. ..,0.p.,-... vi ?. 60 requiring use of duel eym- - Clayey sands, sand-clay mix- ,. n9 ,L, a; a — Atterterg limits above"A" bols. a SC tures -1 2 in line with P.I.greater than 7 --- Inorganic silts and very fine • sanis.rock f le,ur,silty or cloy- I g ML ay fine sands or clayey silts 60 c with slight plasticity I in 2 3-S --- --. For classification of fine-grained re Inorganic clays of low to me- soils end fine fraction of coarse- _ .t Ti p -a 4 CL diem plasticity,gravelly days, 13 5grained soils. sandy clays, silty clays, lean Atterberg Limits plotting in 8 4-E clays hatched arta are borderline ciassi- /H ri A 13 ficetions requiring use of dual 6 -5 2 o- 410_symbols. OL Organic silts and organic silty x Equation of Aline: re _ clays of low plasticity i PI=0.73 ILL-20l ..-, .4 k- 1 1 3-. MH Inorganic silts, micaceous or ..7., diatomaceous fine sandy or :5///OH sort PAH T6 l'-' i silty soils,elastic silts CZ ..i" / r 1 .9 3 1- ____ ___ 20 o 0 Inorganic clays of high plas- CL CH ticity,fat clays 10 — Ts c CL-M \W g i25-ts 4........,...... .‘..r. Rill.and Of_ [ & Organic clays of medium to g i••• OH .-' — - ----. high plasticity,organic silts o— - ..... 0 10 20 30 40 50 60 70 20 ht 114 Liquid Limit in Peat and other highly organic Pimicity Chart Vg Pt soils i 0 , . , „