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HomeMy WebLinkAboutDrainage Reports - 06/18/2003If Final Approved Report N MAY 2 0 2W3 Date Oilos Pit OJ'T OF FORT COLLMS UTHXr Final Drainage and Erosion Control Report For First Free Will Baptist Church Fort Collins Colorado Prepared for First Free Will Baptist Church 320 West Trilby Road Ft Collins Colorado 80527 Prepared by Shear Engineering Corporation Project No 1785 01 00 Date May 2003 4836 S College Suite 12 Ft Collins CO 80525 (970) 226 5334 Fax (970) 282 0311 wwwshearengmeenng com r F--1 V 0 0 0 N II Final Drainage and Erosion Control Report for First Free Will Baptist Church Project No 1785 01 00 TABLE OF CONTENTS TITLE PAGE VICINITY MAP TABLE OF CONTENTS I INTRODUCTION 3 II GENERAL LOCATION AND DESCRIPTION 3 A LOCATION 3 B DESCRIPTION OF PROPERTY 3 III DRAINAGE BASINS AND SUB BASINS 4 A MAJOR BASIN DESCRIPTION 4 B SUB BASIN DESCRIPTION 4 IV DRAINAGE DESIGN CRITERIA 6 A REGULATIONS 6 B DEVELOPMENT CRITERIA REFERENCE AND CONSTRAINTS 6 C HYDROLOGICAL CRITERIA 7 D HYDRAULIC CRITERIA 7 V DRAINAGE FACILITY DESIGN 7 A GENERAL CONCEPT 7 B SPECIFIC DETAILS - DETENTION POND 7 C SPECIFIC DETAILS -STORM SEWERS 9 D SPECiriCDETAILS SWALES 10 VI EROSION CONTROL AND WATER QUALITY 10 A GENERAL CONCEPT 10 B SPECIFIC DETAILS - WATER QUALITY 10 C SPECIFIC DETAILS - EROSION CONTROL 11 D SPECIFIC DETAILS RIPRAP 12 E EROSION CONTROL SECURITY DEPOSIT 12 VII CONCLUSIONS 13 A COMPLIANCE WITH STANDARDS 13 B DRAINAGE CONCEPT 13 VIII REFERENCES 13 APPENDIX I — Drainage Calculations APPENDIX 11 — Charts and Figures APPENDIX III —Erosion Control APPENDIX IV — Stuffer Envelope 2 Final Drainage and Erosion Control Report for First Free Will Baptist Church Project No 1785 01 00 I INTRODUCTION 1 This report presents the pertinent data methods assumptions references and calculations used in analyzing and preparing the preliminary drainage and erosion control design for the First Free Will Baptist Church site H GENERAL LOCATION AND DESCRIPTION A LOCATION 1 First Free Will Baptist Church is located in the SE quarter of section 11 Township 6 North Range 69 West of the 6th P M Fort Collins Colorado 2 More specifically it is located approximately 950 feet west of the intersection of South College Avenue (State Highway 287) and West Trilby Road on the north side of West Trilby Road 3 The site is bounded on the north and west by Skyview Subdivision 1 Filing which is fully developed This property is bounded on the east by the Timan Property which is currently undeveloped The site is bounded on the south by West Trilby Road This property was previously platted as Skyview Subdivision 3 d Filing 4 Located just east of the east boundary is Louden Ditch which culverts underneath West Trilby Road B DESCRIPTION OF PROPERTY 1 The property currently consists of church building which covers 3300 sq ft On the north side of the church building there is a gravel playground which covers 1544 sq R 2 Development of the site will consist of an addition onto the east side of the existing church which will cover about 12 842 sq ft This new addition will be used for an auditorium and some classrooms There will be a concrete walk along the south and east sides of this new addition Development of the site will also consist of paving the parking lot This pavement will provide access from West Trilby Road and will surround the church 3 West Trilby Road is located along the southern border of the property This road is forty feet (40 ) wide with twenty feet (20 ) on this property A swale does exist along the interim road condition to convey runoff This drainage design has assumed that Trilby Road will be improved in the 3 Final Drainage and Erosion Control Report for First Free Will Baptist Church Project No 1785 01 00 future This road has been assumed to be fifty two feet (52 ) wide with twenty six feet (26 ) located on this property A curb and gutter has been assumed for the future development of West Trilby Road for the ultimate condition 4 The site has a net area of approximately five (5) acres III DRAINAGE BASINS AND SUB BASINS A MAJOR BASIN DESCRIPTION 1 The site is located within the Fossil Creek Basin as defined on the City of Fort Collins Master Stormwater Basin Map (See Appendix H) The City has completed updating the master plan for this basin 2 The City of Fort Collins describes Fossil Creek Basin as a Total area covers 32 square miles b The current use is mostly urban and rural c Problems within this basin are mainly due to instability of stream banks along Fossil Creek and its tributaries as well as overtopping roads d The original master plan was completed in 1982 e The city is working in conjunction with Lanmer County on this master plan update f Detention is required for this basin to detain the 100 yr storm at a 2 yr historic release rate 3 The ultimate destination for Fossil Creek is Fossil Creek Reservoir B SUB BASIN DESCRIPTION 1 The site generally slopes towards the southeast corner of the site 2 Historically stormwater runoff from the site flows overland into the swale along the north side of West Trilby Road Drainage is conveyed east within this swale 4 Final Drainage and Erosion Control Report for First Free Will Baptist Church Project No 1785 01 00 3 Development of the site has divided the site into 2 sub basins which have been labeled sub basin A and sub basin B (See Drainage and Erosion Control Plan) a Sub basin A i This is the northern sub basin for this development Most of the site is contained within this sub basin along with the building parking lot and the detention pond ii All runoff from this sub basin contributes to the detention pond ►►i Sub basin A covers approximately 4 46 acres ►v A minor basin Al has been delineated to calculate the amount of runoff which is conveyed to the upslope side of the culvert underneath the access to the church Minor basin Al covers approximately 0 52 acres b Sub basin B i This is the southern sub basin for this development Within this sub basin the northern half of the future development of West Trilby Road adjacent to this site is contained ii Only a portion of the runoff from this sub basin contributes to the detention pond Note that the release rate from the detention pond is restricted to compensate for this increase in runoff iii Sub basin B covers approximately 0 67 acres iv For the development of the site this sub basin will remain in an interim condition until West Trilby Road is developed and then the ultimate condition will apply c Sub basin H I This is the historical sub basin for the development This sub basin covers the same area as both sub basin A and sub basin B for the developed conditions with the design point located in the southeastern corner of the site n This historical basin consists of a church building which covers 3300 sq ft On the north side of the church building there is a gravel playground which covers 1544 sq ft Located east of the 5 Final Drainage and Erosion Control Report for First Free Will Baptist Church Project No 1785 01 00 church building are two gazebos which cover approximately 175 sq ft each in Sub basin H covers approximately 6 18 acres ►v For further specifics please see the historic plan in Appendix IV IV DRAINAGE DESIGN CRITERIA A REGULATIONS 1 Design Criteria from the City of Fort Collins Storm Drainage Design Criteria Manual and options for storm drainage improvements discussed by the City of Fort Collins were considered 2 Water quality control measures and erosion control criteria were considered from the Urban Storm Drainage Criteria Manual by the Urban Drainage and Flood Control District B DEVELOPMENT CRITERIA REFERENCE AND CONSTRAINTS 1 The surrounding areas on the north and south sides are completely developed The property to the east is currently undeveloped 2 All grading along the west north and east property lines will match existing grades 3 Grading along the south property line will be in an interim condition and will match future grade for the development of West Trilby Road for the ultimate condition 4 Water quality provisions are required for and within the limits of this site 5 Additional right of way for West Trilby Road is dedicated along the frontage of First Free Will Baptist Church with this replat A fifteen (15 ) utility easement is also provided along the frontage of the common open space 6 Detention will be provided in order to restrict release rates from the site to less than or equal to historic release rates 31 Final Drainage and Erosion Control Report for First Free Will Baptist Church Project No 1785 01 00 C HYDROLOGICAL CRITERIA The Rainfall Intensity Duration curves for the City of Fort Collins were used (Figure 3 1 attached for reference in Appendix II) in conjunction with the Rational Method for deterrmning peak flows at various concentration points The Rainfall Intensity Duration Frequency Table was used in conjunction with the Rainfall Intensity Duration curve which provides the exact same data (see Appendix II) 2 The two (2) and one hundred (100) year storms were analyzed in accordance with Table 3 1 of the City of Fort Collins Storm Drainage Design Criteria Manual for commercial sites D HYDRAULIC CRITERIA i Storm sewer and drainage channel capacities are based on the Manning s Equation The Manning s coefficient is in accordance with the City of Fort Collins Storm Drainage Criteria Manual Haestad Method Flowmaster v5 13 was used in the calculation of storm sewers and channel capacities V DRAINAGE FACILITY DESIGN A GENERAL CONCEPT I The historic flow patterns will be maintained with the development of this site In developed conditions stormwater will be conveyed through the site via a combination of overland flow swales and