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Report , l k pcoci - (cc, i C ; 12562 SW MAIN STREET FINAL STORIVIWATER REPORT DATE: MAY, 2009 CLIENT: TWO G's REAL ESTATE, LLC. 18395 WOOD THRUSH STREET LAKE OSWEGO, OR 97035 ENGINEERING CONTACT: ALEXANDER HURLEY ENGINEERING FIRM: AKS ENGINEERING & FORESTRY i 4Y.L.Y. ._ .:::. 5 G . .„, . „..,,, >Fo Vl? ' ,.,„,„ ENGINEERING & FORESTRY 13910 SW GALBREATH DRIVE, SUITE 100 SHERWOOD, OR 97140 PHONE: (503) 925 -8799 FAX: (503) 925 -8969 5 , v J 8 -O7 L c. CREGON 7';. \ -7^ ,1 _ ` ,,, ' )RENEWAL DATE: 4C3 -17 1 C Ir ZL -- Ocx) g, REGEIVE JUN 0 3 2009 CITY Cr: TIGARD BUILDING DWISJON 12562 SW MAIN STREET FINAL STORMWATER REPORT DATE: MAY, 2009 CLIENT: TWO G's REAL ESTATE, LLC. 18395 WOOD THRUSH STREET LAKE OSWEGO, OR 97035 ENGINEERING CONTACT: ALEXANDER HURLEY ENGINEERING FIRM: AKS ENGINEERING & FORESTRY K ,„,„ ENGINEERING & FORESTRY 13910 SW GALBREATH DRIVE, SUITE 100 SHERWOOD, OR 97140 PHONE: (503) 925 -8799 FAX: (503) 925 -8969 SITS- t n City of Tigard A• roved Plans_� D By- �►'r<. Date ) O z5�— kip OFFICE COPY TABLE OF CONTENTS 1.0 PURPOSE OF REPORT 2.0 PROJECT LOCATION /DESCRIPTION 3.0 REGULATORY DESIGN CRITERIA 3.1 STORMWATER QUANTITY MANAGEMENT CRITERIA 3.2 STORMWATER QUALITY MANAGEMENT CRITERIA 4.0 DESIGN METHODOLOGY 5.0 DESIGN PARAMETERS 5.1 DESIGN STORM 5.1.1 ON -SITE INLET AND CONDUIT SIZING 5.2 PRE - DEVELOPED SITE TOPOGRAPHY AND LAND USE 5.2.1 SITE TOPOGRAPHY 5.2.2 LAND USE 5.3 SOIL TYPE 5.4 POST - DEVELOPED SITE TOPOGRAPHY AND LAND USE 5.4.1 SITE TOPOGRAPHY 5.4.2 LAND USE 5.4.3 POST - DEVELOPED INPUT PARAMETERS 5.5 DESCRIPTION OF OFF -SITE CONTRIBUTORY BASINS 6.0 CALCULATION METHODOLOGY 6.1 PROPOSED STORMWATER CONDUIT SIZING AND INLET SPACING 6.2 PROPOSED STORMWATER QUALITY CONTROL FACILITY DESIGN 6.3 PROPOSED STORMWATER QUANTITY CONTROL FACILITY DESIGN 6.4 ENERGY DISSIPATER CALCULATIONS 6.5 DOWNSTREAM ANALYSIS APPENDIX 1 -1 VICINITY MAP APPENDIX 1 -2 CATCHMENT MAP APPENDIX 2 -1 25 -YEAR STORM EVENT (3.90 ") - HYDROGRAPH AND FLOW INFORMATION APPENDIX 2 -2 100 -YEAR STORM EVENT (4.50 ") - HYDROGRAPH AND FLOW INFORMATION APPENDIX 3 -1 WATER QUALITY CALCULATIONS APPENDIX 4 -1 RELEVANT INFORMATION FROM CLEAN WATER SERVICES DESIGN AND CONSTRUCTION STANDARDS MANUAL FOR SANITARY SEWER AND SURFACE WATER MANAGEMENT (R &O 04 -9) FINAL STORMWATER REPORT PROJECT 12562 SW MAIN STREET 1.0 PURPOSE OF REPORT The purpose of this report is to document the criteria for which the stormwater system for this site was designed to meet, the sources of information on which the analysis is based, the design methodology, and the results of the analysis. 2.0 PROJECT LOCATION /DESCRIPTION The proposed development is on a parcel of land (approximately 24,864 SF) in Section 2, Township 2 South, Range 1 West, Willamette Meridian, City of Tigard, Washington County, Oregon (Tax Lot 1101). The project site is located at 12562 SW Main Street, Tigard, Oregon. The proposed development activity includes stormwater drainage improvements and a water quality facility to convey and treat surface water runoff from existing concrete pavers in the parking area behind the building. 