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HomeMy WebLinkAboutDrainage Reports - 10/27/1997Ke=a!ed Rep® HEAR ENGINEERING / CORPORATION 0 FINAL DRAINAGE AND EROSION CONTROL REPORT for WESTFIELD PARK P.U.D. (Previously Stockbridge P.U.D.) Ft. Collins, Colorado Prepared for: PROGRESSIVE LIVING STRUCTURES, INC. 4190 North Garfield Avenue Loveland, Colorado 80538 Prepared By: l SHEAR ENGINEERING CORPORATION Project No: 1005-44-94 Date: October, 1997 4836 S. College, Suite 12 Ft. Collins, CO 80525 (970) 226.5334 FAX (970) 282-0311 August 26, 1996 Project No: 1005-44-94 Basil Hamdan City of Ft. Collins Storm Water Utility P.O.. Box 580 Ft. Collins, Colorado 80524 Re: Stockbridge P.U.D.; Ft. Collins, Colorado Dear Basil, Enclosed please find the Final Drainage and Erosion Report and Plans for Stockbridge P.U.D. The hydrology data and the hydraulic analysis presented in this report complies with the requirements of the City of Fort Collins Storm Drainage Criteria Manual; dated March, 1984, and the Erosion Control Reference Manual. The analyses and design also complies with the recommendations of the Foothills Basin (Basin G) Master Drainage Plan. No modifications to the Foothills Master Drainage Plan have been considered. If you have any questions or comments, please call me at 226-5334. Sincerel , Brian W. Shear Shear Engineering Corporation BWS/mb cc: Don Frederick; Frederick Land Surveying Leo Schuster; Progressive Living Structures, Inc. 4836 S. College, Suite 12 Ft. Collins, CO 80525 (970) 226-5334 FAX (970) 282-0311 MAD a i Page 1 Final Drainage and Erosion Control Report Westfield Park P.U.D. L GENERAL LOCATION AND DESCRIPTION A. Property Location 1. Westfield Park P.U.D. (formerly known as Stockbridge P.U.D.) is located in the Northeast Quarter of Section 34, Township 7 North, Range 69 West of the 6th P.M., City of Fort Collins, Latimer County, Colorado. 2. More specifically, it is located on the south side of West Horsetooth Road, approximately 1/2 mile west of the intersection of West Horsetooth Road and South Shields Street. 3. The site is bounded on the west by the Second Imperial Estates Subdivision, on the north by West Horsetooth Road, on the east by unplatted land, and on the south by the proposed Mountain Ridge Farm P.U.D. subdivision. 4. The Pleasant Valley and Lake Canal parallels the eastern property line of the site. The ditch is not located on the Westfield Park P.U.D. property. a. . The existing irrigation ditch crosses the unplatted property to the east of Westfield Park P.U.D. from north to south approximately 1,400 feet west of South Shields Street. The irrigation ditch then extends. from north to south through the proposed Mountain Ridge Farm P.U:D.'and beyond to its confluence with Fossil Creek. b. The ditch is discussed in detail in the Foothills Basin Master Drainage Plan. It is assumed that the ditch is overtopped during storm events equal to or larger than the 100-year event. c. Ditch company approvals will be required. B. Description of the Property 1. Westfield Park P.U.D. is a proposed residential subdivision in the City of Fort Collins, Colorado. The subdivision will consist of single family homes on individual lots. There are a total of 118 lots proposed. 2. Westfield Park P.U.D. has a platted area of approximately 31.02 acres. 3. The site is currently vacant and is covered with native vegetation. Public water lines exist within the right-of-way of Seneca Street. a. The water lines in the Seneca Street right-of-way were "potholed" on Wednesday, July 17, 1996 in order to verify their horizontal and vertical locations. b. Existing water line locations will in some cases, dictate the vertical location of storm water conveyance crossings of Seneca Drive. Page 2 Final Drainage and Erosion Control Report Westfield Park P.U.D. H DRAINAGE BASINS AND SUB -BASINS A. Major Basin Description 1. The majority of Westfield Park P.U.D. is a part of Basin "G" of the Foothills Drainage Basin as identified in the 1981 Basin Master plan by Resource Consultants, Inc. This area is designated as Basin "A" on the Final Drainage and Erosion Control Plan for Westfield Park P.U.D. a. The Basin fee rate for the Foothills Basin is $5,024 per gross acre according to the development fee section of the City of Fort Collins Development Manual. This may be reduced if detention is provided. 2. The Foothills report identified the need to construct Regional Detention facilities within the Westfield Park P.U.D. area. The description of those improvements were generally defined in the Foothills report as follows: a. Build storm water detention facilities on the west side of the Pleasant Valley and Lake Canal that will provide 14 acre feet of detention volume and reduce the peak discharge from the 100-year "Major" storm from 170 to 23 cubic feet per second (cfs). b. Construct a 24 inch diameter storm sewer from the detention facility downstream under the irrigation ditch and ultimately, through undeveloped land to the east and an existing low density (1 lot per 5 acres) residential neighborhood (Skyline Acres) to the intersection of West Horsetooth Road and South Shields Street. c. The Foothills report has been recently updated by Faucett Engineering Services and is entitled Foothills Master Drainage Plan Update and Westfield Park P.U.D. Regional Detention Pond Analysis. i. The Foothills Master Drainage Plan Update and Westfield Park Regional Detention Pond Analysis was required as a condition by the Stormwater Utility due to apparent insufficiencies in the original Foothills Master Drainage Plan. ii. Refer to the Foothills Master Drainage Plan Update and Westfield Park P.U.D. Regional Detention Pond Analysis for additional information. 3. The site is located in reach 4 as designated by the Drainage Master Plan. Reach 4 is the upper reach of the Foothills Basin. a. At the time the original Foothills report was written there was no detention provided within the limits of reach 4. The Master Drainage plan indicates that serious drainage problems exist in the reach because of the lack of detention in reach 4. 4. Regional drainage improvements will be subject to reimbursement according to the City of Fort Collins Stormwater Utility "Developer Repayment Program". Page 3 Final Drainage and Erosion Control Report Westfield Park P.U.D. II DRAINAGE BASINS AND SUB -BASINS A. Major Basin Description 5. The proposed 15" storm sewer outfall from the proposed regional detention pond will . cross private property. Easements will be required on unplatted property to the east. 6. The outfall will also cross a waterline that is in Richmond Drive. This waterline services the homes in Skyline Acres. a. 'According to the South Fort Collins Water District the water line in Richmond Drive is a 4" ACP and it is located 10' east of the west R.O.W. line of Richmond Drive. 7. A small portion of the site is situated in the McClellands and Mail Creek Basin. These sub -basins are designated B 1 and B2 on the Final Drainage and Erosion Control Plan for Westfield Park PUD. These sub -basins will not contribute to the regional detention basin constructed with this project but to Regional Detention Pond 247. a. It is our understanding that RBD considered this portion of Westfield Park P.U.D. in the drainage design of Regional Detention Pond 247. b. Detention Pond 247 was constructed as part of the Mountain Ridge Farm P.U.D. c. Refer to page A6 in Appendix A - SWMM Input File and Updates and Model Schematic in the Final Design of Regional Detention Pond 247 and Outfall for the McClellands and Mail Creek Basin. Page A6 states that 3.2 acres from Stockbridge (Westfield Park P.U.D.) contributes to Detention Pond 247. A copy of page A-6 is included in Appendix IV of this report for reference. d. Sub -basins B1 and B2 have an actual combined area of 2.97 acres. This is less than the 3.2 acres approximated with the Final Design of Regional Detention Pond 247 and Outfall for the McClellands and Mail Creek Basin. e. A swale has been provided along the south property line of lots 88-96 ( south half of sub -basin B-1) to convey the rear lot flows to Seneca Street. A swale has been provided along the south property line of Lots 97-102 (sub - basin B-2) to convey the rear lot flows to the Westfield Park Pond. The swale is located in a 20' drainage easement located on the Mountain Ridge property. This is considered an interim condition. Ultimately, the channel will be need to be modified with Mountain Ridge Farm final design. This sub -basin will eventually contribute to the Detention Pond 247 in accordance with the City Master plan for the McClellands and Mail Creek Basin. Page 4 Final Drainage and Erosion Control Report Westfield Park P.U.D. H DRAINAGE BASINS AND SUB -BASINS B. Sub -Basin Description 1. Off -site storm drainage currently enters the site via overland flows from Imperial Estates. Drainage basins and flows are identified on the Foothills Master Drainage Basin Report. Imperial Estates is the primary contributor of off -site runoff. a. There is no detention provided with Imperial Estates and the Second Imperial Estates Subdivisions. b. Detention provided with the development of Westfield Park P.U.D. will also detain the off -site runoff from Imperial Estates and the Second Imperial Estates Subdivisions. 2. City of Fort Collins aerial photos were utilized to delineate the off -site sub -basins as they contribute storm drainage to Westfield Park P.U.D. and West Horsetooth Road. An exhibit delineating these offsite sub -basins is included in Appendix V. 3. There are three (3) primary offsite sub -basins located in Imperial Estates and the Second Imperial Estates Subdivision. They are designated OS-1 through OS-3. a. Sub -basin OS-1 contributes runoff directly to Westfield Park P.U.D. This runoff will be conveyed to the regional drainage facility. b. Sub -basin OS-2 contributes runoff directly to West Horsetooth Road. This stormwater is conveyed east in the road side swale along the south side of West Horsetooth Road. This runoff will be conveyed to Westfield Park P.U.D. and the regional drainage facility. c. Sub -basin OS-3 contributes runoff to an existing culvert located at a low point on West Horsetooth Road between Linda Lane and Goodell Lane. The stormwater is then conveyed north into Rossborough Filing III via a storm sewer that was constructed with Rossborough Filing III. 4. Offsite sub -basin OS-1 is further divided into several other minor basins (See Offsite Drainage Exhibit - Imperial Estates in Appendix V). These minor basins contribute runoff to Westfield Park P.U.D. at various locations and are relatively small. The primary outfall from Imperial Estates is at the eastern terminus of Imperial Drive. a. The proposed grading along the common property line will NOT divertthe flow from all of the rear lots along Crescent Drive to the proposed inlet at the terminus of Imperial Drive. The grading along the property line on the north side of Imperial Drive to divert water to the proposed area inlet will end about 80 feet north of Imperial Drive. Page 5 Final Drainage and Erosion Control Report Westfield Park P.U.D. II DRAINAGE BASINS AND SUB -BASINS B. Sub Basin Description (continued) 4. continued b. The rear lots which do not contribute stormwater to the proposed inlet will instead contribute runoff to the rear lots of Lots 28-30, 49-51 and 68 of Westfield Park P.U.D. The grading of these lots will be provided with side lot swales and easements to convey the offsite runoff around the proposed houses. 5. The design of the ofsite stormwater infrastructure considers the contribution from these offsite basins. a. Peak flows generated with the updated SWMM model were used in the design of the Painted Desert Court storm sewer and the channel along West Horsetooth Road (Profile A). Street capacities were also checked with respect to the SWMM generated flows. b. These flows tend to be 3-4 times larger than the peak flows generated using the Rational Method. c. The remaining internal stormwater infrastructure was designed with peak flows generated using the Rational Method because there are minor contributions from the offsite areas. 6. Generally, the Westfield Park P.U.D. site slopes from west to east at one to two percent. The development of the site will create ten (10) sub -basins within Basin "A" which contribute stormwater runoff to the regional detention pond via various paths. The table below summarizes the characteristics of the ofsite sub -basins. Design Design Sub -basin Area C2 Point Item Al 7.00 0.25 1 Pond A2 1.34 0.60 2 Inlet/Pipe/Swale A3 0.92 0.56 3 Inlet/Pipe/Swale A4 0.43 0.83 4 Inlet/Pipe/Street A5 9.03 0.51 5 Inlet/Pipe/Street A6 0.33 0.85 6 Inlet/Pipe/Street A7 2.51 0.62 7 Inlet/Pipe/Street Ala 2.75 0.38 7a Culvert A9 1.35 0.58 9 Inlet/Pipe/Street A10 3.65 0.50 10 Inlet/Pipe/Street All 0.14 0.83 11 Inlet/Pipe/Street The sub -basin areas m' the table above do not include the offsite contributing areas from Imperial Estates. Offsite flows are conveyed to the pond through sub -basins Al, A31 A5, A7, A9 and A10. These flows are considered in the design of the storm sewer infrastructure and the determination of street capacity. Page 6 Final Drainage and Erosion Control Report Westfield Park P.U.D. III DRAINAGE DESIGN CRITERIA A. Regulations 1. This final report and the final Grading, Drainage and Erosion Control Plans for Westfield Park P.U.D. were prepared in accordance with the requirements of the current City of Fort Collins Storm Drainage Design Criteria and Erosion Control Criteria. 2. Recommendations of the Foothills Basin (Basin G) Drainage Master plan were also considered in the design of the stormwater management infrastructure for Westfield Park P.U.D. The final detention design is based on the Foothills Master Drainage Plan Update and Westfield Regional Detention Pond Analysis. 3. Requests for Regional drainage improvement reimbursement will be in accordance with the City of Fort Collins Stormwater Utility "Developer Repayment Program". B. Development Criteria Reference and Constraints 1. West Horsetooth Road is not currently constructed to full arterial standards adjacent:... to the north boundary of the project. Improvements to. the southern. half of West Horsetooth Road will be completed as part of phase 1 of this.project. a. West Horsetooth Road will be widened to full arterial width (70' flowline to flowline) along the frontage of Westfield Park P.U.D. as part of this project. b. Curb gutter and detached walk will also be constructed along the south side of West Horsetooth Road to the western property line of Westfield Park P.U.D. c. The existing box culvert under Horsetooth Road at the Pleasant Valley and Lake Canal will be extended to the south. 2. Imperial Estates Second Subdivision is fully developed along the western property line of Westfield Park P.U.D. Grading along the western property line will match the existing elevations at the property line. a. Grading along the western property line will also need to be done to allow for the offsite runoff to flow onto the site as it does under existing conditions. b. Imperial Estates is the primary reason for the regional detention requirements. c. An emergency overflow structure is required by the City of Fort Collins Stormwater Utility. 3. Mountain Ridge Farm P.U.D. is located to the south of Westfield Park P.U.D. Earthwork and utility installation are in progress for the initial phase of Mountain Ridge Farm P.U.D. at the time of this submittal. All grading along the southern property line of Westfield Park P.U.D. will have to match the proposed future final grades for Mountain Ridge Farm P.U.D. Page 7 Final Drainage and Erosion Control Report Westfield Park P.U.D. III DRAINAGE DESIGN CRITERIA B. Development Criteria Reference and Constraints 4. Stormwater flows cross the site from west to east. A certain amount of storm drainage infrastructure is required to intercept these flows and divert them into the detention pond. The design of this infrastructure will consider offsite flows.. a. The storm sewer infrastructure is designed toconvey the peak flows generated by the 2-year storm event at a minimum. b. This capacity has been increased as needed depending on the downstream street capacities. c. Overflow swales will be provided at the low points to carry excess flows to the pond. 5. All grading along the eastern property line will have to match the existing grading of the Pleasant Valley and Lake Canal. C. Hydrologic Criteria 1. Runoff calculations used in the design of the interior storm sewer infrastructure are based on the "Rational' method. The 2, 10, and 100-year storms have been analyzed. a. Peak flows generated using the Rational Method are used for the design of the storm sewer infrastructure at Design Points 2 and 5 and for all rear lot swales since the offsite contributing areas to these points are minor. b. The storm sewer inlets along Seneca are sized to intercept the flows generated by the 2-year storm. In some cases the inlet capacity actually exceeds the peak flows generated by the 10-year storm. Allowable flow depths are never exceeded for the 100-year storm because the stormwater will overflow into the pond when the depth at the flowline exceeds 0.70 feet. The allowable depth at the flowline on Seneca Street (Collector Street) for the 100-year storm is 1.13 feet or 6" over the the crown. 2. Detention pond sizing is based on the recommendations of the Foothills Master Drainage Plan Update and Westfield Park P.U.D. Regional Detention Pond Analysis. 3. The release rate from the pond is based on recommendations of the Foothills Master Drainage Plan Update and Westfield Park P.U.D. Regional Detention Pond Analysis. 4. We have modeled the outlet structure release rate taking into account the fact that the water quality control device will essentially allow zero (0) cfs release rate up to the elevation of 96.0 feet. Page 8 Final Drainage and Erosion Control Report Westfield Park P.U.D. III DRAINAGE DESIGN CRITERIA C. Hydrologic Criteria 4. The two primary conveyance elements of the offsite stormwater through the site have been designed based on the peak flows generated by the SWM model that is included. in the Foothills Master Drainage Plan Update and Westfield Park P.U.D. Regional Detention Pond Analysis. a. Painted Desert Court and the storm sewer that will be constructed with it are the primary means of conveying stormwater from the majority of sub -basin OS 1 to the pond. b. The channel along the south side of West Horsetooth Road and the 3 'x 8' box culvert under Seneca Street at West Horsetooth Road are the primary means of conveying stormwater from the majority of sub -basin OS2 to the pond. D. Hydraulic Criteria 1. Storm sewer inlet design is based on the inlet curves provided in the City of Fort Collins Drainage Criteria Manual. 2. Storm sewer design is based on Mannings Equation with Mannings coefficients as suggested in the City of Fort Collins Drainage Criteria Manual. IV DRAINAGE FACILITY DESIGN A. General Concept 1. Detention will be provided in a single pond on the east side of Seneca Street. The detention pond is located in Tract B as designated on the Final Plat. Tract B will be dedicated as Utility, Drainage, Access and Maintenance Easement on the Final Plat. a. The maximum allowable release rate from the primary pond according to the Foothills Master Drainage Plan Update and Westfield Park P.U.D. Regional Detention Pond Analysis is 2.5 cfs. b. A total of 16.40 acre feet of detention volume is required according to the Foothills Master Drainage Plan Update and Westfield Regional Detention Pond Analysis which used a release rate of 2.50 cfs. c. The volume requirement for zero (0.0) release is also 16.4 acre feet. 2. Off -site stormwater from Imperial Estates will be conveyed to the on -site detention pond via a combination of: a. Overland flow b. Gutter flow c Storm sewer flow d. Channel flow Page 9 Final Drainage and Erosion Control Report Westfield Park P.U.D. IV DRAINAGE FACILITY DESIGN A. General Concept 3. The detention pond is designed to maximize the amount of storage volume. a. Maximum allowable side slopes in the pond will be 4:1. (run:rise). b. The pond bottom will have a minimum cross slope of 0.02 ft/ft (2.0%). 4. Valley pans will be provided in all rear lot swales having slopes less than 0.02 ft/ft (2.0%). B. Specific Details -Detention Pond 1. The detention pond is located in Tract B. A summary of the pond elements is listed below: Bottom of Pond elevation (outlet structure) Top of Berm elevation Detention Volume Provided at elev. 5102.20 Detention Volume Provided at elev. 5101.20 Detention Volume Required Required 100 year W. S. Elev. Freeboard Provided Total Contributing Area to Pond 100 year release rate Outlet Pipe Slope of outlet pipe Capacity of outlet pipe (HW/D = 1.0) = 5094.00 feet 5102.20 feet 20.75 ac-ft = 903,802 cubic feet 16.25 ac-ft = 708,005 cubic feet = 16.40 ac-ft 714,384 cubic feet = 5101.23 feet 0.97 feet. = 97.4 acres = 2.50 cfs = 15 inch RCP 0.005 ft/ft 4.95 cfs a. The total volume is based on the Foothills Master Drainage Plan Update and Westfield Park P.U.D. Regional Detention Pond Analysis. b. The release rate is also based on the Foothills Master Drainage Plan Update and Westfield P.U.D. Regional Detention Pond Analysis. Page 10 Final Drainage and Erosion Control Report Westfield Park P.U.D. IV DRAINAGE FACILITY DESIGN B. Specific Details -Detention Pond 2. The table belows summarizes the stage - storage - discharge relationship for the pond. This model Refer to pages 1-2 in the detention section of Appendix I. Elevation Stage Storage Storage Release ft. ft. cf. ac-ft cfs 5044 0 0 0 0 5095 1 7,202 0.17 0.00 5096 2 41,696 0.96 1.25 5097 3 107,337 2:46 1.57 5098 4 203,206 4.66 1.83 5099 5 329,532 7.57 2..06 5100 6 488,817 11.22 2.27 5101 7 669,179 15.36 2.45 5101.7 7.7 804,989 18.48 2.58 5102 8 863,309 19.82 11.17 5102.2 8.2 903,802 20.75 21.05 Notes: Orifice Invert Water Quality Elevation Overflow Weir invert Top of Berm 3. According to the SWM model, the required pond volume with no release is 714,384 cubic feet (16.40 ac-ft). This is 148,925 cubic feet less than the total volume provided. 