gutters 2 For the development of this property there will be two phases of construction This drainage design has incorporated both phases of construction 3 The future development of West Trilby Road has been considered in this analysis and the detention pond has been sized in consideration of Trilby Road being developed 4 A water quality/detention pond will be provided in the southeast corner of the site Runoff will be released at historic rates along West Trilby Road B SPECIFIC DETAILS DETENTION POND 1 A detention pond is located in the southeastern corner of the property to provide temporary volume for storm runoff while this runoff is being 7 Final Drainage and Erosion Control Report for First Free Will Baptist Church Project No 1785 01 00 restricted to historic flows This volume also incorporates the water quality control volume which is located in the base of this detention pond 2 The detention pond has been sized for developed onsite conditions only all offsite drainage will convey through the detention pond 3 The detention pond sizing specifics are as follows a The detention pond will have volume of 0 85 ac ft (37023 cf) This volume incorporates the water quality control volume of 0 12 ac ft (5030 cf) b The detention pond has a 100 yr water surface elevation of 5054 36 ft c The top of the berm has an elevation of 5055 50 ft which will provide 1 14 ft of freeboard Please note that the lowest elevation in the parking lot is 5058 92 ft which would still allow the event of a 500 yr storm the runoff to have the ability to overflow the top of berm and continue its historical flow path d For additional specifics please see detention in Appendix I 4 The detention pond release flow specifics are as follows a An outlet structure will be located at the southeastern corner of the detention pond to control release rates and ponding elevations On the northwest side of the outlet structure a metal plate will be placed to provide the proper release rates for water quality Another metal plate will be placed inside the outlet structure to release the historic 2 year release rate ii The outlet pipe from this structure will be 15 inch ADS N12 pipe This pipe will convey the 2 year historic release rate of 1 44 cfs with a flow depth of 0 45 ft b The release rate from the pond is restricted to 144 cfs i The release rate is controlled by a 5 7/8 inch diameter orifice (See onfice release in Appendix I) This orifice plate will be placed inside the box of the outlet structure u The release rate is also controlled by 3 orifice for the Water Quality Control Pond There will be two 11/16 orifices and one 5/8 orifice which will a 40 hour dram time release of 0 035 cfs H Final Drainage and Erosion Control Report for First Free Will Baptist Church Project No 1785 01 00 c In emergency situations with the detention pond being occupied while a 100 year storm occurs the top of the berm along the eastern and southern sides of the detention pond provide an emergency overflow weir i The top of berm has an elevation of 5055 50 ft and is approximately 323 ft in length ii The water surface of 100 year storm passing over this berm is 5055 59 ft This 100 year storm is 22 29 cfs flowing at a depth of 0 09 ft (See Weir in Appendix I) 5 For further specifics please see detention and water quality volume calculations in Appendix I C SPECIFIC DETAILS STORM SEWERS 1 A 15 ADS N 12 will convey stormwater from the detention pond outlet box located in the detention pond to the southern side of the berm a This pipe will be able to convey the historic 2 year release of 144 cfs with a water depth of 0 45 ft b This is classified as storm sewer C in the plan set 2 A 15 ADS N 12 will convey stormwater from the proposed manhole into the detention pond a This will be suitable to convey 7 42 cfs from a 100 yr storm with a flow depth of 7 7 inches b This is classified as storm sewer B in the plan set 3 A 15 RCP will convey stormwater underneath the access to the property from West Trilby Road a This will be suitable to convey the 100 yr runoff of 4 02 cfs design point al with a flow depth of 6 6 inches b This is classified as storm sewer A in the plan set 4 An existing 15 RCP will conveys stormwater from along the north side of West Trilby Road 9 Final Drainage and Erosion Control Report for First Free Will Baptist Church Project No 1785 01 00 a This will be suitable to convey the 100 yr developed flow from sub basin B of 4 60 cfs with a flow depth of 6 7 inches b For development purposes of the site this culvert will be extended by five feet (5 ) on each end c This existing 15 RCP will remain in place 5 For further specifics please see inlets in Appendix I D SPECIFIC DETAILS SWALES 1 Swale Z Z is located below the 24 ADS N 12 outfall pipe for the detention pond This swale will convey developed onsite and existing offsite runoff to the east side of Louden Ditch 2 With 22 29 cfs flowing through the swale it will have a depth of 1 39 ft 3 For further information see swales in Appendix I VI EROSION CONTROL AND WATER QUALITY A GENERAL CONCEPT 1 Erosion control measures are specified on the Drainage and Erosion Control Plan 2 Maintenance of erosion control devices will remain the responsibility of the contractor and the owner until the project is complete 3 A water quality pond will be constructed in the southeast corner of the site within the limits of the detention pond B SPECIFIC DETAILS — WATER QUALITY POND 1 The water quality pond will be located in the base of the detention pond for this site 2 The water quality pond will be built to the following specifications a The water quality pond will have a volume of 0 12 ac ft (5030 co b The water quality water surface elevation is 5052 89 ft 10 Final Drainage and Erosion Control Report for First Free Will Baptist Church Project No 1785 01 00 c This is based on a resultant impervious in the property of fifty percent (50%) 3 The release device for the water quality pond will allow a dram time of 40 hours and will be built to the following specifications a The release rate will be 0 035 cfs b This release rate will be controlled by three (3) orifice holes places strategically in the metal plate on the northwestern side of the 4 x4 box in the detention pond i There will be two rows of orifices which will be set four inches (4 ) apart it The bottom row will consist of two 11/16 holes set 3 apart O C in The top row will consist of one 5/8 hole set O C 4 A water quality outlet device is specified on the plan set A detail is provided on the detail sheet 5 A US Filter Stainless Steel well screen will be provided in front of the water quality orifice plate This screen will have the following specifications i Screen #93 VEE Wire Slot Opening 0 139 it Support Rod Type #156 VEE m Support Rod On Center spacing = 3/4 iv Total Screen Thickness = 0 31 v Carbon Steel Frame Type = 3/8 x1 0 flat bar 6 For further specifics please see water quality control in Appendix I C SPECIFIC DETAILS- EROSION CONTROL 1 The following temporary erosion control measures are specified on the Drainage and Erosion Control plan a Haybales in the swales 11 Final Drainage and Erosion Control Report for First Free Will Baptist Church Project No 1785 01 00 b Silt fence on the downstream property lines specifically the east property line c A wheel cleaning station is called for at the entrance to the site D SPECIFIC DETAILS RIPRAP I Rjprap is used to reduce the velocity of stormwater in order to prevent erosion typically on the end of conduits 2 Located at the end of the outfall pipe from the manhole into the detention pond will be Class L riprap a This will have a D50 equal to nine inches (9 ) b This will have a length of 3 75 ft from the end of the conduit c This will have a final apron width of 5 00 ft 3 For the interim condition located at the end of the four foot (4 ) concrete channel in the southeastern corner of the site will be Class L nprap a This will have a D50 equal to nine inches (9 ) b This will have a length of 3 75 ft from the end of the channel c This will have a final apron width of 5 00 ft 4 For further specifics please see riprap in Appendix I E EROSION CONTROL SECURITY DEPOSIT 1 An erosion control security deposit is required in accordance with City of Fort Collins policy In no instance shall the amount of the security be less than $1000 00 2 See the Erosion Control Security Deposit Requirements document located in Appendix III 3 The erosion control security deposit is reimbursable 4 The erosion control security deposit is equal to $4912 50 12 Final Drainage and Erosion Control Report for First Free Will Baptist Church Project No 1785 01 00 VII CONCLUSIONS A COMPLIANCE WITH STANDARDS 1 All drainage analysis has been performed according to the requirements of the City of Fort Collins Storm Drainage Criteria Manual 2 Proposed drainage improvements generally conform to the recommendations of the City of Fort Collins Master Drainage Plan 3 Proposed erosion control measures conform to the recommendations of the City of Fort Collins standards B DRAINAGE CONCEPT 1 The proposed drainage design for First Free Will Baptist Church is effective for the control of storm runoff with a considerable reduction in potential downstream effects 2 The proposed drainage design for First Free Will Baptist Church will have no effect on City of Fort Collins Master Drainage Plan recommendations 3 The proposed drainage design will release up to a 100 yr storm runoff at the historic 2 yr storm runoff release VIII REFERENCES City of Fort Collins Storm Drainage Design Criteria and Construction Standards March 1997 City of Fort Collins Erosion Control Reference Manual January 1991 Urban Drainage and Flood Control District Urban