3.0 REGULATORY DESIGN CRITERIA 3.1 STORMWATER QUANTITY MANAGEMENT CRITERIA The City of Tigard utilizes Clean Water Services (CWS) Design and Construction Standards for Sanitary Sewer and Surface Water Management (R &O 07 -20) to address stormwater quantity management criteria. This manual requires stormwater quantity management if capacity issues are identified in the downstream conveyance system. Per City of Tigard staff, neither stormwater detention or a downstream analysis is required for this project. 3.2 STORMWATER QUALITY MANAGEMENT CRITERIA The City of Tigard utilizes Clean Water Services (CWS) Design and Construction Standards for Sanitary Sewer and Surface Water Management (R &O 07 -20) to address stormwater quality management criteria. Table 4 -1 of the design manual specifies impervious areas requiring treatment on redevelopment sites. There is 10,161 SF (0.23 acres) of existing impervious area on site (excluding the concrete pavers), none of which will be disturbed; therefore, no new treatment is required for the existing impervious area. Stormwater treatment for runoff from the concrete pavers is required. 4.0 DESIGN METHODOLOGY The Santa Barbara Urban Hydrograph (SBUH) Method was used to model stormwater runoff and design the stormwater facility. This method utilizes the SCS Type 1 A 24 -hour storm. Hydrocad computer software aided in the analysis. 5.0 DESIGN PARAMETERS 5.1 DESIGN STORM 5.1.1 ON -SITE INLET AND CONDUIT SIZING Stormwater inlets for the site are placed at locations that will adequately control stormwater runoff from the recently installed concrete pavers. The stormwater pipes have been sized by using Manning's equation based on peak flows for the 25 -year storm event. 5.2 PRE- DEVELOPED SITE TOPOGRAPHY AND LAND USE 5.2.1 SITE TOPOGRAPHY The western portion of the project site has moderate slopes of less than 2% sloping east towards Fanno Creek. The eastern portion of the site consists of steep slopes associated with Fanno Creek. 5.2.2 LAND USE The existing land use is an eating and drinking establishment (Max's Fanno Creek Brew Pub). 5.3 SOIL TYPE The soil for the site is classified as McBee silt loam (hydrologic group "C ") according to the USDA Soil Survey for Washington County, Oregon 5.4 POST - DEVELOPED SITE TOPOGRAPHY AND LAND USE 5.4.1 SITE TOPOGRAPHY The existing parking area behind the building was recently improved with concrete pavers. Post - developed site topography matches the pre- developed site topography. 5.4.2 LAND USE The site will continue to be used as an eating and drinking establishment (Max's Fanno Creek Brew Pub). 5.4.3 POST- DEVELOPED INPUT PARAMETERS See HydroCAD Analysis and Water Quality Calculations' (Appendices 2 -1, 2 -2, and 3 -1). 