4. A Y x 5' box with a 15" RCP outlet pipe will be installed at the outfall from the pond. An orifice plate will be bolted over the outlet pipe with a 0.48 foot (5 7/8") inch diameter orifice. The restriction plate will control the release. A summary of the outlet structure is listed below. Diameter of orifice = 0.48 feet Invert Elevation = 94.00 feet Top of box = 96.0 feet Mannings n = 0.013 Slope of Outlet Pipe = 0.005 ft/ft Outlet Pipe Capacity = 4.57 cfs 5. A twenty (20') foot wide emergency overflow weir will be constructed at the top of the berm to convey any flows which exceed the capacity of the pond to the east. The invert of the overflow weir is 101.7 feet. The discharges listed above take into account weir flow above 101.7 feet. Page 11 Final Drainage and Erosion Control Report Westfield Park P.U.D. IV DRAINAGE FACILITY DESIGN B. Specific Details -Storm sewer Profile "A" - Box Culvert under Seneca Street at Horsetooth Road 1. The box culvert will convey stormwater from sub -basins A6, A7, and OS2 to the pond. The design flow to the box culvert (DP 7a) is summarized in the table below. This design flow is the Q100 taken from the SWM model. The channel and the box culvert are sized to convey these flows. Design Contributing Area Q100 Point Sub -basins acres cfs Design 7a 7a & OS2 49.1 178.9 channel/culvert 2. The culvert under Seneca Street at West Horsetooth Street is a 3'x8' Reinforced Concrete Box Culvert (RCB). The center of the box is located at Seneca Street centerline station 0+92.00. a. The RCB has a slope of 0.005 ft/ft (0.5%). b. The maximum flow depth at the culvert before the street is overtopped is 4.45 feet. c. The capacity of the box with a HW/D ratio of 1.64 is approximately 216 cfs. 3. Installation of the box culvert will require the lowering of the existing 12" water line in Seneca Street. 4. A five (5') Type "R" inlet will be installed on the both sides of Seneca Street at the low point near Horsetooth Road (Design Points 6 & 7 ). An 18" RCP storm drain will convey the intercepted flows into the south side of the Tx8' box culvert. Mamrings n for RCP is 0.013. The table below summarizes the design of the inlets and the storm sewer Design Design Inlet Pipe Pipe Pipe 100-year. Storm Q Capacity Diam. Slope Capacity Overflow DP year cfs cfs ft. ft/ft cfs cfs 7 10 6.16 6.4 1.5 0.10 20.4 6.02 6 10 0.87 6.4 1.5 0.10 20.4 1.55 Note: The overflow is the flow generated during the 100-year storm which exceeds the inlet capacity at each of the design points. Inlet capacity is based on a flow depth of 0.70' at the flowline. Above 0.7 feet at the flowline the stormwater will overflow into the pond. The crown is 0.63 feet above the flowline on Seneca Street. Allowable flow depth is 6" over the crown or 1.13 feet above the flowline. Page 12 Final Drainage and Erosion Control Report Westfield Park P.U.D. IV DRAINAGE FACILITY DESIGN B. Specific Details -Storm sewer Painted Desert Court Storm Sewer 1. The Painted Desert Court storm sewer will convey stormwater from sub -basins A3, A9, A10 and OS1-part to the pond. The peak 2 and 100 year flows to design points OS1, 9, 10 and 3 are summarized in the table below. The flows to OS 1 are taken from the SWM model. The stormwater will be conveyed to the pond via a combination of swale, street and sewer flows. Design Contributing Area Q2 Q100 Point Sub -basins acres cfs cfs Design OS 1 OS 1-part 17.22 10.6 75 inlet/pipe/overflow swale 10 A10 4.04 2.4 39.8 inlet and pipe/street 9 OS1 & A9 18.57 0.6 33.2 inlet and pipe/street 3 A3 0.92 1.7 6.0 inlet/pipe 3 ALL 23.14 0 15.4 inlet/pipe/overflow swale 2. The table below summarizes the storm sewer design at the various design points. All pipe is RCP and has a Mannings n value of 0.013. Overflow will be conveyed in the street or an overflow swale to the pond. Pipe capacities are based on Mannings Equation Storm sewer Design Design Inlet Inlet 100-year Design Storm Q size Capacity Overflow Point year cfs ft. cfs cfs OS1 2 10.6 area 13.4 61.6 9 10 1.1 5 7.0 26.2 10 2 2.4 5 7.0 32.8 9 &10 10 19.4 NA NA 58.9 3 2 30.6 5 4.5 10.9 Design Design Pipe Pipe Design Storm Q Diam Capacity Point Y.L. cfs ft. cfs Notes OS1 2 11.1 1.5 16.2 9 2 7.0 1.5 20.9 10 2 7.0 1.5 7.4 9 & 10 10 27.1 2408 29.8 3 10 31.6 2408 29.8 Pressure flow 0 Page 13 Final Drainage and Erosion Control Report Westfield Park P.U.D. IV DRAINAGE FACII.ITY DESIGN B. Specific Details -Storm sewer Profile B - culvert under Seneca Street @ sta. 6+36.74 1. Profile "B" will convey stormwater from sub -basins A4, A5 and OS5 under Seneca Street to the pond. Two year peak flows are used as the minimum flows to be intercepted by the inlets. The peak 2,10 and 100 year flows to design points 4 and 5 are summarized in the table below. Design points are located on the east and west sides of the street at Sta. 6+36.74 on Seneca Street between Ambrosia and Corydalis Courts. Design Contributing Area Q2 Q10 Q100 Point Sub -basins acres cfs cfs cfs Design 5 5 & OS5 10.83 10.9 19.1 56.2 inlet and pipe/street 4 4 0.43 1.2 2.0 2.5 inlet 4 4,5 & OS5 11.26 1.2 5.8 40.9 pipe/overflow 2. The table below summarizes the design of inlets of Profile 'B". Design Inlet Design Flow Inlet 100-year Size Flow Depth Capacity Overflow Point ft. cfs ft. cfs cfs 5 15 16.58 1.03 33.75 11.55 4 10 2.01 1.03 21.25 0 3. The table summarizes the design of the storm sewer at design points 4 and 5 From To Flow Pipe Mannings Slope Capacity Notes DP DP in Pipe Diam. "n" cfs ft. ft./ft. cfs 5 4 19.08 1.5 0.013 0.005 22.28 3 pipes 4 pond 52.87 2.0 0.012 0.005 51.99 3 pipes Profile C - Storm sewer @ Low Point on East Purple Sage Court 1. Profile "C" will convey stormwater from sub -basin A2 to the pond. The peak 2,10 and 100 year flows to design point 2 are summarized in the table below. Design Contributing Area Q2 Q10 Q100 Design Point Sub -basins acres cfs cfs cfs 2 A2 1.34 1.91 3.35 6.74 inlet/pipe/overflow Page 14 Final Drainage and Erosion Control Report Westfield Park P.U.D. IV DRAINAGE FACILITY DESIGN B. Specific Details - Storm Sewer Profile C - Storm sewer ® Low Point on East Purple Sage Court (continued) 2. The table below summarizes the inlet sizing for Profile C. Design Inlet Flow Inlet Overflow Point Size Depth Capacity ft. ft. cfs cfs 2 5.0 0.50 4.52 2.22 3. The table below summarizes the storm sewer design for profile C. From To Flow Pipe Mannings Slope Capacity DP DP in Pipe Diam. "n" cfs ft. ft./ft. cfs 2 Pond 4.52 1.25 0.012 0.007 5.85 Profile D - Storm sewer on Horsetooth Road 1. Profile "D" will convey nuisance, flows from sub -basin All to the pond. The peak 2,10 and 100 year flows to design point 2 are summarized in the table below. Design Contributing Area Q2 Q 10 Q 100 Point Sub -basins acres cfs cfs cfs . 11 All 0.14 0.39 0.66 1.30 2. The table below summarizes the inlet sizing for Profile C. Design Inlet Flow Point Size Depth ft. ft. 11 5.0 0.50 Inlet 100-year Capacity Overflow cfs cfs 7.0 0.0 Design inlet/pipe/overflow 3. The table below summarizes the storm sewer design for profile C. From To Flow Pipe Mannings Slope Capacity DP DP in Pipe Diam. "n" cfs ft. ft./ft. cfs 11 Pond 1.30 1.25 0.012 0.005 4.95 Page 15 Final Drainage and Erosion Control Report Westfield Park P.U.D. IV DRAINAGE FACILITY DESIGN C. Specific Details -Swales 1. Swales are provided at- various locations to convey rear lot flows to the streets and to convey flows that are not intercepted by inlets to the streets or the detention pond. a. The swales are designed to convey 133% of the Q100 or the overflow depending on the location of the swale. b. All swales with slopes less than 0.02 ft./ft. (2.0%) will have a two foot (2') valley pan constructed with it. c. Sidewalk culverts or area inlets are provided at the downstream end of swales which convey runoff to streets. d. Typically the swales will have 4:1 (run:rise) side slopes except as noted. e. The rear lot swales are typically situated in ten foot (10� drainage and utility - easements located along the rear property line. These easements are designated on the final plat. = f. Metal sidewalk culverts are provided at the outfall of the swale to the street for sections A -A, C-C and D-D. An area inlet is provided at the outfall from section B-B. A pipe will convey the runoff from the swale to the proposed inlets on Seneca Street and then to the pond. 2. The tables below summarizes the design of the rear lot swales. These swales are designated A -A, B-B, C-C, D-D, J-J, and K-K on the Drainage and Erosion Control plan. Refer to page 18a in Appendix I for a complete summary. Design Top Design Flow Slope Depth Capacity Width Section Point cfs ft.f ft. cfs ft. A -A 5c 6.52 0.005 0.60 9.1 14.0 B-B 5a 6.73 0.008 0.60 11.1 14.0 C-C 5b 6.51 0.005 0.60 8.8 14.0 D-D 10a 6.68 0.005 0.60 8.8 9.0 J-J Bls 5.31 0.010 1.00 11.5 8.0 K-K B2 4.95 0.0167 0.75 6.9 6.0 Page 16 Final Drainage and Erosion Control Report Westfield Park P.U.D. IV DRAINAGE FACILM DESIGN C. Specific Details -Swales 3. The table below summarizes the design of the overflow swales. These swales are designated E-E, F-F and G-G.on the Drainage and Erosion Control.plan. Design Design Flow Slope Section Point cfs ft E-E 2 2.85 0.02 F-F OS 1 75.0 0.0133 G-G 3 59.44 0.02 D. Specific Details - Channel in Tract A Depth Capacity ft. cfs Outfall 0.75 11.01 Pond 1.5 117.89 Painted Desert Ct 1.5 69.89 Pond 1. The design flow for the channel is 179.8 cfs. This is based on the 100-year storm generated by the SWM model and includes all offsite flows from sub -basin OS2. 2. The channel section along the rear property lines of lots 6-9 has the following section and capacity. Refer to the Flow master print out in Appendix IV for the channel capacity calculations. Downstream of these lots the channel widens and steepens. Top Bottom Flow Channel Width Width Slope Capacity Depth Depth ft. ft. ft ft cfs ft. ft. 34 16 0.004 264 1.96 2.25 3. The peak 100-year flow at the upstream end of the box culvert was determined to be 179.8 cfs according to the SWM model. Therefore the channel is adequate. 4. A fifteen (15') foot drainage easement has been dedicated along the rear property lines of lots 1-9 due to the encroachment of 100-year flows onto the lots. This has been shown on the final plat. Page 17 ` Final Drainage and Erosion Control Report Westfield Park P.U.D. IV DRAINAGE FACII.M DESIGN E. Specific Details -streets The following tables summarize the 1/2 street capacities of local, collector and arterial streets at minimum slopes. The 2-year storm capacity is based on allowable flow depths at flowline the following equation: Qt =0.56 (Z/n) S" yen The 100-year storm capacity is based on allowable flow depths at flowline and Mannings equation using the smallest allowable slope. Refer to the attached exhibits in Appendix 1 for the source of the major storm flow capacities. The respective street widths for each street classification are as follows: Street Width Street flowline - flowline Classification feet Local 36 Collector 50 Arterial 70 2-year storm Street Allowable Designation flow depth theoretical 1/2 Reduction Allowable 1/2 (Street grade) ® flowline street capacity factor street capacity Local (0.50%) 0.45 14.7 cfs 0.65 9.5 cfs Collector (0.50%) 0.50 19.5 cfs 0.65 12.7 cfs Arterial (0.40%) 0.50 17.4 cfs 0.50 8.7 cfs 100-year storm Street Allowable Designation flow depth theoretical 1/2 Reduction Allowable 1/2 (Street grade) ® flowline street capacity factor street capacity Local (0.50%) 0.95' 65.5 cfs 0.65 42.6 cfs Collector (0.50%) 1.13' 99.3 cfs 0.65 64.6 cfs Arterial (0.40%) 1.33' 156.8 cfs 0.50 78.4 cfs 2. The theoretical half street capacity of West Horsetooth Road based on a flow depth up to the crown of the road (0.83' at flowline) and a slope of 0.4% is 28.63 cfs. The half street capacity is 14.31 cfs after the reduction factor is applied. The flows from Imperial Estates to West Horsetooth Road are conveyed to the Westfield Park P.U.D. via the proposed channel along the south side of West Horsetooth Road. Refer to page 1 of 1 in the Street section of the Drainage calculations located in Appendix I. Page 18 Final Drainage and Erosion Control Report Westfield Park P.U.D. l V DRAINAGE FACILITY DESIGN E. Specific Details -streets ( continued) 3. When flow depths on Seneca Street exceed 0.70 feet at the flowline the water will overflow into the pond or the eastern cul-de-sacs. The allowable flow depth at the flowline in Seneca Street is 1.13 feet The overall peak 100-year flow to the low point on Seneca Street between Corydalis and Ambrosia Courts is approximately 53.0 cfs (41.26+11.8). Refer to pages 6 and 7A in Appendix I. The allowable 1/2 street capacity for a collector like Seneca with a slope of 0.005 ft/ft is 64.6 cfs. Therefore the allowable flow depth in Seneca Street will not be exceeded during a 100-year event. V. EROSION CONTROL AND WATER QUALITY: A. General Concept 1. Erosion control measures are specified on the Drainage and Erosion Control plan. a. Maintenance of erosion control devices will remain the responsibility of the contractor and the owner until the project is complete. B. Specific Details 1. The following temporary erosion control measures are specified on the Drainage and Erosion Control plan: a. Area inlet filters composed of Haybales around all area inlets . b. Gravel inlet filters will be required at all storm sewer inlets. c. Haybale dikes within all channels. d. Silt Fence along all downstream property lines. 2. The following permanent erosion control measures are specified on the Drainage and Erosion Control Plan. a. Buried riprap aprons at all storm sewer outfalls b. Buried riprap on the bank on the east side of Seneca Street centered at station 0+92.00 and. 6+36.74. Limits of the riprap are specified on the Drainage and Erosion Control Plan. c. The soil of all open space shall be permanently stabilized with seed or sod according to generally accepted practices upon completion of final grading. 3. The erosion control measures will apply to each of the three phases. Page 19 Final Drainage and Erosion Control Report Westfield Park P.U.D. V. EROSION CONTROL AND WATER QUALITY: C. Water Quality ' .: 1. The required water quality capture volume is 1.05 feet. From the pond stage storage curve, this occurs at elevation 5096 feet. 2. A permanent water quality outlet for wet extended detention basins will be installed. Maintenance of this device will be required. A note to this effect is on the plans. Details are also provided on the plans. VI. EROSION CONTROL SECURITY DEPOSIT: An erosion control security deposit is required in accordance with City of Fort Collins policy (Chapter 7, Section C: SECURITY; page 7.23 of the City of Fort Collins Development Manual). In no instance shall the amount of the security be less than $ 1000.00. 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. 2. The erosion control security deposit amount required for each phase of Westfield Park P.U.D. will be paid paid prior to the commencement of each phase of construction. Three phases are expected. Refer to the Phasing plan for limits of each phase. A separate erosion control cost estimate has been prepared for each phase and is included in Appendix II. See the Erosion Control Security Deposit Requirements document for each phase located in Appendix H. 3. The erosion control security deposit is reimbursable. Page 20 Final Drainage and Erosion Control Report Westfield Park P.U.D. VII. VARIANCE FROM CITY STANDARDS A. Variance from City of Fort Collins Requirements 1. With this report, the developer is formally requesting a variance from: a. the requirement that one (Y) foot of freeboard be provided. 2. We have provided 0.97 feet of freeboard. Refer to the stage storage curve on page 1 of the Detention Pond calculations located in Appendix I. 3. We have provided 4.35 acre feet of excess volume in the pond. Refer to the stage storage curve on page 1 of the Detention Pond calculations located in Appendix L 4. We have provided detention for some offsite areas which historically contribute undetained flows to the site and to the South Shields Street storm sewer. B. Approval of this report represents an approval of this variance request by the City of Fort Collins. VIM CONCLUSIONS A. Compliance With Standards 1. The grading and drainage design for Westfield Park P.U.D. is in compliance with the City of Fort Collins storm drainage design criteria and the recommendations of a. Foothills Master Drainage Plan Update and Westfield Park P.U.D. Regional Detention Pond Analysis and b. SWMM Analysis and UDSEWER Analysis for Westfield Park P.U.D. Regional Detention Pond and Downstream Conveyance System. 2. The erosion control measures shown on the erosion control plan comply with the City of Fort Collins standards and generally accepted erosion control practices. B. Drainage Concept 1. The proposed drainage design for Westfield Park P.U.D. is effective for the control of storm runoff with a considerable reduction in potential downstream effects. . Page 21 Final Drainage and Erosion Control Report Westfield Park P.U.D. IX. REFERENCES 1. City of Fort Collins "Storm Drainage Design Criteria and Construction Standards'; May, 1984 2. City of Fort Collins "Erosion Control Reference Manual"; January, 1991 3. Foothills Basin (Basin G) Drainage Master plan; Resource Consultants, Inc.; February ,1981 4. Preliminary Drainage Report for Stockbridge P.U.D.; Land Development Services; April 4, 1994. ' 5. Final Design of Regional Detention Pond 247 and Outfall for the McClellands and Mail Creek Basin; RBD, Inc. Engineering Consultants; October 26, 1994 6. Foothills Master Drainage Plan Update and Westfield Park P.U.D. Regional Detention Pond Analysis; Prepared by Faucett Engineering Services; Dated April 9; 1997 APPENDIX I Drainage Calculations PEAK FLOWS ADDITIONAL REFERENCES Foothills Master Drainage Plan Update and Westfield Park P.U.D. Regional Detention Pond Analysis and SWMM Analysis and UDSEWER Analysis for Westfield Park P.U.D. Regional Detention Pond and Downstream Conveyance System For Peak flows to major on site conveyance elements PLOW SUMMARY FOR WESTFIRLD PARK PUD PAGE 1 , DESIGN CONTRIBUTING AREA C2 C10 C100 Tc Tc I2 I10 2100 Q2 Q10 Q100 DESIGN PAGE POINT SUB 2,10 100 BASIN(S) ac. min. min iph iph iph cfs cfs cfs rr rrrr:rr rr were++x++t♦+rrrrrrrr:rrr+rtrrx++rrrrrrrxr txxwx.+++++x rrrrxrw+++trrrte+++++rrrrrrr++++++r+++++++++r DEVELOPED PEAK PLOWS FOR STORM SEWER INFRASTRUCTURE' PROFILE A OS2 PLOWS CALCULATED BY SWMM 26.80 74.10 172.8 7 A7 2.51 0.62 0.62 0.78 13.50 13.50 2.26 3.96 6.38 3.52 6.16 12.42 I/P 8 6 A6 0.33 0.47 0.47 0.63 5.00 5.00 3.29 5.64 9.30 0.51 0.87 7.95 I/P 9 PROFILE B 5 A5 & OSS 10.83 0.47 0.47 0.59 15.00 15.00 2.14 3.75 6.06 10.89 19.09 38.56 I/P 6 4'A4 0.43 0.83 0.83 0.63 5.00 5.00 3.29 5.64 9.30 1.17 2.01 2.52 I/P 7 4 AS & OS5&A4 11.26 0.48 0.48 0.60 15.00 15.00 2.14 3.75 6.06 11.66 20.43 41.26 P 7A NOTE: PLOWS TO DP 5 DO NOT INCLUDE OVERFLOW FROM DP'S 9 & 10. REFER TO PAGES 1 & 2 OF 2 FOR THESE PLOWS INFRASTRUCTURE DESIGN _ DESIGN DESIGN DESIGN INLET PLOW INLET DESIGN Q100 POINT SIZE DEPTH CAPA- STORM DESIGN OVER CITY Q FLOW PT FT CPS YR CPS CPS tttrrrrrxxrxxerr+x+r++++trxrrx+rrrxrxr++•+++++r+ttxxtrrtrr PROFILE B Sa AREA INLET NA 1.00 5.06 100 5.06 0.00 5 INLET 15.00 1.03 33.75 10 16.58 11.55 4 INLET 10.00 1.03 21.25 100 2.01 0.00 PROFILE A 7 INLET 5.00 0.70 6.40 10 6.16 6.02 6 INLET 5.00 0.70 6.40 10 0.87 0.00 t ttrrtrrerrrrrrrrrrrrrrrttttr+ttxxrrrrrrrrrrrrttt txtttt+rtxxtxttttrrrrt t+t+rrrtrrt trtttt+xrrrrrrrrrrrrrr tr++ DESIGN DESIGN DESIGN PIPE MANN- PIPE PERI- HYD. CONV- SLOPE PIPE NUMBER PIPE NOTES POINT PLOW SIZE TYPE INGE AREA METER RAD -ANCB CAPA- OF CAPA- n PACT CITY PIPES CITY CPS PT SP F PT FT/PT CPS CPS •+++trrrrrrrrrrr+x+++++++++•++t+xtxrxrrrr++++++•t+tt+x++r+x+rtt+x+x++r++++xtxrrxrx+•+e+++t+rt+rt+xtrtrrxr+r+ PROFILE B SA PIPE 5.06 1.50 ADS 0.012 1.77 4.71 0.38.113.8 0.005 8.05 1 8.05 OK 5 PIPE 19.08 1.50 RCP 0.013 1.77 4.71 0.38 105.0 0.005 7.43 3 22.28 OK 4 PIPE 52.87 2.00 ADS 0.012 3.14 6.28 0.50 245.1 0.005 17.33 3 51.99 OK . PROFILE A 7 PIPE 6.4 1.25 RCP 0.013 1.23 3.93 0.31 64.6 0.100 20.43 OK 6 PIPE 6.4 1.25 RCP 0.013 1.23 3.93 0.31 64.6 0.100 20.43 OK l SUMMARY OF WESTFIELD PARK POO DRAINAGE BASINS RUNOFF COEFFICIE PAGE 2 IM- DATE: 06/10/97 SUB- PERVIOUS PERVIOUS BASIN OPEN ROADS ROOF/ LAWN C2 C100 SF ACRES SPACE DRIVES 0.20 0.95 0.95 0.20 +rrre+r+++r++++ffftrfffrffftrfffrtf tff: tef rexf txxrxr+r+++r+r+r+r++rf r+rtf:e t:tttr. Al 304927 7.00 5.33 0.00 0.50 1.17 0.25 0.32 A2 58482 1.34 0.00 0.44 0.27 0.63 0.60 0.75 ' A3 40169 0.92 0.00 0.23 0.21 0.48 0.56 0.69 A4 18517 0.43 0.00 0.33 0.03 0.07 0.83 1.00 - AS 393564 9.03 .0.00 1.52 2.25 5.26 0.51 0.64 A6 14499 0.33 0.00 0.03 0.09 0.21 0.47 0.59 A7 109336 2.51 0.00 0.94 0.47 1.10 0.62 0.78 A7a 119790 2.75 0.54 0.00 0.66 1.55 0.38 0.48 A9 58951 1.35 0.00 0.39 0.29 0.67 0.58 0.72 A10 159172 3.65 0.00 0.50 0.95 2.21 0.50 0.62 . All 6209 0.14 0.02 0.12 0.00 0.00 0.84 1.00 SUBTOTAL 830158 19.06 5.33 2.52 3.26 7.61 0.46 0.58 B1 87778 2.02 0.00 0.30 0.51 1.20 0.50 0.63 B2 41218 0.95 0.24 0.07 0.19 0.45 0.41 0.51 SUBTOTAL 128996 2.96 0.24 0.37 0.71 1.65 0.47 0.59 TOTAL 959154 22.02 5.57 2.89 3.97 9.26 0.46 0.58 OPPSITS BASINS OS-lall 872071 20.02 0.00 1.99 1.80 16.23 0.34 0.43 OS-2 2083039 47.82 0.00 4.38 4.34 39.10 0.34 0.42 OS-3 889060 20.41 5.03 1.93 1.35 12.11 0.32 0.40 OS-lpart 750103 17.22 0.00 1.99 1.52 13.71 0.35 0.44 SUBTOTAL 3844170 88.25 5.03 8.30 7.49 67.43 0.33 0.42 OFFSITE MINOR BASINS WHICH CONTRIBUTE DIRECTLY TO WESTFIELD PARK OS-Sa 8400 0.19 0.00 0.00 0.02 0.17 0.28 0.34 OS-5b 14000 0.32 0.00 0.00 0.03 0.29 0.28 0.34 OS-5 78000 1.79 0.00 0.00 0.18 1.61 0.28 0.34 OS-10a 8000 0.18 0.00 0.00 0.02 0.17 0.28 0.34 OS-10 16800 0.39 0.00 0.00 0.04 0.35 0.28 0.34 TOTAL 94800 2.18 0.00 0.00 0.22 1.96 0.29 0.34 OFFSITS MINORBASINS WHICH CONTRIBUTE DIRECTLY TO MOUNTAIN RIDGE OS-B1 11200 0.26 0.00 0.00 0.03 0.23 0.28 0.34 ON SITS MINOR BASINS Sa 61255 1.41 0.00 0.00 0.42 0.98 0.43 0.53 Sb 55800 1.28 0.00 0.00 0.38 0.90 0.43 0.53 Sc 42790 0.98 0.00 0.00 0.29 0.69 0.42 0.53 7a 119790 2.75 0.54 0.00 0.66 1.55 0.38 0.48 l0a 54873 1.26 0.00 - 0.00 0.3a 0.88 0.43 0.53 SUMMARY OF COMPOSITE RUNOFF COEFFICIENTS FOR DESIGN POINTS IN WESTFIELD PARK PUD PAGE 3 DESIGN CONTRIBUTING DATE: 06/10/97 POINT SOB - BASINS AREA ACRES C2 C100 DESIGN rrr•r+•+rrr+r+rrxr:+r+r+er•+rrr++r+xxxxr+r+r+r+r++r+r+r+xxxxxeexrr DESIGN POINTS FOR DETENTION PONDS 1 A & OS1 & OS2 97.31 0.38 0.47 DST POND +**+ DESIGN POINTS FOR STORM SEWER INFRASTRUCTURE & SWALE 2 A2 1.34 0.60 0.75 INLET/PIPS +• . 