Strom Drainage Criteria Manual Volume 1 March 1969 Urban Drainage and Flood Control District Urban Strom Drainage Criteria Manual Volume 2 March 1969 Urban Drainage and Flood Control District Urban Storm Drainage Criteria Manual Volume 3 September 1 1999 13 Final Drainage and Erosion Control Report for First Free Will Baptist Church Project No 1785 01 00 Appendix I Drainage Calculations Runoff Coefficients Runoff Calculations Storm Sewers Swales Riprap Detention Orifice Release Weir Water Quality Control Job No 1785 01 00 First Free Will Baptist Church Designer SWT Shear Engineering Corporation Runoff Coefficients 4/22/2003 3 50 PM Job No 1785 01 00 Shear Engin ering Corporation Designer SWT First Free Will Baptist Church Runoff Coeffecient Summary Developed Condition Sub Basin Area (ac) C2 C100 A 02 5 51 0 43 0 54 Al 01 0 85 0 46 0 58 B 0 67 0 63 0 79 03 0 17 0 20 0 25 Historic Conditions Sub Ba in Area (ac) C2 C100 H 1 6 18 0 21 0 26 Entire Site 15 00 0 21 0 27 4/22/2003 3 49 PM Final Drainag Calc (Fir t Free Will B pti t) Page 1 of 1 C Job No 1785 01 00 Shear Engineering Corporation Designer SWT First Free Will Bapti t Church 4/22/2003 3 50 PM Historic Conditions Minor Basins Ba in Ground Cover H Area (ft ) Area (ac) Percent Area C 2 yr Storm Weighted C Lawn/Gra se 264515 21 6 07 98 201; 0 20 0 20 Gravel 1544 00 0 04 0 57% 0 50 0 00 Pavement/Roof 3300 00 0 08 1 23t 0 90 0 01 269359 21 6 18 0 21 Basin Entire Site 2 yr Storm Ground Cover Area (ft ) Area (ac) Percent Area C Weighted C Lawn/Gra. a 212956 00 4 89 97 7891 0 20 0 20 Gravel 1544 00 0 04 0 71% 0 50 0 00 Pavement/Roof 3300 00 0 08 1 52t 0 90 0 01 217800 00 5 00 0 21 Final Drainage Calcs (Fir t Free Will Bapti t) Page 1 of 1 C Job No 1785 01 00 Shear Engineering Corporation Designer SWT First Free Will Baptist Church 4/22/2003 3 50 PM Developed Conditions Basin Ba in A 02 2 yr Storm Ground Cover Area (ft ) Area (ac) Percent Area C Weighted C Lawn/Grasses 159370 21 3 66 66 40% 0 20 0 13 Gravel 1544 00 0 04 0 64% 0 50 0 00 Pavement/Roof 79113 00 1 82 32 96% 0 90 0 30 240027 21 5 51 0 43 Ba in B 2 yr Storm Ground Cover Area (ft ) Area (ac) Percent Area C Weighted C Lawn/Grasses 11107 00 0 25 37 871; 0 20 0 08 Pavement/Roof 18225 00 0 42 62 13% 0 90 0 56 29332 00 0 67 �0 63 Minor Ba in Al 01 2 yr Storm Ground Cover Area (ft ) Area (ac) Percent Area C W ighted C Lawn/Gra se 23166 30 0 53 62 44% 0 20 0 12 Pavement/Roof 13935 92 0 32 37 56% 0 90 0 34 37102 22 0 85 II 0 46 II M nor Ba n 03 2 yr Storm Ground Cover Area (ft ) Area (ac) Percent Area C W ighted C Lawn/Gra es 7564 30 0 17 100 00% 0 20 0 20 7564 30 0 17 0 20 Minor Basin Entire Site 2 yr Storm Ground Cover Area (ft ) Area (ac) Percent Area C Weighted C Lawn/Gra a 120287 16 2 76 55 27% 0 20 0 11 Pavement/Roof 97338 00 2 23 44 73% 0 90 0 40 217625 16 5 00 0 51 Final Drainage Calc (Fir t Fre W 11 Bapti t) Page 1 of 1 C Job No 1785 01 00 First Free Will Baptist Church Designer SWT Shear Engineering Corporation 4/22/2003 4 02 PM Runoff Calculations Job iu 1785 01 00 Shear EngineL ng Corporation 4 /2003 Designer SWT First Free Will Baptist Church 9 24 AM Historic Site Breakdown Area Q2 Q100 Design Point Sub basin acres h H 6 18 1 72 7 65 Entire Site Entire Site 5 00 1 44 6 38 Developed Site Breakdown Area Q2 Q100 Design Point Sub basin acres a A 02 5 51 5 11 22 29 al Al 01 0 85 0 97 4 02 b B 0 67 1 11 4 60 osl OS1 0 33 0 34 1 55 os2 OS2 1 05 1 11 4 86 os3 OS3 0 17 7 1 Final Drainage Calcs (First Free Will Baptist) QSum Page 1 of 8 It Job No 1785 01 00 Shear Engineering Corporation 4/22/2003 Designer SWT First Free Will Baptist Church 4 03 PM Historic Conditions Design Pt h Sub basins H Rational Method All Rainfall Intensities taken from Larimer County Storm Water Management Manual Fia 3 3 1 1 Area I Fort Collins Runoff Coefficients C - - - - - - 2 yr 0 21 - - - - - - - - - 100 yr 0 26 Intensity Duration Frequency - - - - - - 7ime of Concentration - - - - - - - - - Overland Travel Time 1 87 (1 1 C)*L (1/2)/S (1/3) Length = 500 00 ft Slope = 3 80 - 2 yr 100 yr C = 0 21 0 26 Ti (min) = 23 84 22 43 Travel Time (TO Length (ft) lope (-)Flow Type Column Velocity Tt(min) 373 0 50 Swale 6 1 11 5 60 I 8 0 00 0 00 8 0 00 0 00 8 0 00 0 00 Total Travel Time = 5 60 Time of Concentration (Tc) 2 yr 100 yr Total Length = 873 Tc = Ti + T 29 44 28 03 2 yr 100 yr Tc (min) = 29 44 28 03 Use Tc = 29 00 28 00 Intensity 2 yr 100 yr I (iph) 1 33 4 70 Area A - - - - - - - - Area = 269359 ft2 - - - - - - - - - - - - Area = 6 18 acres Discharge (Q = C I A) Q Event C I (iph) A (acres) Q (cfs) 2 yr 0 21 1 33 6 18 1 72 100 yr 0 26 4 70 6 18 7 65 uonciusion Time of concentrations were rounded to the nearest whole minutes Tc = L/180+10 is from Urban Drainage & Flood Control District 3 4 2 Final Drainage Calcs (First Free Will Baptist) HQ Page 1 Job No 1785 01 00 Shear Engineering Corporation 4/22/2003 Designer SWT First Free Will Baptist Church 4 03 PM Historic Conditions Design Pt tire Site Sub basins H Rational Method All Rainfall Intensities taken from Larimer County Storm Water Manaaement Manual Fla 3 3 1 1 Area I Fort Collins Runoff Coefficients C — — — — — — — 2 yr 0 21 — — — — — — — — — 100 yr 0 27 Intensity Duration Frequency — — — — — — — — Time of Concentration — — — — — — — — Overland Travel Time 1 87*(1 1 C) L�(1/2)/S (1/3) Length = 500 00 ft Slope = 3 80 s 2 yr 100 yr C = 0 21 0 27 Ti (min) = 23 77 22 35 Travel Time (TO Length (ft) lope (t)Flow Type Column Velocity Tt(min) 340 0 50 Swale 6 1 11 5 11 I 8 0 00 0 00 8 0 00 0 00 8 0 00 0 00 Total Travel Time = 5 11 Time of Concentration (Tc) 2 yr 100 yr Total Length = 840 Tc = Ti + 28 88 27 45 2 yr 100 yr Tc (min) = 28 88 27 45 Use Tc = 28 00 27 00 Intensity 2 yr 100 yr I (lph) 1 35 4 80 Area A — — — — — — — — — Area = 217800 ft2 — — — — — — — — — — — — Trea = 5 00 acres Discharge (Q = C I A) Q — — — — — — — — — Event C I (lph) — — — A (acres) — — — Q (cfs) — — — — — — 2 yr 0 21 1 35 5 00 1 44 100 yr 0 27 4 80 5 00 6 38 conclusion Time of concentrations were rounded to the nearest whole minutes Tc = L/180+10 is from Urban Drainage & Flood Control District 3 4 2 Final Drainage Calcs (First Free Will Baptist) HQ Page 2 Job No 1785 01 00 Shear Engineering Corporation Designer SWT First Free Will Baptist Church Developed Conditions Design Pt a Sub basins A 02 Rational Method All Rainfall Intensities taken from Larimer County Storm Water Manaaement Manual Fia 3 3 1 1 Area I Fort Collins Runoff Coefficients C — — — — — — 2 yr 0 43 — — — — — — — — — 100 yr 0 54 Intensity Duration Frequency — — — — — — Time of Concentration — — — — — — — — — Overland Travel Timel 87*(1 1 C) LA(1/2)/S (1/3) Length = 20 00 ft Slope = 3 80 t 2 yr 100 yr C = 0 43 0 54 Ti (min) = 3 58 3 00 Travel Time (Tt) Length (ftSlope (s)Flow Type Column Velocity Tt (min) 290 0 50 Gutter 7 1 50 3 22 I 340 0 50 Swale 6 1 11 5 11 8 0 00 0 00 8 0 00 0 00 Total Travel Time = 8 33 Time of Concentration (Tc) 2 yr 100 yr Total Length = 650 Tc = Ti + Tt 11 90 11 32 2 yr 100 yr Tc (min) = 11 90 11 32 Use Tc = 11 00 11 00 Intensity 2 yr 100 yr I (iph) 2 14 7 48 Area — — — — — — — — — — — — — A Area = 240027 ft — — — — — — — Area = 5 �1 acres Discharge (Q = C I A) Q — — — — — — — — Event C I (iph) — — — A (acres) — — — — — — Q (cfs) — — — 2 yr 0 43 2 14 5 51 [75 11 100 yr 0 54 7 48 5 51 22 29 conciusion Time of concentrations were rounded to the nearest whole minutes All Valley pans and pipe slopes have been conservately rounded to 0 5- Tc = L/180+10 is from Urban Drainage & Flood Control District 3 4 2 Final Drainage Calcs (First Free Will Baptist) DQ Page 1 4/22/2003 4 44 PM Job No 1785 01 00 Shear Engineering Corporation 4/22/2003 Designer SWT First Free Will Baptist Church 4 03 PM Developed Conditions Design Pt b Sub basins B Rational Method All Rainfall Intensities taken from Larimer County Storm Water Manaqement Manual Fiq 3 3 1 1 Area I Fort Collins Runoff Coefficients C —yr 0 63 — — — — — — 2 — — — — — — — — — — 100 yr 0 79 Intensity Duration Frequency - - - - - - - Time of Concentration - - - - - - - - - - Overland Travel Time (Ti 87 (1 1 C) L (1/2)/S (1/3) Length = 15 00 ft Slope = 6 67 s 2 yr 100 yr C = 0 63 0 79 Ti (min) = 1 79 1 18 Travel Time (TO Length (ft)Slope (s) Flow Type Column Velocity Tt(min) 543 0 50 Gutter 7 1 50 6 03 I 8 0 00 0 00 8 0 00 0 00 8 0 00 0 00 Total Travel Time = 6 03 Time of Concentration (Tc) 2 yr 100 yr Total Length = 558 Tc = Ti + Tt 7 82 7 21 2 yr 100 yr Tc (min) = 7 82 7 21 Use Tc = 7 00 8 00 Intensity 2 yr 100 yr I (iph) 2 59 8 61 Area - - - - A - - - - - - Area = 29332 ft - - - - - - - - - - - - - Area = 0 67 acres Discharge (Q = C I A) - - - - - - - - - - Event C I (1ph) - - - A (acres) - - - - Q (cfs) - - - - - - 4 2 yr 0 63 2 59 0 67 1 11 100 yr 0 79 8 61 0 67 4 60 k:onciusion Time of concentrations were rounded to the nearest whole minutes All Valley pans and pipe slopes have been conservately rounded to 0 5- Tc = L/180+10 is from Urban Drainage & Flood Control District 3 4 2 Final Drainage Calcs (First Free Will Baptist) DQ Page 2 Job No 1785 01 00 Shear Engineering Corporation Designer SWT First Free Will Baptist Church Developed Conditions Design Pt al Sub basins Al 01 Rational Method All Rainfall Intensities taken from Larimer County Storm Water Management Manual Fiq 3 3 1 1 Area I Fort Collins 4/22/2003 4 03 PM Runoff Coefficients C - - - - - - - 2 yr 0 46 - - - - - - - - 100 yr 0 58 Intensity Duration Frequency - - - - - - - Time of Concentration - - - - - - - - Overland Travel Time (Ti 87*(1 1 C) L"(1/2)/S (1/3) Length = 15 00 ft Slope = 6 67 s 2 yr 100 yr C = 0 46 0 58 Ti (min) = 2 45 2 01 Travel Time (TO Length (ft)Slope (s)Flow Type Column Velocity Tt(min) 543 0 50 Gutter 7 1 50 6 03 I 8 0 00 0 00 8 0 00 0 00 8 0 00 0 00 Total Travel