5.5 DESCRIPTION OF OFF -SITE CONTRIBUTORY BASINS There are no off -site contributory basins. The site is bordered to the east and south by the Fanno Creek drainage way; SW Main Street to the north; and a developed commercial site to the west. SW Main Street and the abutting commercial site include conveyance systems to control stormwater nmoff. 6.0 CALCULATION METHODOLOGY 6.1 PROPOSED STORMWATER CONDUIT SIZING AND INLET SPACING The stormwater pipes have been sized by using Manning's equation based on peak flows for the 25 -year storm event (see Appendix 2 -1). 6.2 PROPOSED STORMWATER QUALITY CONTROL FACILITY DESIGN Stormwater runoff from the concrete pavers will be routed to a privately owned and maintained extended dry basin for treatment prior to being discharged into the on -site portion of Fanno Creek. The basin has been sized to meet Clean Water Services requirements. 6.3 PROPOSED STORMWATER QUANTITY CONTROL FACILTY DESIGN Per City ,of Tigard staff, stormwater quantity control is not required. 6.4 ENERGY DISSIPATER Rip -rap energy dissipaters are located at the pond inlet and pond discharge point in accordance with Clean Water Services Design and Construction Standards for Sanitary Sewer and Surface Water Management (R &O 04 -9). 6.5 DOWNSTREAM ANALYSIS Per City of Tigard staff, a downstream analysis is not required. l i( .D: . / C p f J 12562 sw main street, tigard or - Google Maps Page 1 of 1 G . . . , 1 1 I , , Address 12562 SW Main St Get Google Maps on your phone Portland, OR 97223 Text the word "GMAPS "to466453 i~,taps ` � f I . Y a Y r 1 v i'1... m s1i , N fia}r14 1 m <='~ S I r 11:77'9 1 I N • D alt.- d S `J 1 Dikni. [ - ryr. w a: rz; I t; 't n sy, Tia rd AV+ 4n C'rifi ''' -- ` p . 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OR 97035 � SHEET r5nt1 995 -8969 _ _ ptmmlaa a wrlcmY nm.aAe -e, g.c , PR 503 -681 -0550 e 9�� O , V OF I FAX: 50 620 -5583 TAX LOT NUMBER 1101 WA4@7GTON COUNTY TAX YAP 2S -1 -02AC • ' n ¢ s a ^: ,tt r a . 2.1 Iy �1 .1 Vii: ''r" l S F,i� t7 , . .. u 1 • bi _ ..... ... - ii i i - 11 25 -,, , ;,,, . _. > Ir �e .� of r ,u� ti' „� ^2?"4" �, • . ir,�. . x . .� ya P . L _ Y F . -. �.. \ 3S sh , 1- f . a x � # 4tk. t L 4 }r j'1 �Si t cs� r : � � y ; . t t , p.. l'y �� is 1 ; l �1 2: _ . . I _ mow.. 4. ..,� (J u '! . .S 1 - �- tY.'tiY 1 S 1R . > IMPERVIOUS AREA 6" PV STM ROUTED TO POND 1P > 2 POND 8" DI STM Subc Reach Pon i Link l Drainage Diagram for 12562 SW MAIN STREET ! , Prepared by AKS ENGINEERING & FORESTRY, LLC., Printed 5/18/2009 HydroCAD® 8.50 s/n 001338 © 2007 HydroCAD Software Solutions LLC 12562 SW MAIN STREET Type IA 24 -hr 25 -YEAR Rainfall= 3.90" Prepared by AKS ENGINEERING & FORESTRY, LLC. Printed 5/18/2009 HydroCAD® 8.50 s/n 001338 © 2007 HydroCAD Software Solutions LLC Page 2 Time span =0.00 -24.00 hrs, dt =0.01 hrs, 2401 points Runoff by SBUH method, Split Pervious /Imperv. Reach routing by Stor- Ind +Trans method - Pond routing by Stor -Ind method Subcatchment 1S: IMPERVIOUS AREA Runoff Area =4,355 sf 100.00% Impervious Runoff Depth >3.66" Tc =5.0 min CN =0/98 Runoff =0.09 cfs 0.030 af Reach 1R: 6" PVC STM Avg. Depth =0.16' Max Vet =1.65 fps Inflow =0.09 cfs 0.030 af D =6.0" n =0.013 L= 101.3' S= 0.0050 '1' Capacity =0.40 cfs Outflow =0.09 cfs 0.030 af Reach 2R: 8" DI STM Avg. Depth =0.09' Max Vet =3.14 fps Inflow =0.09 cfs 0.028 af D =8.0" n =0.013 L =29.3' S= 0.0341 '1' Capacity =2.23 cfs Outflow =0.09 cfs 0.028 af Pond 1P: POND Peak Elev= 150.17' Storage =105 cf Inflow =0.09 cfs 0.030 af Outflow =0.09 cfs 0.028 af 12562 SW MAIN STREET Type IA 24 -hr 25 -YEAR Rainfall= 3.90" Prepared by AKS ENGINEERING & FORESTRY, LLC. Printed 5/18/2009 HydroCAD® 8.50 s/n 001338 © 2007 HydroCAD Software Solutions LLC Page 3 - Summary for Subcatchment 1 S: IMPERVIOUS AREA ROUTED TO POND • Runoff = 0.09 cfs @ 7.88 hrs, Volume= 0.030 af, Depth> 3.66" Runoff by SBUH method, Split Pervious /Imperv., Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs Type IA 24 -hr 25 -YEAR Rainfall= 3.90" Area (sf) CN Description 3,492 98 NEW PAVERS 863 98 EXISTING CONC ROUTED TO POND 4,355 98 Weighted Average 4,355 98 Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Subcatchment 1 S: IMPERVIOUS AREA ROUTED TO POND Hydrograph 0.1 D R u no ff 0.095 E 0.09 cfs 0.09, Type IA 24 -hr 25 -YEAR °0 08 Rainfall=3.90" 0.075, Runoff Area= 4,355 sf 0.065 Runoff Volume= 0.030 of 0.06= u 0.0557 Runoff :Depth >3.66" 0 0.05 LL 0. 045: / Tc =5.0 min 0.04= % CN =0/98 °0.03- 0 0.025 -_ 0.02: 0.015; / '` •%///////// /1//l// / / / / / /1 / / / /1 /// / /// ///// 0.01 - /� 0.005'. 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 Time (hours) 12562 SW MAIN STREET Type IA 24 -hr 25 -YEAR Rainfall = 3.90" Prepared by AKS ENGINEERING & FORESTRY, LLC. Printed 5/18/2009 HydroCAD® 8.50 s/n 001338 © 2007 HydroCAD Software Solutions LLC Page 4 Summary for Reach 1 R: 6" PVC STM Inflow Area = 0.100 ac,100.00% Impervious, Inflow Depth > 3.66" for 25 -YEAR event Inflow = 0.09 cfs @ 7.88 hrs, Volume= 0.030 af Outflow = 0.09 cfs @ 7.91 hrs, Volume= 0.030 af, Atten= 0 %, Lag= 1.8 min Routing by Stor- Ind +Trans method, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs Max. Velocity= 1.65 fps, Min. Travel Time= 1.0 min Avg. Velocity = 0.94 fps, Avg. Travel Time 1.8 min Peak Storage= 6 cf @ 7.89 hrs, Average Depth at Peak Storage= 0.16' Bank -Full Depth= 0.50', Capacity at Bank -Full= 0.40 cfs 6.0" Diameter Pipe, n= 0.013 Length= 101.3' Slope= 0.0050 '/' Inlet Invert= 0.00', Outlet Invert= -0.51' Reach 1 R: 6" PVC STM Hydrograph D Inflow 0.1= 1 0.09cfs 0 Outflo 009 Inflow Area =0.100 ac 0.085- Avg. Depth =0.16' 0.08= 0.075 Max Vet =1.65 fps 0.07 D =6.0 v 0.055 n -0.013 0.05 - LL 0.045- ,����/� L= 101.3' 0.04-. S = 0.0050 ' 0.035- 'P 0.03 0.025- 02 -�'� pty -0.40 cfs 0.015 , /�i i��l�/�/�i�������� �,/' 0.01 - 0.005 0 . 