3 A3 0.92 0.56 0.69 INLET/PIPS ** 4 A4 0.43 0.83 1.00 INLET/PIPE +* 5 AS & OS5 10.83 0.47 0.59 INLET/PIPS +• Sa ASa & OSSa 1.60 0.41 0.51 SWALE 5b A5b & OS5b 1.60 0.39 0.49 SWALE Sc ASc 0.98 0.42 0.53 SWALE 6 A6 0.33 0.47 0.59 INLET/PIPS ** 7 A7 2.51 0.62 0.78 INLET/PIPS ** 7a A7a & OS2 50.57 0.34 0.42 SWALE/BOX CULVERT ### 9 A9 & OSlpart 18.57 0.37 0.46 INLET/PIPS ** 10 A10 &.OSIO 4.04 0.48 0.59 INLET/PIPS ** 10a A10a & OS10a 1.44 0.41 0.51 SWALE 11 All 0.14 0.84 1.00 INLET/PIPS OS1 OSlpart 17.22 0.35 0.44 INLET/PIPS/SWALE ** & *•* NOTES: * - INCLUDES FLAWS FROM REAR LOTS ALONG WEST PROPERTY LINE OF IMPERIAL ESTATES ** - INDICATES THAT INLET AND PIPS ARE SIZED FOR LESS THAN Q100 OVERFLOW INTO POND OR SWALE IS INCLUDED IN DESIGN *** - STREET CAPACITIES ARE EXPECTED TO HANDLE OVERFLOW +*++- REFER TO SWM MODEL FOR DETENTION POND SIZING ### - REFER TO SWM MODEL FOR FLAWS USED IN CHANNEL AND BOX CULVERT SIZING SHEAR ENGINEERING CORPORATION PAGE 4 SUBBASIN BREAKDOWN PROTECT: WESTFIELD PARK PUD DATE: 06/10/97 PROTECT NO 1005-44-94 BY HBO PROTECT LOCATION :WEST HORSBTOOTH ROAD FILE: WESTBAS PLATTED AREA OFFSITE AREA TO WEST IS IMPERIAL ESTATES STOCKBRIDGE 31.02 ACRES OS-1 20.02 ACRES OUTLOT 1.15 ACRES OS-2 47.82 ACRES TOTAL 32.17 ACRES TOTAL 67.84 ACRES OVERALL TOTAL 100.01 ACRES ASSUMPTIONS: SINGLE FAMILY LOTS 70% LAWN TO 30% IMPERVIOUS IM- SUB- PERVIOUS PERVIOUS BASIN OPEN ROADS ROOF/ LAWN C2 C100 SP ACRES SPACE DRIVES 0.20 0.95 0.95 0.20 lflfiffllf iflff if if kifflftlifflttff!lrlrffffflllr rr tff tf tttrrtt lr YfrYrfrrfrr rtf r! Al 304927 7.00 5.33 0.00 0.50 1.17 0.25 0.32 A2 58482 1.34 0.00 0.44 0.27 0.63 0.60 0.75 A3 40169 0.92 0.00 0.23 0.21 0.48 0.56 0.69 A4 18517 0.43 0.00 0.33 0.03 0.07 0.83 1.00 AS 393564 9.03 0.00 1.52 2.25 5.26 0.51 0.64 A6 14499 0.33 0.00 0.03 0.09 0.21 0.47 0.59 A7 109336 2.51 0.00 0.94 0.47 1.10 0.62 0.78 Ala 119790 2.75 0.54 0.00 0.66 1.55 0.38 0.48 A9 58951 1.35 0.00 0.39 0.29 0.67 0.58 0.72 A10 159172 3.65 0.00 0.50 0.95 2.21 0.50 0.62 All 6209 0.14 0.02 0.12 0.00 0.00 0.84 1.00 _ SUBTOTAL 1283616 29.47 5.89 4.50 5.72 13.35, 0.46 0.58 NOTE: SUBBASINS Al -All CONTRIBUTE RUNOFF DIRECTLY TO POND B1 87778 2.02 0.00 0.30 0.51 1.20 0.50 0.63 B2 41218 0.95 0.24 0.67 0.19 0.45 0.41 0.51 SUBTOTAL 128996 2.96 0.24 0.37 0.71 1.65 0.47 0.59 TOTAL 1412612 32.43 6.13 4.87 6.43 15.00 0.46 0.58 NOTE: BASINS B1 & B2 CONTRIBUTE RUNOFF TO THE PROPOSED MOUNTAIN RIDGE SUBDIVISION OFFSITE BASINS & SUB -BASINS IM PERVIOUS PERVIOUS BASIN OPEN ROADS ROOF/ LAWN C2 C100 SPACE DRIVES SF ACRES 0.20 0.95 i 0.95 0.20 r rerrrt+tt+tf+fiifrt tertttf++++++i+fittfiff+ftftlff trrtlrrtr rr rftrrrrrrrrrrrlrf:r OS-lall 872071 20.02 0.00 1.99 1.80 16.23 0.34 0.43 OS-2 20a3O39 47.82 0.00 4.38 4.34 39.10 0.34 0.42 OS-3 889060 20.41 5.03 1.93 1.35 12.11 0.32 0.40 ` SUBTOTAL 3844170 88.25 5.03 8.30 7.49 67.43 0.33 0.42 TOTAL 4238726 97.31 5.89 10.87 11.87 68.68 0.38 0.47 NOTE: TOTAL DOES NOT INCLUDE SUB -BASIN OS-3 OR SUB -BASINS B1 AND B2 TOTAL IS AREA CONTRIBUTING RUNOFF TO THE REGIONAL POND SHEAR ENGINEERING CORPORATION PAGE 5 SUBBASIN BREAKDOWN WESTFIELD PARK PUD. DATE: 07/29/97 PROJECT: 10OS-44-94 BY HBO PROJECT NO WEST HORSETOOTH ROAD PILE: WESTBAS PROJECT LOCATION IM- SUB- PERVIOUS PERVIOUS BASIN OPEN ROADS ROOF/ LAWN C2 C100 _ SF ACRES SPACE DRIVES 0.20 0.95 0.95 0.20 frfl++f+ffrffftetreltlf+rfffrf rff tff+1tf 111frtr trrl++rrf tf re tftlrffrf+11tr1t+lrrrllf tr+re# OS-Sa 8400 0.19 0.00 0.00 0.02 0.17 0.28 0.34 OS-Sb 14000 0.32 0.00 0.00 0.03 0.29 0.28 0.34 OS-5 78000 1.79 0.00 0.00 0.18 1.61 0.28 0.34 OS-10a 8000 0.18 0.00 0.00 0.02 0.17 0.28 0.34 OS-10 16800 0.39 0.00 0.00 0.04 0.35 0.28 0.34 OS-B1 11200 0.26 0.00 0.00 0.03 0.23 0.28 0.34 TOTAL 136400 3.13 0.00 0.00 0.31 2.82 0.28 0.34 OS-lpart 17.22 0.00 1.99 1.52 13.71 0.35 0.44 17.22 TOTAL CONTRIBUTING AREA TO PROPOSED INLET AT EASTERN TERMINUS OF IMPERIAL DRIVE IM- PERVIOUS PERVIOUS MINOR OPEN ROADS ROOF/ LAWN C2 C100 BASIN SPACE DRIVES SF ACRES 0.20 0.95 0.95 0.20 llflf11f1f tff!!lflft#1111f11f1f 11t1f##fY#Yf#rt111!ll+f YffY+fff tfltYf if lff+llff!!f Sa 61255 1.41 0.00 0.00 0.42 0.98 0.43 0.53 5b 55800 1.28 0.00 0.00 0.38 0.90 0.43 0.53 _ Sc 42790 0.98 0.00 0.00 0.29 0.69 0.42 0.53 7a 119790 2.75 0.54 0.00 0.66 1.55 0.38 0.48 10a 54873 1.26 10.00 0.00 0.38 0.88 0.43 0.63 OS-1 DRAINS DIRECTLY TO WESTFIELD PARK POD ® SEVERAL LOCATIONS OS-2 DRAINS TO HORSETOOTH ROAD AND PLOWS EAST OS-3 DRAINS TO ROSSBOROUGH PILING 3 ASSUMPTIONS: LARGE SINGLE FAMILY LOTS 90% LAWN AND 10% ROOF & DRIVE SHEAR ENGINEERING CORPORATION PAGE 6 PLOW TO CONCENTRATION POINT 5 FROM SUB -BASINS AS & OSS PROTECT: WESTFIELD PARK PUD DATE 10/07/97 LOCATION:PORT COLLINS PRO7. NO.1005-44-94 PILE: WBSTRAT BY HBO NOTES: PEAK PLOW TO LOW POINT ON WEST SIDE OF SBNBCA BETWEEN CORYDALIS AND AMBROSIA COUR ABOVE 0.70 PERT AT THE PLOWLINS THE WATER OVERFLOWS INTO THE POND AREA (A)= 10.830 ACRES RUNOFF COEF. (C) 2 YEAR 10 YEAR 100 YEAR C 0.47 0.47 0.59 SEE SPREAD SHEET ATTACHED ON PAGE 3 TIME OF CONCENTRATION (Tc) OVERLAND TRAVEL TIME (Ti) LENGTH . 140 PERT SLOPE 1.00 t 2 YEAR 10 YEAR 100 YEAR C 0.20 0.20 0.25 Ti (min)- 19.91 19.91 18.81 TRAVEL TIME (TO =L/(60*V) PLOW TYPE L (ft) = 260 S (t) = 2.00 SWALE V (fps) = 2.16 Tt(min)= 1.23 L (ft) = 650 S (t) = 2.00 GUITAR V (fps) = 2.00 Tt(min)= 5.42 L (ft) =7 S (t) = 0 HOME V (fps) = 0.00 Tt(min)= 0.00 L (ft) =7 S (t) = 0 NONE V (fpe),= 0.00 Tt(min)= 0.00 L (ft) =7 S (t) - O NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) =7 S (t) = 0 NONE V (fps) _ 0.00 Tt(min)= 0.00 L (ft) =7 S (t) = 0 NONE V (fps) = 0.00 Tt(min)= 0.00 ALL VBLOCITISS TAKEN FROM FIGURE 3-2 TOTAL TRAVEL TIME (min) = 6.65 TOTAL_LENGTH = 950 L/180+10= 15.28 < 25.46 Tc =Ti+TOTAL TRAVEL TIME 2 YEAR 10 YEAR 100 YEAR Tc (min)= 15.2E 15.28 15.28 USE Tc = IS 15 15 INTENSITY (I) (iph) 2 YEAR 10 YEAR 100 YEAR I = 2.14 3.75 6.06 NOTE: INTENSITIES TAKEN FROM FIGURE 3-1 WHEN PLOW DEPTH EXCEEDS 0.7 FEET DEEP ® FLOWLINE IT WILL SPILL INTO POND RUNOFF (Q= CIA) (cfe) 2 YEAR 10 YEAR 100 YEAR Qinlet = 10.89 19.09 38.56 Qeouth = 0.00 0.00 11.80 OVERFLOW FROM DP'S 9 & 10 Qtotal = 10.89 19.09 50.36 TOTAL PLOW TO INLET Qpipe = 1.43 2.51 5.06 FROM MINOR BASIN Asa IN PIPE Qinlet = 9.46 16.58 45.30 Qtotal - Qpipe Qover = 0.00 0.00 11.55 OVERFLOWS TO EAST SIDE OF STREET CONCLUDB:INSTALL 15 TYPE R INLET IN SUMP CONDITION -SIZED FOR 10 YR EVENT HEIGHT OF OPENING (h) (ft). 0.50 FLOW DEPTH ® PL.OWLINE (Yo) (ft) = 1.03 Yo/h (ft) = 2.06 CAPACITY PER LF = 2.50 CFS/LF - PIG 5-2 THEORETICAL CAPACITY = 37.50 FT. REDUCTION FACTOR = 90.00% ACTUAL CAPACITY = 33.75 CPS OK SHEAR ENGINEERING CORPORATION PAGE 7 FLOW TO CONCENTRATION POINT 4 FROM SUB -BASIN A4 PROJECT: WESTFIELD PARK PUD DATE 10/07/97 LOCATION:FORT COLLINS PROD. NO.1005-44-94 FILE: WBSTRAT - BY MEO NOTES: INLET AT LOW POINT ON EAST SIDE OF SBNECA BETWEEN AMBROSIA AND CORYDALIS COURTS ABOVE 0.70 PERT AT THE FLOWLINE THE WATER OVERFLOWS INTO THE POND AREA (A)= 0.430 ACRES RUNOFF COEF. (C) 2 YEAR 10 YEAR 100 YEAR C = 0.83 0.83 0.63 SEE SPREAD SHEET ATTACHED ON PAGE 3 TIME OF CONCENTRATION (TO OVERLAND TRAVEL TIME (Ti) LENGTH -RA FEET SLOPE =MA IF 2 YEAR 10 YEAR 100 YEAR C = 0.20 0.20 0.25 Ti (min)- 0.00 0.00 0.00 TRAVEL TIME (Tt)=L/(60*V) FLOW TYPE L (ft) - 163 S (4) - 0.8 GUTTER V (fps) - 1.80 Tt(min)- 1.51 L (ft) - 90 S (k) = 0.7 GUTTER V.(fps) - 1.72 Tt(min)- 0.87 L (ft) 38 S (3) = 0.5 GUTTER V (fps) - 1.50 Tt(min)- 0.42 L (ft) =7 S (t) = 0 NONE V (fps) - 0.00 Tt(min)- 0.00 L (ft) _? S (%) = 0 NONE V (fps) - 0.00 Tt(min)- "0.00 L (ft) =7 S (4) = 0 NONE V (fps) - 0.00 Tt(min)= 0.00 L (ft) _? S (►) = 0 NONE V (fps) - 0.00 Tt(min)- 0.00 ALL VELOCITIES TAKEN FROM FIGURE 3-2 TOTAL TRAVEL TIME (min) = 2:80 TOTAL LENGTH = 291 L/180+10- 11.62 > 2.80 CHOOSE LESSER Tc -Ti+TOTAL TRAVEL TIME 2 YEAR 10 YEAR 100 YEAR Tc (min)= 2.80 2.80 2.80 USE Tc - 5 5 5 INTENSITY (I) (iph) 2 YEAR 10 YEAR 100 YEAR I 3.29 5.64 9.30 NOTE: INTENSITIES TAKEN FROM FIGURE 3-1 RUNOFF (Q= CIA) (cfe) 2 YEAR 10 YEAR 100 YEAR Qinlet = 1.17 2.01 2.52 Qover 0.00 0.00 ll.55 FLOWS OVERTOPPING SENECA FROM WEST Qtotal = 1.27 2.01 14.07 TOTAL FLOW TO INLET Qoverp = 0.00 0.00 0.00 OVERFLOW TO POND CONCLUDE:INSTALL 10 ' TYPE R INLET IN SUMP CONDITION -SIZED FOR 100 YR EVENT HEIGHT OF OPENING (h) (ft)= 0.50 FLOW DEPTH ® FLOWLINE (Yo) (ft) - 1.03 Yo/h = 2.06 CAPACITY PER LP = 2.50 CFS/LP FROM FIG 5-2 THEORETICAL CAPACITY = 25.00 FT. REDUCTION FACTOR = 85.00% ACTUAL CAPACITY = 21.25 CPS > Q100 OK WHEN FLOW DEPTH EXCEEDS 0.7 FEET DEEP IT WILL SPILL INTO POND SHEAR ENGINEERING CORPORATION PAGE 7A PLOW'TO CONCENTRATION POINT 4 FROM SUB -BASINS AS & OSS&A4 PROJECT: WESTFIELD PARK PUD DATE 10/07/97 LOCATION:PORT COLLINS PROD. NO.1005-44-94 PILE: WESTRAT BY MHO ' NOTES: PEAK FLOW TO LOW POINT ON WEST SIDE OF SENECA BRTWEEN CORYDALIS AND AMBROSIA ABOVE 0.70 DEBT AT THE PLOWLINE THE WATER OVERFLOWS INTO THE POND AREA (A)= 11.260 ACRES RUNOFF CORP. (C) 2 YEAR 10 YEAR 100 YEAR C 0.48 0.48 0.60 SEE SPREAD SHEET ATTACHED ON PAGE 3 TIME OF CONCENTRATION (Tc) OVERLAND TRAVEL TIME (Ti) LENGTH = 140 FEET SLOPE = 1.00 i 2 YEAR 10 YEAR 100 YEAR C 0.20 0.20 0.25 Ti (min)= 19.91 19.91 18.81 TRAVEL TIME (Tt) =L/(60*V) PLOW TYPE _ L (ft) = 160 S 2.00 SWALE V (fps) = 2.26 Tt(min)= 1.23 L (ft) 650 S (t) - 1.00 GUTTER V (fps) = 2.00 Tt(min)= 5.42 L (ft) _? S (t) - 0 NONE' V (fps) = 0.00 Tt(min)= 0.00 L (ft) _? S (t) = 0 NONE V (fps) 0.00 Tt(min)= 0.00 L (ft) _? S M - 0 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) _? S M = 0 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) _? S M = 0 NONE V (fps) = 0.00 Tt(min)= 0.00 ALL VELOCITIES TAKEN FROM FIGURE 3-2 TOTAL TRAVEL TIME (min) = 6.65 TOTAL LENGTH = 950 L/180+10- 15.28 < 25.46 . Tc =Ti+TOTAL TRAVEL TIME 2 YEAR 10 YEAR 100 YEAR Tc (min)- 15.28 15.28 15.28 USE Tc 15 IS 15 INTENSITY (I) (iph) 2 YEAR 10 YEAR 100 YEAR I = 2.14 3.75 6.06 NOTE: INTENSITIES TAKEN FROM FIGURE 3-1 WHEN PLOW DEPTH EXCEEDS 0.7 FEET DEEP M FLOWLINE IT WILL SPILL INTO POND RUNOFF (Q= CIA) (cfs) 2 YEAR 10 YEAR 100 YEAR Qtotal - 11.66 20.43 41.26 QintSa = 1.43 2.51 5.06 QintS = 9.46 16.58 33.75 Qint4 = 1.17 2.01 14.07 Qpipes = 12.07 21.10 52.88 CONCLUDE:SIZS PIPES FOR 200 -YEAR STORM Q10 - 52.88 CPS PIPE SIZE - 2.00 FOOT - ADS N-12 PIPE MANNINGS n - 0.012 CONVEYANCE FACTOR (C) - 245.08 C - (1.486*A*R"2/3)/n RSPER TO TABLE 5 NO. OF PIPES = 3 SLOPE (s)= 0.005 PT/PT CPS CAPACITY - CB"0.5= 17.33 CPS MULTIPLE PIPES - 51.99 OK PRESSURE PLOW SHEAR ENGINEERING CORPORATION PAGE 8 FLOW TO CONCENTRATION POINT 7 FROM SUB -BASIN A7 PROJECT: WESTFIELD PARK PUD DATE 06/10/97 LOCATION:FORT COLLINS PROJ. NO.1005-44-94 FILE: WESTRAT BY HBO NOTES: PEAK FLOW TO INLET ON WEST SIDE ON SENECA AT INTERSECTION WITH HORSETOOTH DOES NOT INCLUDE SUB -BASIN A7a WHICH CONVEYS RUNOFF TO CHANNEL AREA (A)= 2.510 ACRES RUNOFF COBF. (C) 2 YEAR 10 YEAR 100 YEAR - C = 0.62 0.62 0.78 SEE SPREAD SHEET ATTACHED ON PAGE 3 TIME OF CONCENTRATION (Tc) OVERLAND TRAVEL TIME (Ti) LENGTH = 70 FEET SLOPS = 4.00 4; 2 YEAR 10 YEAR 100 YEAR C = 0.20 0.20 0.25 Ti (min)= 8.91 8.91 8.42 TRAVEL TIME (Tt)-L/(60*V) FLOW TYPE L (ft) = 100 S (t,) = 2.5 SWALE V (fps) = 2.39 Tt(min)= 0.70 L (ft) = 100 S M - 0.5 GUTTER V (fps) = 1.50 Tt(min)= 1.11 L (ft) - 268 S (14) - 1.0 GUTTER V (fps) = 2.00 Tt(min)= 2.23 L (ft) = 65 S M - 0.5 GUTTER V (fps) = 1.50 Tt(min)= 0.72 L (ft) = 147 S (!) = 1.0 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) = S 00 = 0.0 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) = S (U) - 0.0 NONE V (fps) = 0.00 Tt(min)= 0.00 ALL VELOCITIES TAKEN FROM FIGURE 3-2 TOTAL TRAVEL TIME (min) = 4.76 TOTAL LENGTH - 750 L/180+10= 14.17 > 13.68 Tc =Ti+TOTAL TRAVEL TIME 2 YEAR 10 YEAR 100 YEAR Tc (min)= 13.68 13.68 13.18 USE Tc = 13.5 13.5 13.5 INTENSITY (I) (iph) 2 YEAR 10 YEAR 100 YEAR I = 2.26 3.96 6.38 NOTE: INTENSITIES TAKEN FROM FIGURE 3-1 RUNOFF (Q= CIA) (cfs) 2 YEAR - 10 YEAR 100 YEAR - Q = 3.52 6.16 12.42 Qover = 0.00 0.00 6.02 CONCLUDE:INSTALL 5 ' TYPE R INLET IN SUMP SIZED FOR 10 YEAR EVENT HEIGHT OF OPENING (h) (ft)= 0.50 DEPTH ® FLOWLINS (Yo)(ft) = 0.70 Yo/h = 1.40 ABOVE 0.70 FEET AT THE FLOWLINE THE WATER OVERFLOWS INTO THE POND CAPACITY PER LF = 1.60 CPS/LF FROM FIG 5-2 THEORETICAL CAPACITY = 8.00 FT. REDUCTION FACTOR = 80.0Oi ACTUAL CAPACITY = 6.40 CPS>Q10 = 6.16 CPS OK SOME OVERFLOW WILL BE INTERCEPTED BY INLET ON EAST SIDE OF SENECA ( DP 6) SHEAR ENGINEERING CORPORATION PAGE FLOW TO CONCENTRATION POINT 6 FROM SUB -BASIN A6 PROJECT: WESTFIELD PARK.PUD DATE 06/10/97 LOCATION:FORT COLLINS PRAT. NO.3005-44-94 FILE: WESTRAT BY MBO NOTES: PEAK PLOW TO PROPOSED INLET ON EAST SIDE OF SENECA 0 HORSETOOTH AREA (A)= 0.330 ACRES RUNOFF COSF. (C) 2 YEAR 10 YEAR 100 YEAR C = 0.47 0.47 0.63 SEE SPREAD SHEET ATTACHED ON PAGE 3 TIME OF CONCENTRATION (TO OVERLAND TRAVEL TIME (Ti) LENGTH =NA FRET SLOPE -HA tr 2 YEAR 10 YEAR 100 YEAR C = 0.20 0.20 0.25 Ti (min)= 0.00 0.00 0.00 9 TRAVEL TIME (TO ' =L/(60*V) FLOW TYPE. L (ft) = 163 3 (it) = 0.8 GUTTER V (fps) = 1.80 Tt(min)= 1.51 L (ft) - 90 S (4) = 0.7 GUTTER V (fps) = 1.72 Tt(min)= 0.87 L (ft) - 38 S (i) = 0.5 GUTTER V (fps) = 1.50 Tt(min)= 0.42 L (ft) _? S (4) = 0 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) _? S (i) = 0 NONE V (fps) 0.00 Tt(min)= 0.00 L (ft) _? S (t) = 0 NONE V (fps) = 0.00 Tt(min)- 0.00 ,. L (ft) =? S ('k) _ 0 NONE V (fps) = 0.00 Tt(min)- 0.00 .. ALL VELOCITIES TAKEN FROM FIGURE 3-2 TOTAL TRAVEL TIME (min) = 2.80 TOTAL LENGTH = 291 L/180+10= 11.62 > 2.80 CHOOSE LESSER Tc =Ti+TOTAL TRAVEL TIME 2 YEAR 10 YEAR 100 YEAR .. Tc (min). 2.80 2.80 2.80 _ USE Tc 5 5 5 INTENSITY (I) (iph) ., 2 YEAR 10 YEAR 100 YEAR I 3.29 5.64 9.30 ' NOTE: INTENSITIES TAKEN FROM FIGURE 3-1 RUNOFF (Q= CIA) (cfa) 2 YEAR 10 YEAR 100 YEAR Q = 0.51 0.87 1.93 Qwest = 0.00 0.00 6.02 Qt0tal = 0.51 0.87 7.95 Qover = 0.00 0.00 1.55 CONCLUDE:INSTALL 5 TYPE R INLET IN SUMP CONDITION -SIZED FOR 10 YR EVENT HEIGHT OF OPENING (h) 0.50 FT , FLOW DEPTH 0 FLOWLINS (Yo)- 0.70 FT - Yo/h = 1.40 _ ABOVE 0.70 FEET AT THE PLOWLINE THE WATER OVERFLOWS INTO THE POND CAPACITY PER LF =. 1.60 CFS/LF FROM FIG 5-2 THEORETICAL CAPACITY = 8.00 FT. REDUCTION FACTOR = 80.001, ACTUAL CAPACITY = 6.40 CPS> 0.87 CPS OK h FLOW SUMMARY FOR WESTFIELD PARK PUD PAGE 10 DESIGN CONTRIBUTING AREA C2 C10 C100 Tc Tc I2 I10 I100 Q2 010 Q100 DESIGNPAGB POINT SUB 2,10 100 BASIN(S) ac. min. min iph iph iph cfe cfe cfe r rrrrr:rrrr:ert+++xrerr trttrttrr rxe rrtttrr rrxx:rrrt tt+rrrrx: rerxxxrx tr+rrrtt++rx:rrr+mere rrr•+x:rerrtr tt tetr DESIGN FLOWS FOR STORM SEWER INFRASTRUCTURE PROFILE PAINTED DESERT COURT OS1 O81 FLOWS CALCULATED BY SWMM 11.10 NC 75.00 16 9 A9 1.35 0.37 0.37 0.46 39.00 39.00 1.22 2.23 3.64 0.61 1.11 33.05 I/P 11 10 A10 & OS10 - 4.04 0.48 0.48 0.60 39.00 39.00 1.22 2.23 3.64 2.37 4.32 39.61 I/P 12 9 & 10 A9-10,OS10 5.39 0.45 0.45 0.57 39.00 39.00 1.22 2.23 3.64 2.98 5.43 72.66 I/P/ST 13 3 A3a11 0.92 0.56 0.56 0.70 41.00 41.00 1.18 2.16 3.54 0.61 1.11 2.28 I/P/SW 14 PROFILE C 2 A2 1.34 0.60 0.60 0.75 12.00 12.00 2.38 4.17 6.71 1.91 3.35 6.74 I/P/SW 15 PROFILE D 11 All 0.14 0.84 0.84 1.00 5.00 5.00 3.29 5.64 9.30 0.39 0.66 1.30 I/P 17 HE: PAINTED DESERT COURT FLOWS INCLUDE THE OVERFLOW FROM IMPERIAL. SEE PAGES 11 14 IN REPORT FOR THESE OVERALL FLOWS INFRASTRUCTURE DESIGN DESIGN DESIGN INLET FLOW INLET Q100 Q100 POINT SIZE DEPTH CAPA- INLET OVER CITY FLOW PT FT CPS CPS CPS ++xrxxrrxrrrrr+tr rrrrxrrerrrrr trrr+xxxrrx: rx tt ttr+r:x xxx PROFILE PAINTED DESERT COURT 9 INLET 5.00 0.76 7.00 33.05 SEE OVERFLOW MODEL ON PAGES 1 AND 2 OF 2 10 INLET & PIPE y 5.00 0.76 7.00 39.61 SEE OVERFLOW MODEL ON PAGES 1 AND 2 OF 2 3 INLET & PIPE 5.00 0.50 4.52 49.21 44.68 OVERFLOW SWALE REQUIRED PROFILE C 2 INLET 5.00 0.50 4.60 6.71 2.14 OVERFLOW SWALE REQUIRED PROFILE D 11 INLET 5.00 0.76 7.00 1.30 0.00 - DESIGN DESIGN DESIGN PIPE MANN- PIPE PERI- HYD. CONY- SLOPE PIPE POINT FLOW SIZE TYPE INGE AREA METER RAD PACT CAPA- n A P R CITY CPS PT SP F PT FT/FT CPS xxrrx rretrr rrxrxrrr t+rerrrrrrrx:e+xxrrrrrrxxr:rrtr+rrrrr rxrxrxyrrrrxxxxtrrxxxxrrrxrr+r PROFILE PAINTED DESERT COURT 9 PIPE 1.11 1.50 RCP 0.013 1.77 4.71 0.38 105.0 0.040 20.90 10 PIPE 4.32 1.50 RCP 0.013 1.77 4.71 0.38 105.0 0.005 7.43 9 & 10 PIPE 1.11 24X38 BRCP 0.013 NC NC NC 421.0 0.005 29.77 3 PIPE 5.63 24X38 BRCP 0.013 NC NC NC 421.0 0.005 29.77 , PROFILE C 2 PIPE 3.35 1.25 ADS 0.012 1.23 3.93 0.31 70.0 0.010 7.00 PROFILE D 11 PIPE 1.30 1.25 ADS 0.012 1.23 3.93 0.31 69.98 0.01 7.00 N.B. 24 X 38 BRCP WILL BE FLOWING UNDER PRESSURE FROM DP 3 TO POND REFER TO HGL ON STORM SEWER PROFILE AND UD SEWER ANALYSIS CONVEYANCE FACTOR = 1.486*A*R"2/3/n REFER TO TABLES 4 & 5 IN APPENDIX III ADS - ADS N-12 PIPE ALL PIPE CAPACITIES ARE BASED ON MANNINGS EQUATION FOR PIPE FLOWING FULL (HW/D-1.0) OVERFLOW SWALE SUMMARY FOR WESTFIELD PARK PUD SECTION DESIGN SLOPE n DEPTH BOTTOM SIDE AREA HYD. Qcap Qdee FLOW POINT WIDTH SLOPE A RADIOS DEPTH t ft ft H:1 R-2/3 cfe cfe ft ' ♦trr tt+trvev rerrrrrtt tt♦sterrrtrrtt+tv+rr re vrrtrrtrrt+t+trrtrrttr+tt+e+ette+t +++r+r+++rtt++r rr rt r+t++r tttttt E-E 2 2.00 0.032 0.75 1.00 4.00 3.00 0.5586 11.01 2.85 0.42 G-G 3 2.00 0.032 1.50 2.00 4.00 12.00 0.8868 69.89 59.44 1.40 F-P O81 1.33% 0.024 1.50 8.00 4.00 17.45 0.9570 117.69. 75.00 NA NOTE: Qdee a 1.33*Qover DURING 100-YEAR EVENT 0 DESIGN POINT _ FLOW DEPTH = DEPTH OF FLOW FOR DESIGN FLOW DESIGN FLAW AT OS1 IS THE Q100 DETERMINED IN THE SWM MODEL. SHEAR ENGINEERING CORPORATION PAGE 11 FLOW TO CONCENTRATION POINT 9 FROM SUB -BASIN A9 PROJECT: WESTFIELD PARK PUD DATE 07/29/97 LOCATION:FORT COLLINS PROD. NO.1005-44-94 FILE: WBSTRUN BY MEO INLET AT NORTHWEST PCR OF PAINTED DESERT COURT AREA (A)= 1.350 ACRES RUNOFF COSP. (C) - 2 YEAR 10 YEAR 100 YEAR C = 0.37 0.37 0.46 SEE SPREAD SHEET ATTACHED ON PAGE 3 TIME OF CONCENTRATION (Tc) OVERLAND TRAVEL TIME (Ti) LENGTH =na FEET SLOPE -na 4 2 YEAR 10 YEAR 100 YEAR C = 0.20 0.20 0.25 Ti (min)= 31.00 31.00 31.00 To TO OS1 FROM SWMM TRAVEL TIME (Tt)-L/(60*V) FLOW TYPE L (ft) - 160 S (k) = 2.00 SWALE V (fps) = 2.16 Tt(min)= 1.23 L (ft) = 100 S (i) - 0.50 GUTTER V (fps) - 1.50 Tt(min)= 1.11 L (ft) = 690 S (%) = 1.00 GUTTER V (fps) = 2.00 Tt(min)- 5.75 L (ft) _? S 00 - 0.00 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) =7 S (i) - 0.00 NONE V (fps) = 0.00 Tt(min)- 0.00 L (ft) =7 S (_) = 0.00 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) =7 S M = 0.00 NONE V (fps) = 0.00 Tt(min)= 0.00 ALL VELOCITIES TAKEN FROM FIGURE 3-2 TOTAL TRAVEL TIME (min) = 8.10 TOTAL LENGTH = 950 L/180+10= 15.28 < 39.10 Tc =Ti+TOTAL TRAVEL TIME 2 YEAR 10 YEAR 100 YEAR Tc (min)= 39.10 39.10 39.10 USE Ti FROM SWMM AND ADD Tt USE Tc = 39 39 39 INTENSITY (I) (iph) 2 YEAR 10 YEAR 100 YEAR I 1.22 2.23 3.64 NOTE: INTENSITIES TAKEN FROM FIGURE 3-1 RUNOFF (Q= CIA) (cfe) 2 YEAR Qdirect = 0.61 1/2Qover= 0.00 Qtotal - 0.61 CONCLUDE:INLET FLOW DEPTH (Yo) _ CAPACITY/LF = REFER TO FIGURE 5-2 INLET SIZE _ INLET CAPACITY = CAPACITY = 100-YEAR OVERFLOW- 13.12 FLOW INTERCEPTED BY INLET AT IMPERIAL DRIVE 10 YEAR 100 YEAR 1.11 2.27 direct flow from A9 0.00 30.78 1/2 the overflow from imperial 1.11 33.05 added 1/2 overflow from area inlet PIPE SIZE - 1.50 FEET 0.76 ft PIPS TYPE - RCP 1.75 cfe DESIGN SLOPE = 0.50E DESIGN CAPACITY = 7.43 CPS 5 ft 7.00 cfe INCLUDES REDUCTION FACTOR FOR INLETS 7.00 > Q10inlet= 1.11 OK 26.05 cfe. WHICH OVERFLOWS SENECA STREET TO POND SHEAR ENGINEERING CORPORATION PAGE 12 FLOW TO CONCENTRATION POINT 10 FROM SUB -BASIN A10 & OS10 PROJECT: WESTFIELD PARK PUD DATE OS/30/97 LOCATION:FORT COLLINS PROJ. NO.1005-44-94 FILE: WBSTRUN BY MEO INLET AT SOUTHWEST PCR OF PAINTED DESERT COURT AREA (A)- 4.040 ACRES RUNOFF COHF. (C) 2 YEAR 10 YEAR 100 YEAR C = 0.48 0.48 0.60 SHE SPREAD SHEET ATTACHED ON PAGE 3 TIME OF CONCENTRATION (Tc) OVERLAND TRAVEL TIME (Ti) LENGTH =na FEET SLOPE -na IF 2 YEAR 10 YEAR 100 YEAR C = 0.20 .0.20 0.25 Ti (min)- 31.00 31.00 31.00 Tc TO OSS FROM SWMM TRAVEL TIME (Tt) =L/(60*V) FLOW TYPE. L (ft) = 160 S (t) - 2.00 SWALE V (fps) = 2.16 Tt(min)= 1.23 L (ft) = 100 S (t) - 0.50 GUTTER V (fps) = 1.50 Tt(min)= 1.11 L (ft) - 690 S (t) = 1.00 GUTTER V (fps) = 2.00 Tt(min)= 5.75 L (ft) _? S (t) - 0.00 NONE V (fps) = 0.00 Tt(min)= 0.00 L (£t) _? S (t) - 0.00 NONE V (fps) - 0.00 Tt(min)= 0.00 L (ft) _? S (t) - 0.00 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) _? S (t) - 0.00 NONE V (fps) - 0.00 Tt(min)= 0.00 ALL VELOCITIES TAKEN FROM FIGURE 3-2 TOTAL TRAVEL TIME (min) = 8.10 TOTAL LENGTH = 950 L/180+10= 15.28 < 39.10 Tc -Ti+TOTAL TRAVEL TIME 2 YEAR 10 YEAR 100 YEAR Tc (min)- 39.10 39.10 39.10 USE Ti FROM SWMM AND ADD Tt USE Tc = 39 39 39 INTENSITY (I) (iph) 2 YEAR 10 YEAR I = 1.22 2.23 NOTE: INTENSITIES TAKEN FROM FIGURE RUNOFF (Q= CIA) (cfe) 2 YEAR 10 YEAR Qdirect = 2.37 4.32 1/2Qover= 0.00 0.00 Qtotal = 2.37 4.32 100 YEAR 3.64 3-1 100 YEAR 8.83 direct flow from A10 30.78 1/2 the overflow from imperial 39.61 added 1/2 overflow from area inlet CONCLUDE:INLRT PIPE SIZE - 1.50 FEET FLAW DEPTH (Yo) = 0.76 ft PIPE TYPE - RCP CAPACITY/LF = 1.75 cfe DESIGN SLOPE = 3.961k , REFER TO FIGURE 5-2 DESIGN CAPACITY = 20.90 CPS OK INLET SIZE _ 5 ft INLET CAPACITY = 7.00 cfe INCLUDES REDUCTION FACTOR FOR INLETS CAPACITY 7.00 > Q10inlet= 4.32 OK 100-YEAR OVERFLOW- 32.61 cfe. OVERFLOWS SENECA STREET TO POND SHEAR ENGINEERINGCORPORATION PAGE 13 FLOW TO CONCENTRATION POINT 9 & 10 FROM SUB -BASIN A9-10,OS10 PROJECT: WESTFIELD PARK PUD DATE 05/30/97 LOCATION:FORT COLLINS PROJ. NO.1005-44-94 FILE: WESTRUN BY MEO AREA (A)= 5.390 ACRES RUNOFF COEF. (C) 2 YEAR 10 YEAR 100 YEAR C 0.45 0.45 0.57 SSE SPREAD SHEET AT ON PAGE 2 TIME OF CONCENTRATION (Tc) OVERLAND TRAVEL TIME (Ti) LENGTH -na FEET SLOPE -na % 2 YEAR 10 YEAR 100 YEAR C = 0.20 0.20 0.25 Ti (min)= 31.00 31.00 31.00 Tc TO OS1 FROM SWMM TRAVEL TIME (Tt)-L/(60*V) FLOW TYPE L (ft) = 160 S (!) - 2.00 SWALR V (fps) = 2.16 Tt(min)- 1.23 L (ft) = 100 S (t) = 0.50 GUTTER V (fps) = 1.50 Tt(min)= 1.11 L (ft) = 690 S (tr) = 1.00 GUTTER V (fps) = 2.00 Tt(min)- 5.75 L (ft) =? S (i) - 0.00 NONE V (fps) = 0.00 Tt(min)- 0.00 L (ft) =7 S (4) - 0.00 NONE V (fps) = 0.00 Tt(min)- 0.00 L (ft) =? S - 0.00 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) =? S (i) = 0.00 NONE V (fps) = 0.00 Tt(min)= 0.00 ALL VELOCITIES TAKEN FROM FIGURE 3-2 TOTAL TRAVEL TIME (min)- = 8.10 TOTAL LENGTH = 950 L/180+10= 15.28 < 39.10 Tc =Ti+TOTAL TRAVEL TIME 2 YEAR 10 YEAR 100 YEAR To (min)= 39.10 39.10 39.10 USE Ti FROM SWMM AND ADD Tt USE Tc = 39 39 39 INTENSITY (I) (iph) 2 YEAR 10 YEAR 100 YEAR I = 1.22 2.23 3.64 NOTE: INTENSITIES TAKEN FROM FIGURE 3-1 RUNOFF (Q- CIA) (cfs) 2 YEAR 10 YEAR 100 YEAR Qinlet = 2.98 5.43 11.10 DIRECT FLOW FROM A9 AND A10 Qtotal = 2.98 5.43 72.66 ADDED OVERFLOW. SEE PAGE Qint(N)= 7.00 7.00 7.00 SEE PAGE 11 Qint(S)= 7.00 7.00 7.00 SEE PAGE 12 Qover = 0.00 0.00 58.66 CONCLUDE:SENECA STREET IS OVERTOPPED DURING 100-YEAR STORM OVERFLOW GOES BOTH EAST ALONG AND NORTH OVER SENECA - 70/30 EAST/NORTH SEE PAGES 1 AND 2 OF 2 FOR OVERFLOW MODEL Qtotal - Qinlet+total overflow from Imperial Estates Qint = flow intercepted by inlet Qover = flows which bypass inlets and overtop Seneca 16 SHEAR ENGINEERING CORPORATION PAGE: 1 OF 2 STREET OVERFLOW AT INTERSECTION OF SENECA STREET AND PAINTED DESERT COURT PROTBCT WESTFIELD PARK P.U.D. DATE: 10/01/97 PROTECT NO 1005-44-94 BY MEO PILE : OVERFLOW PLOW LINE ELEVATION AT INLET ON PAINTED DESERT COURT _ 4.78 FT. CENTER LINE ELEVATION 0 9+72.56 ON SENECA - IN LINE WITH INLET 5.58 FT. PLOW LINE ELEVATION AT HP ON SENECA - STA 8+74.39 a 5.58 FT. CENTER LINE ELEVATION AT HP ON SENECA - STA 8+74.39 6.21 FT. CENTER LINE ELEVATION AT LP ON SENECA - STA 9+94.07 5.53 FT. PONDING WILL OCCUR UP TO LOW POINT ELEVATION 6 CENTERLINE a 5.53 FT. CONCLUDE: WATER WILL OVERFLOW TO THE EAST IN PAINTED DESERT COURT PRIOR TO OVERFLOWING TO THE NORTH ONTO SENECA STREET. THE DIFFERENCE BETWEEN THE CENTER LINE LOWPOINT AND THE FLOW LINE HIGHPOINT AT 8+71.39 IS 0.05 FEET SOME OF THE •OVERFLOW" WILL IN PACT BE INTERCEPTED BY THE INLETS WHILE IT IS PONDING¢ THIS IS IGNORED IN THIS CASE , SHEAR ENGINEERING CORPORATION PAGE 2 OF 2 MODEL OVERFLOW AT PAINTED DESERT COURT AND SENECA STREET PROTECT: WESTFIELD PARK DATE: 10/01/97 PROJECT NO 1004-44-94 BY MEO PILE: OVERFLOW UPPER WEIR INV. (ft) 5.53 HIGH POINT IN STREET 6.21 UPPER WHIR LENGTH(ft) 41.00 INIT. DELTA (ft) 0.22 UPPER WHIR COBF. (Cw) 2.60 DELTA HEAD (ft) 0.10 OVERFLOW AMOUNT 58.98 HIGH POINT ON SENECA 6.21 ' tte tt ttt ++++rr rrttrrrrrrrttrtt to tppTpUTtr++rrrxx tttt ttr+ ++tttrrrtxtrt+rr::tt tt tt HEAD ASSUMPTIONS: UPPER WEIR 1 WEIR LENGTH IS CENTERLINE LENGTH AT ELEVATION 5.58 BLEV. WEIR PLOW REFER TO STREET PROFILE AND EXHIBIT ft ft cfe 2 OVERFLOW IN BOTH DIRECTIONS BEGINS AT BLEV. 5.58 ______ ______ ___... 