Time = 6 03 Time of Concentration (Tc) 2 yr 100 yr Total Length = 558 Tc = Ti + Tt 8 48 8 04 2 yr 100 yr Tc (min) = 8 48 8 04 Use Tc = 8 00 9 00 Intensity 2 yr 100 yr I (iph) 2 47 8 17 Area - - - - - - - - - - - - - - - - - A - - - Area = 37102 ft Area = 0 85 acres Discharge (Q = C I A) Q - - - - - - - - - Event C I (1ph) - - - - - - - - A (acres)Q (cfs) - - - 2 yr 0 46 2 47 0 85 0 97 100 yr 0 58 8 17 0 85 4 02 conclusion Time of concentrations were rounded to the nearest whole minutes All Valley pans and pipe slopes have been conservately rounded to 0 5- Tc = L/180+10 is from Urban Drainage & Flood Control District 3 4 2 Final Drainage Calcs (First Free Will Baptist) DQ Page 3 Job No 1785 01 00 Shear Engineering Corporation 4/23/2003 Designer SWT First Free Will Baptist Church 9 21 AM Developed Conditions Design Pt osl Sub basins 0S1 Rational Method All Rainfall Intensities taken from Larimer County Storm Water Management Manual Fig 3 3 1 1 Area I Fort Collins Runoff Coefficients C — 2 yr— 0 46 — — — — — — — — — — — — — — — 100 yr 0 58 Intensity Duration Frequency — — — — — — — Time of Concentration — — — — — — — — — — Overland Travel Time (Ti 87 (1 1 C) L�(1/2)/S (1/3) Length = 90 00 ft Slope = 1 11 s 2 yr 100 yr C = 0 46 0 58 Ti (min) = 10 97 9 00 Travel Time (Tt) Length (ft)Slope (s) Flow Type Column Velocity Tt(min) 8 0 00 0 00 I 8 0 00 0 00 8 0 00 0 00 8 0 00 0 00 Total Travel Time = 0 00 Time of Concentration (Tc) 2 yr 100 yr Total Length = 90 Tc = Ti + Tt 10 97 9 00 2 yr 100 yr Tc (min) = 10 97 9 00 Use Tc = 10 00 9 00 Intensity 2 yr 100 yr I (iph) 2 21 8 17 Area A — — — — — — — — — — Area = 14375 ft — — — — — — — — — — — — — Area = 0 33 acres Discharge (Q = C I A) Q — — — — — — — — — — Event C I (iph) — — — A (acres) — — — — — Q (cfs) — — — — — 2 yr 0 46 2 21 0 33 0 34 100 yr 0 58 8 17 0 33 1 55 Conciusion Time of concentrations were rounded to the nearest whole minutes All Valley pans and pipe slopes have been conservately rounded to 0 5- Tc = L/180+10 is from Urban Drainage & Flood Control District 3 4 2 Final Drainage Calcs (First Free Will Baptist) DQ Page 6 Job No 1785 01 00 Shear Engineering Corporation Designer SWT First Free Will Baptist Church Developed Conditions Design Pt os2 Sub basins OS2 Rational Method All Rainfall Intensities taken from Larimer County Storm Water Manaqement Manual Fiq 3 3 1 1 Area I Fort Collins 4/23/2003 9 21 AM Runoff Coefficients C — — — — — — — 2 yr 0 43 — — — — — — — — 100 yr 0 54 Intensity Duration Frequency — — — — — — — — — — — — — Time of Concentration — Overland Travel Time (T1 87*(1 1 C) L�(1/2)/S (1/3) Length = 75 00 ft Slope = 2 67 %; 2 yr 100 yr C = 0 43 0 54 Ti (min) = 7 82 6 57 Travel Time (Tt) Length (ft)Slope (s)Flow Type Column Velocity Tt (min) 120 3 75 Swale 6 2 35 0 85 I 8 0 00 0 00 8 0 00 0 00 8 0 00 0 00 Total Travel Time = 0 85 Time of Concentration (Tc) 2 yr 100 yr Total Length = 195 Tc = Ti + Tt 8 67 7 42 2 yr 100 yr Tc (min) = 8 67 7 42 Use Tc = 8 00 8 00 Intensity 2 yr 100 yr I (iph) 2 47 8 61 Area A — — — — — — — — — Area = 45738 ft — — — — — — — — — — — Area = 1 05 acres Discharge (Q = C I A) — — — — — — — — — Event C I (iph) — — — A (acres) — — — — — Q (cfs) — — — Q 2 yr 0 43 2 47 1 05 i 11 100 yr 0 54 8 61 1 05 4 86 conciusion Time of concentrations were rounded to the nearest whole minutes All Valley pans and pipe slopes have been conservately rounded to 0 5c Tc = L/180+10 is from Urban Drainage & Flood Control District 3 4 2 Final Drainage Calcs (First Free Will Baptist) DQ Page 7 4/23/2003 9 21 AM Job No 1785 01 00 Shear Engineering Corporation Designer SWT First Free Will Baptist Church Developed Conditions Design Pt os3 Sub basins OS3 Rational Method All Rainfall Intensities taken from Larimer County Storm Water Manaqement Manual Fiq 3 3 1 1 Area I Fort Collins Runoff Coefficients C — yr— —0 —20 — — — 2 — — — — — — — — 100 yr 0 25 Intensity Duration Frequency — — — — — — — Time of Concentration — — — — — — — Overland Travel Time (T1 87 (1 1 C) L (1/2)/S (1/3) Length = 60 00 ft Slope = 10 00 6 2 yr 100 yr C = 0 20 0 25 Ti (min) = 6 05 5 71 Travel Time (Tt) Length (ft)Slope (s)Flow Type Column VelocityTt(min) 543 0 50 Gutter 7 1 50 6 03 I 8 0 00 0 00 8 0 00 0 00 8 0 00 0 00 Total Travel Time = 6 03 Time of Concentration (Tc) 2 yr 100 yr Total Length = 603 Tc = Ti + Tt 12 08 11 75 2 yr 100 yr Tc (min) = 12 08 11 75 Use Tc = 12 00 12 00 Intensity 2 yr 100 yr I (1ph) 2 07 7 24 Area A - - - - - - - - - Area = 7405 ft - - - - - - - - - - - Area = 0 17 acres Discharge (Q =— C I A) 4 - - - - - - - - Event C I (iph) - - - - - - A (acres)Q (cfs) - - - - - 2 yr 0 20 2 07 0 17 0 07 100 yr 0 25 7 24 0 17 0 31 conciusion Time of concentrations were rounded to the nearest whole minutes All Valley pans and pipe slopes have been conservately rounded to 0 5- Tc = L/180+10 is from Urban Drainage & Flood Control District 3 4 2 Final Drainage Calcs (First Free Will Baptist) DQ Page 8 Job No 1785 01 00 First Free Will Baotist Church Designer SWT Shear Engineering Corporation 2/3/2003 9 00 AA! Storm Sewers First Free Will Baptist Church Worksheet for Circular Channel Project Description Project File d:\haestad\fmw\first fr.fm2 Worksheet Referred from Section V.D.1 Flow Element Circular Channel Method Manning's Formula Solve For Channel Depth Input Data Mannings Coefficient 0.012 Channel Slope 0.005400 ft/ft Diameter 15.00 in Discharge 1.44 cfs Results Depth 0.45 ft Flow Area 0.40 ft2 Wetted Perimeter 1.61 ft Top Width 1.20 ft Critical Depth 0.47 ft Percent Full 36.19 Critical Slope 0.004512 ft/ft Velocity 3.59 ft/s Velocity Head 0.20 ft Specific Energy 0.65 ft Froude Number 1.10 Maximum Discharge 5.53 cfs Full Flow Capacity 5.14 cfs Full Flow Slope 0.000423 ft/ft Flow is supercritical. Notes: This is the 15" ADS N-12 which conveys water from the outfall box to the southern side of the berm. This is the 2-yr release flow in storm sewer C. 05/20/03 FlowMaster v5.13 01:51:25 PM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1 First Free Will Baptist Church Worksheet for Circular Channel Project Description Project File d:\haestad\fmw\first fr.fm2 Worksheet Referred from Section V.D.2 Flow Element Circular Channel Method Manning's Formula Solve For Channel Depth Input Data Mannings Coefficient 0.012 Channel Slope 0.041300 ft/ft Diameter 15.00 in Discharge 7.42 cfs Results Depth 7.7 in Flow Area 0.63 ft' Wetted Perimeter 2.00 ft Top Width 1.25 ft Critical Depth 1.09 ft Percent Full 51.28 Critical Slope 0.010285 ft/ft Velocity 11.71 ft/s Velocity Head 2.13 ft Specific Energy 2.77 ft Froude Number 2.90 Maximum Discharge 15.30 cfs Full Flow Capacity 14.22 cfs Full Flow Slope 0.011243 ft/ft Flow is supercritical. Notes: This an 15" ADS N-12, which conveys runoff from the manhole to the detention pond. In the plan set, this is the lower part of Storm Sewer B. 02/07/03 FlowMaster v5.13 10:41:42 AM Haostad Methods, Inc. 37 Brookside Road Waterbury, CT 0670a (203) 755-1666 Page 1 of i First Free Will Baptist Church Worksheet for Circular Channel Project Description Project File d:\haestad\fmw\first fr.fm2 Worksheet Referred from Section V.D.3 Flow Element Circular Channel Method Manning's Formula Solve For Channel Depth Input Data Mannings Coefficient 0,013 Channel Slope 0,023700 ft/ft Diameter 15.00 in Discharge 4.02 cfs Results Depth 6.6 in Flow Area 0.52 W Wetted Perimeter 1.82 ft Top Width 1.24 ft Critical Depth 0.81 ft Percent Full 44.25 Critical Slope 0.006796 ft/ft Velocity 7.67 ft/s Velocity Head 0.92 ft Specific Energy 1.47 ft Froude Number 2.08 Maximum Discharge 10.70 cfs Full Flow Capacity 9.94 cfs Full Flow Slope 0.003873 ft/ft Flow is supercritical. Notes: Minor -basin At was delineated for the purpose of determining the depth of flow within this culvert. This is a 15" RCP located underneath the access between the property and West Trilby Road. This pipe will stay in place for the ultimate condition. In the plan set, this is storm sewer A. 04/23/03 FlowMaster v5.13 01:28.23 PM Haostad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1 First Free Will Baptist Church Worksheet for Circular Channel Project Description Project File d:\haestad\fmw\first fr.fm2 Worksheet Referred from Section V.D.4 Flow Element Circular Channel Method Manning's Formula Solve For Channel Depth Input Data Mannings Coefficient 0.013 Channel Slope 0.029600 ft/ft Diameter 15.00 in Discharge 4.60 cfs Results Depth 6.7 in Flow Area 0.53 ft' Wetted Perimeter 1.83 ft Top Width 1.24 ft Critical Depth 0.87 ft Percent Full 44.84 Critical Slope 0.007356 ft/ft Velocity 8.63 ft/s Velocity Head 1.16 ft Specific Energy 1.72 ft Froude Number 2.32 Maximum Discharge 11.95 cfs Full Flow Capacity 11.11 cfs Full Flow Slope 0.005071 ft/ft Flow is supercritical. Notes: This is a 15" RCP located along the northside of West Trilby Road. For interim condition only, this will be placed until West Trilby Road is developed. 04/23/03 FlowMaster v5.13 01:29:09 PM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1 Job No 1785 01 00 First Free Will Baptist Church Designer SWT Shear Engineering Corporation Swales 4/23/2003 1 10 PM First Free Will Baptist Church Worksheet for Triangular Channel Project Description Project File d:\haestad\fmw\first fr.fm2 Worksheet Swale Section Z-Z Flow Element Triangular Channel Method Manning's Formula Solve For Channel Depth Input Data Mannings Coefficient 0.032 Channel Slope 0.029630 ft/ft Left Side Slope 2.000000 H : V Right Side Slope 2.000000 H : V Discharge 22.29 cfs Results Depth 1.39 ft Flow Area 3.84 ft' Wetted Perimeter 6.19 ft Top Width 5.54 fit Critical Depth 1.51 ft Critical Slope 0.019037 ft/ft Velocity 5.81 fus Velocity Head 0.52 It Specific Energy 1.91 ft Froude Number 1.23 Flow is supercritical. 