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 Time (hours) 12562 SW MAIN STREET Type IA 24 -hr 25 -YEAR Rainfall= 3.90" Prepared by AKS ENGINEERING & FORESTRY, LLC. Printed 5/18/2009 HydroCAD® 8.50 s/n 001338 © 2007 HydroCAD Software Solutions LLC Page 5 Summary for Reach 2R: 8" DI STM Inflow Area = 0.100 ac,100.00% Impervious, Inflow Depth > 3.39" for 25 -YEAR event Inflow = 0.09 cfs @ 7.92 hrs, Volume= 0.028 af Outflow = 0.09 cfs © 7.93 hrs, Volume= 0.028 af, Atten= 0 %, Lag= 0.3 min Routing by Stor- Ind +Trans method, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs Max. Velocity= 3.14 fps, Min. Travel Time 0.2 min Avg. Velocity = 1.67 fps, Avg. Travel Time 0.3 min Peak Storage= 1 cf © 7.93 hrs, Average Depth at Peak Storage= 0.09' Bank -Full Depth= 0.67', Capacity at Bank -Full= 2.23 cfs 8.0" Diameter Pipe, n= 0.013 Length= 29.3' Slope= 0.0341 '/' Inlet Invert= 0.00', Outlet Invert= -1.00' Reach 2R: 8" DI STM Hydrograph ❑ Inflow 0.1" oo9crs 0 Outflow 0.0954 o.o�ts Inflow Area =0.100 ac 0.09; 0.085; Avg. Depth =0.09' 0.0 . Max Vel - 3.14 fps 0.07; /O 0.065 D =8.0" 0.06' 5 n =0.013 v 0.055= 0 0 .045= 1'I/ LL .045 L -29.3' 0.044 0.0354 � S=0.0341 '/' 0 025- � � , ��•� to , Capacity =2.23 cfs 0.02. . :.� % %%lam % %� %%f /Y/�' / ! /./Ji 0.015 0.01= . ' �/��/�//.�1 0.005: 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 Time (hours) 12562 SW MAIN STREET Type IA 24 -hr 25 -YEAR Rainfall = 3.90" Prepared by AKS ENGINEERING & FORESTRY, LLC. Printed 5/18/2009 HydroCAD® 8.50 s/n 001338 © 2007 HydroCAD Software Solutions LLC Page 6 Summary for Pond 1P: POND Inflow Area = 0.100 ac,100.00% Impervious, Inflow Depth > 3.66" for 25 -YEAR event Inflow = 0.09 cfs @ 7.91 hrs, Volume= 0.030 af Outflow = 0.09 cfs @ 7.92 hrs, Volume= 0.028 af, Atten= 0 %, Lag= 1.1 min Primary = 0.09 cfs @ 7.92 hrs, Volume= 0.028 af Routing by Stor -Ind method, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs Peak Elev= 150.17' @ 7.92 hrs Surf.Area= 154 sf Storage= 105 cf Plug -Flow detention time 93.9 min calculated for 0.028 af (93% of inflow) Center -of -Mass det. time 39.8 min ( 700.4 - 660.7 ) Volume Invert Avail.Storage Storage Description #1 149.00' 539 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq -ft) (cubic -feet) (cubic -feet) 149.00 29 0 0 150.00 132 81 81 151.00 261 197 277 151.80 395 262 539 Device Routing Invert Outlet Devices #1 Primary 149.00' 0.2" Vert. Orifice /Grate C= 0.600 #2 Primary 150.12' 2.3' long Sharp- Crested Rectangular Weir 2 End Contraction(s) 1.1' Crest Height Primary OutFlow Max =0.09 cfs @ 7.92 hrs HW= 150.17' (Free Discharge) 1 1= Orifice /Grate (Orifice Controls 0.00 cfs © 5.19 fps) 2= Sharp- Crested Rectangular Weir (Weir Controls 0.09 cfs © 0.75 fps) 12562 SW MAIN STREET Type IA 24 -hr 25 -YEAR Rainfall= 3.90" Prepared by AKS ENGINEERING & FORESTRY, LLC. Printed 5/18/2009 HydroCAD® 8.50 s/n 001338 © 2007 HydroCAD Software Solutions LLC Page 7 Pond 1P: POND Hydrograph p Inflow II 0.14 I o.os cis _ ❑ Primary 0.0954 o.o9cis Inflow Area= 0.100.. ac - 0.09 0.0854 Peak EIev =150.17' 0.08 00077 Storage =105 cf 0.065 in 0.06: .. 