3 CENTERLINE OVERFLOW IS MODELED AS A BROADCRBSTED 5.53 0.00 0.00 WEIR 5.75 0.22 11.00 4 OVERFLOW TO NORTH IS MODELED AS STREET PLOW 5.85 0.32 19.30 BECAUSE THE STREET CONFIGURATION DOSS NOT ALLOW 5.95 0.42 29.02 FOR MODELING LIKE A WEIR 6.05 0.52 39.97 5 STREET IS ASSUMED TO BE ESSENTIALLY FLAT 6.15 0.62 52.04 6 WEIR ELEVATION IS LOW POINT AT CENTERLINE 6.21 0.68 59.78 5.58 0.05 1.19 POINT AT WHICH OVERFLOW TO NORTH BEGINS 6.12 6.59 48.31 ELEVATION AT WHICH COMBINED FLOWS =OVERFLOW AMOUNT ++r+trr •+rrrrt ttrtttt trot++ t+tt+tr trrrtrt ttt:tr+ BROADCRESTED.WBIR FLOW EQUATION CWLH�3/2 FLOWLINE ELEVATION AT HP 5.58 FT. LIP ELEVATION 0 HP - 5.75 FT. CENTERLINE ELEVATION ® HP 6.21 FT. Ym 6.21-5.58 = 0.63 FEET Y�(8/3) - 0.2917 Ymin = 5.75-5.58 0.17 FEET Y�(8/3) - 0.0089 CROSS SLOPE = 0.02 FT/FT Z - 1/CROSS SLOPE- 50.00 n = 0.016 Z/n - 3125.00 ASSUME S - 0.0010 FT/PT- ESSENTIALLY FLAT FROM Q - 0.56Z/nS�0.5yA(e/3) 0.56*(Z/n)*SA0.5 = 55.34 NORTH EAST ELEVATION Y Y"(8/3) Q Q Q STREET WEIR TOTAL ft £t efe cfe cfe 5.75 0.17 0.0089 0.49 11.00 11.49 5.85 0.27 0.0305 1.69 19.30 20.98 5.95 0.37 0.0706 3.90 29.02 32.92 6.05 0.47 0.1335 7.39 39.97 47.36 6.15 0.57 0.2234 12.36 52.04 64.40 6.21 0.63 0.2917 16.14 59.78 75.92 6.12 0.54 0.1934 10.70 48.31 59.01 *** CONCLUDE:EXCESS WATER OVERFLOWS SENECA STREET AT APPROXIMATELY ELEVATION = 6.12 PERT PERCENTAGE FLAWING NORTH 18.134 = 10.70 DIVIDED BY 59.01 PERCENTAGE FLAWING EAST 81.871r = 48.31 DIVIDED BY 59.01 USE 20:80 NORTH:RAST 0 O UUGi�r LOW Ex m a iT 86 1'Z 30cy— / 116 r 114 D \ r 109 U J vow r 0 117 • W 113 r 110 i r �W rao CIL� 0 N 'Z La 118 ~ 1; 112 r r 1 7+55.74 r. � C L INTERSECTION 10+25.31 ;.�j� 11 C/L STA. 8 71.20 9+48.84 "� P. +17.74� 8+ L P.C.R. 00 CTR SIDEWA P.C.R. 9+52. 6 � 00 '.C.R. CULVERTP.T.is r ; 7. 5.74 21 9+00 - 10+00 3 — P.C. 7+93.80 s`' 93. C3 Z� 9+90.26 `l�jt•z� s� S' - 10+ 1.38 3��fz. I?.. ' C L INTERSECTION P.C.R� _ _EXIST. 12"DIP W L . Z ID. ----- 7+70.48 EXIST. YN� 14 / 10+19.41 9+55.2 EX. 020.85' RT. r- — C.R. 20.10' RT. EL.=5105.17 +71.20 4,� g EL.=5105.62 7 1 EXIST. F.H. 59 I ( 10+16.49 77 Y 35.18' RT. 1 NI`� EX Wv 6 Q I EL.=5104.10 �� I17 34' RT. 4 MS'' EL.=5105.55 I 76 �I N 58I I I 61 I :;` Aj CD jv � 57 of I 75 .I �: I O" 62 I SHEAR BNGINSERING CORPORATION PAGE FLOW TO CONCENTRATION POINT 3 FROM SUB -BASIN A3all PROJECT: WESTFIELD PARK PUD DATE 10/07/97 LOCATION:FORT COLLINS PROJ. NO.1005-44-94 PILE: WBSTRUN BY MUD NOTE: BAST END OF PAINTED DESERT COURT AREA (A)= 0.920 ACRES RUNOFF COBF. (C) 2 YEAR 10 YEAR 100 YEAR C = 0.56 0.56 0.70 SEE SPREAD SHEET ATTACHED ON PAGE 3 TIME OF CONCENTRATION (Tc) OVERLAND TRAVEL TIME (Ti) LENGTH =na FEET SLOPE =na It 2 YEAR 10 YEAR 100 YEAR C = 0.20 0.20 0.25 Ti (min)= 31.00 31.00 31.00 Tc TO OS1 FROM SWMM TRAVEL TIME (Tt) -L/(60*V) FLOW TYPE L (ft) = 160 S (t) = 2.00 SWALE V (fps) = 2.16 Tt(min)= 1.23. L (ft) = 100 S (t) - 0.50 GUTTER V (fps) - 1.50 Tt(min)- 1.11 L (ft) - 690 S (t) - 1.00 GUTTER V (fps) - 2.00 Tt(min)- 5.75 L (ft) = 200 S (t) - 1.00 GUTTER V (fps) = 2.00 Tt(min)= 1.67 . L (ft) _? S (t) - 0.00 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) =7 S (t) - 0.00 NONE V (fps) = 0.00 Tt(min)- 0.00 L (ft) _? S (t) = 0.00 NONE V (fps) = 0.00 Tt(min)- 0.00 ALL VELOCITIES TAKEN FROM FIGURE 3-2 TOTAL TRAVEL TIME (min) = 9.76 TOTAL LENGTH = 1150 L/180+10= 16.39 < 40.76 Tc -Ti+TOTAL TRAVEL TIME 2 YEAR 10 YEAR 100 YEAR Tc (min). 40.76 40.76 40.76 USE Ti FROM SWMM AND ADD Tt. USE Tc = 41 41 41 INTENSITY (I) (iph) 14 2 YEAR 10 YEAR 100 YEAR I = 1.18 2.16 3.54 NOTE: INTENSITIES TAKEN FROM FIGURE 3-1 Qinlet 1.70 2.91 5.99 FLOW TO INLET FROM A3 WITH Tc - 5 RUNOFF (Q= CIA) (cfe) - FLOW BASED ON TC 41 2 YEAR 10 YEAR 100 YEAR Qdirect = 0.61 1.11 2.28 FLOW TO INLET FROM A3 WITH Tc - 41 Qover = 0.00 0.00 46.93 80% OF OVERFLOW FROM DP'S 9 & 10 Qtotal = 0.61 1.11 49.21 Qdirect + Qover Qint = 4.52 4.52 4.52 FLOW INTERCEPTED Qevale = 0.00 0.00 44.69 SIZE OVERFLOW SWALE FOR 1.33*Qover CONCLUDE:FIOW DEPTH (Yo) 0.50 ft 24•x38- BRCP CAPACITY/LF 1.13 cfe DESIGN SLOPE 0.50% REFER TO FIGURE 5-2 DESIGN CAPACITY 29.77 CPS INLET SIZE = 5 ft INCLUDES ABDUCTION FACTOR FOR INLETS INLET CAPACITY = 4.52 cfe Q10total- 1.11 OK INLET CAPACITY > 2.91 = Q10 INLET DIRECTLY FROM SUBBASIN A3 SHEAR ENGINEERING CORPORATION OVERFLOW CHANNEL PAGE 14a CHANNEL CAPACITY FOR SECTION G-G PROJECT NAME: WESTFIELD PARK PUD DATE: 10/01/97 PROJECT NO. : 1005-44-94 BY : HBO SWALE DESCRIPTION:SWALE CONVEYING OVERFLOW TO POND FROM DESIGN POINT 3 AT PAINTED DESERT COURT PILE: OVBRCHAN CAPACITY OF TRIANGULAR OR TRAPEZOIDAL CHANNEL CHANNEL CONFIGURATION: TRAPEZOIDAL CHANNEL LINING: GRASS OVERFLOW AMOUNT (cfe) = 44.69 SEE PAGE 14 DESIGN PLOW (cfe) = 59.44 1.33rQover Da Db Dc Sc n W I (ft) (ft) (£t) (t) (ft) (ft) 6.00 6.00 1.500 2.00 0.032 2.00 0.25 0.25 - LEFT BANK SLOPS- 4.00 :1 RUN:RISB 0.25 - RIGHT BANK SLOPE 4.00 :1 RUN:RISB DEPTH WIDTH AREA PBRIM R 2/3 Sc 1/2 Q V (e.f.) (ft) (e.f.) (ft) (A/P) (cfe) (ft/sec) ------------------------------------------------- ------- 1.50 14.00 12.00 14.37 0.89 0.14 69.89 5.82 1.25 12.00 8.75 12.31 0.80 0.14 45.77 5.23 1.00 10.00 6.00 10.25 0.70 0.14 27.58 4.60 0.75 8.00 3.75 8.18 0.59 0.14 14.64 3.90 0.50 6.00 2.00 6.12 0.47 0.14 6.233.11 1.40 13.20 10.64 23.54 0.85 0.14 59.49 5.59 r rrrrrr»»rr re rrr r:: rrrr rrrrrr rr rerr rr rrrrrr re rrrrer re re rrerrrrrr•rrrer DEPTH WIDTH AREA PBRIM R 2/3 Sc 1/2 Q V (e.f.) (ft) (e.f.) (ft) (A/P) (cfe) (ft/sec) CONCLUDB:PLOW DEPTH FOR DESIGN PLOW = 1.40 FEET FLOW DEPTH FOR DESIGN PLOW < DEPTH OF SWALE SWALE IS ADEQUATE OVERFLOW SWALE SUMMARY FOR WESTFIELD PARK PUD SECTION DESIGN SLOPE n DEPTH 8O'1TOM SIDE AREA HYD. Qcap Qdee FLOW POINT WIDTH SLOPE A RADIUS DEPTH ft ft H:1 R�2/3 cfe cfe ft 11111 t11f 11f11ttt 11ff 111 t tf 1tf t11tfffflltf tff lfftfffff if fff lffftfftllfff1ff1111f ttf1f111fftfff lffffff t1f111f S-E 2 2.00 0.032 0.75 1.00 4.00 3:00 0.5586 11.01 2.95 0.42 G-0 3 2.00 0.032 1.50 2.00 4.00 12.00 0.8868 69.89 59.44 1.40 F-P OS1 1.33% 0.024 2.50 8.00 4.00 17.45 0.9570 117.89 75.00 NA NOTE: Qdee . 1.33fQover DURING 100-YEAR EVENT 6 DESIGN POINT FLOW DEPTH . DEPTH OF FLOW FOR DESIGN FLOW DESIGN FLOW AT OS1 IS THE Q100 DETERMINED IN THE SWM MODEL. SHEAR ENGINEERING CORPORATION , PAGE 15 FLOW TO CONCENTRATION POINT 2 FROM SUB -BASIN A2 PROTECT: STOCKBRIDGE PUD DATE 10/07/97 LOCATION:FORT COLLINS PRO.T. NO.1005-44-94 FILE: WBSTRUN BY HBO NOTE: END OF PURPLE SAGE COURT - PROFILE C AREA (A)= 1.340 ACRES RUNOFF CORP. (C) 2 YEAR 10 YEAR 100 YEAR C 0.60 0.60 0.75 SHE SPREAD SHEET ATTACHED ON PAGE 3 TIME OF CONCENTRATION (TO OVERLAND TRAVEL TIME (Ti) LENGTH = 40 FEET SLOPE = 2.00 } 2 YEAR 10 YEAR 100 YEAR C = 0.20 0.20 0.25 Ti (min)- 8.47 8.41 8.00 TRAVEL TIME (It) =L/(60*V) FLOW TYPE L (ft) = 385 S (}) = 0.5 GUTTER V (fps) - 1.50 Tt(min)= 4.28 L (ft) =7 S (}) - 0 NONE V (fps) - 0.00 Tt(min)= 0.00 L (ft) =7 S (}) = 0 NONE V (fps) - 0.00 Tt(min)= 0.00 L (ft) =7 S (}) - 0 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) _? S (}) = 0 NONE V (fps) - 0.00 Tt(min)- 0.00 L (£t) _? S (}) = 0 NONE V (fps) - 0.00 Tt(min)= 0.00 L (ft) =? S (}) = 0 NONE V (fps) - 0.00 Tt(min)- 0.00 ALL VELOCITIES TAKEN FROM FIGURE 3-2 TOTAL TRAVEL TIME (min) = 4.28 TOTAL LENGTH = 425 L/180+10= 12.36 < 12.28 CHOOSE LESSER Tc =Ti+TOTAL TRAVEL TIME 2 YEAR 10 YEAR 100 YEAR Tc (min)= 12.36 12.36 12.28 USE Tc = 12 12 12 INTENSITY (I) (iph) 2 YEAR 10 YEAR 100 YEAR I = 2.38 4.17 6.71 NOTE: INTENSITIES TAKEN FROM FIGURE 3-1 RUNOFF (Q- CIA) (cfe) 2 YEAR 10 YEAR _ 100 YEAR Qinlet = 1.91 3.35 6.74 Qover 0.00 0.00 2.14 SIZE OVERFLOW SWALE FOR 1.33*Qover CONCLUDE:SIZE INLET FOR Q10 SIZE PIPE FOR Q100 PLOW DEPTH (Yo) 0.50 ft 15• ADS N-12 DESIGN SLOPS = 0.007 PT/PT CAPACITY/LP = 1.15 cfe DESIGN CAPACITY- 5.85 CPS INLET SIZE = 5 ft REFER TO FIGURE 5-2 INLET CAPACITY = 4.60•cfe - INCLUDES REDUCTION FACTOR FOR INLETS CAPACITY = 4.60 > Q10 - 3.35 OK PIPE CAPACITY BASED ON MANNINGS EQTN WITH PIPE FLOWING FULL SHEAR ENGINEERING CORPORATION OVERFLOW CHANNEL PAGE 15a CHANNEL CAPACITY FOR SECTION E-E PROJECT NAME: WESTFIELD PARK POD DATE: 10/07/97 PROJECT NO. : 1005-44-94 BY : HBO SWALE DBSCRIPTION:SWALE CONVEYING OVERFLOW TO POND PROM DESIGN POINT 2 AT PURPLE SAGE COURT FILE: OVBRCHAN CAPACITY OF TRIANGULAR OR TRAPEZOIDAL CHANNEL CHANNEL CONFIGURATION: TRAPEZOIDAL CHANNEL LINING: GRASS OVERFLOW AMOUNT (cfe) 2.14 SEE PAGE 15 DESIGN FLOW (cfe) = 2.85 1.33*Qover Da Db Dc Sc n W I (ft) (ft) (ft) (4) ---- ----- (ft) ---- (ft) ---- ---- 3.00 ---- 3.00 ---- 0.750 2.00 0.032 1.00 0.15 0.25 = LEFT BANK SLOPE 4.00 :1 RUN:RISB 0.25 = RIGHT BANK SLOPE 4.00 :1 RUN:RISB DEPTH WIDTH AREA PBRIM R 2/3 Sc 2/2 Q V (e.f.) (ft) (e.f.) (ft) ------- ------- (A/P) ------- (cfe) ------- (ft/sec) ------- ------- 0.75 ------- 7.00 ------- 3.00 7.28 0.56 0.14 11.02 3.67 0.60 5.80 2.04 5.95 0.49 0.24 6.56 3.22 0.45 4.60 2.26 4.71 0.42 0.24 3.43 2.73 0.30 3.40 0.66 3.47 0.33 0.14 1.43 2.17 0.25 2.20 0.24 2.24 0.23 0.24 0.36 1.48 0.42 4.36 1.13 4.46 0.40 0.14 2.95 2.62 •t�:•rte�+�+�e»�ttyrerrt•��r�t�ry:eyR���e�t�rw�e�e•�te���«e�f��f�+f rr• DEPTH WIDTH AREA PBRIM R 2/3 Sc 2/2 Q V (e.f.) (ft) (e.f.) (ft) (A/P) .(cfe) (ft/sec) CONCLUDE:FLOW DEPTH FOR DESIGN PLOW = 0.42 PERT FLOW DEPTH FOR DESIGN FLOW < DEPTH OF SWALE SWALE IS ADEQUATE SHEAR ENGINEERING CORPORATION PAGE 16 FLOW TO CONCENTRATION POINT OS-1 FROM SUB -BASIN OS-1 PROJECT: WESTFIELD PARK PUD DATE 05/30/97 LOCATION:FORT COLLINS PROJ. N0.1005-44-94 FILE: .WBSTRUN BY HBO EASTERN END OF IMPERIAL DRIVE FLOW TAKEN FROM SWMM MODEL RUNOFF (Q= CIA) (cfs) 2 YEAR 10 YEAR 100 YEAR Qsw = 11.1 NC 75.00 NC = NOT CALCULATED Qover = 0.00 0.00 61.56 Qaw - 13.44 CONCLUDB:INSTALL 2 AREA INLETS IN SUMP CONDITION WITH OVERFLOW CHANNEL SEE PAGE 6A SIZE GRATE TO HANDLE Qsw 2 WITH 1.00 FOOT FLOW DEPTH FROM FIG 5-3 CAPACITY PER SF OPEN AREA - 4.00 CFS/SF REDUCTION FACTOR 80.00tREQUIRED OPEN AREA FOR Qsw 2 = 3.47 SF USE NEENAH GRATE NO. 3339B WITH OPEN AREA = 2.10 SF X 2 = 4.2 SF CAPACITY OF BOTH Q 1.0 FOOT FLOW DEPTH = 13.44 > Qsw 2 OK FLOW INTERCEPTED AT EACH INLET - 6.72 CPS REQ'D SLOPE FOR IS- RCP = 0.0041 ft/ft SLOPE FROM AREA INLET TO AREA INLET 0.005 ft/ft SLOPE FROM AREA INLET TO MANHOLE = 0.0238 ft/ft SHEAR ENGINEERING CORPORATION OVERFLOW CHANNEL PAGE 16A CHANNEL CAPACITY FOR SECTION F-P PROJECT NAME: WESTFIELD PARK PUD DATE: 10/06/97 PROJECT NO. : 1005-44-94 BY : MEO SWALE DESCRIPTION:SWALE CONVEYING OVERFLOW TO PURPLE SAGE COURT FROM DESIGN POINT OS1 FILE: OVERCHAN CAPACITY OF TRIANGULAR OR.TRAPEZOIDAL CHANNEL CHANNEL CONFIGURATION: TRAPEZOIDAL CHANNEL LINING: GRASS AND CONCRETE OVERFLOW AMOUNT (cfe) 75.00 SHE PAGE 16 DESIGN FLOW (cfe) 75.00 Q100 FROM SWM MODEL DEPTH = 1.50 FEET SIDE SLOPES = 4 :1 H:V BOTTOM WIDTH - 9.00 FEET SLOPE (0) 0.0133 PT/FT Ngraee = 0.032 Nconcrete - 0.016 Pgraes = 9.64 Pconcrete - 9.00 SHE ATTACHED SKETCH FOR DESCRIPTION OF AREAS AND PERIMETERS Al = 0.64 Pl = 8.00 CONCRETE A = 0.5*8*0.16 P-(S�2+0.16^2)"0.5 A2 - 2.72 P2 = 0.50 CONCRETE A - 8*0.34 P=0.5 A3 = 8.50 P3 - 0.50 CONCRETE 9.00 A = 8.5*1 P=0.5 A4 = 3.59 P4 = 5.52 GRASS A = 0.5*1.34*5.36 P-(1.34^2+5.36"2)�0.5 AS - 2.00 PS = 4.12 GRASS 9.64 A - 0.5*1*4 17.45 18.64 P-(1.0^2+4.0^2)^0.5 R - A/P 0.9362 RA2/3 = 0.9570 N = 0.0243 CONVEYANCE FACTOR (C) _ (1.486*A*R^2/3)/N 1022.26 Qcapacity (Ce^0.5) = 117.09 cfe CONCLUDE SWALE IS ADEQUATE FLOW IS CONTAINED WITHIN LIMITS OF TRACT C I Lo co 0 M II 3 II O � z 40 W 3 W 0 0 Fo iM SHEAR ENGINEERING CORPORATION PAGE 17 FLOW TO CONCENTRATION POINT 11 FROM SUB -BASIN All PROJECT: WESTFIELD PARK PUD DATE 10/07/97 LOCATION:FORT COLLINS PROD. NO.1005-44-94 FILE: WESTRUN BY HBO INLET ON WEST SIDE OF BOX CULVERT ON HORSETOOTH AREA (A)= 0.140 ACRES RUNOFF CORP. (C) 2 YEAR 10 YEAR 100 YEAR C 0.84 0.84 1.00 SEE SPREAD SHEET ATTACHED ON PAGE 3 TIME OF CONCENTRATION (Tc) OVERLAND TRAVEL TIME (Ti) LENGTH -BA FEET SLOPS -MA • 2 YEAR 10 YEAR 100 YEAR C = 0.20 0.20 0.25 Ti (min) - TRAVEL TIME (Tt)-L/(60*V) FLOW TYPE L (ft) 100 S (i) - 0.50 GUTTER V (fps) - 1.50 Tt(min)- 1.11 L (ft) =7 S (t) = 0.00 NONE V (fps) - 0.00 Tt(min)- 0.00 L (ft) _? 8 (f) = 0.00 NONE V (fps) - 0.00 Tt(min)- 0.00 L (ft) _? S (t) = 0.00 NONE V (fps) = 0.00 Tt(min)- 0.00 L (ft) _? S (t) = 0.00 NONE V (fps) - 0.00 Tt(min)- 0.00 L (ft) =7 S (4) = 0.00 NONE V (fps) = 0.00 Tt(min)- 0.00 L (ft) _? S M = 0.00 NONE V (fps) - 0.00 Tt(min)= 0.00 ALL VELOCITIES TAKEN FROM FIGURE 3-2 TOTAL TRAVEL TIME (min) = 1.11 TOTAL LENGTH = 100 L/180+10- 10.56 < 1.11 _ Tc -Ti+TOTAL TRAVEL TIME 2 YEAR 10 YEAR 100 YEAR Tc (min). 1.11 1.11 1.11 USE Tc - 5 5 5 INTENSITY (I) (iph) 2 YEAR 10 YEAR 100 YEAR I 3.29 5.64 9.30 NOTE: INTENSITIESTAKEN FROM FIGURE 3-1 RUNOFF (q= CIA) (cfe) 13.12 FLOW INTERCEPTED BY INLET AT IMPERIAL DRIVE 2 YEAR 10 YEAR 100 YEAR Qdirect = 0.39 0.66 1.30 direct flow from All Qover 0.00 0.00 0.00 CONCLUDE:SIZE INLET FOR 100-YEAR STORM FLOW DEPTH (Yo) = 0.76 ft PIPE SIZE = 1.25 FEET CAPACITY/LP = 1.75 cfe PIPE TYPE - ADS N-12 REFER TO FIGURE 5-2 DESIGN SLOPE 1.00to INLET SIZE 5 ft DESIGN CAPACITY 7.00 CPS INLET CAPACITY 7.00 cfe INCLUDES REDUCTION FACTOR FOR INLETS CAPACITY = 7.00 > 0100 1.30 OK PIPE CAPACITY BASED ON MANNINGS EQTN WITH PIPE PLOWING FULL PLOW SUMMARY FOR WESTFIELD PARK PUD PAGE 18 DESIGN CONTRIBUTING AREA C2 C10 C100 Tc Tc I2 I10 I100 Q2 Q10 Q100 DESIGN POINT SUB 2,10 100 Q PAGE BASINS) ac. min. min iph iph iph cfe cfe cfe cfe set tttrtrrtrtrrrr rtr:r:ttt+rt++t+r+•trrtrrrrtr+t++trirrrrtt tr++tr+rt+trr+rirrrrrrrtrrtrr+rrrrrirt rrtrttrtt: DESIGN PLOWS FOR DRAINAGE SWALES Sa ASa & OSSa 1.60 0.41 0.41 0.51 14.50 14.50 2.18 3.82 6.17 1.43 2.51 5.06 6.73 19 Sb ASb & OSSb 1.60 0.39 0.39 0.49 14.00 14.00 2.22 3.89 6.28 1.39 2.43 4.90 6.51 20 Sc ASc 0.98 0.43 0.43 0.54 5.00 5.00 3.29 5.64 9.30 1.39 2.38 4.90 6.52 21 7a A7a SHE SWM MODEL FOR PEAK PLOWS TO CULVERT NA NC 178.90 178.90 22 10a AlOa & 0SIO 1.44 0.43 0.43 0.54 13.00 13.00 2.30 4.03 6.49 1.42 2.50 5.02 6.68 23 B1 Ble 1.00 0.5 0.5 0.625 13.5 13.5 2.26 3.96 6.384 1.13 1.98 3.99 5.31 24 B2 B2 0.95 0.46 0.46. 0.58 12.00 11.50 2.38 4.17 6.82 1.04 1.82 3.72 4.95 25 NOTES: *+ CHANNEL ALONG HORSETOOTH IS DESIGNED TO CONVEY THESE PLOWS. FIFTEEN (15') DRAINAGE BASEMENT PROVIDED AT REAR OF LOTS 1-9 REFER TO TRACT A CHANNEL SECTION ON PAGE 24B ++.Q100 BASED ON SWMM PLOWS FROM IMPERIAL ESTATES r NC NOT CALCULATED BY SWMM NA = NOT APPLICABLE SWALE SUMMARY FOR WESTFIELD PARK PUD PAGE 18a SECTION DESIGN SLOPE n DEPTH BOTTOM SIDE AREA HYD. Qcap Qdea FLOW PAGE POINT WIDTH SLOPE A RADIUS DEPTH t ft ft H:1 of R-2/3 cfe cfa ft Ter++rr rr rrre rre++r++r»r»»er++e•++rr»r»e»ere++++r rr rrree rvrre r+++++r»re+e+rrrrre++e +r+rr r:rr++++r++++r++++r A -A Sc. 0.50 0.027 0.60 2.00 10.00 4.80 0.4885 9.12 6.52 0.52 21a B-B So 0.80 0.028 0.60 2.00 10.00 4.80 0.4885 11.13 6.73 0.48 19a C-C Sb 0.50 0.028 0.60 2.00 10.00 4.80 0.4885 8.80 6.51 0.53 20a D-D 10a 0.50 0.028 0.60 2.00 10.00 4.80 0.4885 8.80 6.68 0.53 23a J-J B1 1.00 0.032 1.00 0.00 4.00 4.00 0.6173 11.47 5.31 0.75 24a K-K B2 1.67 0.032 0.75 - 0.00 4.00 2.25 0.5096 6.88 4.95 0.66 25a NOTE: Qdea - 1.33+Q100 ® DESIGN POINT FLOW DEPTH = DEPTH OF FLOW FOR DESIGN FLOW 0 6 OVERFLOW SWALE SUMMARY FOR WESTFIELD PARK PUD SECTION DESIGN SLOPS n DEPTH BOTTOM SIDE AREA HYD. Qcap Qdes PLOW POINT WIDTH SLOPE A RADIUS DEPTH % ft ft H:1 R'2/3 cfe cfa ft ++r++rr••r+•rrr+rrrr+rrr+:rrrrrr++rr+r:r++:rrr+r+rrrrrrrr rrr:r:r: rrr rr+r+++++++r++rrrrrrrrre: r:rrrrrrrr:rrrr E-E 2 2.00 0.032 0.75 1.00 4.00 3.00 0.5586 11.01 2.95 0.42 G-G 3 2.00 0.029 1.00 2.00 4.00 6.00 0.6999 30.43 15.56 0.74 F-F OS1 1.331* 0.024 1.50 8.00 4.00 20.04 1.0601 150.71 75.00 NA NOTE: Qdes = 1.33rQover DURING 100-YEAR EVENT M DESIGN POINT PLOW DEPTH = DEPTH OF PLOW FOR DESIGN PLOW DESIGN FLOW AT OS1 IS THE Q100 DETERMINED IN THE SWM MODEL. SHEAR ENGINEERING CORPORATION PAGE 19 FLOW TO CONCENTRATION POINT Sa FROM SUB -BASIN ASa S OSSa PROJECT: WESTFIELD PARK PUD DATE O6/11/97 LOCATION:FORT COLLINS PROD. NO.1005-44-94 FILE: SWALBRUN BY HBO AREA (A)= 1.600 ACRES RUNOFF CORP. (C) 2 YEAR 10 YEAR 100 YEAR C = 0.41 0.41 0.51 SEE SPREAD SHEET ATTACHED ON PAGE 3 TIME OF CONCENTRATION (TO OVERLAND TRAVEL TIME (Ti) LENGTH = 140 FEET SLOPE = 1.00 t 2 YEAR 10 YEAR 100 YEAR C 0.20 0.20 0.25 Ti (min). 19.91 19.91 18.81 TRAVEL TIME (TO=L/(60*V) FLOW TYPE L (ft) = 680 S (t) = 1.00 SWALE V (fps) - 1.58 Tt(min)= 7.17 L (ft) _? S (t) = 0 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) _? S (t) = 0 NONE V (fps) = 0.00 Tt(min)= 0.00 L (£t) _? S (t) = 0 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) _? S (t) = 0 NONE V (fps) - 0.00 Tt(min)= 0.00 L (ft) _? S (t) = 0 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) _? S (t) = 0 NONE. V (fps) = 0.00 Tt(min)= 0.00 ALL VELOCITIES TAKEN FROM FIGURE 3-2 TOTAL TRAVEL TIME (min) = 7.17 TOTAL LENGTH = 820 L/180+10- 14.56 < 25.98 CHOOSE LESSER Tc =Ti+TOTAL TRAVEL TIME 2 YEAR 10 YEAR 100 YEAR Tc (min)= 14.56 14.56 14.56 USE Tc = 14.5 14.5 14.5 INTENSITY (I) (iph) 2 YEAR 10 YEAR 100 YEAR I = 2.18 3.82 6.17 NOTE: INTENSITIES TAKEN FROM FIGURE 3-1. RUNOFF (Q= CIA) (cfs) 2 YEAR 10 YEAR 100 YEAR Q = 1.43 2.51 5.06 CONCLUDE:SWALE WITH VALLEY PAN IF SLOPE IS LESS THAN 2% DESIGN FLOW = 1.33*0100 = 6.73 CPS SEE PAGE 19 A REFER TO SECTION B-B INSTALL AREA INLET AND PIPE TO INLET ON SENECA I SHEAR ENGINEERING CORPORATION PAGE 19a CHANNEL CAPACITY FOR SECTION B-B PROJECT NAME: WESTFIELD PARK PUD DATE: 07/31/97 PROJECT NO. 1005-44-94 BY : MHO SWALE DESCRIPTION:SWALE CONVEYING PLOW TO DESIGN POINT Sa PILE: WESTCHAN CAPACITY OF TRIANGULAR OR TRAPEZOIDAL CHANNEL CHANNEL CONFIGURATION: TRAPEZOIDAL WITH VALLEY PAN CHANNEL LINING: GRASS Q100 (cfe) 5.06 - DESIGN FLOW (cfe)- 6.73 Da Db Dc Sc n W I (ft) (ft) (ft) (% . (ft) (ft) 6.00 6.00 0.600 0.80 0.028 2.00 0.15 0.10 - LEFT BANK SLOPE 10.00 :1 SIDE SLOPE (H:V) 0.10 = RIGHT BANK SLOPS 10.00 :1 SIDE SLOPE (H:V) - DEPTH WIDTH AREA PERIM R 2/3 Sc 1/2 Q V (ft) (ft) (6.f.) (ft) (A/P) (cfe) (ft/sec) ------ ------- ------- ------- ------- ------- ------- ------- 0.60 14.00 4.80 14.06 0.49 0.09 11.13 2.32 0.45 11.00 2.93 11.04 0.41 0.09 5.73 1.96 0.30 8.00 1.50 8.03 0.33 0.09 2.33 1.55 0.15 5.00 0.53 5.01 0.22 0.09 0.55 1.05 0.00 2.00 0.00 2.00 0.00 0.09 0.00 0.00 0.483 11.66 3.30 11.71 0.43 0.09 6.73 2.04 tt rr+r rrarr+rant+++vr•vrv+rarrtrvtertt+tt+v++rttrttrttrttrttttttttrtttt DEPTH WIDTH AREA PERIM R 2/3 Sc 1/2 Q V (e.f.) (ft) (e.f.) (ft) (A/P) (cfe) (ft/eec) COMPOSITE N VALUE CALCULATION n GRASS WIDTH (ft) = 12.00 0.032 CONCRETE WIDTH (ft) = 2.00 0.016 COMPOSITE N - 0.0297 USE n 0.028 CONCLUDS:FLOW DEPTH FOR DESIGN FLOW = 0.48 FEET FLOW DEPTH FOR DESIGN FLOW < DEPTH OF SWALE SWALE IS ADEQUATE SHEAR ENGINEERING CORPORATION PAGE 20 PLOW TO CONCENTRATION POINT Sb FROM SUB -BASIN A5b 6 OSSb PROJECT: WESTFIELD PARK POD DATE 05/30/97 LOCATION:FORT COLLINS PROD. NO.1005-44-94 PILE: SWALBRUN BY MBO AREA (A)- 1.600 ACRES RUNOFF CORP. (C) 2 YEAR 10 YEAR 100 YEAR C = 0.39 0.39 0.49 SEE SPREAD SHEET ATTACHED ON PAGE 3 , TIME OF CONCENTRATION (TO OVERLAND TRAVEL TIME (Ti) LENGTH = 140 FEET SLOPE = 1.00 4 2 YEAR 10 YEAR 100 YEAR C = 0.20 0.20 0.25 Ti (min)= 19.91 19.91 18.81 TRAVEL TIME (Tt)-L/(60*V) PLOW TYPE L (ft) = 600 S (i) - 1.00 SWALE V (fps) - 1.58 Tt(min)= 6.33 L (ft) _? S (i) - 0 NONE V (fps) = 0.00 Tt(min)- 0.00 L (ft) _? S (t) = 0 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) _? S (i) = 0 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) _? S (4) = 0 NONE V (fps) = 0.00 Tt(min)- 0.00 L (ft) _? S = 0 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) _? S = 0 NONE V (fps) = 0.00 Tt(min)= 0.00 ALL VELOCITIES TAKEN FROM FIGURE 3-2 TOTAL TRAVEL TIME (min) 6.33 TOTAL LENGTH - 740 L/180+10= 14.11 < 25.14 CHOOSE LESSER Tc =Ti+TOTAL TRAVEL TIME 2 YEAR 10 YEAR 100 YEAR Tc (min)= 14.11 14.11 14.11 USE Tc = 14 14 14 INTENSITY (I) (iph) , 2 YEAR 10 YEAR 100 YEAR I = 2.22 3.89 6.28 NOTE: INTENSITIES TAKEN FROM FIGURE 3-1 RUNOFF (Q- CIA) (cfs) 2 YEAR 10 YEAR 100 YEAR Q = 1.39 2.43 4.90 CONCLUDE:SWALE WITH VALLEY PAN IF SLOPE IS LESS THAN 2t DESIGN PLOW = 1.33*Q100 = 6.51 CPS SHE PAGE 20 A REFER TO SECTION C-C L SHEAR ENGINEERING CORPORATION I PAGE 20a CHANNEL CAPACITY FOR SECTION C-C PROJECT NAME: WESTFIELD PARK PUD DATE: 07/31/97 PROJECT NO. 1005-44-94 BY : MEO SWALE DESCRIPTION:SWALE CONVEYING FLOW TO DESIGN POINT 5b PILE: WESTCHAN CAPACITY OF TRIANGULAR OR TRAPEZOIDAL CHANNEL CHANNEL CONFIGURATION: TRAPEZOIDAL WITH VALLEY PAN CHANNEL LINING: GRASS Q100 (cfe) = 4.89 DESIGN FLOW (cfe)= 6.51 Da Db Dc Sc n W I (ft) (ft) (ft) (4) (ft) (ft) ____ ____ ____ ____ _____ ____ ____ 6.00 6.00 0.600 0-.50 0.028 2.00 0.15 0.10 = LEFT BANK SLOPE 10.00 :1 SIDE SLOPE (H:V) 0.10 = RIGHT BANK SLOPE 10.00 :1 SIDH SLOPE (H:V) DEPTH WIDTH AREA PERIM R 2/3 Sc 1/2 Q V (ft) (ft) (e.