04/23/03 FlowMaster v5.13 07:36:50 AM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1 Job No 1785 01 00 First Free Will Baptist Church Designer SWT Shear Engineering Corpora ion 2/3/2003 8 58 AM Riprap 2/4/2003 Shear Engineering Corporation Riprap Designer: SWT First Free Will Baptist Church Riprap-circular Sizing of Riprap Apron for Circular pipe a Storm Line outlet Notes: This is located at the 15" ADS N-12 which outfalls from the manhole into the detention pond Pipe and Plow Data Pipe Diam Area R Slope Capacity Q100 cfs Type Dc ft sf ft ft/ft C-Factor cfs 7.421 ADSI 1.25 1 1.23 1 3.93 1 0.0362 1 69.98 13.31 Flow Depth r - x '- x/r Yn 0.5*D r-Yh (7) Theta Theta Area Perim ft ft ft deg. rad. sf ft 6.6669 1 0.63 1 -0.04 1 -0.07 1 187.68 3.28 0.67 2.05 Top R C Qd Delta Vel Froude Vel Width n - # head T 0.012 ft ft cfs cfs fps ft 1.247 10.3253 1 39.00 1 7.42 1 0.00 1 11.14 1 2.6885 1.93 TEP I moolflea Flow Deotn It supercr t ca ow, & < tull Supercritical flow Da=1/2(DC+Yn)= 0.96 feet STEP 2 Determine Froude Parameter FPx - integer (FP-6) Q/Da"2.5 - 8.25 FPx = 2.00 STEP 3 Determine Type of Riprap Flow depth macro will set Yt to a value which makes Yt/D - 0.40 if Yt unknown or jump expected. Designer can change Yt if known Yt (ft) Yt/Da Q/Da"1.5 Solving Equation MD-18 0.50 0.40 7.91 D50 = 6.554 inches D50 - 9.00 inches - bury riprap From Figure MD-21 Use Class L Riprap STEP 4 Determine Expansion Factor From Figure MD-23 Q/D-2.5 Interpolation of 1/2Tan(Theta) Yt/D 6.00 6.00 6.00 0.39 1.75 1.75 1.75 Note that the maximum 0.4000 1.83 1.83 1.83 value of Q/D^2.5 on 0.40 1.83 1.93 1.83 figure MD-23 = 6 1/2TAN(THETA) = 1.83 STEP 5 Determine Required•Length of Protection Allowable Velocity =(Va) 5.50 fps At = Q/Va = 1.35 sf L=(1/2TAN(THETA))*(At/Yt-Da)= 3.18 ft Minimum Length= 3D = 3.75 ft Max Length = 1OD+(FPx*0.25*D)= 13.13 ft Conclude: Riprap Geometry Apron Length D50 FES width ft inches width ft ft 3.75 9.00 3.50 5.00 Page 1 of 2 Governs 2/4/2003 Shear Engineering Corporation Riprap Designer: S'AT First Free Will Baptist Church Riprap-circular Sizing of Riprap Apron for Circular pipe ® Storm Line outlet Notes: This is for the interim condition. The will located at the outfall for the 4' channel in the SE corner Pipe and Flow Data Diam Dc Area R Slope Capacity Q100 cfs Pipe Type ft sf ft ft/ft C-Factor cfs 6.261 ADSI 1.25 1 1.23 3.93 1 0.0050 69.98 4.95 Flow Depth r - x - x/r Yn 0.5*D r-Yh (7) Theta Theta Area Perim ft ft ft deg. rad. sf ft 0.7567 0.63 -0.13 1 -0.21 204.33 3.57 0.78 2.23 Top R - C Qd Delta Vel Froude Vel Width n = # head T 0.012 ft ft cfs cfs fps ft 1.222 0.3486 47.66 3.37 -2.89 4.34 0.9589 0.29 TEP ModifiedFlow Dent sunercr t ca ow & < u Subcritical flow Dc= 1.25 feet STEP 2 Determine Froude Parameter FPx = integer (FP-6) Q/Dc^2.5 3.58 FPx = 0.00 STEP 3 Determine Type of Riprap Flow depth macro will set Yt to a value which makes Yt/D - 0.40 if Yt unknown or jump expected. Designer can change Yt if known Yt (ft) Yt/Dc Q/Dc% .5 Solving Equation MD-18 1.00 0.80 4.48 D50 - 1.616 inches D50 - 9.00 inches - bury riprap From Figure MD-21 Use Class L Riprap STEP 4 Determine Expansion Factor From Figure MD-23 QW2.5 Interpolation of 1/2Tan(Theta) Yt/D 3.00 3.58 4.00 0.39 4.2.5 3.74 3.36 0.8000 6.67 4.84 3.54 0.80 6.67 4.84 3.54 1/2TAN(THETA) = 4.84 STEP 5 Determine Required Length of Protection Allowable Velocity -(Va) 5.50 fps At - Q/Va - 1.14 sf L=(1/2TAN(THETA))*(At/Yt-Da)= -0.54 ft Minimum Length= 3D - 3.75 ft Max Length = lOD+(FPx*0.25*D)= 12.50 ft Conclude: Riprap Geometry Apron D50 FES width width Length ft inches ft ft 3.75 9.00 3.50 5.00 Page 2 of 2 Governs Job No 1785 01 00 First Free Will Baptist Church Designer SWT Shear Engineering Corporation Detention 4/23/2003 7 52 AM Job 1785 01 00 Shear EngineL ig Corporation Designer SWT First Free Will Baptist Church Detention Pond Summary Detention Pond Statistics 100 year Water Surface Elevation 5054 36 ft Top of Berm Elevation 5055 50 ft 100 yr Volume required 0 97 ac ft 100 yr Volume available 1 82 ac ft Release rate 1 44 cfs Water Quality Control Pond Statistics Water Surface Elevation 5052 89 ft Volume 0 12 ac ft Release rate 0 03 cfs Note Water Quality statistics are incorporated into Detention Statistics Final Drainage Calcs (First Free Will Baptist) QSum Page 1 of 8 5 /2003 1 20 PM Job ..-. 1785-01-00 Shear Engines_ .g Corporation 5, ./2003 Designer: SWT First Free Will Baptist Church 10:34 AM Developed Conditions - Basin Basin Detention Pond 2-yr Storm 100-yr Ground Cover Area (ft') Area (ac) Percent Area C Weighted C Weighted C Sub -basin A 194277.60 4.46 86.94% 0.54 0.47 0.59 Sub -basin B 29185.20 0.67 13.06% 0.79 0.10 0.13 223462.80 5.13 11 0.57 0.72 Final Drainage Calcs (First Free Will Baptist) Page 1 of 1 C Job No. 1785-01-00 Shear Engineering Corporation 5/19/2003 Designer: SWT First Free Will Baptist Church 10:16 AM 100-year Storm Detention Volume Calculations 10aKV4tl07i :?feiva�s • Note: The cummuiat ve runoff method s used, according to Larimer County.. - Storm Water Management Manual (Sec. 9. .3.3) Cumulative Runoff Method for Sizing Detention Ponds Detention Pond 1 Design Point A Runoff Coefficient 0.72 Area -..-.5.00 acres Design Storm -100 year Release Rate 1.44 cfs Inflow Inflow Release Storage Storage Peak Time Intensity Rate Volume Volume Volume Volume Storage min iph cfs cf cf cf ac-ft 5 9.95 35.58 10675 431 10244 0.24 10 7.72 27.61 16565 863 15702 0.36 15 6.52 23.32 20985 1294 19691 0.45 20 5.60 20.03 24032 1726 22306 0.51 25 4.98 17.81 26714 2157 24557 0.56 30 4.52 16.16 29096 2589 265D7 0.61 35 4.08 14.59 30641 3020 27621 0.63 40 3.74 13.37 32100 3451 28649 0.66 45 3.46 12.37 33409 3883 29526 0.68 50 3.23 11.55 34653 4314 30339 0.70 55 3.03 10.84 35758 4746 31013 0.71 60 2.86 10.23 36821 5177 31643 0.73 65 2.72 9.73 37936 5608 32328 0.74 70 2.59 9.26 38902 6040 32862 0.75 75 2.48 8.87 39910 6471 33439 0.77 80 2.38 8.51 40854 6903 33952 0.78 85 2.29 8.19 41766 7334 34432 0.79 90 2.21 7.90 42678 7766 34913 0.80 95 2.13 7.62 43419 8197 35222 6.81 100 2.06 7.37 44202 8628 35573 0.82 105 2.00 7.15 45060 9060 36000 0.83 110 1.94 6.94 45790 9491 36298 0.83 115 1.89 6.76 46637 9923 36714 0.84 120 1.84 6.58 47377 10354 37023 0.85 Detention Volume Required 37023 cf Detention Volume Required 0.85 ac-ft Total Volume Required for Detention Pond 1 100-yr Storm cf ac-ft Flood Volume 37023.32 0.85 WQCV 5029.59 0.12 Total 42053 0.97 Final Drainage Calce (First Free Will Baptist) CRunoff Page 1 Project No.: 1785-01-00 Shear Engineering Corporation Designer: SWT First Free Will Baptist Church 5/19/2003 10:16 AM 100-yr Water Surtace Elevation Pond Detention Pond Criteria Store difference between developed and historic minor storms Larger storms to be stored until released by emergency overflow Invert 5051.92 ft First Even Contour 5052.00 ft Increment 1:00 ft Top Elevation 5055.50 ft Pond Detention Pond Volume Stage E evat-ion Area (VI) ft ft sf cf Cumulative Volume cf ac-ft Req Volume cf 0.00 5051.92 0 0E794445 0.00 42053 0.08 5052.00 127 50.00 42053 0.58 5052.50 4669 1199 0.03 42053 1.08 5053.00 114724 4848 0.14 42053 1.58 5053.50 26603 - 10332 0.38 42053 2.08 5054.00 30415 14255 0.70 42053 3.08 5055.00 33223 31819 1.43 42053 3.58 5055.50 34727 16987 1.82 42053 100-yr Required Volume 42053 cf Required WSEL 5054.36 ft Freeboard 114 ft WS Area 47005 sf= 1.08 acres Tract Area 26603 sf= 0.61 acres Tract area is assumed to be the area at the top of the pond until a boundary is placed around the pond. The boundary will most likely create a larger tract around the pond Final Drainage Calcs (First Free Will Baptist) Page 1 Proj,-t No.: 1785-01-00 Shear Enginee_-ng Corporation Designer: SWT First Free Will Baptist Church Detention Pond Stage Storage Curve 5/_./2003 10:30 AM 5056.00 5055.50 - --- — + -- — i 5055.00 5054.50 — — -- - w 5054.00 -= 5053.50 5053.00 -- - • - — -- 5052.50 . - --- — 5052.00 ---- - — ---- --- — 5051.50 0 10000 20000 30000 40000 50000 60000 70000 80000 90000 Storage (cf) —+ — Storage —=— Req'd Volume SStorage Chart 1 Page 1 Project No. 1785-01-00 Shear Engineering Corporation By: SWT First Free Will Baptist Church Emergency Overflow Weir Calculation BROADCRESTED WEIR FLOW EQUATION : CWLH"3/2 PRIMARY WEIR INFO UPPER WEIR INV. (ft) = 5054.36 UPPER WEIR LENGTH(ft) = 12.00 UPPER WEIR COEF. (Cw) = 2.60 TOP OF INFLOW = 5055.16 INIT. DELTA (ft) = 0.80 DELTA HEAD (ft) = 0.80 PRIMARY WEIR TARGET FLOW = 22.29 cfs *Note: This is assuming that a 100-yr flow passing into the box. This will only happen if the detention pond is full from a previous 100-yr storm occuring previously. Final Drainage Calcs (First Free Will Baptist) Page 1 5/19/2003 10:16 AM Job No 1785 01 00 First Free Will Baptist Church Designer SWT Shear Engineering Corporation 2/3/2003 10 11 AIM Orifice Release Job �. 