13 0.055 _ 33 0.05 . E 0.045- , 0.04- ' 0.035 0.03 0.025- ,// ,j 1 :(i!" . 0.02 - ._ Ii� ��j/ir /r/Z 0.015 0.01; / / / / / / /// // 0.005 . 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 Time (hours) • \ / \ c t\ , \ \ • Eau 2 ^ .,e ( \ \.». . . _ ± , \ ` \ ^ * r j + - { a \ • t ? - ( , \\ • ° ° - \ \ \ , , e g % e . r \. z w / a a . v » , • x y , • . . , . . _. , . . . . • » _ .. . \ ~� � \� \ \ \ S \\ � » < 3,3 n ° • e r . y y a 1 . _ & 1 ! \ «\% ƒ \ ^ƒ «G» Kam\ » f «. • ƒ •. � ¢ :. � 6 / � • F I C } : «: a g j t 1S 1R IMPERVIOUS AREA 6" PV STM ROUTED TO POND 1,P > 2R POND - 8 "DISTM - , /\ - - \-- S ubcat Reach P on a� Link Drainage Diagram for 12562 SW MAIN STREET I I Prepared by AKS ENGINEERING & FORESTRY, LLC., Printed 5/18/2009 HydroCAD® 8.50 s/n 001338 © 2007 HydroCAD Software Solutions LLC 12562 SW MAIN STREET Type IA 24 -hr 100 -YEAR Rainfall = 4.50" Prepared byAKS`ENGINEERING & FORESTRY, LLC. Printed 5/18/2009 HydroCAD® 8.50 s/n 001338 © 2007 HydroCAD Software Solutions LLC Page 2 Time span =0.00 -24.00 hrs, dt =0.01 hrs, 2401 points Runoff by SBUH method, Split Pervious /Imperv. Reach routing by Stor- Ind +Trans method - Pond routing by Stor -Ind method Subcatchment 1S: IMPERVIOUS AREA Runoff Area =4,355 sf 100.00% Impervious Runoff Depth >4.26" Tc =5.0 min CN =0/98 Runoff =0.11 cfs 0.035 af Reach 1R: 6" PVC STM Avg. Depth =0.18' Max Vet =1.72 fps Inflow =0.11 cfs 0.035 af D =6.0" n =0.013 L= 101.3' S= 0.0050 '1' Capacity =0.40 cfs Outflow =0.11 cfs 0.035 af Reach 2R: 8" DI STM Avg. Depth =0.10' Max Vet =3.28 fps Inflow =0.11 cfs 0.033 af D =8.0" n =0.013 L =29.3' S= 0.0341 '1' Capacity =2.23 cfs Outflow =0.11 cfs 0.033 af Pond 1P: POND Peak Elev= 150.18' Storage =106 cf Inflow =0.11 cfs 0.035 af Outflow =0.11 cfs 0.033 af 12562 SW MAIN STREET Type IA 24 -hr 100 -YEAR Rainfall= 4.50" Prepared by AKS ENGINEERING & FORESTRY, LLC. Printed 5/18/2009 HydroCAD® 8.50 s/n 001338 © 2007 HydroCAD Software Solutions LLC Page 3 Summary for Subcatchment 1S: IMPERVIOUS AREA ROUTED TO POND Runoff = 0.11 cfs @ 7.88 hrs, Volume= 0.035 af, Depth> 4.26" Runoff by SBUH method, Split Pervious /Imperv., Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs Type IA 24 -hr 100 -YEAR Rainfall= 4.50" Area (sf) CN Description 3,492 98 NEW PAVERS 863 98 EXISTING CONC ROUTED TO POND 4,355 98 Weighted Average 4,355 98 Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Subcatchment 1S: IMPERVIOUS AREA ROUTED TO POND Hydrograph 0.115 ❑ Runoff 0.11= O t cfs Type IA 24 -hr 10 -YEAR 0.1= °009: - Rainfall= 4.50" 0.08. � Runoff Area =4,355 sf y0.075" Runoff Volume = .0:035 af • 0.07• 0.065 Runoff :Depth >4.26 0.06 LL0oo5- Tc =5.0 min 0.045 • CN =0198 0.035=, .