£.) (ft) (A/P) (cfe) (ft/eec) ------- ---"'- ------- ------- ------- ------- ------- ------- 0.60 14.00 4.80 14.06 0.49 0.07 8.80 1.83 0.45 11.00 2.93 11.04 0.41 0.07 4.53 1.55 0.30 8.00 1.50 8.03 0.33 0.07 1.84 1.23 0.15 5.00 0.53 5.01 0.22 0.07 0.44 0.83 0.00 2.00 0.00 2.00 0.00 0.07 0.00 0.00 0.528 12.56 3.84 12.61 0.45 0.07 6.53 1.70 f11f)f##f##ff Yf t11t t1 t1ttttflttt llttf tf tff iflff##f##ff##f #f#Yf Yf Yf tf Yfll ' DEPTH WIDTH AREA PERIM R 2/3 Sc 1/2 Q V (a.f.) (ft) (e.f.) (ft) (A/P) (cfe) (ft/sec) ' COMPOSITE N VALUE CALCULATION n GRASS WIDTH (ft) 12.00 0.032 CONCRETE WIDTH (ft) = 2.00 0.016 COMPOSITE N = 0.0297 USE n = 0.028 CONCLUDE:FLOW DEPTH FOR DESIGN FLOW = 0.53 FEET FLOW DEPTH FOR DESIGN FLOW < DEPTH OF SWALE SWALE IS ADEQUATE SHEAR ENGINEERING CORPORATION PAGE 21 FLAW TO CONCENTRATION POINT 5c FROM SUB -BASIN ASc PROJECT: WESTFIELD PARK PUD DATE 05/30/97 LACATION:FORT COLLINS PROJ. NO.1005-44-94 FILE: SWALERUN BY MEO AREA (A)= 0.980 ACRES RUNOFF CORP. (C) 2 YEAR 10 YEAR 100 YEAR C = 0.43 0.43 0.54 SEE SPREAD SHEET ATTACHED ON PAGE 3 TIME OF CONCENTRATION (Tc) OVERLAND TRAVEL TIME (TO NOT APPLICABLE LENGTH =? FEET SLOPE _? 3 2 YEAR 10 YEAR 100 YEAR C = 0.20 0.20 0.25 Ti (min)= 0.00 0.00 0.00 TRAVEL TIME (Tt)=L/(60*V) PLOW TYPE L (ft) = 470 S M - 1.00 SWALB V (fps) = 1.58 Tt(min)= 4.96 L (ft) _? S (i) - 0 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) _? S (i) - 0 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) _? S (1) = 0 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) _? S 00 - 0 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) _? S (k) - 0 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) _? S (14) - 0 NONE V (fps) = 0.00 Tt(min)= 0.00 ALL VELOCITIES TAKEN FROM FIGURE 3-2 TOTAL TRAVEL TIME (min) = 4.96 TOTAL LENGTH = 470 L/180+10- 12.61 > 4.96 CHOOSE LESSER Tc =Ti+TOTAL TRAVEL TIME 2 YEAR 10 YEAR 100 YEAR Tc (min)= 4.96 4.96 4.96 USE Tc = 5 5 5 INTENSITY (I) (iph) 2 YEAR 10 YEAR 100 YEAR I = 3.29 5.64 9.30 NOTE: INTENSITIES TAKEN FROM FIGURE 3-1 RUNOFF (Q= CIA) (cfs) 2 YEAR 10 YEAR 100 YEAR Q = 1.39 2.38 4.90 CONCLUDE:SWALE WITH VALLEY PAN IF SLOPE IS LESS THAN 2% DESIGN FLOW = 1.33•Q100 - 6.52 CPS SHE PAGE 21 A REFER TO SECTION A -A SHEAR ENGINEERING CORPORATION PAGE 21a CHANNEL CAPACITY FOR SECTION A -A PROTECT NAME: WESTFIELD PARK PUD DATE: 07/31/97 PROTECT NO. 1005-44-94 BY : MEO SWALE DESCRIPTION:SWALE CONVEYING FLOW TO DESIGN POINT Sc FILE: WBSTCHAN CAPACITY OF TRIANGULAR OR TRAPEZOIDAL CHANNEL CHANNEL CONFIGURATION: TRAPEZOIDAL WITH VALLEY PAN CHANNEL LINING: GRASS 0100 (cfe) 4.90 DESIGN FLOW (cfe)= 6.52 Da Db Dc Sc n W I (ft) (ft) (ft) (4) (ft) (ft) 6.00 6.00 0.600 0.50 0.027 2.00 0.15 q: 0.10 - LEFT BANK SLOPE 10.00 :1 SIDE SLOPE (H:V) 0.10 = RIGHT BANK SLOPE 10.00 :1 SIDE SLOPE (H:V) DEPTH WIDTH AREA PBRIM R 2/3 Sc 1/2 Q V (ft) (ft) (e.£.) (ft) (A/P) (cfe) (ft/sec) ------- ------- ------- ------- ------- --------------------- 0.60 14.00 4.80 14.06 0.49 0.07 9.12 1.90 0.45 11.00 2.93 11.04 0.41 0.07 4.69 1.60 0.30 8.00 1.50 8.03 0.33 0.07 1.91 1.27 _ 0.15 5.00 0.53 5.01 0.22 0.07 0.45 ' 0.86 0.00 2.00 0.00 2.00 0.00 0.07 0.00 0.00 0.520 12.40 3.74 12.45 0.45 0.07 6.54 1.75 r rrrr+rrrrrrrtrrrrtrrrrr+r+t:r+rr+rrrrrrtrrrrttrrrrrt+rrrrtrr+rr++:r++++ ' DEPTH WIDTH AREA PERIM R 2/3 Sc 1/2 Q V (s.f.) (ft) (s.f.) (ft) (A/P) (cfe) (ft/eec) COMPOSITE N VALUE CALCULATION n GRASS WIDTH (ft) = 12.00 0.032 CONCRETE WIDTH (ft) = 2.00 0.016 COMPOSITE N = 0.0297 USE n = 0.028 CONCLUDE:PLOW DEPTH FOR DESIGN FLOW = 0.52 FEET FLAW DEPTH FOR DESIGN FLOW < DEPTH OF SWALE SWALE IS ADEQUATE SHEAR ENGINEERING CORPORATION PAGE 22 PLOW TO CONCENTRATION POINT 7a FROM SUB -BASIN A7a PROJECT: WESTFIELD PARK PUD DATE 05/30/97 LOCATION:FORT COLLINS PROJ: NO.1005-44-94 FILE: SWALBRUN BY MHO AREA (A)= 2.770 ACRES RUNOFF COEF. (C) 2 YEAR 10 YEAR 100 YEAR C = 0.36 0.36 0.45 SHE SPREAD SHEET ATTACHED ON PAGE 3 e TIME OF CONCENTRATION (Tc) OVERLAND TRAVEL TIME (Ti) LENGTH =? FEET SLOPE _? 4 2 YEAR 10 YEAR 100 YEAR C = 0.20 0.20 0.25 Ti (min)= 39.00 39.00 39.00 FROM SWMM MODEL TRAVEL TIME (Tt)=L/(60*V) FLOW TYPE L (ft) = 500 S (i) = 0.50 GUTTER V (fps) = 1.50 Tt(min)- 5.56 L (ft) = 250 S (i:) _ 0.50 SWALH V (fps) - 1.11 Tt(min)= 3.75 L (ft) _? S (4) - 0 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) _? S (%) - 0 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) _? S (1k) = 0 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) _? S (i) = 0 NONE V (fps) = 0.00 Tt(min)- 0.00 L (ft) _? S (ok) = 0 NONE V (fps) - 0.00 Tt(min)= 0.00 ALL VELOCITIES TAKEN FROM FIGURE 3-2 TOTAL TRAVEL TIME (min) 9.31 TOTAL LENGTH = 750 L/180+10= 14.17 < 48.31 CHOOSE LESSER Tc =Ti+TOTAL TRAVEL TIME 2 YEAR 10 YEAR 100 YEAR Tc (min)- 48.31 48.31 48.31 USE Tc = 48.5 48.5 48.5 INTENSITY (I) (iph) 2 YEAR 10 YEAR I = 1.06 1.92 NOTE: INTENSITIES TAKEN FROM FIGURE RUNOFF (Q= CIA) (cfs) 2 YEAR 10 YEAR Q = 1.06 1.91 Qewmm 20.40 NC 100 YEAR 3.10 3-1 100 YEAR 3.86 178.90 NC = NOT CALC'D BY SWMM CONCLUDE:USE QSWMM IN DESIGN OF CHANNEL AND BOX CULVERT ASSUMES ALL THE FLOWS FROM IMPERIAL ESTATES ARE DIVERTED INTO THE CHANNEL AT THE WESTERN END OF THE CURB AND GUTTER ALONG HORSHTOOTH SHEAR ENGINEERING CORPORATION PAGE 23 FLOW TO CONCENTRATION POINT 10a FROM SUB -BASIN AlOa & OS10a PROJECT: WESTFIELD PARK PUD DATE 05/30/97 LOCATION:FORT COLLINS PROD. NO.1005-44-94 PILE: SWALERUN BY MHO AREA (A)= 1.440 ACRES RUNOFF CORP. (C) 2 YEAR 10 YEAR 100 YEAR C = 0.43 0.43 0.54 SEE SPREAD SHEET ATTACHED ON PAGE 3 TIME OF CONCENTRATION (Tc) OVERLAND TRAVEL TIME (Ti) LENGTH = 80 PERT SLOPE = 1.00 t 2 YEAR 10 YEAR 100 YEAR C 0.20 0.20 0.25 Ti (min)= 15.05 15.05 - 14.22 TRAVEL TIME (TO=L/(60*V) PLOW TYPE L (ft) = 495 S (t) - 1.00 SWALE V (fps) = 1.58 Tt(min)- 5.22 L (ft) _? S M. = 0 NONE V (fps) 0.00 Tt(min)- 0.00 L (ft) _? S (t) = 0 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) _? S (t) = 0 NONE V (fps) = 0.00 Tt(min)- 0.00 L (ft) _? S (t) - 0 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) _? S (t) = 0 NONE V (fps) _ 0.00 Tt(min)- 0.00 L (ft) _? S (t) = 0 NONE V (fps) = 0.00 Tt(min)- 0.00 ALL VELOCITIES TAKEN FROM FIGURE 3-2 TOTAL TRAVEL TIME (min) = 5.22 TOTAL LENGTH - 575 L/180+10- 13.19 < 19.44 CHOOSE LESSER Tc -Ti+TOTAL TRAVEL TIME 2 YEAR 10 YEAR 100 YEAR Tc (min)= 13.19 13.19 23.19 USE Tc = 13 13 13 VERIFY INTENSITY (I) (iph) 2 YEAR 10 YEAR 100 YEAR I = 2.30 4.03 6.49 NOTE: INTENSITIES TAKEN FROM FIGURE 3-1 RUNOFF (Q= CIA) (cfs) 2 YEAR 10 YEAR 100 YEAR Q = 1.42 2.50 5.02 CONCLUDS:SWALE WITH VALLEY PAN IF SLOPE IS LESS THAN 2% DESIGN FLOW = 1.33*Q100 = 6.68 SEE PAGE 23 A 3 I SHEAR ENGINEERING CORPORATION PAGE 23a CHANNEL CAPACITY FOR SECTION D-D PROJECT NAME: WESTFIELD PARK PUD DATE: 07/31/97 PROJECT NO. 1005-44-94 BY : MEO SWALE DESCRIPTION:SWALE CONVEYING FLOW TO DESIGN POINT 10a FILE: WESTCHAN CAPACITY OF TRIANGULAR OR TRAPEZOIDAL CHANNEL CHANNEL CONFIGURATION: TRAPEZOIDAL WITH VALLEY PAN CHANNEL LINING: GRASS Q100 (c£s) - 5.02 DESIGN FLOW (cfe)= 6.68 Da Db Dc Sc n W I (ft) (ft) (ft) (t) (ft) ----- ---- (ft) ---- ---- 6.00 ---- ---- ---- 6.00 0.600 0.50 0.028 2.00 0.11 0.10 = LEFT BANK SLOPE 10.00 :1 SIDE SLOPE (H:V) 0.10 = RIGHT BANK SLOPE 10.00 :1 SIDS SLOPE (H:V) DEPTH WIDTH AREA PBRIM R 2/3 Sc 1/2 Q V (ft) (ft) .(s.f.) (ft) (A/P) (cfs) (ft/sec). --------------------- -------------- --------------------- 0.60 14.00 4.80 14.06 0.49 0.07 8.80 1.83 0.45 11.00 2.93 11.04 0.41 0.07 4.53 1.55 0.30 8.00 1.50 8.03 0.33 0.07 1.84 1.23 0.15 5.00 0.53 5.01 0.22 0.07 0.44 0.83 0.00 2.00 0.00 2.00 0.00 0.07 0.00 0.00 0.533 12.66 3.91 12.71 0.46 0.07 6.68 1.71 +r++•rrrr+++++++r++:+:+++•r+r♦rr+++r++++++rr:r+r+++rr++r+r+rr+rr++:r++++ DEPTH WIDTH AREA PERIM R 2/3 Sc 1/2 Q V (s.f.) (ft) (s.f.) (ft) (A/P) (cfe) (ft/sec) COMPOSITE N VALUE CALCULATION n GRASS WIDTH (ft) = 12.00 0.032 CONCRETE WIDTH (ft) 2.00 0.016 COMPOSITE N = 0.0297 USE n = 0.028 CONCLUDE:FLOW DEPTH FOR DESIGN FLOW - 0.53 FEET FLOW DEPTH FOR DESIGN FLOW < DEPTH OF SWALE SWALE IS ADEQUATE SHEAR ENGINBBRING CORPORATION PAGE 24 PLOW TO CONCENTRATION POINT B1 FROM SUB -BASIN BIG PROJECT: WESTFIELD PARK PUD DATE 06/11/97 LOCATION:FORT COLLINS PROJ. NO.1005-44-94 FILE: SWALBRUN BY MEO AREA (A)= 1.000 ACRES RUNOFF COEP. (C) 2 YEAR 10 YEAR 100 YEAR C = 0.50 0.50 0.63 SEE SPREAD SHEET ATTACHED ON PAGE 3 TIME OF CONCENTRATION (TO OVERLAND TRAVEL TIME (Ti) LENGTH 40 FEET SLOPE = 2.00 t 2 YEAR 10 YEAR 100 YEAR C = 0.20 0.20 0.25 Ti (min)- 8.47 - 8.47 8.00 TRAVEL TIME (Tt)=L/(60*V) PLOW TYPE e' L (ft) = 600 S (t) - 1.00 SWALE V (fps) 1.58 Tt(min)= 6.33 L (ft) _? S (t) = 0 NONE V (fp0) = 0.00 Tt(min)- 0.00 L (ft) _? S (t) = 0 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) _? S (t) = 0 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) =7 S (t) _, 0 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) =7 S (t) = 0 NONE V (fps) = 0.00 Tt(min)= 0.00 L (ft) _? S (4) = 0 NONE V (fps) = 0.00 Tt(min)- 0.00 ALL VELOCITIES TAKEN FROM FIGURE 3-2 TOTAL TRAVEL TIME (min) 6.33 TOTAL LENGTH = - -640 L/180+10- 13.56 < 14.33 CHOOSE LESSER Tc -Ti+TOTAL TRAVEL TIME 2 YEAR 10 YEAR 100 YEAR Tc (min)= 13.56 13.56 13.56 USE Tc = 13.5 13.5 13.5 INTENSITY (I) (iph) 2 YEAR 10 YEAR 100 YEAR I = 2.26 3.96 6.38 NOTE: INTENSITIES TAKEN FROM FIGURE 3-1 RUNOFF (Q= CIA) (cfa) 2 YEAR _ 10 YEAR 100 YEAR . Q = 1.13 1.98 3.99 CONCLUDE:SWALB WITH VALLEY PAN IP SLOPE IS LESS THAN 21k DESIGN FLOW = 1.33*QI00 - 5.31 CPS ' SEE PAGE 24 A REFER TO SECTION J-J SHEAR ENGINEERING CORPORATION PAGE 24a CHANNEL CAPACITY FOR SECTION J-J PROJECT NAME: WESTFIELD PARK PUD DATE: 07/31/97 PROJECT NO. : 1005-44-94 BY : HBO SWALE DESCRIPTION:SWALE CONVEYING FLOW TO DESIGN POINT B1 FILE: WESTCHAN CAPACITY OF TRIANGULAR OR TRAPEZOIDAL CHANNEL CHANNEL CONFIGURATION: GRASSED TRIANGULAR CHANNEL LINING: GRASS 0100 (cfa) = 3.99 DESIGN FLOW (cfa)= 5.31 Da Db Dc Sc n W I (ft) (ft) (ft) 00 ---- ----- (ft) ---- (ft) ---- ---- 4.00 ---- ---- 4.00 1.00 1.00 0.032 0.00 0.25 0.25 = LEFT BANK SLOPE 4.00 :1 SIDE SLOPE (H:V) 0.25 = RIGHT BANK SLOPE 4.00 :1 SIDE SLOPS (H:V) DEPTH WIDTH AREA PERIM R 2/3 Sc 1/2 Q V (ft) (ft) (s.f.) (ft) (A/P) (cfe) (ft/sec) -------------------------------------------------------- 1.00 8.00 4.00 8.25 0.62 0.10 11.47 2.87 0.75 6.00 2.25 6.18 0.51 0.10 5.32 2.37 0.50 4.00 1.00 4.12 0.39 0.10 1.61 1.81 0.25 2.00 0.25 2.06 0.24 0.10 0.28 1.14 0.749 5.99 2.24 6.18 0.51 0.10 5.31 2.36 t ttrtrrrrrr rrrrrrrtetrr•rrrrr rrrr:r:rrrr+rr+++ttrttttrrrrrrrr:r♦ttt rr+++ DEPTH WIDTH AREA PERIM R 2/3 Sc 1/2 Q V (s.f.) (ft) (s.f.) (ft) (A/P) (cfe) (ft/sec) COMPOSITE N VALUE CALCULATION n GRASS WIDTH (ft) = 8.00 0.032 CONCRETE WIDTH (ft) = 0.00 0.016 COMPOSITE N = 0.0320 USE n = 0.028 CONCLUDE:FLOW DEPTH FOR DESIGN FLOW = 0.75 FEET FLOW DEPTH FOR DESIGN FLOW < DEPTH OF SWALE SWALE IS ADEQUATE SHEAR ENGINEERING CORPORATION PAGE 25 FLOW TO CONCENTRATION POINT B2 FROM SUB -BASIN B2 PROTECT: WESTFIELD PARK PUD DATE 07/31/97 LOCATION:PORT COLLINS PROJ. NO.1005-44-94 FILE: SWALRRUN BY MHO AREA (A)= 0.950 ACRES RUNOFF CORP. (C) 2 YEAR 10 YEAR 100 YEAR C 0.46 0.46 0.58 SEE SPREAD SHEET ATTACHED ON PAGE 3 TIME OF CONCENTRATION (Tc) OVERLAND TRAVEL TIME (TO LENGTH = 40 FEET SLOPE 2.00 k 2 YEAR 10 YEAR 100 YEAR C 0.20 0.201 0.25 Ti (min)- 8.47 8.47 8.00 TRAVEL TIME (TO-L/(60*V) FLOW TYPE L (ft) 400 S (1) = 1.5000 SWALE V (fpe). - 1.83 Tt(min)- 3.64 L (ft) =? S (3) = 0 NONE V (fps) = 0.00 Tt(min)- 0.00 L (ft) =? S (4) = 0 NONE V (fps) = 0.00 Tt(min)- 0.00 L (ft) _? S (i) = 0 NONE V (fps) = 0.00 Tt(min)- 0.00 L (ft) _? S (►) = 0 NONE V (fps) - 0.00 Tt(min). 0.00 L (ft) =? S = 0 NONE V (fps) = 0.00 Tt(min)- 0.00 L (ft) =? S (k) = 0 NONE V (fps) - 0.00 Tt(min)= 0.00 ALL VELOCITIES TAKEN FROM FIGURE 3-2 TOTAL TRAVEL TIME (min) = 3.64 TOTAL LENGTH = 440 L/180+10- " 12.44 > 11.64 CHOOSE LESSER , Tc =Ti+TOTAL TRAVEL TIME 2 YEAR 10 YEAR 100 YEAR Tc (min)- 12.11 12.11' 11.64 USE Tc = 12 12 11.5 INTENSITY (I) (iph) , 2 YEAR 10 YEAR 100 YEAR I = 2.38 4.17 6.62 NOTE: INTENSITIES TAKEN FROM FIGURE 3-1 RUNOFF (Q= CIA) (cfe) 2 YEAR 10 YEAR 100 YEAR Q = 1.04 1.82 3.72 CONCLUDE:SWAL6 WITH VALLEY PAN IP SLOPE IS LESS THAN 214 DESIGN PLOW = 1.33*0100.= 4.95 CPS SEE PAGE 25 A REFER TO SECTION K-K SHEAR ENGINEERING CORPORATION PAGE 25a CHANNEL CAPACITY FOR SECTION K-K PROJECT NAME: WESTFIELD PARK PUD DATE: 07/31/97 PROJECT NO. : 1005-44-94 BY : HBO SWALE DESCRIPTION:SWALS CONVEYING FLOW TO DESIGN POINT B2 _ FILE: WBSTCHAN CAPACITY.OF TRIANGULAR OR TRAPEZOIDAL CHANNEL CHANNEL CONFIGURATION: GRASSED TRIANGULAR CHANNEL LINING: GRASS Q100 (cfe) = 3.72 DESIGN FLOW (cfe)= 4.95 Da Db Dc Sc n W I (ft) (ft) (ft) (%) (ft) ---- ----- ---- (ft) ---- ---- ---- ---- 3.00 3.00 0.75 1.67 0.032 0.00 0.25 0.25 = LEFT BANK SLOPE 4.00 :1 SIDS SLOPE. (H:V) 0.25 = RIGHT BANK SLOPE 4.00 :1 SIDE SLOPS (H:V) DEPTH WIDTH AREA PERIM R 2/3 Sc 1/2 Q V (ft) (ft) (s.f.) (ft) (A/P) ------- ------- (cfe) ------- (ft/sec) ------- ------- -------------- ------- 0.75 6.00 2.25 6.18 0.51 0.13 6.88 3.06 0.50 4.00 1.00 4.12 0.39 0.13 2.33 2.33 r 0.25 2.00 0.25 2.06 0.24 0.13 0.37 1.47 - 0.00 0.00 0.00 0.00 0.00 0.13 0.00 0.00 0.663 5.30 1.76 5.47 0.47 0.13 4.95 2.92 !llYYflff#Y#!lflYfllf iflfff##ffff}flf Ylf if l######t#!!}l if Yf if 11f 11111#Y# DEPTH WIDTH AREA PERIM R 2/3 Sc 1/2 Q V (s.f.) (£t) (s.f.) (ft) .(A/P) (cfe) (ft/sec) CONCLUDE:FLOW DEPTH FOR DESIGN FLOW = 0.66 FEET FLAW DEPTH FOR DESIGN FLOW < DEPTH OF SWALE SWALE IS ADEQUATE DETENTION SHEAR ENGINEERING CORPORATION AVERAGE END AREA METHOD FOR DETENTION BASIN VOLUMES SCSNARIO:SINGLB POND ON EAST SIDS OF SENECA PROJECT :WESTFIELD PARK PUD DATE: 06/02/97 PROD. NO:1005-44-94 BY HBO LOCATION:FORT COLLINS FILE: NEWPOND NOTES :SINGLE POND LOCATED .ON BAST SIDS OF SENECA STREET INVERT ELEV. = 5094.00 FEET FIRST EVEN CONTOUR 5095.00 FEET TOP ELRV 5102.20 FEET INCREMENT 1.00 FOOT rere rr+r rrtter++ •rr++r++ rrrrrr:r +r+rr+rr rrrrrrti +r++rr++ STAGE SLEV AREA VOLUME CUM. CUM. CUM. (A2) (Vi) VOLUME VOLUME VOLUME ft ft aq ft cf cf cy ac-ft rtre+rrr rrrrrrrr rttrr+r+ •rrrrrrr rtrrr+rr •rrrrrtr rrtrrrrr 0.00 5094.00 0 0 0 -. 0 0.00 1.00 5095.00 21823 7202 7202 267 0.17 2.00 5096.00 47166 34495 41696 1544 0.96 3.00 5097.00 84115 65641 107337 3975 2.46 4.00 5098.00 107623 95869 203206 7526 4.66 5.00 5099.00 145030 126327 329532 12205 7.57 6.00 5100.00 173540 15928S 488817 18104 11.22 7.00 5101.00 187183 180362 669179 24784 15.36 8.00 5102.00 201077 194130 863309 31974 19.82 8.20 5102.20 203856 40493 903802 33474 20.75 +t•r•rrrrrrrrrrrttrrr+•errrrrrrrtrryr+rr+rrrrrrrrrtrtrr+rr++•rre TOTAL VOLUME PROVIDED WITH THIS SCENARIO = 903802 CF 20.75 ACRE-FEET POND REQUIREMENT - 714384 CF - 16.40 ACRS-PSET EXCESS VOLUME _ '189418 CF = 4.35 ACRE -PEST FOR 1.00 FOOT FREEBOARD ELEVATION = 5101.20 CF VOLUME AT ELEVATION - 5101.20 EQUALS 708005 CF = ELEVATION ® WHICH REQ'D STORAGE IS REACHED = 5101.23 PT FREEBOARD PROVIDED = 0.97 PT OVERFLOW WEIR ELEVATION = 5101.70 STORAGE PROVIDED AT OVERFLOW WEIR , 18.48 AC -FT REQUIRED STORAGE VOLUME FOR WATER QUALITY = 1.05 AC -PT REFER TO CALCULATIONS BY ANDREA PAUCETT ELEVATION W WHICH REQ'D STORAGE IS REACHED = 5096.06 FEET PAGE 1 16.25 ACRE FEET ELEVATION = 5101.20 INTERPOLATED AREA= 189962 SP 1 PT FREEBOARD ELEV ELEVATION = 5101.23 INTERPOLATED AREA= 190379 SP 100 YR WSEL ELEVATION = 5101.70 INTERPOLATED AREA= 196909 SP OVERFLOW SPILL ELEVATION ELEVATION = 5096.06 INTERPOLATED AREA= 49441 SP WATER QUALITY ELEVATION CONCLUDE:THB FREEBOARD IS r LESS THAN 1.0 FOOT BUT THE TOTAL VOLUME IS MORE THAN SUFFICIENT REQUEST VARIANCE FROM FREEBOARD REQUIREMENT SHEAR ENGINEERING CORPORATION PAGE: 2 MODEL OUTLET BOX WITH WHIR PLOW INTO BOX PROTECT: WESTFIELD PARK P.U.D. DATE: 10/01/97 PROJECT NO 1005-44-94 BY HBO PROTECT LOCATION :WEST HORSBTOOTH ROAD PILE NEWPOND PORT COLLINS INPUT FOR OUTLET STRUCTURE MODELS PLOW OVER PRIMARY WEIR INTO OUTLET PRIMARY WHIR EMERGENCY OVERFLOW WEIR WHIR LENGTH (£t) = 16.00 WEIR LENGTH (ft) -MA WEIR INVERT (ft) = 96.00 WHIR INVERT (ft) -HA WHIR CORP. (Cw) = 2.60 WHIR CORP. (Cw) =NA 100 YR RELEASE RATH (cfe)= 2.50 TOP OF BERM (ft) = 102.20 OUTLET PIPE DIAM. (ft) _ 1.25 INIT. DELTA (ft) = 0.50 PIPE SLOPE (t) = 0.50 DELTA HEAD (ft) = 0.50 MANNINGS n = 0.013 100 YR HEEL REQUIRED (£t)= 101.23 ttrrrrrr rr rrrrr* *rrr*rrr *OUTPUT* **e*rrrr ******** ♦*rttttr rrrerrrr PIPE AREA (SP) = 1.23 WETTED PERIMETER = 3.93 FEET HYD. RAD (PT) = 0.313 FEET R�2/3 = 0.4603 • OUTLET PIPE CAPACITY = 4.57 CPS' - rttertt trt» tt rrr»rt *OUTPUT* ttt ttrr ttr to tr rr***** HEAD HEAD RLEV. OVER WEIR OVER WEIR TOTAL BLEV. WHIR PLOW WEIR PLOW PLOW ft ft cfe ft cfe cfe ft 96.00 0.00 0.00 0.00 0.00 0.00 96.00 96.50 -0.50 14.71 0.00 0.00 14.71 96.50 97.00 1.00 41.60 0.00 0.00 41.60 97.00 97.50 1.50 76.42 0.00 0.00 76.42 97.50 98.00 2.00 117.66 0.00 0.00 217.66 98.00 98.50 2.50 164.44 0.00 0.00 164.44 98.50 99.00 3.00 216.16 0.00 0.00 216.16 99.00 99.50 3.50 272.39 0.00 0.00 272.39 99.50 100.00 4.00 332.80 0.00 0.00 332.60 100.00 102.20 6.20 642.22 0.00 0.00 642.22 102.20 96.153 0.15 2.49 0.00 0.00 2.49 96.15 96.154 0.15 2.51 0.00 0.00 2.51 96.15 WEIR FLOW EQTN. : CwLH^3/2 CONCLUDB:THB WEIR PLOW INTO THE BOX REACHES THE RELEASE RATE AT A HEAD OF 0.15 FEET OVER THE WEIR. THEREFORE WE -CAN ASSUME THAT THE ORIFICE WILL CONTROL RELEASE AT ELEVATION 96 BECAUSE THE BOX WILL PILL UP IN LESS THAN A MINUTE BOX VOLUME = 2*4*4 - 32.00 CP 32 CP/2.5CFS . 12.80 SECONDS SHEAR ENGINEERING CORPORATION PAGE: 3 MODEL AFFECT OF WATER QUALITY DEVICE ON OUTFLOW FROM POND PROJECT: WESTFIELD PARK P.U.D. DATE: 10/01/97, PROTECT NO 1005-44-94 BY MEO NOTE: ASSUME ZERO (0) RELEASE UP TO PILE: NEWPOND ELEVATION 96 INPUT FOR OUTLET STRUCTURE LOWER ORIFICE DIAM. (ft) = 0.48 EMERGENCY OVERFLOW WEIR . LOWER ORIFICE INV. (ft) = 94.00 WEIR LENGTH (ft) = 20.00 LOWER ORIFICE COEF. (Cl) = 0.65 WEIR INVERT (ft) = 101.70 PRIMARY WEIR LENGTH (£t) = NA WEIR COEF. (Cw) = 2.60 WEIR INVERT (ft) = NA TOP OF BERM (ft) = 102.20 WEIR COEF. (Cw) = HA INIT. DELTA (ft) = 1.00 100 YR RELEASE RATE (cfe)= 2.50 DELTA MR= (ft) = 1.00 OUTLET PIPE DIAM. (ft) 1.25 100 YR HEEL REQUIRED (ft)- 101.23 PIPE SLOPE (4) = 0.50 MANNINGS n 0.013 +rrrxrrr ++++r+r+ rrrrr:tr *OUTPUT* rrrxrrrr +e iietxx :rrrrrrr •xrxxxrr PIPE AREA (SP) = 1.23 WETTED PERIMETER = 3.93 FEET HYD. RAD (PT) = 0.313 PERT R^2/3= 0.4603 OUTLET PIPE CAPACITY = 4.57 CPS LOWER ORIFICE AREA (A) = 0.1810 SQUARE DEBT i trxrrr rrrrr t+ rrrrrrr *OUTPUT* rti+xxr rrrrrtr rx rrrrr EMERGENCY OVERFLOW HEAD HEAD ELEV. OVER LOWER OVER WEIR TOTAL ELEV. CUM LOWER ORIFICE WEIR PLOW PLOW VOLUME ORIFICE PLOW ft ft c£e ft cfe cfe ft ac-ft 94.00 0.00 0.00 0.00 0.00 0.00 94.00 0.00 95.00 0.76 0.00 0.00 0.00 0.00 95.00 0.17 96.00 1.76 1.25 0.00 0.00 1.25 96.00 0.96 97.00 2.76 1.57 0.00 0.00 1.57 97.00 2.46 98.00 3.76 1.83 0.00 0.00 1.83 98.00 4.66 99.00 4.76 2.06 0.00 0.00 2.06 99.00 7.57 100.00 5.76 2.27 0.00 0.00 2.27 100.00 11.22 101.00 6.76 2.45 0.00 0.00 2.45 101.00 15.36 102.00 7.76 2.63 0.30 8.54 11.17 102.00 19.82 102.20 7.96 2.66 0.50 18.38 21.05 102.20 20.75 101.20 6.96 2.49 0.00 0.00 2.49 101.20 16.25 101.23 6.99 2.50 0.00 0.00 2.50 101.23 16.40 101.70 7.46 2.58 0.00 0.00 2.58 101.70 18.48 rrrrxrre rr+tirrr rr rtrirr rrrrtrrt rttt ttii i++rrrrr rttrrttr rrrrtttt ORIFICE EQUATION: CA(29H)"1/2 WEIR PLOW SQTN. : CWLHA3/2 NOTE: HEAD OVER ORIFICE = HEAD OVER CENTER OF ORIFICE CONCLUDE:POND AND OUTLET STRUCTURE ARE ADEQUATE WITH WATER QUALITY STRUCTURE IN PLACE STREETS' o 00 v "' J N O II 0 f II i l� 2 - Qt _ F- d lail G N uj W p in N in N N nj N M r N N O M M p W U 00 II z Q M 00 II z Q 0 W Li o a Wa o a a 0 J U a¢ U Li ? LL o C o O I - � Iq W Li z z vi 00 a Ivi vi o co Ncn p O _� 1 4- N OLn _J I1 II Li �y• i� �I �O;2 N v7 i� W o o _LJ o o 4 W Q- �� C O M N (O� g Z O w i= w -' � N � o S v L Q o o N Q N LLJ � N L1J Z Q Lnui 3 o Q CJO U W co W W x W d N N U- D N ... (N Vl CT p 0 Li N In V ° N � 00 Lq LO II ¢ w II J W CD 11 II II J w N •' ° 00 Q Q � Q Q to to w w w w CD CD .S l 1*0 . CTO--I - a W W N z M coCN z Q V Ofl, O VT W W W O O O II W O II W 4 N 0 uj —� L N o w 5 �W o = O O vi a Wp J oo ui w W 0 I I^ -r w a i t 0 o_ w o a .-- Q II O , N: ^ 00¢ LLj N 11 0 N a m . N v�i LLJ Q � `gIx °d cc Q I V ' 0 M or 0 o CDW o o F- N W a M w W �" M cq W ch� C C v ' Z V Z L J o U0. o U U Z O U Z O W F- LLJ V) 3 �. z N O N O (Ifw U LLJ > U < W m Q K to Q' V) tD fN 2 YEAR STORM (WATER DEPTH = 0.41') CURB 8 CUTTER A=0.697 S.F. ; P=2.958' ; n=0.016 ; R=A/P 0 = (1.49/n) (A) (11)2/3(s)1/2 0 v 24.76 (S)1/2 STREET A.2.100 S.F. ; P.14.786' ; n.0.016 R.A/P 0 n (1.49/n) (A) (R)2/3(s)'/2 0 = 53.23 (S)'/2 ONE HAIL STREET CAPACITY . (24.76 53.23) (S)I/2= 77.99 (S)1/2 100 YEAR STORM (WATER DEPTH = 0.93'1 CURB 8 GUTTER A=4.122 S.F. ; P-8,885' ; n.0.015 ; A.A/P 0 a (1.49/n) (A) (R)2/3(S)1/2 0 a 230.04 (S)1/2 STREET A.10.423 S.F. I P.17,156' ; n.0.016 ; R.A/P 0 = (I.A9/.) (A) (R)2/3(s),/2 0 a 696.26 (5)I/2 ONE HALF STREET CAPACITY v (730.04 4. 696.26) (S)I/2v 926.30 (S)1/2 YEAR STORM DEPTH `100 YEAR STORM DEPTH LOCAL STREET - 34' FLOWLINE TO FLOWLINE 2 YEAR STORM (WATER DEPTH . 0.48') CURB 6 GUTTER A-0.11M S.F. ; P=2.823' ; n=0.016 : R=A/P 0 = (1.49/•) (A) (R)2/3(S)1/2 . o a 3ma (S)1/2 STREET A-2.77a S.C. ; P=17.005' ; n-0.016 R=A/P 0 . (1.49/n) (A) (R)2/3(S)1/2 0 = 77.31 (S)1/2 ONE HALF STREET CAPACITY . (34,18 ♦ 77.31) (S)1/2. 1,,.AS (S)1/2 100 YEAR STORM (WATER DEPTH a 1.101 CURB 6 GUTTER A-3.182 S.F. ; P=6.323' ; n=0.016 ;'R=A/P 0 - (1.49/n) (A) (R)2/3(s),/2 0 = I67.47 (S)1/2 . T� A-16.79 S.F. ; P-24.448' ; n.0.016 ; R.A/P 0 . (1.49/n) (A) (R)2/3(S)1/2 0 a 1.217.07 (S)1/2 ONE HALF STREET CAPACITY . (187.47 4 3.217.07) (S)I/2. 1.404.55 (S)1/2 YEAR STORM DEPTH ` 100 YEAR STORM DEPTH RESIDENTIAL COLLECTOR - 50' FLOWLINE TO FLOWLINE 2 YEAR S10RM (WATER DCPIN = 0.48') CURB 6 GUTTER A=0.830 S.F. ; P=2.823' ;" n=0.016 ; R=A/P 0 e (1.49/n) (A) (R)2/3($)1/2 0 = 34.18 (s)1/2 STREET A.2.76 S.F. ; P=17.005' ; n=0.016'; R-A/P _ 0 . (1.49/n) (A) (R)2/3(S)I/ 0 = 77.31 (S)'/2 ONE HALF STREET CAPACITY = (34.16 .. 77.31) ($)I/2= 111.45 (S)1/2 YEAR STORM DEPTH 100 YEAR STORM (WATER DEPTH = 1.17') CURB & CUTTER A=4;263 S.F. ; P=6.698' ; n=0.016 ; R=A/P 0 (1.49/4) (A) (R)2/3(S)1/2 0 = 293.74 (5)1/2 TS RCET A.27.38a S.F. ; P.34.521' ; n.0.016 : R.A/P 0 v (1.49/n) (A) (R)2/3(S)1/2 0 . 2185.79 (S)1/2 OHL HALF STREET CAPACITY = (293.74 ♦ 2185.79) (S)'/2= 2479.52 (S)1/2 YEAR STORM DEPTH MAJOR ARTERIAL - 70' FLOWLINE TO FLOWLINE STREET STORM WATER CAPACITY tJ a .. o v `o Z � d" II a II .9 c� w 00 � a_ a_ NN • i N N Ilz -' �- N N .9 .' .