1785-01-00 Shear Engine. ng Corporation 5. /2003 Designer: SWT First Free Will Baptist Church 12:36 PM Orifice Release for Outlet Structure Detention Pond Determine Req'd Orifice Q= CA(2gH)"0.5 A = Q/(C(29H)"0.5 H (ft) _ <2.20.. C = 0.65 Q (cfs) 11.44. A (sf) = 0.19 R (ft) = 0.244 D (ft) = 0.487 Use 0.487 ft diameter orifice Lower Orifice:: uata. Diam. 0.49 ft Invert 5051.92'--ft Top of Orifice 5052.41i.ft Coefficient 0.65_', Final Drainage Calcs (First Free Will Baptist) Orifice = 5 7/8 linches Design Release Req'( Storm Rate WSEL yr cfs ft '.:100 1-.44 5054. Top of Berm ft 3055.50 Job No 1785 01 00 First Free Will Baptist Church Designer SWT Shear Engineering Corporation 5/20/2003 1 03 PM Weir Project No. 1785-01-00 Shear Engineering Corporation By: SWT First Free Will Baptist Church 5/20/2003 12:54 PM Emergency Overflow Weir Calculation BROADCRESTED WEIR FLOW EQUATION : CwLH"3/2 PRIMARY WEIR INFO UPPER WEIR INV. (ft) = 5055.50 UPPER WEIR LENGTH(ft) = 323.48 UPPER WEIR COEF. (Cw) 2.60 TOP OF INFLOW = 5055.59 INIT. DELTA (ft) = 0.09 DELTA HEAD (ft) 0.09 PRIMARY WEIR TARGET FLOW = 22.29 cfs *Note: This is assuming that a 100-yr flow passing into the box. This will only happen if the detention pond is full from a previous 100-yr storm occuring previously. Final Drainage Calcs (First Free Will Baptist) Page 1 Project NO 1785 01 00 By SWT Shear Engineering Corporation 4/23/2003 8 06 AM Water Quality Volume Calculations Job No 1785 01 00 Shear Engineering Corporation Designer SWT First Free Will Baptist Church 5/19/2003 10 00 AM DETERMINATION OF WATER QUALITY CAPTURE VOLUME FOR POND 1 AREA = 5 51 acres Using Figure SQ 5 Urban Drainage And Flood Control District Assumptions One Single Family Dwelling Unit per Acre 3000 sq ft homes OVERALL PERCENT IMPERVIOUS 50 00 PERCENT TYPE OF POND (RETENTION OR DETENTION) Detention SELECT 40 00 HOUR BRIM FULL VOLUME DRAIN TIME USES 40 HOUR FOR DETENTION PONDS USES 12 HOUR FOR RETENTION PONDS FROM FIGURE 5 1 REQUIRED STORAGE WATERSHED INCHES OF RUNOFF= 0 2096 WATER QUALITY CAPTURE VOLUME (WQC(REQUIRED STORAGE/12) AREA WATER QUALITY CAPTURE VOLUME (WQCV) = 0 10 AF 4191 cf WQCV SAFETY FACTOR OF 1 2 = 5029 59 cf Release Rate = 0 0349 cfs Conclude Design pond to have at this least 5030 cf of storage Install water quality outlet structure FFWB WQCV WQCV Page 1 of 4 Job No 1785 01 00 Shear Engineering Corporation Designer SWT First Free Will Baptist Church 5/19/2003 4 02 PM Average Area End Method for Determining Volumes Pond 1 Pond located in the southwest corner of the property Invert 5051 92 ft Increment 1 00 ft First Even Contour 5052 00 ft Too of berm elev 5056 00 Elev ft Stage ft Depth d ft Area sf Increment Volume cf Cum Volume cf Cum Volume ac ft 5051 92 0 00 0 0 0 00 0 0 5052 00 0 08 0 08 127 5 07 5 0 00 5052 50 0 58 0 50 4669 1199 08 1204 0 03 5053 00 1 08 0 50 14724 4848 37 6053 0 14 5053 50 1 58 0 50 26603 10331 81 16384 0 38 5054 00 2 08 0 50 30415 14254 65 30639 0 70 5055 00 3 08 1 00 33223 31818 96 62458 1 43 5055 50 3 58 0 50 34727 16987 43 79445 1 82 Determine WSEL for WQCV Req d Volume 5030 cf WSEL is below 5055 50 ft Req d WSEL = 5052 89 ft Elev Cum Freeboard = 3 11 ft Volume Error Messages ft cf 5052 89 5030 Freeboard ok 5053 00 6053 FFWB WQCV Stage Storage Job No 1785 01 00 Shear Engineering Corporation Designer SWT First Free Will Baptist Church 5/19/2003 4 01 PM Water Quality Outlet Structure Water Quality in Detention Pond 1 WQCV = 0 10 AF Required WSEL = 5052 89 ft Top of Pond 5056 00 ft Invert = 5051 92 ft Head (Dwq) = 0 97 ft From Figure 5 UDFCD Drainage Criteria Manual (V 3) Use 2 rows 2 columns Note The top row has only one orifice Must Drain 5030 cf Row 1 Q 0 0263 cfs in 40 00 hours Row 2 Q 0 0088 cfs Required Q 0 035 cfs Provided Q 0 035 cfs Orifice Equation A = Q/(C(2gH) 5) Row 1 Row 2 Elevation 5051 94 ft Elevation 5052 27 ft hole Dia 11/16 in hole Dia 5/8 in A= 0 37 inA2 A= 0 31 in 2 A= 0 00 ft 2 A= 0 00 ft 2 C = 0 65 C = 0 65 g = 32 20 ft/s"2 g = 32 20 ft/s 2 H = 0 95 ft H = 0 62 ft Q = 0 013 cfs Q = 0 009 cfs Notes Minimum Spacing between columns is 3 inches Minimum Spacing between rows is 4 inches Provided discharge is slightly less than required discharge this is acceptable According to Drainage Criteria Manual (V 3) Figure 5 32nd inch is the tolorence allowed Discharge calculations are only calculating one column FFWB WQCV WQoutlet Pro3ect No 1785 01 00 Shear Engineering Coporation By SWT First Free Will Baptist Church 5/19/2003 3 59 PM Well -Screen Type Trash Rack Specifications Performation Diameter Distance between rows Distance between columns Width of Concrete Opening Width of Trash Rack From Table 6a 2 5/8 inches 4 inches 3 inches 6 inches 6 inches Max Width Opening Less Than 9 Screen #93 VEE Wire Slot Opening 0 139 inches Support Rod Type #156 VEE Support Rod 0 C Spacing 0 75 inches Total Screen Thickness 0 31 feet Carbon Steel Frame Type 3/8 x 1 0 flat bar Notes From Table 6a 1 Urban Storm Drainage Criteria Manual (BMP) FFWB WQCV FFWB WQCV well Screen Well Screen Final Drainage and Erosion Control Report for First Free«ill Baptist Church Project No 1785 01 00 Appendix II Supporttng documents uaphs, tables, exlubtts, etc Figure 3 1 Rainfall Intensity Duration Frequency Curve (City of Fort Collins SDDCCS) City of Fort Collins Rainfall Intensity Duration Frequency Table City of Fort Collins Stormwater Basins (ham //fcgov com/stormwater/masterplan oho) Figure 4 Orifice Details for Draining WQCV (USDCM Vol 3) Figure 5 WQCV Outlet Orifice Perforation Sizing (USDCM Vol 3) N OF FORT COLLINS yrxr 5 ilurntua trBactnr Tj C cci, Bavn G+ccnb+�a t:rcrfl ccr.�yin n � "' t OldTo%,.n4011h0a 0 s n T 3 0 } } k V7 Ulno bY�A fd Tov n E �n } o a IT t u 1' Imp cr-i orl 13 m �$ Y s}^t}fn�FOrack�z�i+n P'aattall} B i 1 � J ,t ux>ti adwf�t� TdtClctlan-!5/t�i C` cc), 6 ¢ j � �osstt Crack Basn�} f � ; SITE (r-19S7- FnEr_ w11-1- C1APTiST C11vncy) Orifice Perforation Details Structural Steel Cho at Fo med I to C t T Span Yrdth Of Stru to e Fg See F gures 6—a 6—b A� WPI t = We VIC + 6 Inches (minimum) (see below) 01 0 10 of O to 4 H v B B of O to Permanent O—I f Water Surface 0-7 01 I ly 2-4�—I M` M mm 4 O 0 1 1 Circular Openings We Obtained From Table 6a-1 Rectangular Openings VIC = (Width of Rectangular Perforation W) + 12 Rectangular Openings flop a (see Figure 6—b) Obtained From Table 6b-1 S S fg 5 Fg 5 W O o O O o o {L L O O O 000 O O O O o 000 O o O O O O 000 It O Iff— Example Perforation Patterns Note The goal in des ning the outlet is to minimize the number of columns of perforations that will droin the WQCVig in the d sired time Do not however increase the diameter of circular perforations or the height of the rectangular perforations beyond 2 inches Use the allowed perforation shop and configurations shown above along with Figure 5 to determine the pattern that provides an area per ro%/ closest to that required without exceeding it Urban Drainag and Figure Flood Control District Orifice Details for Drainage Criteria Manual (V 3) Draining WQCV Fi D t 3 dg Orifice Plate Perforation Slzlnq Circular Perforation Sizing Chart may be applied to orifice plate or v rt cal pipe outlet H 1 0 H 1 0 ( ) I M Sc ( ) A p R ( q 1) .1 =2 1 3 1 4 0 250 1 005 010 1 015 I 5 0313 2 008 015 023 3 8 0 375 2 Oil 0 22 0 33 7/16 0 438 2 015 030 045 1 /2 0 500 2 020 039 059 9/16 0 563 3 025 050 075 5/8 0 625 3 031 061 092 11 /16 0 688 3 0 37 074 1 11 3 4 0 750 3 044 088 1 33 13 I6 0 813 3 052 104 1 56 7 8 087 3 060 1 20 1 80 15 1 0 938 3 069 1 38 I 207 1 1 000 4 079 1 57 236 1 1 16 1 0 3 4 089 1 77 266 1 1 8 1 125 4 099 1 99 298 1 3 16 1 188 4 1 11 222 332 1 1 4 1 250 4 1 23 245 368 1 5/16 1 1313 4 135 271 406 1 J 8 1 375 4 1 48 297 445 1 7 16 1 438 4 1 62 325 487 1 1 2 1 500 4 1 77 353 530 1 9 16 1 563 4 192 383 575 1 5 8 1 625 4 207 415 622 1 11 I6 1 688 4 224 447 671 1 3 4 1 750 4 2 41 481 722 1 13 16 1813 4 258 516 774 1 7 8 1 875 4 276 552 828 1 15 16 1 938 4 2 95 590 884 2 2000 4 J 14 628 942 -Nmb f I fp f t M m m ! I pl t th 1/4 5/16 3/8 D g m y t p I t t th t 32 d h t b t h th q d f d Rectangular Perforation Sizing Only one column of rectangular perforations allowed Rectangular Height = 2 Inches Rectangular �Ikith (inches) = Required Area per Ro i (sq in) 2 Urban Drainage and Flood Control Distric Drainage Criteria f tanual (V 3) rA Dtt d 9 Rectangular Hole Width Min Steel Thickness 5 1 4 6 1 e 7 5/32 8 5/16 9 11 /32 10 3/8 >10 1/2 Figure 5 MCV Outlet Orifice Perforation Sizing Final Drainage and Erosion Control Report for First Free �N ill Baptist Church Project No 1785 01 00 Appendix III Erosion Control Erosion Control Deposit Letter from Shear Engineering Corporation Rainfall Performance Standard Evaluation Effective Calculations Sub basin A Effective Calculations Sub basin B Construction Sequence Project No 1783-01 00 Fcbniiry 6 2003 Re Erosion Control Cost Estiniltc First Free Will Blptist, Fort Collins Color ido 1 According to current City of Fort Collins policy the erosion control security deposit is figured based on the larger amount of 1 5 times the estimated cost of installing the approved erosion control measures or 1 5 times the cost to re vegetate the anticipated area to be disturbed by construction activity a Based on current unit price data provided by a local erosion control company the cost to install the proposed erosion control measures is approximately $1978 00 As per City requirements 1 5 times the cost to install the erosion control measures is $2817 00 b Based on current unit price data obtained from the City of Fort Collins Stormwater and based on an actual anticipated net affected area which will be disturbed by construction activity (approximately 5 00 acres) we estimate that the cost to re vegetate the disturbed area will be $3275 00 ($655 00 per acre x 5 00 acres) As per City requirements 1 5 times the cost to revegetate the disturbed area is $4912 50 CONCLUSION The erosion control security deposit amount required for Old Town North shall be $4912 50 If you have any questions please contact me at 226 5334 Sincerely Seth W Tourney E I Shear Engineering Corporation P-ige 2 J J 1785 01 00 Shear Eng ing Corporation 5/2003 Designer SWT First Free Will Baptist Church 4 20 PM RAPT TALL PERTORNIANCE STANDARD EVALUATION PROTECT First Free Will Baptist Church STANDARD FORM A Developed hro i i rty Sub blsin Zone As I-sb (1c) (ft) Lb N (feet) Sb P N N A Mo er ite 5 51 S» 080 4590 4 41 B Moderate 067 »8 067 374 045 Tota s 6 18 803 079 LINEAR INTERPOLATION If slope exceeds 5 0 must insert performince stlndlyds m1nu111y 2 SLOPE 3 LENGTH 0 50 079 1 00 800 727 7579 78 1 803 19 75 79 900 727 75 84 782 CONCLUDE PERFORMANTCE STANDARD = 7S797a Overall Effectivness of Erosion Control Plan must exceed this amount Performance Standard Calcs Performance Page 1 of 1 1785 01 00 Shear Enginep-ing Corporation 9/5/2003 D ar SWT First Free Baptist Church 21 PM STANDARD FORM B EROSION1 METHOD VALUE VALUE Roughened Ground 100 090 Silt Fence 1 00 050 H-ivb,iles 100 080 Asph'ilt concrete 001 100 Temporin Vegetation 045 100 Gra%el Inlet Filters 100 080 MAJOR PS SUB AREA A*EFF CALCULATIONS BASIN / BASIN icre AREA C P ALL7> 7l / A DDI Rough 1 DVicres 1 liitbales 0 50 7C FFS— 100 080 Silt Fen 251 icres 100 0 D0 EQUATIONS Asph ilt 100 -icres 001 100 C = WEIGHTED AVG OF C Y AREA Check 551 P= (WEIGHTED AVG OF P Y AREA) X P C= 08203 EFF = (1 P Y C) Y 100 P = 02907 Are-i * EIIectncness = 4 20 EFF 76 15/ ovi ref ectn eness = 420 Tovil Are 1 > 51 icres O%cr-ill Lflccli%cness 76 1D/ > 75 79/ Conclude Erosion Control Pl in is cQectn e Performance Standard Calcs ecr v-npss Page 1 of 2 J 1 1755 01 00 Shear EngineF-ing Corporation ^/5/2003 1 er SWT First Free Baptist Church 21 PM STANDARD FORM B --EROSION CZFACTOR P FACTOR COM2v[ENT METHOD VALUE VALUE Roughened Ground 100 090 Silt Fence 1 00 050 Hi)b,iles 1 00 080 Aspti,ilt concrete 001 100 Tempor,iry Vegetition 04.) 