• 0.015" • 4�� 0.01- i 0.005- ' 0 1 2 ' 3 4 5 6 789 10 1 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) 12562 SW MAIN STREET Type IA 24 -hr 100 -YEAR Rainfall = 4.50" Prepared by AKS ENGINEERING & FORESTRY, LLC. Printed 5/18/2009 HydroCAD® 8.50 s/n 001338 © 2007 HydroCAD Software Solutions LLC Page 4 Summary for Reach 1 R: 6" PVC STM Inflow Area = 0.100 ac,100.00% Impervious, Inflow Depth > 4.26" for 100 -YEAR event Inflow = 0.11 cfs @ 7.88 hrs, Volume= 0.035 af Outflow = 0.11 cfs @ 7.90 hrs, Volume= 0.035 af, Atten= 0 %, Lag= 1.7 min Routing by Stor- Ind +Trans method, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs Max. Velocity= 1.72 fps, Min. Travel Time 1.0 min Avg. Velocity = 0.99 fps, Avg. Travel Time= 1.7 min Peak Storage= 6 cf © 7.89 hrs, Average Depth at Peak Storage= 0.18' Bank -Full Depth= 0.50', Capacity at Bank -Full= 0.40 cfs 6.0" Diameter Pipe, n= 0.013 Length= 101.3' Slope= 0.0050 '/' Inlet Invert= 0.00', Outlet invert= -0.51' 0 Reach 1 R: 6" PVC STM Hydrograph ❑ Inflow 0.115= ()lids O Outflo 0.11- 0.11ds Or Inflow Area= 0.100 ac ° A . De th =0.18" 0.095- % % Max Vel 1.72 fps 0.075- / /�/ n m 0.07 = $� �/ n =0.013 x 0.065= 0 0.055; L =101.3' LL 0.05'. S= 0.0050 '1' 0.04-, 1 ' % 0.035; � � 0.03= %,�i Capacity =0.40 cfs 0.025: �� `' !' A ,goir �.�ieifi//f` 0.02= // /i . 1����� .��/.I��.���i.������i���J���� �/� 0.015 0.01 0.005 -z 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 Time (hours) 12562 SW MAIN STREET Type IA 24 -hr 100 -YEAR Rainfall= 4.50" Prepared by AKS ENGINEERING & FORESTRY, LLC. Printed 5/18/2009 HydroCAD® 8.50 s/n 001338 © 2007 HydroCAD Software Solutions LLC Page 5 Summary for Reach 2R: 8" DI STM Inflow Area = 0.100 ac,100.00% Impervious, Inflow Depth > 3.98" for 100 -YEAR event Inflow = 0.11 cfs @ 7.92 hrs, Volume= 0.033 af Outflow = 0.11 cfs @ 7.92 hrs, Volume= 0.033 af, Atten= 0 %, Lag= 0.3 min Routing by Stor- Ind +Trans method, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs Max. Velocity= 3.28 fps, Min. Travel Time 0.1 min Avg. Velocity = 1.76 fps, Avg. Travel Time 0.3 min Peak Storage= 1 cf @ 7.92 hrs, Average Depth at Peak Storage= 0.10' Bank -Full Depth= 0.67', Capacity at Bank -Full= 2.23 cfs 8.0" Diameter Pipe, n= 0.013 Length= 29.3' Slope= 0.0341 '/' Inlet Invert= 0.00', Outlet Invert= -1.00' Reach 2R: 8" DI STM Hydrograph 0 Inflow 0.115'. " 1 0.11 cfs 0 Outflow 0.11= 0.11 cfs Inflow Area =0.100 ac % Avg. Depth-0.10' p 0 085 - Max Vet 3.28 f S 0.08- D =8.0" 0.65 0.065 n =0.013 0.06— o 0.055, L =29.3 0.045 ", " S= 0.0341 '1' 0.04 aci# =2.23 cfs 0.035-' . • 0.03" " '4 Cap y cfs / � //.IA � I � �.'�f��//.� 0.02-: �' I��l ��l��� ������ .������`��������������.������� 0.015 0.01: '� p . 1 _ 2 . 3 .... 4 ... 5... 6 7....8. 9 10 11 12 13 14 ... .. 16 17 ... .... ... 