•. I OM 0 r'M'1 c U N O I'/, I-) o U Il w II z Q No II w II z Q .II �� .. a J a. Ck�a o a W Q 4 o a W ® o U o U F— o F-- LLJo O LLI EL CDW LLJ o W (n w En w r N toU ^ U J ) i0 O to CDO c�i J �� V' �i O J C L.:LL N /1 /�c y N LL loMM c O co r 0 O O c �� I`P O O O N � OO II (V 1 u ' N II N Q II /A v' W zr I J lil Q oC w Q N O �N w 0 w oa w � z � a O O U � U w L.,J J U J J F-- —J O L'Iw O o U N o U U > Ckf U W m W N to V) 1 2 3 4 scc } 6 7 9 10 Curb — 1� 134W 12 13 14 1s 16 17 13 19 71 22 23 24 2s 26 27 23 `A o(se,\ool4\ - 94 sty-etgt� Ckvcc,�, 117- st"'x- ,-h�hc0-b - L(I Crawvv <)� J�Oh,A 4--t— = O.4s3 , cvrYcv�- God A3 !0\3e\ c A U1-7 A .z I \3Z sf z A3 P2:T:\.2&7 BY i I J D:7 IWs-49- c.,� 3 3 I OA �b16� C3Ss� + C w L)(4 Z) { �s�.c Viz)- �4 ¢ _ 0.01-7 IL rJ ,Ol6 14.31 GTS S7�Lti} Ch��iGi�� Ld C�ULJa�1 RoAn SHEAR ENGINEERING CORPORATION PAGE 2 OF 2 STREET CAPACITY PROJECT NAME: WESTFIELD PUD DATE: 11/04/97 , PROJECT NO. : 1005-44-94 BY : MHO NOTE: ALL POINTS IN SUMP CONDITION FILE: STREET ALLOWABLE HALF ACTUAL HALF DESIGN STREET STREET STREET CAPACITY REDUCT. STREET CAPACITY VERSUS Q POINT TYPE SLOPE MINOR MAJOR FACTOR MINOR Q2 MAJOR Q100 FT/PT CPS CPS CPS CPS CPS CPS 4 COLLECTOR 0.005 7.88 99.32 0.65 5.12 1.17 64.56 14.07 5 COLLECTOR 0.005 7.88 99.32 0.65 5.12 9.46 64.56 45.30 6 COLLECTOR 0.005 7.88 99.32 0.65 5.12 0.51 64.56 7.95 7 COLLECTOR 0.005 7.88 99.32 0.65 5.12 3.52 64.56 12.42 9 LOCAL 0.005 5.51 65.50 0.65 3.58 0.61 42.57 33.05 10 LOCAL 0.005 5.51 65.50 0.65 3.58 2.37 42.57 39.61 ACTUAL CAPACITY = ALLOWABLE CAPACITY X REDUCTION FACTOR CURB TYPE WIDTH & CL - FL CONVEYANCE FACTOR PL-PL GUTTER HEIGHT MINOR MAJOR PT PT COLLECTOR 50 VERTICAL 0.63 111.48 1404.55 LOCAL 36 ROLLOVER 0.45 77.99 926.3 NOTE THESE ARE FOR A LOCAL STREET WHICH IS 34' WIDE PLOWLINE TO STREET CAPACITY ADEQUACY PLOWLINB ACTUAL GENERAL NOTES: DESIGN STREET CAPACITY 1) OVERFLOW OF SENECA STREET AT DP 9 & 10 IS EXPECTED POINT MINOR MAJOR 2) CAPACITY OF STORM SEWER CANNOT BE INCREASED AT DP 9&10 4 OK OK 3) WHEN FLOW DEPTH IN SENECA STREET EXCEEDS 0.70 FEET 5 SEE NOTE OK WATER WILL OVERFLOW INTO POND 6 OK OK 4) THE PLOWS REFLECT ACTUAL PLOWS TO THE INLETS 7 OK OK 9 OK OK 10 OK OK NOTE: DESIGN POINT 5 IS IN SUMP CONDITION. A 15' TYPE R INLET WILL BE INSTALLED THE INLET IS SIZED TO HANDLE THE 10 YEAR STORM SOME OF THE FLOW TO DESIGN POINT 5 IS OVERFLOW FROM PAINTED DESERT COURT CONCLUDE:THE STREETS ARE ADEQUATE 0 APPENDIX H Erosion Control Calculations Water Quality Calculations July 21, 1997 Project No: 1005-44-94 Basil Hamdan City of Fort Collins Stormwater Utility P.O. Box 580 Ft. Collins, Colorado 80522 Re: Erosion Control Cost Estimate for Phase 1 of Westfield Park P.U.D.; Fort Collins, Colorado Dear Basil, Attached is the erosion control security deposit estimate for Phase 1 of Westfield Park P.U.D. ESTIMATE 1: 1 - area inlet haybale filters ® $75.00 each $ 75.00 4 - Gravel Inlet Filter ® $75.00 each $ 300.00 10 - Haybale barriers ® 75.00 each $ 750.00 TOTAL ESTIMATED COST: $ 1,125.00 x 1.50 $ 1,687.50 ESTIMATE 2: re -vegetate the disturbed area of 14.0 acres at $531.00 per acre $ 7,434.00 TOTAL ESTIMATED COST: $ 7,434.00 x 1.5 S 11,151.00 In no instance shall the amount of the security be less than $1,000.00. Therefore, the total required erosion control security deposit for phase 1 of Westfield Park P.U.D. will be $11,151.00. If you have any questions, please call at 226-5334. Sincerely, Mark Oberschmidt Shear Engineering Corporation BWS / meo cc: Leo Schuster, Progressive Living Jean Pakech, Stormwater Utility 4836 S. College, Suite 12 Ft. Collins, CO 80525 (970) 226-5334 FAX (970) 282-0311 July 21, 1997 Project No: 1005-44-94 Re: EROSION CONTROL SECURITY DEPOSIT REQUIREMENTS: Phase 1 of Westfield Park P.U.D.; Fort Collins, Colorado 1. An erosion control security deposit is required in accordance with City of Fort Collins policy (Chapter 7, Section C: SECURITY; page 7.23 of the City of Fort Collins Development Manual). In no instance shall the amount of the security be less than $1000.00. a. The cost to install the proposed erosion control measures for phase 1 construction is approximately $1,125.00 Refer to the cost estimate attached in Appendix L 1.5 times the cost to install the erosion control measures is $1,687.50. b. Based on current data provided by the City of Fort Collins Stormwater Utility, and based on an actual anticipated net affected area which will be disturbed by construction activity during phase 1 (approximately 14.0 acres), we estimate that the cost to re -vegetate the disturbed area will be $7,434.00 ($531.00 per acre x 14.0 acres). 1.5 times the cost to re -vegetate the disturbed area is $11,151.00. The $531.00 per acre for re -seeding sites greater than 5 acres was quoted to us by City of Fort Collins Stormwater Utility personnel. CONCLUSION: The erosion control security deposit amount required for Phase 1 of Westfield Park P.U.D. will be $11,151.00. 4836 S. College, Suite 12 Ft. Collins, CO 80525 (970) 226-5334 FAX (970) 282-031 1 July 21, 1997 Project No: 1005-44-94 Basil Hamdan City of Fort Collins Stormwater Utility P.O. Box 580 Ft. Collins, Colorado 80522 Re: Erosion Control Cost Estimate for Phase 2 of Westfield Park P.U.D.; Fort Collins, Colorado Dear Basil, SHEAR ENGINEERING CORPORATION Attached is the erosion control security deposit estimate for Phase 2 of Westfield Park P.U.D. ESTIMATE 1: 1 - area inlet haybale filters ® $75.00 each $ 75.00 3 - Gravel Inlet Filter Cal $75.00 each $ 225.00 10 - Haybale barriers ® 75.00 each $ 750.00 f TOTAL ESTIMATED COST: $ 1,050.00 x 1.50 $ 1,575.00 ESTIMATE 2: re -vegetate the disturbed area of 9.5 acres at $531.00 per acre 5,044.50 TOTAL ESTIMATED COST: $ 5,044.50 x 1.50 S 79566.75 In no instance shall the amount of the security be less than $1,000.00. Therefore, the total required erosion control security deposit for phase.2 of Westfield Park P.U.D. will be $7,566.75. If you have any questions, please call at 226-5334. Sincerely, Mark Oberschmidt Shear Engineering Corporation BWS / meo cc: Leo Schuster, Progressive Living Jean Pakech, Stormwater Utility 4836 S. College, Suite 12 Ft. Collins, CO 80525 (970) 226-5334 FAX (970) 282-031 1 February 5, 1997 Project No: 1005-44-94 Re: EROSION CONTROL SECURITY DEPOSIT REQUIREMENTS: Phase 2 of Westfield Park P.U.D.; Fort Collins, Colorado 1. An erosion control security deposit is required in accordance with City of Fort Collins policy (Chapter 7, Section C: SECURITY; page 7.23 of the City of Fort Collins Development Manual). In no instance shall the amount of the security be less than $1000.00. a. The cost to install the proposed erosion control measures for phase 2 construction is approximately $1,050.00 Refer to the cost estimate attached in Appendix I. 1.5 times the cost to install the erosion control measures is $1,575.00. b. Based on current data provided by the City of Fort Collins Stormwater Utility, and based on an actual anticipated net affected area which will be disturbed by construction activity during phase 2 (approximately 6:5 acres), we estimate that the cost to re -vegetate the disturbed area will be $5,044.50 ($531.00 per acre x 6.5 acres). 1.5 times the cost to re -vegetate the disturbed area is $7,566.75. The $531.00 per acre for re -seeding sites greater than 5 acres was quoted to us by City of Fort Collins Stormwater Utility personnel. CONCLUSION: The erosion control security deposit amount required for Phase 2 of Westfield Park P.U.D. will be $7,566.75. 4836 S. College, Suite 12 Ft. Collins, CO 80525 (970) 226-5334 FAX (970) 282-0311 July 21, 1997 Project No: 1005-44-94 Basil Hamdan City of Fort Collins Stormwater Utility P.O. Box 580 Ft. Collins, Colorado 80522 Re: Erosion Control Cost Estimate for Phase 3 of Westfield Park P.U.D.; Fort Collins, Colorado Dear Basil, Attached is the erosion control security deposit estimate for Phase 3 of Westfield Park P.U.D. ESTIMATE 1: 1000 LF of silt fence ® $3.00 per LF 1 - Gravel Inlet Filter @ $75.00 each 10 - Haybale barriers ® 75.06 each TOTAL ESTIMATED COST: ESTIMATE 2: re -vegetate the disturbed area of 6.5 acres at $531.00 per acre TOTAL ESTIMATED COST: $ 3,000.00 $ 75.00 $ 750.00 $ 3,825.00 x 1.50 $ 5,737.50 $ 3,451.50 $ 3,451.50 x 1.50 $ 5,177.25 In no instance shall the amount of the security be less than $1,000.00. Therefore, the total required erosion control security deposit for phase 3 of Westfield Park P.U.D. will be $5,177.25. If you have any questions, please call at 226-5334. Sincerely, Mark Oberschmidt Shear Engineering Corporation BW S / meo cc: Leo Schuster, Progressive Living Jean Pakech, Stormwater Utility 4836 S. College, Suite 12 Ft. Collins, CO 80525 (970) 226-5334 FAX (970) 282-0311 February 5, 1997 Project No:1005-44-94 Re: EROSION CONTROL SECURITY DEPOSIT REQUIREMENTS: Phase 3 of Westfield Park P.U.D.; Fort Collins, Colorado 1. An erosion control security deposit is required in accordance with City of Fort Collins policy (Chapter 7, Section C: SECURITY; page 7.23 of the City of Fort Collins Development Manual). In no instance shall the amount of the security be less than $1000.00. a. The cost to install the proposed erosion control measures for phase 3 construction is approximately $3825.00 Refer to the cost estimate attached in Appendix I. 1.5 times the cost to install the erosion control measures is $5737.50. b. Based -on current data provided by the City of Fort Collins Stormwater Utility, and based on an actual anticipated net affected area which will be disturbed by construction activity during phase 2 (approximately 6.5 acres), we estimate that the cost to re -vegetate the disturbed area will be $3,4851.50 ($531.00 per acre x 9.5 acres). 1.5 times the cost to re -vegetate the disturbed area is $5,177.25. The $531.00 per acre for re -seeding sites greater than 5 acres was quoted to us by City of Fort Collins Stormwater Utility personnel. CONCLUSION: The erosion control security deposit amount required for Phase 3 of Westfield Park P.U.D. will be $5,177.25. 4836 S. College, Suite 12 Ft. Collins, CO 80525 (970) 226-5334 FAX (970) 282-0311 y l (r Iw 0.1 ,: �,.,• I r�i;w. a �• .,.0 r• j i ��' \ I � ` • / • •! 1 • : ' r.'t : it '.• nyr (r I •... I •-. �' f• k. i . W eA � I •,Y •. a ��. f• ' r ..• J. - � ti r— w � 1 `� ` i d e ` �; �� , ' 1.• � 11 .• \.�� 3 IQ 1 h we. , �� 1 I • •ti J J ��� t I I 1 s .t, '+ ''tRODIBILITY ZONE.-,.'..: 1 _. .: .. q � � .. � ..{'•" v jam.. ® LOW.... 1 j1r�i� �� 1\ •a � 1 MODERATE \.��. r , HIGH ` r. I NN RAINFALL PERFORMANCE STANDARD EVALUATION PROJECT: STANDARD FORM A. COMPLETED BY: DATE: 26 5 DEVELOPED ERODIBILITY Asb Lsb Ssb Lb Sb PS SUBBAgIN ZONE (ac) (ft) M (feet) boo =A �UU�cr�� ' 1J E-"v U'� I• -c1 'rw,0ac,.\N-v- RaEq \NCLUO� 5 putiUS • �% NW GORPttt r' '1 RbW oV R-U 7ov �s,v 13-5 79,035- SA \ iF U3. 100 o 3Z-U3 0 sc MARCH 1991 8-14 DESIGN CRITERIA EFFECTIVENESS CALCULATIONS PROJECT: 5 T Ocl�, r3RNo6E. PUn STANDARD FORM B COMPLETED BY: mE u f 51`IE AR DATE: 6 6 Erosion Control C-Factor P-Factor Method Value Value Comment d-Fr I�Ayr,A, <.. gor.2.e 1Z t.0 Nl} I>J I-ItIt IiiP ii Ql \ O,U\ ROVb H�:�cYJ pl�ii 1.0 IJA SEn.mc�1 £ iltiJ ',J ol, - TJdT IN �0'11W �d �0•A d Ul 1 . U MAJOR PS SUB AREA BASIN ($) BASIN (Ac) CALCULATIONS Son.IRaor-fWRALT ROUF�R60&0fCN610 SOIL . [o,ol x (, �.37 )+ I,0X(3,9-y) 11,56=0.3[t1 Z p = O.Sx p.$x O.S x I,u x 8.37) o.ti(3.55) II = U31o9 =40 db i`il c— (0.o,(5.54)+ I,ox�z3�)�,51 s 0306L 1° = o.?xU,%u 0,5xCC t 0.Ii(3.55)51 = 033 V EfF = I- .30"'A -S!S491x10(j ac 4,(j!; G (o(Z.B�) + p = 03)to.%A.0,S i CFr` (I-.3U5$X,31o,]X100 =' q0`�-I•/, CCo.01(1.05)+ 1,0x(0.46)a/15S = 0, 3G3Y 6.3Z x((1.�x►��+5)co.,6��J1,s5 0,3)05, EFF_ �l- ,3038><,31u5�k►oU� �����, 3 C= 0.310�- E�,3t0a'xlo0 MARCH 1991 8.15 DESIGN CRITERIA ZIZ EFFECTIVENESS CALCULATIONS PROJECT: 5 i0 C k STANDARD FORM B COMPLETED BY: rnE o S\N < A'C Er4 G, nv EEA wN �7 DATE: Erosion Control C-Factor P-Factor Method Value Value Comment MAJOR PS 'SUB AREA BASIN BASIN (Ac) CALCULATIONS C�- Gc�.�l�cat�� a p = C c►.���,��) � � .��c.z��� logs = o.�,� a� EFF - �- . Oy1 g x,-00�1x100 F0•7111 Ovcgku eF i- MARCH 1991 8-15 DESIGN CRITERIA SHEAR ENGINEERING CORPORATION PAGE 1 OF 2 MODEL OVERFLOW ® DP 4 ' ' PROJECT: WESTFIELD PARK DATE: 06/10/97 PROTECT NO : 1005-44-94 BY HBO FILE: RIPRAP NOTE: ALLOW UP TO 1 FOOT FLOW DEPTH AT FLOWLINB - SET MAX SPILL ELEV ASSUME THAT SPILL WILL OCCUR AT TBW ® LOW POINT WEIR LENGTH 2((MAX SPILL-TEW)/SLOPS) INPUT FOR OVERFLOW WEIR BROADCRESTBD WEIR INFO WHIR INV. (ft) = 4.42 FLOWLINB BLEV ® LOW POINT 3.75 WHIR LENGTH(ft) = 132.00 TBW BLEV ® LOWPOINT 4.42 WEIR COBF. (Cw) = 2.60 CL BLEV. Q LOWPOINT = 4.38 INIT. DELTA'(£t) = 0.03 MAX SPILL BLEV - TBW = 0.33 DELTA HEAD (ft) = 0.05 FLOWLINB SLOPE = 0.005 100 YEAR OVERFLOW AMOUNT = 34.51 MAX SPILL BLEV (ft) = 4.75 +t+r*rr* t*r *r+r+ ++++*r++ *OUTPUT* HEAD OVER WHIR WHIR BLEV. WEIR FLOW LENGTH ft ft cfe £t , 4.42 0.00 0.00 0.00 4.45 0.03 1.78 12.00 -- 4.50 0.08 7.77 32.00 4.55 0.13 16.09 52.00 4.60 0.18 26.21 72.00 4.65 0.23 37.86 92.00 4.70 0.29 50.85 112.00 4.64 0.22 - 35.41 88.00 APPROXIMATE FLOW DEPTH t ttrttt tt t•ttt tt ttttt BROADCRHSTBD WEIR FLOW EQUATION CWLH-3/2 WEIR LENGTH = 2*((HEAD/SLOPS) CONCLUDS:RIPRAP THE BANK A MINIMUM OF 88.00 FEET CENTERED AT THE INLET BUILD RIPRAP A TOTAL OF 100.00 FEET CENTERED AT THE INLET D50 = 12.00 INCHES SHEAR ENGINBBRING CORPORATION PAGE 1 OF 2 MODEL OVERFLOW ® DP 6 PROJECT: WESTFIELD PARK DATE: 06/10/97 PROJECT NO 1005-44-94 BY HBO FILE: RIPRAP NOTE: ALLOW UP TO 1 FOOT FLOW DEPTH AT FLOWLINE - SET MAX SPILL ELEV ASSUME THAT SPILL WILL OCCUR AT TBW W LOW POINT WEIR LENGTH - 2((MAX SPILL-TBW)/SLOPR) INPUT FOR OVERFLOW WEIR BROADCRESTED WEIR INFO WEIR INV. (ft) WEIR LENGTH(ft) _ WHIR COEF. (Cw) _ INIT. DELTA (ft) _ DELTA HEAD (ft) _ 100 YEAR OVERFLOW AMOUNT = 4.22 FLOWLINS BLEV @ LOW POINT = 3.55 132.00 TBW ELEV ® LOWPOINT - 4.22 2.60 CL ELEV. ® LOWPOINT = 4.18 0.03 MAX SPILL BLEV - TBW = 0.33 0.05 FLOWLINS SLOPE = 0.005 1.55 MAX SPILL ELEV (ft) = 4.55 ******** *err rr*♦ rrrrrrrr *OUTPUT* rrrrrrrr ******** rrrrrrrr rrrrrrrr *******r HEAD OVER WEIR WHIR ELEV. WHIR FLOW LENGTH £t ft cfe ft 4.22 0.00 0.00 0.00 4.25 0.03 1.78 12.00 4.30 0.08 7.77 32.00 4.35 0.13 16.09 52.00 4.40 0.18 26.21 72.00 4.45 0.23 37.86 92.00 4.50 0.28 50.85 112.00 4.25 0.03 1.78 12.00 APPROXIMATE FLOW DEPTH r rrr**r •***rrr r*rr**r **trr*r ' BROADCRESTHD WHIR FLOW EQUATION CWLHA3/2 CONCLUDE:RIPRAP THE BANK A MINIMUM OF 12.00 FEET CENTERED AT THE INLET BUILD RIPRAP A TOTAL OF 20.00 FEET CENTERED AT THE INLET D50 12.00 INCHES Table 813 C-Factors and P-Factors for Evaluating EFF Values. Treatment C-Factor P-Factor BARE SOIL Packedand smooth................................................................ 1.00 1.00 Freshlydisked........................................................................ 1.00 0.90 Roughirregular surface........................................................... 1.00 0.90 SEDIMENT BASIN/TRAP................................................................. 1.00 0.50" STRAW BALE BARRIER, GRAVEL FILTER, SAND BAG ........................ 1.00 0.80 SILT FENCE BARRIER..................................................................... 1.00 0.50 ASPHALT/CONCRETE PAVEMENT ................................................... 0.01 1.00 ESTABLISHED DRY LAND (NATIVE) GRASS ........................... See Fig. 8-A 1.00 SODGRASS................................................................................. 0.01 1.00 TEMPORARY VEGETATION/COVER CROPS .................................... 0.45121 1.00 HYDRAULIC MULCH @ 2 TONS/ACRE........................................... 0..1013' 1.00 SOIL SEALANT....................................................................0.01-0.60"1 1.00 EROSION CONTROL MATS/BLANKETS............................................ 0.10 1.00 GRAVEL MULCH Mulch shall consist of gravel having a diameter of approximately 1 /4" to 1 1 /2". and applied at a rate of at least 135 tons/acre. .. ........... 0.05 1.00 HAY OR STRAW DRY MULCH After olantino orass seed, apply mulch at a rate of 2 tons/acre (minimum) and adequately anchor, tack or crimp material into the soil. Slope M 1 to 05.............................................................................0.06 1.00 6 to 10.............................................................................0.06 1.00 11 to 15............................................................................. 0.07 1.00 16 to 20............................................................................. 0.11 1.00 21 to 25............................................................................. 0.14 1.00 25 to 33.............................................................................0.17 ... 1.00 NOTE: Use of other C-Factor or P-Factor values reported in this table must be substantiated by documentation. (1) Must be constructed as the first step in overlot grading. (2) Assumes planting by dates identified in Table 11-4, thus dry or hydraulic mulches are not required. (3) Hydraulic mulches shall be used only between March 15 and May 15 unless irrigated. (4) Value used must be substantiated by documentation. MARCH 1991 8-6 DESIGN CRITERIA Ur-ba� b . i r, r -ViOI tS a. crc-s n i fC1 rD LAG A. Pxs -70 _rrFcr, ►) f�rcu = 20 acres re �,=F.CliY r,ll FCnqqo = `}�.�c� rw /�rrf. IQ G . &Sit\ -72 CWa}��1�� Afrn = S3S ac rcb % imp. -79 vy� art, �• Sin %�- (Wcsr lud ftr'e ^ 9-69 au-cb /O irnn. L6 2oC.►$)-; `��.Sr�-►�) ; 5.35(:44 9.o3C`t4)ls.o�49-)f ���.%6 96 07 = D.24s LA,- 2s � ?6- O val'rry C r-f-4— 4 '�- i s 9G e-7 l- o5 L �{ l2 1+ curves- weld Pa—k \Nr�4 ej owa po-, I. os R G 4� 1 S Ar.5 - c e,. sD96 = 2 f e{- 0� d.Rfp-� DRAINAGE CRITERIA MANUAL (V. 3) STORMWATER QUALITY MANAGEMENT U m t N m m cc A v m Cr m cc A 51 0 Extenc 10-HOL ed De r Drai entior time Basi (Dry) D 1 tents -Hour n Pon Drain s (W(t) Time a -- 0 10 20 30 40 50 60 70 .80 90 100 Percent Impervious Area in Tributary Watershed Source:Urbanos, Guo,Tucker (1989) Note: Watershed inches of runoff shall apply to the entire watershed tributary to the BMP Facility. FIGURE 5-1. WATER QUALITY CAPTURE VOLUME (WQCV) 9-1-1992 UDFCD G 1 4o hY-. TY3-rN Drr-rIf c. V\Ole, crv, r:u.r fz Y) rl�cvrGFJ aza pecrow use g" r, s<r hOlcs pet- r�� DRAINAGE CRITERIA MANUAL(V. 3) 2. z 0.02 0.01 0.02 STRUCTURALBMPs SOLUTION: Required Area per Row 1.75 in? Vi i I 0.04 0.06 0.10 0.20 0.40 0.60 1.0 2.0 I 4.0 6.0 7 Required Area per Row (in.2) 12 I n Source: Douglas County Stone Dra nage and Technical Criteria, 1966. FIGURE 5-3. WATER QUALITY OUTLET SIZING: DRY EXTENDED DETENTION BASIN WITH A 40-HOUR DRAIN TIME OF THE CAPTURE VOLUME Rev. 3-1-1994 UDFCD ` DRAINAGE CRITERIA.MANUAL (V. 3) STRUCTURAL BMPs Removable & Lockable Threaded Ca P Overflow Grate for Larger Storms Stiff Steel Screen for Water Quality Capture Trash Skimmer Volume Level Open on Top ;�:� & Bottom Perforated Holes•':; 4' Above Permanent Pool : u �; ;Y`• r Permanent Pool Level �' 4 s; '• Rs 2feeLt Rs > 4D of Riser Permanent Pool Trash Skimmer ` ' Pond Bottom See Detail Drain Valve Access Pit Outlet Pipe—= Water Quality (min. 3 ft) Riser Pipe (See Detail) Notes: 1. Altemate designs are acceptable as long as the ' - h draulics provides the required emtying limes. 2. Use trash skimmer screens of stiff green steel Size Base to Prevent - material to protect perforated riser. Must extend from the top of the riser to 2 ft. below the OUTLET WORKS Hydrostatic Uplift "1 permanent pool level. NOT TO SCALE Notes: 1. Minimum number of holes - 8 2. Minimum hole diameter - 1/8' Dia. I , 1 1-12' diameter Air Rows Vent in Threaded Cap Water Quality Outlet Holes O O O 4' O O O 4- Ductile Iron or Steel Pipe WATER QUALITY RISER PIPE NOT TO SCALE Maximum Number of Perforated Columns Riser Diameter Hole Diameter, inches 1/4' 1/2' 3/4- 1' (in.) 4 8 e 6 12 12 9• 8 16 16/ 12 8 10 20 20 14 10 12 24 24 18 12 Hole Diameter Area (in.) (in. 2) 1/8 0.013 1/4 0.049 3/8 0.110 112 0.196 5/8 0.307 3/4 0.442 7/8 0.601 1 0.785 FIGURE 6-2. WATER QUALITY OUTLET FOR A WET EXTENDED DETENTION BASIN 9-1-1992 UDFCD u APPENDIX III Supporting exhibits, figures, tables, etc. Figure 3-1; City of Ft. Collins Rainfall Intensity Duration Curve Figure 3-2; Estimate of Average Flow Velocity for Use with the Rational Formula Table 3-3; Rational Method Runoff Coefficients for Composite Analysis Table 3-4; Rational Method Frequency Adjustment Factors Figure 4-2; REDUCTION FACTOR FOR ALLOWABLE GUTTER CAPACITY Fig 5-2 Nomograph for Capacity of Curb Opening Inlets in Sumps Fig 5-3; CAPACITY OF GRATED INLET IN SUMP Table 4 Circular Pipe Flow Capacity for Mannings 'n' = 0.012 :.`. Table 5 Circular Pipe Flow Capacity for Mannings 'n' = 0.013 No Text DRAINAGE CRITERIA MANUAL'';fi' RUNOFF 5C F 20 z w U W 10 z w a .. . . O0 5 U) w CO) 3 O U 2 w 3 1 .5 NUNN milli 1111 I ME ��ra■■►� ii■ID ■I� I■■■■�I. MFAW C�:CCC,�=CNo EON. .Z •s •0 1 2 3 5 10 20 VELOCITY IN FEET PER SECOND FIGURE 3-2. .ESTIMATE OF AVERAGE FLOW VELOCITY FOR USE WITH THE RATIONAL FORMULA. *MOST FREQUENTLY OCCURRING "UNDEVELOPED" LAND SURFACES IN THE DENVER REGION. REFERENCE: "Urban Hydrology For Small Watersheds" Technical Release No. 55, USDA, SCS Jan. 1975. 5 =1-84 URBAN DRAINAGE & FLOOD CONTROL DISTRICT 3.1.6 Runoff Coefficients The runoff coefficients to be used with the Rational Method referred to in Section 3.2 'Analysis Methodology" can be determined based on either zoning classifications or the types of surfaces on the drainage area. Table 3-2 lists the runoff coefficients for the various types of zoning along with the zoning definitions. Table 3-3 lists coefficients for the different kinds of surfaces. Since the Land Development Guidance System for Fort Collins allows land development to occur which may vary the zoning requirements and produce runoff coeffi- cients different from those specified in Table 3-2, the runoff coefficients should not be based solely on the zoning classifications. The Composite Runoff Coefficient shall be calculated using the following formula: C = (s CIA;)/At Where C = Composite Runoff Coefficient C; = Runoff Coefficient for specific area A; A; = Area of surface with runoff coefficient of C; n = Number of different surfaces to be considered At = Total area over which C is applicable; the sum of all A; s is equal to At Table 3-2 RATIONAL METHOD RUNOFF COEFFICIENTS FOR ZONING CLASSIFICATIONS Description of Area or Zoning Coefficient Business: BP, BL........................................................................................ 0.85 Business: BG, HB, C.................................................................................. 0.95 Industrial: IL, IP.................................................................................................. 0.85 Industrial: IG............................................................................................... 0.95 Residential: RE, RLP................................................................................... ... 0.45 Residential: RL, ML, RP............................................................................. 0.50 Residential: RLM, RMP................................................................................ .... 0.60 ..Residential: RM, MM.................................................................................. 0.65 Residential: RH.......................................................................................... 0.70 Parks, Cemeteries. ..................................................................................... 