1 00 Gr1N el Inlet Filters 100 080 MAJOR-- P B AREA A BASIN / BASIN icre AREA C P ALL 7.) 7) 067 RougFi 025 icres 1 lilvbales acres 100 080 Silt Fen acres 100 050 EQUATIONS Asplillt 0 42 acres 001 1 00 C = WEIGHTED AVG OF C X AREA Check 067 P= (WEIGHTED AVG OF P K AREA) X P C= 0.)794 EFF=(1 PXC)X100 P= 03851 Area * Effectiveness = 057 EFF 85 39°/ 0t1 ref ecin eness 0 D7 Tot t rea 0 67 icres Ovcr-ill C[fecln cness 85 .�9 / > 7� 79 / Conclude Erosion Control Pl in is effective Performance Standard Calcs e- veresG Page 2 of 2 CONSTRUCTION SEQUENCE PROJECT First Free Will Baptist Church STANDARD FORM C SEQUENCE FOR 2003 2004 ONLY COMPLETED BY SWT/Shear Engineering Corp Indicate by use of a bar line or s)mbols when erosion control measures will be uistalled Major modifications to an appro,ed schedule may require submittmg a neii schedule for appro,,al by the City Engineer Year 03 Montli M A M J J A S O N D OVERLOT GRADING *** *** WIND EROSION CONTROL Soil Rouolienmg *** Penmeter Barrier Additional Barriers Veget-itne Methods Sod Sealant Other RAINFALL EROSION CONTROL STRUCTURAL SedimentTrapBasin *** *** Inlet Filters Strait Barriers Silt Fence Barriers *** *** Sand Baos Bare Soil Preparation Contour Furroiis Terricuio Asplialt/Concrete Paving Oilier %EGFTATIVE Pcrmvi nt Seed Plantino Mulchuio/Scalant feniporar) Seed Plantinb Sod Installation Nett os/M-its/Bl-inkets Oth r STRUCTURES INSTALLED BY First Free Will Baptist Church MAI\TAINED BY First Free Will Baptist Church VEGETA I ION/MULCMNG CONTRACTOR First Free Will Baptist Church DATE PREPARED 02/06/03 DATE SUBMITTED 02/07/03 Al PROVED BY THE CITY OF FORT COLLINS ON Final Drainage and Erosion Control Report for First Free Will Baptist Church Project No 1785 01 00 Appendix IV Stuffer Envelope Historic Drainage Plan Drainage and Erosion Control Plan Project No: 1785-01-00 Shear Engineering Corporation 4/23/2003 By: SWT 8:06 AM Water Quality Volume Calculations Job No. 1785-01-00 Shear Engineering Corporation Designer: SWT First Free Will Baptist Church 5/19/2003 10:00 AM DETERMINATION OF WATER QUALITY CAPTURE VOLUME FOR POND 1 AREA = 5.51 acres Using Figure SQ-5, Urban Drainage And Flood Control District Assumptions: One Single Family Dwelling Unit per Acre 3000 sq. ft homes OVERALL PERCENT IMPERVIOUS: 50.00 PERCENT TYPE OF POND (RETENTION OR DETENTION) Detention SELECT 40.00 HOUR BRIM FULL VOLUME DRAIN TIME USES 40 HOUR FOR DETENTION PONDS USES 12 HOUR FOR RETENTION PONDS FROM FIGURE 5-1 REQUIRED STORAGE WATERSHED INCHES OF RUNOFF= 0.2096 WATER QUALITY CAPTURE VOLUME (WQC(REQUIRED STORAGE/12)*AREA WATER QUALITY CAPTURE VOLUME (WQCV) = 0.10 AP 4191 cf WQCV * SAFETY FACTOR OF 1.2 = 5029.59 cf Release Rate = 0.0349 cfs Conclude Design pond to have at this least 5030 cf of storage Install water quality outlet structure FFWB-WQCV WQCV Page 1 of 4 f Job No. 1785-01-00 Designer: SWT Shear Engineering Corporation First Free Will Baptist Church 5/19/2003 4:02 PM Average Area End Method for Determining Volumes Pond 1 Pond located in the southwest Invert 5051.92 ft Increment 1.00 ft First Even Contour 5052.00 ft Top of berm elev. 5056.00 corner of the property Elev. ft Stage Depth Increment Cum. Cum. d Area Volume Volume Volume ft ft sf cf cf ac-ft 5051.92 0.00 0 0 0.00 0 0 5052.00 0.08 0.08 127 5.07 5 0.00 5052.50 0.58 0.50 4669 1199.08 1204 0.03 5053.00 1.08 0.50 14724 4848.37 6053 0.14 5053.50 1.58 0.50 26603 10331.81 16384 0.38 5054.00 2.08 0.50 30415 14254.65 30639 0.70 5055.00 3.08 1.00 33223 31818.96 62458 1.43 5055.50 3.58 0.50 34727 16987.43 79445 1.82 Req'd Volume WSEL is below Elev Cum Volume ft cf 5052.89 5030 5053.00 6053 5030 cf 5055.50 ft - Req'd WSEL = Freeboard = Error Messages Freeboard ok 5052.89 ft 3.11 ft FFWB-WQCV Stage Storage Sob No. 1785-01-00 Shear Engineering Corporation Designer: SWT First Free Will Baptist Church 5/19/2003 4:01 PM Water Quality Outlet Structure Water Quality in Detention Pond 1 WQCV 0.10 AF Required WSEL 5052.89 ft Top of Pond 5056.00 ft Invert = 5051.92 ft Head (Dwq) - 0.97 ft From Figure 5 UDFCD - Drainage Criteria Manual (V.3) Use 2 rows 2 columns *Note: The top row has only one orifice. Must Drain 5030 cf in 40.00 hours Required Q 0.035 cfs Orifice Equation: A = Q/(C(2gH)".5) Row 1 Q 0.0263 cfs Row 2 Q 0.0088 cfs Provided Q 0.035 cfs Row 1 Row 2 Elevation 5051.94 ft Elevation 5052.27 ft hole Dia. 11/16 in hole Dia. 5/8 in A = 0.37 in"2 A = 0.31 in"2 A = 0.00 ft"2 A = 0.00 ft"2 C = 0.65 C = 0.65 g 32.20 ft/SA2 g = 32.20 ft/s"2 H = 0.95 ft H = 0.62 ft Q = 0.013 cfs Q = 0.009 cfs Notes: Minimum Spacing between columns is 3 inches. Minimum Spacing between rows is 4 inches. Provided discharge is slightly less than required discharge, this is acceptable. According to Drainage Criteria Manual (V.3) Figure 5, 32nd inch is the tolorence allowed. Discharge calculations are only calculating one column. FFWB-WQCV WQoutlet Project No: 1785-01-00 Shear Engineering Coporation By; SWT First Free Will Baptist Church 5/19/2003 3:59 PM Well -Screen Type Trash Rack Specifications Performation Diameter 5/8) inches Distance between rows 4= inches Distance between columns 3-..'inches Width of Concrete Opening 6- inches Width of Trash Rack 6 inches From Table 6a-2: Max. Width Opening Less Than 9" Screen #93 VEE Wire Slot Opening 0.13911 inches Support Rod Type #156 VEE Support Rod, O.C. Spacing 0.75inches Total Screen Thickness '0.'31_,feet Carbon Steel Frame Type 3/81, x 1.0" fiat bar Notes: * From Table 6a-1 Urban Storm Drainage Criteria Manual (BMP) FFWB-WQCV FFWB-WQCV Well -Screen Well -Screen Final Drainage and Erosion Control Report for First Freewill Baptist Church Project No. 1785-01-00 Appendix II Supporting documents graphs tables exhibits, etc. Figure 3-1: Rainfall Intensity -Duration -Frequency Curve, (City of Fort Collins SDDCCS) City of Fort Collins Rainfall Intensity -Duration -Frequency Table City of Fort Collins Stormwater Basins (ham•//fcpov com/stormwater/masteroIan.ohp) Figure 4: Orifice Details for Draining WQCV (USDCM Vol. 3) Figure 5: WQCV Outlet Orifice Perforation Sizing (USDCM Vol. 3) N CITY OF FORT COLLINS t .CL]rmwnf�r Rnrr'nc S1-7E (FIRST FYKEE W�I-L OAPTrST cllvncy) Orifice Perforation Details A� Wplate = Wcanc + 6 inches (minimum) Structural Steel Channel Formed Into Concrete, To WC.. (see below) Span Width Of Structure. See Figures 6—a• 6-1b 01 0 1 0 oI O Io 4• I g g a[ O I o Permanent Q—I Water Surface OI I 12, - 2-4. L M. Minimum a o 1 0 1 1 A Circular Openings: Wcono.Obtained From Table 6a-1 Rectangular Openings: YlCena. = (Width of Rectangular Perforation W) + 12" Rectangular Openings: Wopenin9 (see Figure 6-b) Obtained From Table 6b-1 Se, see Se• see figure 5 Figure 5 W 0 0 r 00 0 0� 0OO OO O O 000 O o 0 0 0 0000, o o O 0 0 000 E000 O O 000 Example Perforation Patterns Note: The goal in designing the outlet is to minimize the number of columns of perforations that will drain the WQCV in the desired time. Do not, however, increase the diameter of circular perforations or the height of the rectangular perforations beyond 2 inches. Use the allowed perforation shapes and configurations shown above along with Figure 5 to determine the pattern that provides an area per row closest to that required without exceeding it. Urban Drainage and Figure Flood Control District Orifice Details for Drainage Criteria Manual (V.3) Draining WQCV Fie; D.W,A, Orifice Plate Perforation Sizing Circular Perforation Sizing Chart may be applied to orifice plate or vertical pipe outlet. Hole Oia (in) • Hole Oio (in) Min. Sc (in) Area per Row (sq in) n-1 n-2 n-3 1 4 0.250 1 0.05 0.10 0.15 5 16 0.313 2 0.08 0.15 0.23 J 8 0.375 2 0.11 0.22 0.33 7/15 0.438 2 0.15 0.30 0.45 1 2 0.500 2 0.20 0.39 0.59 9/I6 0.563 3 0.25 0.50 0.75 5/8 0.625 3 0.31 0.61 0.92 11/I6 a6d8 3 0.37 0.74 1.11 3 i 1 0.750 3 0.44 0.88 1.33 13 I6 0.813 3 0.52 1.04 1.56 7 8 0.875 3 0.60 1.20 Lao 15 16 0.938 3 0.69 1.38 2.07 1 1.000 1 4 0.79 1.57. 