18 19 9 2 20 21 22 23 24 Time (hours) 12562 SW MAIN STREET Type IA 24 -hr 100 -YEAR Rainfall =4.50" Prepared by AKS ENGINEERING & FORESTRY, LLC. Printed 5/18/2009 HydroCAD® 8.50 s/n 001338 © 2007 HydroCAD Software Solutions LLC Page 6 Summary for Pond 1P: POND Inflow Area = 0.100 ac,100.00% Impervious, Inflow Depth > 4.25" for 100 -YEAR event Inflow = 0.11 cfs @ 7.90 hrs, Volume= 0.035 af Outflow = 0.11 cfs @ 7.92 hrs, Volume= 0.033 af, Atten= 0 %, Lag= 0.9 min Primary = 0.11 cfs @ 7.92 hrs, Volume= 0.033 af Routing by Stor -Ind method, Time Span= 0.00 -24.00 hrs, dt= 0.01 hrs Peak Elev= 150.18' @ 7.92 hrs Surf.Area= 155 sf Storage= 106 cf Plug -Flow detention time 82.2 min calculated for 0.033 af (94% of inflow) Center -of -Mass det. time 35.1 min ( 692.4 - 657.3 ) Volume Invert Avail.Storage Storage Description #1 149.00' 539 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq -ft) (cubic -feet) (cubic -feet) 149.00 29 0 0 150.00 132 81 81 151.00 261 197 277 - 151.80 395 262 539 Device Routing Invert Outlet Devices #1 Primary 149.00' 0.2" Vert. Orifice /Grate C= 0.600 #2 Primary 150.12' 2.3' long Sharp- Crested Rectangular Weir 2 End Contraction(s) 1.1' Crest Height Primary OutFlow Max =0.11 cfs @ 7.92 hrs HW= 150.18' (Free Discharge) 'L 1= Orifice /Grate (Orifice Controls 0.00 cfs @ 5.21 fps) 2= Sharp- Crested Rectangular Weir (Weir Controls 0.10 cfs @ 0.79 fps) 12562 SW MAIN STREET Type IA 24 -hr 100 -YEAR Rainfall = 4.50" Prepared by AKS ENGINEERING & FORESTRY, LLC. Printed 5/18/2009 HydroCAD® 8.50 s/n 001338 © 2007 HydroCAD Software Solutions LLC Page 7 Pond 1P: POND Hydrograph / -- - Olnflow 0.115= .. . I 0.11 cfs .. . 0 Primary 0 105= . " :c1 Inflow Are. a 0.100 ac % % 01- �� Peak EI'ev= 150.18'' 0.095 �/ / r 0 85- Storage =1 cf 0.78: A % • 0.0757 . % 0.065 .. 3 0.06= 4 0 0.0554 1 / . LL 0 . 0 5 4. • 0 0.04 0.03: % • 0 " 0.025= �� � , rri 1,. - 0.015 7.- ii✓ iiii �i fi ii f 0.01 0.005 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 Time (hours) 1". # 6 « ) y : \ ''" a ` \\ § It )( { A \' & 7 « a( G m « s q 3 A J t R / ~ \ x \y y( <�/ 2 Q 2:) %® . y , ( � y1 9� @ § ®< § / \ ` 4 « ( § } [ . - - f ® Q/ © 4.' x. , ■ . } «« ems g cam A? & § » \ , : a & ; . Q / 6 k , � I . \ \ . v , , \ w 6 m . . . � �� . � %� / r , 12562 SW MAIN STREET Water Quality Calculations Total Site Area = 24,864 SF Existing Impervious Area = 10,161 SF Existing Impervious Area Disturbed by Redevelopment = 0 SF Per CWS Table 4 -1, no new treatment required for existing impervious area. New Impervious Area = 3,492 SF (Pavers) 0.36 "(3 492 ft Water Quality Volume = 1 2 104.76 CF Water Quality Drawdown Time = 48 HRS 104.76 ft Water Quality Flow = = 0.0006 CFS 48hrs x 60 minx 60 sec Q (CFS) = Cd(2gH 4 — 05 40 D (FT) _ Cd;z(2gH) - D = Diameter of orifice Q = Water flow Cd = Discharge coefficient (0.62) H = 2 / 3 x temporary detention height to centerline of orifice H = % x (150.12 — 149.00') = 0.75 FT —os 4(0.0006) D = 0.0133' = 0.16" ■ = 0.62rr(2 x 32.17 x 0.75r r fa �f { } i .'yi p LEVA I;a r _ - . "—" 6 a � t is ��,� r Z R; F , _ k � T x 1 r 7 < c H 2, I A , • t f .a Ii H 4 s � i a • , , ._ , .. • sv: Y l j• i . ° i _.. � k f 1 Y 1 ' t� 1. IJ . • f a i i f � F C 1