1 .. 0.25 Playgrounds............................................................................................... 0.35 RailroadYard Areas................................................................................... 0.40 UnimprovedAreas...................................................................................... 0.20 Zoning Definitions R-E Estate Residential District — a low density residential area primarily in outlying areas with a minimum lot area of 9,000 square feet. R-L Low Density Residential District — low density residential areas located throughout the City with a minimum lot area of 6,000 square feet. R-M Medium Density Residential District — both low and medium density residential areas with a minimum lot area of 6,000 square feet for one -family or two-family dwellings and 9,000 square feet for a multiple family dwelling. R-H High Density Residential District — high density residential areas with a minimum lot area of 6,000 square feet for one -family or two-family dwellings, 9,000 square feet for a multiple family dwelling, and 12,000 square feet for -other specified uses. R-P Planned Residential District — designation of areas planned as a unit (PUD) to pro- vide a variation in use and building placements with a minimum lot area of 6,000 square feet. R-L-P Low Density Planned Residential District— areas planned as a unit (PUD) to permit variations in use, density and building placements, with a minumum lot area of 6,000 square feet. MAY 1984 3-3 DESIGN CRITERIA R-M-P Medium Density Planned Residential District — designation for medium density areas planned as a unit (PUD) to provide a variation in use and building placements with a minimum lot area of 6,000 square feet. R-L-M Low Density Multiple Family District — areas containing low density multiple family units or any other use in the R-L District with a minimum lot area of 6,000 square feet for one -family or two-family dwellings and•9,000 square feet for multiple -family dwellings. M-L Low Density Mobile Home District — designation for areas for mobile home parks containing independent mobile homes not exceeding 6 units per acre. M-M Medium Density Mobile Home District — designation for areas of mobile home parks containing independent mobile homes not exceeding 12 units per acre. B-G General Business District — district designation for downtown business areas, including a variety of permitted uses, with minimum lot areas equal to 1 /2 of the total floor area of the building. B-P Planned Business District — designates areas planned as unit. developments to provide business services while protecting the surrounding residential areas with minumum lot areas the same as R-M. H-B Highway Business District — designates an area of automobile -orientated busi- nesses with a minimum lot area equal to 1/2 of the total floor area of the building. B-L Limited Business District — designates areas for neighborhood convenience centers, including a variety of community uses with minimum lot areas equal to two times the total floor area of the building. C Commercial District —designates areas of commercial, service and storage areas. I-L Limited Industrial District —designates areas of light industrial uses with a minimum area of lot equal to two times the total floor area of the building not to be less than 20,000 square feet. I-P Industrial Park District —designates light industrial park areas containing controlled industrial uses with minimum lot areas equal to two times the total floor area of the building not to be less than 20,000 square feet. 1-G General Industrial District — designates areas of major industrial development. T Transition District — designates areas which are in a transitional stage with regard to ultimate development. For current and more explicit definitions of land uses and zoning classifications, refer to the Code of the City of Fort Collins, Chapters 99 and 11 S. Table 3-3 RATIONAL METHOD RUNOFF COEFFICIENTS FOR COMPOSITE ANALYSIS Character of Surface Runoff Coefficient Streets, Parking Lots, Drives: Asphalt................................................................................................ 0.95 Concrete............................................................................................. 0.95 Gravel................................................................................................. 0.50 Roofs ........ .................................... 0.95 ............................................................... Lawns, Sandy Soil: Flat<2%....................................................................................... 0.1 Average2 to 7%.................................................................................. 0.15 Steep>7%.......................................................................................... 0.20 Lawns, Heavy Soil: Flat<2%............................................................................................. 0.20 Average2 to 7%.................................................................................. 0.25 Steep >7%......... :................................................................................ 0.35 MAY 1954 3-4 DESIGN CRITERIA 3.1.7 Time of Concentration In order to use the Rainfall Intensity Duration Curve, the time of concentration must be known. This can be determined either by the following equation or the "Overland Time of Flow Curves" from the Urban Storm Drainage Criteria Manual, included in this report (See Figure 3-2). Tc =1.87 (1.1 — CCf) D' 12 SI/J Where Tc = Time of Concentration, minutes S = Slope of Basin, % C = Rational Method Runoff Coefficient D = Length of Basin, feet Cf = Frequency Adjustment Factor Time of concentration calculations should reflect channel and storm sewer velocities as well as overland flaw times. 3.1.8 Adjustment for Infrequent Storms The preceding variables are based on the initial storm, that is, the two to ten year storms. For storms with higher intensities an adjustment of the runoff coefficient is required because of the lessening amount of infiltration, depression retention, and other losses that have a proportionally smaller effect on storm runoff. These. frequency adjustment factors are found in Table 3-4. Table 3-4 RATIONAL METHOD FREQUENCY ADJUSTMENT FACTORS Storm Return Period Frequency Factor (years) Cf 2 to 10 1.00 11 to25 1.10 26 to 50 1.20 51 to 100 1.25 Note: The product of C times Cf shall not exceed 1.00 3.2 Analysis Methodology The methods presented in this section will be instituted for use in the determination and/or verification of runoff at specific design points in the drainage system. These methods are (1), the Rational Method and (2) the Colorado .Urban Hydrograph Procedure (CUHP). Other computer methods, such as SWMM, STORM, and HEC-1 are allowable if results are not radically different than these two. Where applicable, drainage systems proposed for construction should provide the minimum protection as determined by the methodology so mentioned above. 3.2.1 Rational Method For drainage basins of 200 acres or less, the runoff may be calculated by the Rational Method, which is essentially the following equation: Q = CfCIA Where Q = Flow Quantity, cfs A =Total Area of Basin, acres Cf = Storm Frequency Adjustment Factor (See Section 3.1.8) C = Runoff Coefficient (See Section 3.1.6) I = Rainfall Intensity, inches per hour (See Section 3.1.4) 3.2.2 Colorado Urban Hydrograph Procedure For basins larger than 200 acres, the design storm runoff should be analyzed by deriving synthetic unit hydrographs. It is recommended that the Colorado Urban Hydrograph Procedure be used for such analysis. This procedure is detailed in the Urban Storm Drainagr Criteria Manual, Volume 1, Section 4. MAY 1984 3.5 DESIGN CRITERIA 1.0 .9 .8 .7 IL o .6 f- U Q <L Z C) .J f'- U 7 0 w .4 .3 .2 .I 0 •S-O6 F= 0-8 5.0.4% F=0.5 I I I I BELOW MINIMUM ALLOWABLE I STREET GRADE 0 2 4 6 8 10 12 14 SLOPE OF GUTTER (%) Figure 4-2 REDUCTION FACTOR FOR ALLOWABLE GUTTER CAPACITY Apply reduction factor for applicable slope to the theoretical gutter capacity to obtain allowable gutter capacity. (From: U.S. Dept. of Commerce, Bureau of Public Roads, 1965) MAY 1984 4-4 DESIGN CRITERIA 1.0 12 5 10 4 .9 11 8 3 10 6 8 I- 1L 2 o 9 0 4 ►= i tL .7 (x 3 �� z 8 _ 1.5 w � � r .6 7 ark b T Exam%ey / z 1.0 _ 1.0 Z .9 .5 'g __ Example, -Part a- • 8- -- - - -- - a .8 5.5 a 0 `� Cn .6 LL- I- w 0 .7 w 5 U Z �- U- .4 z w .4 = cD .6 z 4.5 z ao 3 w - x 4 .5 4. L o 2 O c� v = . c� . f- z z � o T z .3 z z 4 w 3.5 w w a °• J 0 0 .I U. I.L. o .08 .25 3 o .06 .3 _ = o z - w w a: .04 Cr .25 _ 2.5 = w w .2 a-.03 a 3 .2 a .02 0 a = 2 a f' v a, .01 0 .15 .15 a 0 0 -- is Q 1.5 --- -- -- a .10 �- 1.2 Figure 5-2 NOMOGRPAH FOR CAPACITY OF CURB OPENING INLETS IN SUMPS, DEPRESSION DEPTH 2" Adapted from Bureau of Public Roads Nomograph MAY 1984 5-10 DESIGN CRITERIA re"; 0.7 u- 0.6 1L z 0.5 cr w - > 0.4 0 F- a- 0.3 w 0 0 ? 0.2 0 z 0 a 0.1 raze 0 1 2 3 4 5 FLOW INTO INLET PER SO. FT. OF OPEN AREA (CFS/FT2) Figure 5-3 CAPACITY OF GRATED INLET IN SUMP (From: Wright -McLaughlin Engineers, 1969) MAY 1964 5-11 DESIGN CRITERIA co F O M N t- N to .rrntot-ao O N 0 0 •� N tO O CIO co N er M (D .. 0) .• 0 N a'OMO tO O O O• t N lO tOMOiCDt- .r c7 tO O) O N O O O O N O -Ir0)M t01O 1-4 N tO 00 00 N 0 0 C; C; t- . 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N M t t IA at IA r. to t- U 4.30 tp O IA 00 C) tD tD O IA N t N O t0 CD �0 4a ooLvCC) tDo •-•Inv InOOID Lot IrA 0•�MIAN OM 0. 7 I•..: U NMtD OIt)N O.-.CD Ov TL 14. 0.U') t1A C)Wt- 00)01 ONL NNID ..< C)OIA .+tC 001At .oIt O—N VLO taT LO .IM,I1] LC4C) CD WOO CON O NlAvty LC) Nt MOO 0 0 W to M ID M d'L IA IA IAM I:rNO C)O•-y 0 ••+ N M OD • • • C; .444 t.-I CD .4 tC 00000 .-t� NNa' .+ In NCl) V NIA 0 C,] t- OD Ntto in M to .'a O M ..+ C.) oo N M Cl) M N O•-INMt to O •+ N CM t0 CfM L V'C) ILA 00 00000 .-. ..yN M O 0IAa'•O+0 00C)0) OCT) N IAstCl) Lat N O Le) in C) If) 00 t 0 .-. OD M 00 C) CV O N I"A C;Or+N 4t6 CO CO C) 0 C; . � .+ .-+ N • eC t0 O OOOLtN LCV) v tA O)t-m NN H O CD 0 tt-) 00 t0 .'+ C M O r+ t C) O Oo aY O C O.^•N MtAt LN4N 00000 . M'MO' IA OMt Ln0 0)0"r .M -0 to CV) t.� .. C N aR 00 a' M to O M . C) tCA .NI .M-I O O O .N-I O O t 614 NMtA tD 00000 N � O 11 N N t C) C) .'+ .-I O .•I L• Is O 00 O M r) rt •U C MIC�CI •O,NN MOO at' NM 0000" • C O O O •-� N M 4 O C) 66666 4 N t0 tr O'M"4r4.0' •-IM0 a'IAN 0tCD .--gat OD 0 C) CD CD 0 eN N t .r C) OD•0' t0 O . . C .-IMOOt0 L OtD 0M O O.4MIAN NMto tD 0tAC%lN �qr W CV) to •4 m M y IA tD 00 O N IA 00 a' t O CD N 00 •�.+•� .+N N N Cr) M v v AC r4 APPENDIX IV Portions of Final Design of Regional Detention Pond 247 and Outfall for the McClellands and Mail Creek Basin Portions of Foothills Basin Master Drainage Plan Report Portions of Foothills Master Drainage Plan Update and Westfield Park P.U.D. Regional Detention Pond Analysis Wesi rl�"L0 PAaX 9;'O uosEWzm INPuT 01 j31j5v b oos- 4 4' S 4 1 2 4 s_ 6 7 9 to _ V1 12 13 14 G� r # to 20 .30 40 60 70 60 90 too - tic). 4 120 I,30 TOl ele-v_ 2A sawcr #15-, Wdr 5794-. S+ 0 1 5103 $5 to 1 5104-A-6 2� I 5104.Z(O 50 1 5 105 - 40-. 2 5104Tl8 so I slot-1 6o 0 51 04-:1`b -70 L 51d4:3 $0 O 5107.05 90 1 5111-4-s tco I 5115-5 l l0 l Sits- G ISO 5113 - $ i3O Ln O_s� 9�•25 :o= o_s90 97 91 0.46 OS$ 9"1 0A7 9` S-7- I -z t:o`b 19537 o.2s 3 900 9S 92✓ 1.0 $94% 9$92-✓ o.zs 2.0t : 101.03 ✓ 0.05 2.0% los,00.✓ 0,07 2.38 i►-5o o.07 .11-.0 $ 117.67) Llo2 I-o CII-0'7 6275 13- A 5omr �.�• l0 II mN 2A 3O , +0 r 1 5D,-70, Go tooI►El20 44--F'7� 0,25 1 Q 1 �tr Q=3i-b� L REPORT OF STORM SEWER SYSTEM DESIGN USING UDSEWER-MODEL VERSION 4 DEVELOPED BY JAMES C.Y. GUO ,PHD, PE DEPARTMENT OF CIVIL ENGINEERING, UNIVERSITY OF COLORADO AT DENVER IN COOPERATION WITH URBAN DRAINAGE AND FLOOD CONTROL DISTRICT DENVER, COLORADO *** EXECUTED BY DENVER CITY/COUNTY USE ONLY ..................................... ON DATA 10-09-1997 AT TIME 09:59:13 *** PROJECT TITLE : LANDAU COURT 100 YEAR UDSEWER ANALYSIS *** RETURN PERIOD OF FLOOD IS 100 YEARS *** SUMMARY OF HYDRAULICS AT MANHOLES ------------------------------------------------------------------------------- MANHOLE CNTRBTING RAINFALL RAINFALL DESIGN GROUND WATER COMMENTS ID NUMBER AREA * C DURATION INTENSITY PEAK FLOW ELEVATION ELEVATION MINUTES INCH/HR CFS -FEET FEET ------------------------------------------------------------------------------- 1.00 0.00 0.00 0.00 31.64 5094.54 5097.10 NO 2.00 60.50 171.97 0.45 27.12 5103.85 5097.68 OK 3.00 55.50 167.22 0.49 27.12 5104.46 5097.78 OK. 4.00 50.50 161.53 0.54 27.12 5104.86 5098.21 OK 5.00 45.50 154.58 0.60 27.12 5105.00 5099.26 OK 6.00 10.00 142.35 0.70 7.00 5104.78 5099.89 OK 7.00 5.00 60.00 1.40 7.00 5104.78 5099.96 OK 8.00 10.00 142.35 0.70 7.00 5104.78 5099.79 OK 9.00 5.00 60.00 1.40 7.00 5104.78 5099.86 OK 10.00 20.50 149.41 0.64 13.12 5107.05 5100.87 OK 11.00 15.50 125.12 0.85 13.12 5111.45 5104.84 OK 12.00 10.50 77.70 1.25 13.12 5113.50 5111.34 OK 13.00 5.50 26.29 2.39 13.12 5113.50 5113.05 OK 14.00 2.68 5.00 4.90 13.12 5113.50 5113.28 OK OK MEANS WATER ELEVATION IS LOWER THAN GROUND ELEVATION *** SUMMARY OF SEWER HYDRAULICS NOTE: THE GIVEN FLOW DEPTH -TO -SEWER SIZE RATIO= .8 _ ____ ,:. SEWER MAMHOLE NUMBER SEWER REQUIRED SUGGESTED EXISTING ID NUMBER UPSTREAM DNSTREAM SHAPE DIA(HIGH) DIA(HIGH) DIA(HIGH). WIDTH ID NO. ID NO. (IN) (FT) (IN) (FT) (IN) (FT) (FT) ------------------------------------------------------------------------------- 10.00 2.00 1.00 ARCH 29.26 30.00 24.00 38.00 20.00 3.00 2.00 ARCH 29.26 30.00 24.00 38.00 30.00 4.00 3.00 ARCH 29.26 30.00 24.00 38.00 40.00 5.00 4.00 ARCH 29.26 30.00 24.00 38.00 50.00 6.00 5.00 ROUND 15.46 18.00 18.00 0.00 60.00 7.00 6.00 ROUND 15.46 18.00 18.00 0.00 70.00 8.00 5.00 ROUND 11.94 18.00 18.00 0.00 80.00 9.00 8.00 ROUND 11.94 18.00 18.00 0.00 90.00 10.00 •5.00 ROUND 17.18 18.00 18.00 0.00 100.00 11.00 10.00 ROUND 17.18 18.00 18.00 0.00 110.00 12.00 11.00 ROUND 16.63 18.00 18.00 0.00 120.00 13.00 12.00 ROUND 19.57 21.00 18.00 0.00 130.00 14'.00 13.00 ROUND 20.12 21.00 18.00 0.00 DIMENSION UNITS FOR ROUND AND ARCH SEWER ARE IN INCHES DIMENSION UNITS FOR BOX SEWER ARE IN FEET REQUIRED DIAMETER WAS DETERMINED BY SEWER HYDRAULIC CAPACITY. SUGGESTED DIAMETER WAS DETERMINED BY COMMERCIALLY AVAILABLE SIZE. FOR A NEW SEWER, FLOW WAS ANALYZED BY THE SUGGESTED SEWER SIZE; OTHERWISE, EYTSITNG SIZE WAS USED -------------------------------------------- SEWER DESIGN FLOW NORMAL NORAML 7---------------------------------- CRITIC CRITIC FULL FROUDE COMMENT ID FLOW Q FULL Q DEPTH VLCITY DEPTH VLCITY VLCITY NO. NUMBER CFS CFS FEET FPS FEET FPS FPS ------------------------------------------------------------------------------- 10.0 27.1 31.7 1.84 6.80 1.76 8.33 5.17 0.92 V-OK 20.0 27.1 31.7 1.84 6.80 1.76 7.14 5.17 0.92 V-OK 30.0 27.1 31.7 1.84 6.80 1.76 7.14 5.17 0.92 V-OK 40.0 27.1 31.7 1.84 6.80 1.76 7.14 5.17 0.92 V-OK 50.0 7.0 10.5 0.89 6.38 1.02 21.12 3.96 1.30 V-OK 60.0 7.0 10.5 0.89 6.38 1.02 5.45 3.96 1.30 V-OK 70.0 7.0 21.0 0.60 10.67 1.02 5.45 3.96 2.81 V-OK 80.0 7.0 21.0 0.60 10.67 1.02 5.45 3.96 2.81 V-OK 90.0 13.1 14.9 1.09 9.51 1.34 4.21 7.42' 1.65 V-OK 100.0 13.1 14.9 1.09 9.51 1.34 7.89 7.42 1.65 V-OK 110.0 13.1 16.2 1.02 10.23 1.34 7.89 7.42 1.88 V-OK 120.0 13.1 10.5 1.50 7.42 1.34 7.89 7.42 0.00 V-OK 130.0 13.1 9.8 1.50 7.42 1.34 7.89 7.42 0.00 V-OK FROUDE NUMBER=O INDICATES THAT A PRESSURED FLOW OCCURS ---------------------------------------------------------------------- SEWER SLOPE INVERT ELEVATION BURIED DEPTH COMMENTS NUMBER UPSTREAM DNSTREAM UPSTREAM DNSTREAM % (FT) (FT) (FT) (FT) ---------------------------------------------------------------------- 10.00 0.50 5095.25 5094.53 6.60 -1.99 NO 20.00 0.50 5095.46 5095.35 7.00 6.50 OK 30.00 0.50 5095.91 5095.55 6.95 6.91 OK 40.00 0.50 5096.61 5096.01 6.39 6.85 OK 50.00 1.00 5096.87 5096.55 6.41 6.95 OK 60.00 1.00 5096.87 5096.86 6.41 6.42 OK 70.00 3.96 5097.42 5097.10 5.86 6.40 OK 80.00 3.96 5097.42 5097.38 5.86 5.90 OK 90.00 2.00 5099.53 5097.11 6.02 6.39 OK 100.00 2.00 5103.50 5099.63 6.45 5.92 OK 110.00 2.38 5110.00 5103.54 2.00 6.41 OK 120.00 1.00 5110.57 5110.20 1.43 1.80 NO 130.00 1.00 5110.57 5110.56 1.43 1.44 NO OK MEANS BURIED DEPTH IS GREATER THAN REQUIRED SOIL COVER OF 2 FEET *** SUMMARY OF HYDRAULIC GRADIENT LINE ALONG SEWERS i. ------------------------------------------------------------------------------- SEWER SEWER SURCHARGED CROWN ELEVATION WATER ELEVATION FLOW ID NUMBER LENGTH LENGTH UPSTREAM DNSTREAM UPSTREAM DNSTREAM CONDITION FEET FEET FEET FEET FEET FEET ------------------------------------------------------------------------------- 10.00 144.80 31.74 5097.25 5096.53 5097.68 5097.10 SUBCR 20.00 22.40 22.40 5097.46 5097.35 5097.78 5097.68 PRSS'ED 30.00 72.40 72.40 5097.91 5097.55 5098.21 5097.78 PRSS'ED 40.00 120.90 47.56 5098.61 5098.01 5099.26 5098.21 SUBCR 50.00 31.60 31.60 5098.37 5098.05 5099.89 5099.26 PRSS'EP 60.00 1.00 1.00 5098.37 5098.36 5099.96 5099.89 PRSS'EL 70.00 8.00 8.00 5098.92 5098.60 5099.79 5099.26 PRSS'ED 80.00 1.00 1.00 5098.92 5098.88 5099.86 5099.79 PRSS'ED 90.00 120.90 23.07 5101.03 5098.61 5100.87 5099.26 JUMP 100.00 193.40 0.00 5105.00 5101.13 5104.84 5100.87 JUMP 110.00 271.60 0.00 5111.50 5105.04 5111.34 5104.84 JUMP 120.00 37.34 37.34 5112.07 5111.70 5113.05 5111.34 PRSS'ED 130.00 1.00 1.00 5112.07 5112.06 5113.28 5113.05 PRSS'ED PRSS'ED=PRESSURED FLOW; JUMP=POSSIBLE HYDRAULIC JUMP; SUBCR=SUBCRITICAL:FLOW *** SUMMARY OF ENERGY GRADIENT LINE ALONG SEWERS ------------------------------------------------------------------------------- UPST MANHOLE SEWER JUNCTURE LOSSES DOWNST MANHOLE SEWER MANHOLE ENERGY FRCTION BEND BEND LATERAL LATERAL MANHOLE ENERGY ID NO ID NO. ELEV FT FT K COEF LOSS FT K COEF LOSS FT ID FT ---------------------------------------------- 10.0 2.00 5098.10 1.00 0.00 --------------------------------- 0.00 0.00 0.00 1.00 5097.10 20.0 3.00 5098.20 0.08 0.05 0.02 0.00 0.00 2.00 5098.10 30.0 4.00 5098.63 0.26 0.40 0.17 0.00 0.00 3.00 5098.20 40.0 5.00 5099.68 1.02 0.07 0.03 0.00 0.00 4.00 5098.( 50.0 6.00 5100.14 0.14 1.32 0.32 0.00 0.00 5.00 5099.6., 60.0 7.00 5100.20 0.00 0.25 0.06 0.00 0.00 6.00 5100.14 70.0 8.00 5100.03 0.04 1.32 0.32 0.00 0.00 5.00 5099.68 80.0 9.00 5100.10 0.00 6.25 0:06 0.00 0.06 8.00 5100.03 90.0 10.00 5101.72 1.79 0.06 0.05 0.25 0.20 5.00 5099.68 100.0 11.00 5105.69 3.91 0.07 0.06 0.00 0.00 10.00 5101.72 110.0 12.00 5112.19 6.44 0.07 0,.06, 0.000.00 11.00 5105.69 0.0 13.00 5113.90 0.58 1.32 1.13' 0.00- 0.00 12.00 5112.19 �30.0 14.00 5114.13. 0.02 0.25 0.21 0.00 0.00 13.00 5113.90 BEND LOSS =BEND K* FLOWING FULL VHEAD IN SEWER. LATERAL LOSS= OUTFLOW FULL VHEAD-JCT LOSS K*INFLOW FULL VHEAD FRICTION LOSS=O MEANS IT IS NEGLIGIBLE OR POSSIBLE ERROR DUE TO JUMP. FRICTION LOSS INCLUDES SEWER INVERT DROP AT MANHOLE NOTICE: VHEAD DENOTES THE VELOCITY HEAD OF FULL FLOW CONDITION. A MINIMUM JUCTION LOSS OF 0.05 FT WOULD BE INTRODUCED UNLESS LATERAL K FRICTION LOSS WAS ESTIMATED BY BACKWATER CURVE COMPUTATIONS. 0 FINAL DESIGN OF REGIONAL DETENTION POND 247 AND OUTFALL FOR THE McCLELLANDS AND MAIL CREEK BASIN FORT COLLINS, COLORADO October 26, 1994 Prepared for: Client: City of Fort Collins Stormwater Utility 235 Mathews P.O. Box 580 Fort Collins, Colorado 80522 Prepared by: RBD, .Inc. Engineering Consultants 209 S. Meldrum Fort Collins, Colorado 80521 (303) 482-5922 RBD Job No. 504-009 CLIENT herd G CO"SIL• 9r Oev. JOB NO. INC PROJECT /4 aUn �a in r i e CALCULATIONS FOR Sw/✓I M NIOo(e I%H Engineering Consultants MADE BY l(f/)C' DATEL-19-2 CHECKED BY- DATE SHEETA%OF Tri6v�arY Lyidit7 _ Soleafly fix wlot +h along •fd,a downs'l.eam Side of'a" idea 510pi q t2C{grJ�lar baiin ,71e widfh . "s ioerPen�(icu/arTw, _.... _ h_ .Overland_F/pw,._.GLriL:'fhG_b�srn.. area.CA).A. _ flow �ifi._ _ /cnyf�l CL)! diuidc; 4V cif -on fl;v-,`1;^i,6u{ar, R11A. srn.190 29,8acres . 7772 average.. rtev�a�-d, ';Icry _. :: pafh /e�5ffi is a1J/irnicima{cIr ) jro -fit. : - _- _,4 .. ree inclodcs 2. acr[s.- f*»., fRe a n 3,2aCres 1. _ . 1 _ .iT'o.•�.-(-h:e S-facK'brld9er DcvaJoPmen{' bcl'S oFwhhcl, were ' l / II prgl ally -the Fa61hr/ls Ba53n t. -- Pc+cc jcacc:,tovs_�er_siic O i _�/ael & lias77 t2 rox m4ielr //% C.ui 5� , - IN l 21-0 . ...r/1r0%- i .-._. Grvunc� Step•¢: { - QCr r„{-� . w BGcl. riapnaS .a'F .-�+ei. ,Urban.Dnw,na9G, i-.Flood:. , AMA of B, i. r,rounc� ��- ..�.;., . control .V.fs-triev f'h15 JS.tNG-., 5.(ye...L__1v . can.e�j amCG rx4UT, � ee'C uSc ..I I+a (yn, Cranes:_�741,f.eS 'aK {hc sfrce ak _ --FNA 8(•aol5,- re,91s. 29an+in , sloP� tn/o7. us rourk.5Ve 2. Didfl+ Rijn- -g��rzw.Z-7_1;;,.Iw.--in MaSlu .,Plan .. L Mas{tr Pia o yea = /Y•.3. aims Retn.1 r Cu rrC/L+ a/a LLe . i r. Mos}c� P{a n , ; - 'fi+is. cor,�eYcnce.41E..•nE�,-j'puv5; Scnec.� S•(•. ; ... t....: �.. ...: . ....(Ze'E?in . u,rrfvtf. waivt .lrl .nt aS:(f/" Plan e•F• ..---........ _ ..._ .... ..._ ...i --- -- - I {f•js. [oa,.cyancG tleni.,T' fT'orn. Stiic/dsSf• I .. y Four CLw.r�� Le s-fi, -tv ' 1550 F{ /e,- UlesibrooP .Sub. Chan'e LcMAA. 11• I 1 141 cwj QD 17 I .i i lJ' / O : at Q3 A Co 00 00 N Ot 1c) to cli FOOTHILLS BASIN (BASIN G) DRAINAGE MASTER PLAN FORT COLLINS, COLORADO Prepared for: City of Fort Collins Fort Collins, Colorado Resource Consultants, Inc. P. 0. Box Q "'Fort Collins, Colorado "80522 February 1981 Ref: 971 z cn us z(n t: Zi Ou LL- 0 z (D Wf® w 6N -PU '03 6-6N 'PU -03 I . V/' La i ON V) 4D w 0 171 -1 -J.1 PuDlia,%o Q , , ?