2.36 1 1 I6 1.063 4 0.89 1.77 2.66 1 1 d 1J25 4 0.99 1.99 2.98 1 3 I6 1.18d 4 1.11 2.22 3.32 1 1 4 1.250 4 1.23 2.45 3.68 1 5 16 1.313 4 1.35 2.71 4.06 1 3 8 1.375 4 1.48 2.97 4.45 1 7 16 1.438 4 1.62 3.75 4.87 1 1 2 1.500 4 1.77 3.53 5.30 1 9 16 1.563 4 1.92 3.83 5.75 1 5 d 1 1.625 4 2.07 4.15 6.22 1 11 16 1 1.688 4 2.24 4.47 6.71 1.750 4 2.41 4.81 7.22 1.813 4 2.58 5.16 7.74 R78 1.875 4 2.76 5.52 8.28 1.93d42.000 4 J.14 6.28 9.42 n - Number of columns of perforations Minimum steel plate thickness 1/4 ' 5/16 • Dasigner may interpolate to the nearest 32nd inch to better match the required area, if desired. Rectangular Perforation Sizing Only one column of rectangular perforations allowed. Rectangular Height = 2 inches Rectangular Yridth (inches) = Required Area per Row (sq in) 2" Urban Drainage and Flood Control District Rectongulor Hole Width Min. Steel Thickness 5" 1 4 6" 1 4 7" 5732 " 8" 5/16 9" 11 32 " 10" 3/8 ' >10" 1/2 Figure 5 Y/QCV Outlet Orifice Drainage Criteria Manual (V.3) Perforation Sizing rn.: 0.ms..a.y Final Drainage and Erosion Control Report for First Free Will Baptist Church Project No. 1785-01-00 Appendix III Erosion Control Erosion Control Deposit Letter from Shear Engineering Corporation Rainfall Performance Standard Evaluation Effective Calculations; Sub -basin A Effective Calculations; Sub -basin B Construction Sequence Project No: 1785-01-00 February 6,2003 Re: Erosion Control Cost Estimate First Free Will Baptist; Fort Collins, Colorado According to current City of Fort Collins policy, the erosion control security deposit is figured based on the larger amount of 1.5 times the estimated cost of installing the approved erosion control measures or 1.5 times the cost to re -vegetate the anticipated area to be disturbed by construction activity. a. Based on current unit price data provided by a local erosion control company, the cost to install the proposed erosion control measures is approximately S1878.00. As per City requirements, 1.5 times the cost to install the erosion control measures is $2817.00. b. Based on current unit price data obtained from the City of Fort Collins - Stormwater, and based on an actual anticipated net affected area which will be disturbed by construction activity (approximately 5.00 acres), we estimate that the cost to re - vegetate the disturbed area will be $3275.00 (5655.00 per acre x 5.00 acres). As per City requirements, 1.5 times the cost to revegetate the disturbed area is $4912.50. CONCLUSION: The erosion control security deposit amount required for Old Town North shall be $4912.50. If you have any questions, please contact me at 226-5334. Sincerely, Seth W. Tourney, E.I. Shear Engineering Corporation Page 2 1) ...,. 1785-01-00 Shear Eng: .ing Corporation 5/2003 Designer: SWT First Free Will Baptist Church _ 4:20 PM RAINFALL PERFORMANCE STANDARD EVALUATION PROJECT: First Free Will Baptist Church STANDARD FORM A Developed Ero l i ity Asb Lsb Lb Sb PS Sub -basin Zone (ac) A N (feet) N N A Moderate 5.51 833 0.80 4590 4.41 B Mo erate 0.67 558 0.67 374 0.45 Totals 6.18 803 0.79 LINEAR INTERPOLATION If slope exceeds 5.0 must insert performance standards manually 2 SLOPE 3 LENGTH 0.50 0.79 1.00 800 72.7 75.79 78.1 803.19 75.79 900 72.7 75.84 78.2 CONCLUDE: PERFORMANCE STANDARD = C777Mo Overall Effectivness of Erosion Control Plan must exceed this amount Performance Standard Calcs Performance Page 1 of 1 "n. 1785-01-00 Shear Rnginep-ing Corporation 9/5/2003 D er: SWT First Free Baptist Church .21 PM STANDARD FORM B CONTROL( METHOD VALUE VALUE Roughened Ground 1.00 0.90 Silt Fence 1.00 0.50 Havbnles 1.00 0.80 Asphalt concrete 0.01 1.00 Temporary Vegetation 0.45 1.00 Gravel Inlet Filters 1.00 0.80 MAJOR y SUB AREA A BASIN % BASIN acre AREA C P ALL 75. 9 /o A 5.3 1 Rough 1.50 acres 1.00 havbales 0.50 'acres 1.00 0.80 Silt Fen 2.51 acres 1.00 0.50 EQUATIONS Asphalt 1.00 acres 0.01 1.00 C = WEIGHTED AVG OF C X AREA Check 5.51 P= (WEIGHTED AVG OF P X AREA) X P C= 0.8203 EFF = (1 - P X C) X 100 P = 0.2907 Area * Effectiveness = 4.20 EFF 76.15% Total Area " Eflectiveness = 4.2 Total Area 5.51 acres Overall Effectiveness 76.15% > 75.79% Conclude: Erosion Control Plan is effective Performance Standard Calcs Bffect4veness Page 1 of 2 1785-01-00 L sr: SWT Shear Engine—ing Corporation First Fret Baptist Church ^/5/2003 :21 PM ANDARD FORM B R S A METHOD VALUE VALUE Roughened Ground 1.00 0.90 Silt Fence 1.00 0.50 Haybales 1.00 0.80 Asphalt concrete 0.01 I.00 Temporary Vegetation 0.45 1.00 Gravel Inlet Filters 1.00 0.80 A A BASIN % BASIN acre AREA C P ALL 5.79 0 B 0. oug i 0.25 acres havbales acres 1.00 0.80 Silt Fen acres 1.00 0.50 EQUATIONS Asphalt 0.42 acres 0.01 1.00 C = WEIGHTED AVG OF C X AREA Check 0.67 P= (WEIGHTED AVG OF P X AREA) X P C= 0.3794 EFF=(1-PXC)X100 P= 0.3851 Area * Effectiveness = 0.57 EFF 85.39% ota rca ectiveness 0.57 Total Area 0.67 acres Overall Effectiveness S539% > 75.79% Conclude: Erosion Control Plan is effective Performance Standard Calcs Effectiveness Page 2 of 2 CONSTRUCTION SEQUENCE PROJECT: First Free Will Baptist Church STANDARD FORM C SEQUENCE FOR 2003-2003 ONLY COMPLETED BY:SWT/Shear Engineering Corp. Indicate by use of a bar line or symbols when erosion control measures will be installed. Major modifications to an approved schedule may require submitting a new schedule for approval by the City Engineer. Year 03 Ivtonth M A M J J A S O N D DVERLOT GRADING **+ r+* WIND EROSION CONTROL Soil Roughening *+* Perimeter Barrier Additional Barriers Vegetative Methods Soil Sealant Other RAINFALL EROSION CONTROL STRUCTURAL: SedimentTrapBasin *** Inlet Filters Straw Barriers Silt Fence Barriers *** Sand Bags Bare Soil Preparation Contour Furrows Terracing Asphalt/Concrete Paving Other VEGETATIVE: Permanent Seed Planting Mulching/Scalant Temporary Seed Planting Sod Installation N e t t i n gs/M a ts/B I anke i s Other rtt+ +++ rrt+ rrt* +++ rt++ ### ### ### ### ### ### ### ### ### STRUCTURES: INSTALLED BY: First Free Will Baptist Church MAINTAINED BY: First Free Will Baptist Church VEGETATION/MULCHING CONTRACTOR: First Free Will Baptist Church DATE PREPARED: 02/06/03 DATE SUBMITTED: 02/07/03 APPROVED BY THE CITY OF FORT COLLINS ON: Final Drainage and Erosion Control Report for First Free Will Baptist Church Project No. 1785-01-00 Appendix IV Stuffer Envelope Historic Drainage Plan Drainage and Erosion Control Plan \< LEGEND �� ) \ `♦ / ' I I \ ) \\ ,�/� ' ------ .ten_..----- EXISTING Y CONTOUR ------1 ♦. /' % / II \ \Y/ % r-------- A\(' ,)//% /// r ,r / ,/ .' ,---"'o---- EXISTING s' CONTOUR ,/JI I lIl I I / ' / /E M M M ■ 6151N BOUNDARY 10 /� \\ \\ L----- /--MTICAI J ♦�/ r I 1 I r i ' '/ ,'' / ,"�, B = AREA INIXACRES A\ i I I CI I i / / / COEFFICIENTS (tDO YR. MNI) - �moon 11 1 \ 1 I 1 `i 1 'I i I J i i O = DESIGN POINT DESIGNATION '_—mot RUNOFF DIRECTION I I ' v AV A I I I I ; A V A A A AV A A V A A AAAAOAAA\ 1 AV , I I I 1 ♦ \i,pp\`\\ \\ \ 1 1 7. I 1 I I i ♦ 1 , //l 11 lv i vI v vv vv vv A vv vI vvq"NV F >r*e ♦ V ♦` i i ,','i/ �V A \. A AV AV A A\ \\ \VA `�VA �VAAVAA\ \V AV AV A 11 ,�111 PIP \ I E.M. c...ee I IItiI 11 I n.h,..3Rtw92 / I I / \ \ I / , , / ' 1 ♦ \ \\\\\\\ \ \ \ \ GRAPHIC SCALE I J i i I I I I rim �� 1 ; ,,„ I \\\\\\\\\+\ \ \ ' 111111 �11 //r��`\ ���\ 1 1 i/,'i i' 1 I I 1 i _\\\\\\\\\\ \ \ \\ \ \ \\ IIIII�C'' n _l I 11 II , �' �/� / I I 'I I' \\\U\\\\\ \ \\ \ \\ \\ \ E i i' Illllr: _I � f- 1 / / / I / I ♦ I 1 II i F\ \\\ \ \ \ \ \ ei5r w1I i F I I I I / /, , / 1 I 1 III 4q\ \0\ \ \ \ \ \ \ 6pl// , / I I" — �'�' i • '' / / / '/ /i / / r I III \ �\\\\\\\ \\ \ \ \ \ III \ \\p\\\\\\ \lit \ \ 1 it I\\\\\ / I I I 1 1 / 1 \`♦ \ IIIII I I \ \ kill, i1I;,;ill/,;1i� II 0I IIII� 1 I II \V I I I I I I \ \ `\ N I 1 _\ ` _ — -- �c-- s— +r�.eri_ :�. /S �—t — — r I I I ♦ L,7 _ g_ Mir L i West T#Iby Road; «, ,, ,b1,' -- _ ___ / u 1j __5-1________ -� �— _—y __—� _- RIDGEWOOD HILLS P.U.D. UNPLATTED AENSIONS uou. pale FEBRUARY 2003 pa�m B.R.B. LUID o..w.� P.x Boo1i a`cke B.w.s. FIRST FREE WILL BAPTIST CHURCH pai11'n 5cak to i 311, Ala'.__ P W s. SHEAR ENGINEERING CORPORATION ""` HISTORIC DRAINAGE PLAN 036 SO. COLLEGE AYE, SURE 12. FORT (AWNS, COLOMM W525 FIRST FREE WILL BAPTIST CHURCH PHONE: (970) 226—M34 (970) 226-461 PAC: (970) 282-0311 FORT COLLINS. COLORADO E1 1 v v v \ �� LEGEND / - — . --- EXISTING 5' CONTOUR n,(/ 'T —"'o--- — EXISTING 5' CONTOUR�.�� —\' ✓ _ t.DS 0.5a I / \ / I / / / / /—*9n— PROPOSED 1' CONTOUR —ASTO— PROPOSED 5' CONTOUR — \tWIN BOUNDARY BOUNDARYSKVEHSOU1 F�TF-- --__ MINOR IN BOUNDARYSWOON T. DESIGNATION ( ( \ \ I ( I II I A = WIN °=OEPoCERU( 0B AREA INACRES COEFFICIENTS YR. EVEN o = OeslcN vowr DtslcrunoN I \ \ \ \ \ \ \\0.17 0.25 ` I PROPOSED STORM SEWER \\ \,.. \ \\ 1 1 \ \ I mrxs FINISHED FLOOR ELEVATION ew 06mxx g \q g g y M ' R r pP \ & '8\ 'b. \ 1 \ \\ \\\\(\ 1 I S SILT FENCE \ \ 1 \A4\\` \\ 1 �8 STRAW BALE DIKES --------� A A RUNOFF DIRECTION J w \ I'I Na o� • I / ,� \\ 4.46 C.54 \ m a 6Re 1\ \ \\ \ \ \ 1 I j v� \\ _ v LMan 0T 0I Fan ' FI O� 1 1 , �? I � �• ` � �� ,1 / I � Ir VAVAOAV\V A V A V A v -r. \\\\\\ \\\\ \\ \\ \\ \\ GRAPHIC SCALE e Dm r I III \ \ \ \ \ \ GRAPHIC SCALR / • � T I ' ®� ' '/ / �// / /// // /_ /// I / x a , .p x' TI.E a K=Dxs I I j A �\\A\A\V\VAA\ \\\V\AA ' 0'eatTdn MIN 50543it \Rv\ r 4*�A loe t /4RAo•A etentiorPondFX "/ A \ \ >4 n �rWVR.s 9 I Diru°Ei/\ \� sw \ \\\\ \ sr.lx \\\ 40.93!58 NLR e/\\\NIPI1I\\,VWKU mA / PAD STORM BI A'KA'N1LT M \ STM rr w(mc�E 1 Ws avI.ea I I i i� \ �� / / / j / •• i ttE wDPDd w ter. 11 s�`ir. D13 Erul DN r r if(�I i .1 Z Nrar. T I � ESM . \ • S1. \LM EX vl� t �E7���1♦Efl♦®tit ����SaE3�E-ram ��<�tT'<LSFJ•Sil ac;�©gym oo®�� =min \ j I City of Fort CoRim, womb E%,5• Dra lro eEMAW)/ Z �T/ GTIM PEAR APPROVAL i d. IY rts (m eEUA1�1 J I^ West/Trilby R9gd DAM RIDGEWOOD IHHIR •1T 1 \ \ \ \ I \ GEC 6raaaaaaa ONE \ \ \ \ OEwzn n buff O M� b OdIM{r�k -_S •M Oi���rcr��6 tl,i4 tlY�tlY Ylltlrk M�p��wk11,11110 ��� � �n • k�tif k n �le Maaaw JdktlW �y Ir_ ,1•N kk IY miMY � �. Ny,n o.u.a D�NI SHEAR ENGINEERING CORPORATION r'"F DRAINAGE AND EROSION CONTROL PLAN (kip— s. omNk Paid �" C^E,rc, R.W.S. FIRST FREE WILL BAPTIST CHURCH A636 SO. COLLEGE AVE, SURE 12, FORT DOWNS, COLORADO 80525 FIRST FREE WILL BAPTIST CHURCH P.D.P. DsKu• Spk T•s J0 AD'-orc B.W.S. PRONE: (970 226-5331 YN N e ) (aTo) zz6-usl FA%: (970) zaz-oSEI FORT COLLINS, COLORADO