- a BASIN CHARACTERISTICS The general location and geographical limits of the Foothills Basin are shown in Fig. 1. The basin extends from Taft Hill Road on the west to the Cache la Poudre River on the east. The southern limits of the basin are generally along Horsetooth Road, also including Warren Lake. The northern boundary of the basin extends from Horsetooth Road on the west to north of Drake Road on the eastern portions. The total drainage area is J" 5.1 square miles. The northern boundary of the basin is adjacent to the Spring Creek Basin while the southern boundary is adjacent to the McClellan's Basin in the areas west of Lemay Avenue and adjacent to the Fox Meadows Basin cast of that point. One major drainageway exists through the entire basin with -several �s ' small tributary areas. On the upper portions of the basin the drainageway ..is intercepted by. irrigation canals and at the lowest area the entire drainageway again is intercepted by the Fossil.:Creek-Reservoir Inlet Ditch. To facilitate the analysis of. the drainage conditions the basin was divided into four reaches, as follows: Reach 1 - Cache la Poudre River to the Fossil Creek Reservoir Inlet Ditch. Reach 2 - Fossil .Creek Reservoir Inlet Ditch to the Union Pacific Railroad west of Timberline Road. Reach 3 - Union Pacific Railroad to the Colorado 6 Southern Railroad east of College Avenue: Reach 4 - Colorado & Southern Railroad to the western limits of the basin at Taft Hill Road. 4 The reach divisions and detailed basin limits are shown on Figures 2 and 3. These figures show the existing areas of drainage concentration and directions of overland flow. -4- RESOURCE COH ULTWITS InC The major drainage channel within this reach of the basin begins at McClelland Drive north of Foothills Drive with a 42-inch storm sewer. This becomes a 54-inch storm sewer at College Avenue and paralllels Foothills Parkway to Stanford -Road. :At Stanford Road this storm sewer becomes an open channel which then flows easterly to the pond at Camelot Drive. This pond then releases under Camelot Drive to the pond west of Lemay Avenue which in turn releases waters.under Lemay Avenue into a major drainage .channel, through the Southmoor Village East area to the pond between Lock- wood Drive and the Union Pacific Railroad. On the western limits of the basin the Larimer County No. 2 Canal parallels McClelland Drive to Foothills. Drive; at Foothills Drive the Larimer County No. 2 Canal flows east crossing College Avenue, then flows .south and -west crossing College again near, Monroe. Drive; then proceeding south and east crossing Horsetooth Road and .College Avenue. At this point Larimer County,No..2 Canal flows. southeasterly .to a structure .which .diverts water into Warren -Lake. ,_Areas.:.within. . this. basin. -between- the ,Larimer.County No. 2 Canal and the- Colorado;&.Southern Railroadtracks .drain.directly into the Larimer .County :No. _2..Canal....The only de tent ion. facility for detaining water -before entering the canal is currently being constructed on the southwest intersection of Horsetooth Road and College Avenue. Reach 4 The upper reach of the Foothills Basin extends from the Colorado & Southern Railroad to the western limits of the basin at Taft Hill Road. As Fig. 3 indicates, two irrigation canals cross this reach of the basin. These are the New Mercer Canal and the Pleasant Valley & Lake Canal. The majority of this reach of the basin has been developed; however, several large unde- veloped parcels remain. Currently most of the drainage waters from this reach of the basin are being intercepted by two irrigation canals. On the western limits of the basin the Pleasant Valley & Lake Canal intercepts drainage water from the Imperial Estates area south of Horsetooth Road. Since no storm -water deten- tion exists from the runoff of the developed area a serious drainage Problem_ exists at this point. -9- RESOURCE COMULTkrM INC The major drainage area of Reach 4 is intercepted by the New Mercer Canal. It flows through the basin paralleling•Meadowlark Avenue to Eagle Drive, then flows southeasterly to near the intersection of Horsetooth Road and the Colorado-& Southern Railroad.. Three major detention ponds release waters into the New Mercer Canal from areas east of Shields Street. In addition, drainage waters from areas west of Shields Street are collected i in an open channel which flows from Shields Street approximately 1/4 mile north of Horsetooth Road due east into the New Mercer. Canal. The New Mercer- Canal Ditch Company has indicated.that serious drainage problems exist with the canal in this area due to the amount of drainage water it is capturing at this point. Thepotential flows entering the ditch at this point exceed the capacity of the ditch, thus the potential for overtopping during major. flows exists. Drainage from areas.east.of the -New Mercer Canal within this reach of the basin. comes primarily from the Meadowlark Subdivision area which has.a detention pond, on the southeastern I limits.of..the.development. ..This..pond releases water under the railroad track.into the-Larimer CounEy No. 2..Canal through an 18-inch pipe. ..As.has•..been presented .above, -several :drainage :problems , exist within the Foothills Basin. Therefore to adequately determine their extent and the potential for other major drainage problems, a detailed hydrologic study was conducted to quantify the drainage flows to facilitate the design of drainage improvements. HYDROLOGIC ANALYSIS The hydrology of the Foothills Basin was analyzed for existing basin conditions. Utilizing the results of this analysis various storm -water management plans were -developed for the basiri under fully developed condi- tions. This section of the report discusses the results of the hydrologic analysis for the existing basin conditions. The basin hydrology was simulated using EPA's.Storm Water Management Ye Model (SWMM), modified by the Missouri River Division of the Army Corps of Engineers. This model computes runoff utilizing overland flow and channel routing routines. -lo= RESOURCE COMULMNTS IMC Table 3 Computed Peak Flows at Various Points Within the Foothills Basin (Existing Conditions) Peak Flows (cfs) Pointy Location 2-yr 10-yr 25-yr 50-yr 100 yr A Fossil Creek Reservoir 24 230 330 420 520 Inlet Ditch at County Rd. 9 crossing — B Intersection of Drake 4 56 100 ..140 180 Rd. and County Rd. 9 C Major drainageway at 20 190 270 340 410 Fossil Creek Reservoir Inlet Ditch D North tributary drainage- 4 18 34 45 57 way at Timberline Rd. E Major drainageway at 22 180 240 280 330 Timberline Rd. F Drake Rd. at Union 13 19 48 50 62 Pacific Railroad C Ma' r d i wa at 23 180 240 280 330 �o ra page y Union Pacific Railroad It Intersection of Horsetooth 25 75 110 140 Rd. and Lemay Ave. I. Major drainagway at Lemay 82 160 200 230 Avenue J. Major drainageway at 120 260 330 390 Stanford Rd. K. Warren Lake drainageway 28 120 170 220 at Horsetooth Rd. L. Major drainageway at 5 110 140 180 Larimer County..No. 2 Canal M. Major drainageway at 28 100 140 170 New Mercer Canal N. Major drainageway at 5 70 100 140 Shields St. 0. Major drainageway at 19 78 110 140 Pleasant Vallev 6 Lake Canal 1/Tlic exact locations of these points are indicated on Figures 2 and 3 .y7lic flows for Fossil Creek Reservoir Inlet Ditch are storm -water flows only and do. not include normal ditch diversions. -14- 160 280 450 270 220 210 180 1701. thin area but would not have the capacity to carry the 100-year storm + runoff. The amount of water that would be intercepted by this canal north of the bnuin is not known; therefore provisions should be made to minimize drainage inflow..into the Larimer County No. 2 Canal within this reach of wr the bnuin. For the hydrologic analysis it was assumed that this canal would overtop at the intersection of Horsetooth Road and College Avenue. Thin drainage water.would then flow east along Horsetooth Road into Warren i. Lake (Point K, Fig. 3). Reach 4 The major drainage problems within Reach 4 are near the New Mercer .Canal (Point M, Fig. 3). Drainage waters currently enter this canal approx- imntely.1/4 mile north of Horsetooth Road. Three detention basins.and one main drainage channel are intercepted by the canal at this point. The hydrologic analysis assumed that.the canal would:overtop with a storm greater. than the 2-year.design_storm used in this -study. Table 3 shows the peak flows at .this canal for the various storm -frequencies. The current capacity of .the canal in this :area,is approximately 60.cfs. The amount of inflow that will enter the canal upstream of this basin is unknown at this time. Mother major drainage problem occurs at the Colorado b Southern Rail- road tracks approximately 1/4 mile north of Horsetooth Road. The low area at this.point currently is drained by a 12-inch pipe into the Larimer County No. 2 Canal on the east side of the railroad. The analysis indicates that if the New Mercer Canal did overtop during major storm events, the ponding of water in this area would overtop the railroad tracks and flow into the Larimer County No. 2 Canal. Analysis of the existing detention basins within this reach indicate that they have the capacity to adequately pass the 100-year storm. The major drainage flow into the New Mercer Canal is not from these detention ponds but rather from runoff of other developments in the upper reaches of the basin which do not have detention facilities. -17-. RESOURCE CON ULTPOTS INC channel on the north bank. Therefore improvements in this reach of the channel should include provisions for decreasing the velocities or providing protection to the channel to minimize erosion. Upstream of Camelot Drive the floodwater profiles indicated that the flood channel is adequate for draining the 100-year storm in this area. The bridge at Stover Street would not submerge during the 100-year storm and the apartment ,and- condominium areas between Stover Street and Stanford Road are elevated *above the 100-year floodwater levels. The completion of the hydrologic. and hydraulic analyses for existing basin conditions have indicated areas where future improvements would be necessary to minimize damages during major storm events. The next step in the completion of.the.basin master plan for the Foothills Basin was to evaluate storm -water, management plans .for fully developed .basin conditions. STORM -WATER MANAGEMENT ,ALTERNATIVES Adequate planning of _future drainage improvements for -the.Foothills Basin included an analysis .of the basin hydrology under Iully,,developed conditions. Since assumptions as to onsite detention requirements, drainage - way locations, and storm -sewer sizes affect the results of the hydrologic Analysis, several alternatives were analyzed in order to provide the maxi- mum storm drainage projection with the minimum of drainage facility con- struction. Since the storm -water management alternatives assume full development within the Foothills Basin, future land uses were assumed for this analysis. Figures in the Technical Addendum show the assumed land -use patterns for the basin. Currently the major undeveloped areas in the basin are Reaches 1 and 2 and a small portion of Reach 4.. Once future land -use conditions were determined, requirements for major drainage facilities were then analyzed. Three major management alter- natives were modeled. The first alternative assumed a minimum amount of on.qite detention in lower portions of the basin in order to determine the effect of runoff in this area on the entire basin hydrograph. Each -24- RESOURCE CONSULTANTS INC additional alternative tried to minimize the required storm -sewer and . drninngcway sizes in order to minimize the construction costs for drainage facilities. nic hydrographs for each -storm-water management alternative are pre - .sensed in Fig. 6. As can be seen, the storm -water hydrograph for the 100- year storms contains. two peaks. The first peak occurs from runoff in Reach 2 of .the basin while the.second longer -duration peak occurs as a result of floodwaters from Reaches 3.and 4 within the basin. In order to optimize. the use-of.drainage. facilities, particularly the main drainage channel, these two peaks should be as close to the same as possible. Therefore, as. additional storm -water detention was added within Reach 2, the initial peak decreased while the secondary peak increased Figures 7:and:.8- present the improvements proposed.in storm -water .- management alternative 3. Since the improvements shown.were similar for :each:of--the.three..alternatives .a-- discussion :of;differences among the.alter- natives is. presented :on a reach -by -reach basis. Table 5-shows peak flows for various points within the basin. Reach 1 Since the lower reach of the basin contributed no additional drainage water to runoff from the Foothills Basin area the only alternatives analyzed were -the locations of outfall channels to the Poudre River. Two locations were studied as possible outfall channels. The first location was parallel to the Fossil Creek Reservoir Inlet Ditch south along County Road 9, then crossed both the ditch and county road approximately 1/4 mile north of Horsetooth Road. At that point the outfall channel would parallel the Fossil Creek Reservoir Inlet Ditch where it would intercept the outfall channel for the Fox Meadows Basin. The -second possible location of an outfall channel was immediately south of Drake Road proceeding due east into the Poudre River. Both of these outfall channels would minimize the disruption to gravel mining oper- ations occurring east of County Road 9 and would provide direct -flow of 125- RESOURCE CONSU MTS.INC 1 Table 5 (Cont'd) Computed Peak Flows at Various Points Within the Foothills Basin with Improvements (Fully Developed Conditions) -- Peak Flows (cfs) Pointy Location 2-yr 10-yr 25-yr 50- R Shields St: storm sewer 45 46 46 46 S Storm sewer under Pleasant. 23 23 23 23 Valley & Lake Canal 1/Exact location is shown on Figures 7 and a. 100-yr 46 23 -30- RESOURCE CON U MTS IMC Figure 6 /00 YEAR STORM HYDROGRAPH ON MAJOR s; DRAINAGEWAY AT FOSSIL CREEK RESER VO/ R /NL ET D/ TCH. 000 Srr-' iv .4- Storm -water Monogemenl Alternative / Storm - water Monogemenl Alternative 3 .600 M Storm-water Management 500 Alternative 2 ..... G 110, / Existing Conditions 3�00 ;_.. 1200 . too -�- I r. TIME (Hours) 2 3 4 5 Cu z C _o` o U L U) CD U) m (L Z 0)CU W M LL z a'L�CY, m Cl W Z J J C Z U .T W W cc O D U) O LL W cc 0 _ 0 N w � a) w C 0 .20 l0 N 00 CO o 0 to Table 6 On -Site Detention Requirements for Foothills Basin Pond—= Location Maximum storage (ac.ft.) 1 Intersection of County Rd. 9 and 10.8 Drake Rd- 2 Pond on south drainage outfall 8.9 3 of IT n IT 0 5.5 4 �� �� �� �� �� 6.1 5 Pond east of Timberline Rd. in Sec. 29 2.1 6 it it IT of 7 To to 0 It it to 0 0 4.6 8 of IT of it n it to 0 1. 6 9 Pond north of Drake Rd. 2.9 10 To to to is 0 3.7 11 to to to of it 5.0 12 Pond south of Larimer Co. No. 2 Canal 1.3 in Sec. 36 13 Pond at corner of Horsetooth Rd. and 2.7 College Ave. 14 Pond west of College Ave. south of 1.15 Larimer Co. No. 2 Canal 15 Pond on undeveloped tract in Sec. 26 6.1 16 �� �� �� �� �� �� �� 0.8 17 Pond in Sec. 27 3.5 18 Pond at corner of Shields St. and 7.2 Horsetooth Rd. 19 Pond west of Pleasant Valley 6 Lake Canal 14.0 1/Exact locations are shown on Figures 9 and 10. Maximum outflow (cfs) 85 33 24 24 24 11 44 24 11 24 24 24 2 4 11 4 11 11 23 .._ . -36- RESOURCE CON ULTNHTS INC q c +r c o Z N U aE m O L -- CCL c c U- U Z_W z cn m ca O rn U. a cn Z O J E L- U ° cc O D (n O 0 LL cc co N .:ifi ";t Railroad track indicated that a detentiow pond in this area would not be feasible. Therefore a major storm sewer is proposed under the Colorado 5 Southern Railroad and under the Larimer County No. 2 Canal. Several alternatives were analyzed before recommending this solution including development of a major detention facility in this area. The size of the detention facility would have required the purchase of approximately 15 acres of land along with reconstruction of approximately 1,500 feet of the New Mercer Canal. With that expenditure the.peak flows would have been reduced to only about 25 percent. Therefore it is recommended that the drainageway improvements proposed be constructed and that detention facilities be constructed upstream.-of.this.area in order to minimize the 1 peak flows through these drainage facilities. Three major detention areas are proposed west of Shields Street as shown in Fig. 10; two of these would capture drainage waters from existing developments west of Shields Street and south of.Horsetooth.Road (Ponds 17, 18, and 19, Fig. 8). The largest facility would be immedigLteIX ahovp the Pleasant Valley S Lake Canal (Pond 19, Fig. g), This would can .re drainage waters from the Imperial Estates area and release them llnAA , t-Se Pleasant Valley h Lake Canal.in a 24-inch storm sewer. A second detention facility would be constructed at the corner of Shields Street and Horse - tooth Road within the current development. This detention facility would release waters into a 30-inch storm sewer along the west side of Shields Street. An additional detention facility is proposed for the currently undeveloped parcel immediately north of Horsetooth Road west of Shields Street and this would then release into the 30-inch storm sewer on Shields Street. This storm sewer would then cross Shields Street into the major drainage channel that is proposed north of Horsetooth Road. - Since many drainage improvements are proposed for the Foothills Basin, the costs were analyzed in order to develop drainage basin fees for future developments within the basin. -37-. RC50URCC CONSULTANTS INC 5. Improvements to the major drainagewa in the vicinity of Timberline Road The current culvert facilities under Timberline Road are inadequate and cause overtopping of the road during minor storm events. Construction of four 36-inch culverts under Timberline Road at this location and develop- ment of a channel east of Timberline Road through the CSU farm area should be considered prior to development occurring in this area. 6. Outfall facilities to the Poudre River The construction of the major drainage outfall.channels to the Poudre River as well as crossing structures for the Fossil Creek Reservoir Inlet Ditch should be constructed prior to the adverse impact of future develop- ment on the current drainage patterns. These facilities should be designed in .cooperation with North:Poudre Irrigation Company to assure their require- ments are met for releasing waters into Fossil Creek Reservoir Inlet Ditch. 7. North tributary storm sewer The storm :sewer along East Drake Road from the Parkwood.East pond to the major drainage channel should be constructed prior to:;improving Drake Road in this area. B. Improvement to Reach 4 These improvements include construction of detention ponds west. of Shields Street, a storm sewer along Shields Street and construction of culverts under :the .canals.and.railroad north of Horsetooth Road. These improvements should be completed only when the major drainageway below the Larimer County No. 2 Canal has been improved to adequately handle the addi- tional storm water that would occur as the result of these improvements. 9. Construction of concrete -lined channel between Lemay Avenue and Lockwood Drive These improvements should be constructed as funds are available from drainage fees collected within the basin or if a special improvements district is formed in the Southmoor Village East area to pay for these improvements. -45- .. RESOURCE CON ULTMTS INC Channel Adjacent to Horsetooth Worksheet for Irregular. Channel Project Description Project File c:lhaestadlfmw\horse.fm2 Worksheet Channel adjacent to Horsetooth Road Flow Element Irregular Channel 'Method Manning's Formula Solve For Discharge Input Data Channel Slope 0.004000 ft/ft Water Surface Elevation 5,106.89 It Elevation range: 5,104.42 ft to 5,108.39 ft. Station (ft) Elevation (ft) Start Station End Station 0.00 5,108.39 0.00 22.00 15.00 5,104.64 22.00 24.00 22.00 5,104.50 24.00 42.00 23.00 5,104.42 24.00 5,104.50 31.00 5,104.64 40.00 5,106.89 42.00 5,106.93 Results Wtd. Mannings Coefficient 0.029 Discharge 263.97 cfs Flow Area 57.59 ft' Wetted Perimeter 34.56 ft Top Width 34.00 ft Height 2.47 ft Critical Depth 5,106.34 ft Critical Slope 0.010841 ft/ft Velocity 4.58 ft/s Velocity Head 0.33 ft Specific Energy 5,107.22 ft Froude Number 0.62 Flow is subcritical. Roughness 0.035 0.012 0.035 02A0397 FkmMaster v5.13 10:24:05 AM Haestad Methods, Inc. 37 BrookB!de Road Waterbury, CT 06706 (203) 755.1666 Page 1 of 1 Tract A Channel Cross Section for Irregular Channel Project Description Project File c:\haestad\fmw\horse.fm2 Worksheet Channel adjacent to Horsetooth Road Flow Element Irregular Channel Method Manning's Formula Solve For Discharge Section Data Wtd. Mannings Coefficient 0.029 Channel Slope 0.004000 ft/ft Water Surface Elevation 5,106.89 ft Discharge 263.97 cfs 51 51 51 51 51 c 0 to 51 W 5' 5' 5' 5' 0203197 10:19:38 AM 0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 Station (ft) Haestad Methods, Inc. 37 Brookside Road Waterbury. CT 0670E (203) 75r}1666 45.0 FlovvMaster v5.13 Page 1 of 1 A, . Table Rating Table for Irregular Channel <. Project Description Project File cAhaestad\fmYAhorse.fm2 Worksheet Channel adjacent to Horsetooth Road Flow Element Irregular Channel Method Manning's Formula Solve For Discharge Constant Data Channel Slope 0.004000 ft/ft Input Data Minimum Mabmum Increment Water Surface Elevation 5,104.50 5,106.89 0.10 ft Rating Table Water Surface Elevation Wtd. Mannings Discharge Velocity (ft) Coefficient (cfs) MIS) 5,104.50 0.012 0.08 0.94 5,104.60 0.015 0.78 .1.00 5,104.70 0.022 2.70 1.17 5,104.80 0.024 5.83 1.45 5,104.90 0.025 9.92 1.72 5,105.00 0.026 14.92 1.96 5,105.10 0.027 20.77 2.17 5,105.20 0.027 27.45 2.38 5,105.30 0.027 34.95 2.56 5,105.40 0.027 43.26 2.74 5,105.50 0.028 52.37 2.90 5,105.60 0.028 62.29 3.05 5,105.70 0.028 73.00 3.20 . 5,105.80 0.028 84.52 3.34 5,105.90 0.028 96.85 3.48 5,106.00 0.028 109.99 3.61 5,106.10 0.028 123.95 3.73 5,106.20 0.028 138.74 3.85 5,106.30 0.028 154.37 3.97 5,106.40 0.028 170.83 4.08 5,106.50 0.029 188.15 4.19 5,106.60 0.029 206.32 4.29 5,106.70 0.029 225.37 4.40. 5,106.80 0.029 245.29 4.50 5,106.90 0.029 264.30 4.56 02A03)97 FbwMaster v5.13 10:15:47 AM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 2 Table Rating. Table for Irregular Channel Rating Table Water Surface Elevation Wtd. Mannings Discharge Velocity (ft) Coefficient (cfs)- (ft/s) 02)OM7 FlowMaster v5.13 10:15:47 AM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 ' (203) 755-1666 Page 2 of 2 0-1 i 35� A IGii WG�'V' EVGIu1T10�1 klo3_ A7 n 7kf, wSF-L i n _ a�,d_Q�3 n;, ,s S09-7- e3 _ -- .\dL,, 6 s rnrn F1e- -sAxc Goa DT — ;-\V No -- ._ SiAc. Is So99 14- Nv�D = 5.b6 3 = �•7 — -- Q = 2 6 c(3_@ elty. SIo4 z C 4 0 lowmn - in rarri� -- 3 Nm ®, O w \ \ f W U •y �J ' 1� �S ` W W ^ �J�' N A110013A w Z 1311n0 ¢ U m • w N011VA313} W C H r C I f131VMaV3H 10HIN03 O I cc .• a 2 O u \ �/� IX w W O l 0 I m � h x Q Z W % 3 J W in D• („) y VI 2 W JO W N > -1 I V WI LL W 10 .W W ' o ¢ �� w I x > rl U al 0. •e >. 1 ¢ (V_� x /f 3 J , ^ VI I o O ¢ \ O \ N L Wl\ i J Q 0 O o O LL S OIN N 1 —I C O 1 � 2 Q 0 0 � a � W z O.2 W O .e J 1 W In U y W ' 1-• ¢ y�� I� W 2 0 J Fi W W 2 ` n 2 J 0 81J4 = N N u LL J= W r O ¢ O _ �Q O 00J = Y N p W N co O Q¢ Z U • W mra N J J Sox C 3¢ Z _ _ o \- w (� S LLI O r O 3 r a a "W r c = J Q Y u � \ J ❑ ❑ W U y W W N Q ; Q 0 y U.J O 41 V 4 Z H W ^ Q ¢¢ Z Or Y. .. — cc T, li .. N 0 w J Jay 0 F2 < u LL A 0 u cc U�z y .. Z CO U. =SN �`QWS W O w � Z 2 U) LL O W22x L S O w =x a3¢W ¢W 0 Y Q ¢ cc V = 26 ii 4WSZr�OJeWaaW�N W W O U O YWp O ❑❑❑ > 'S1H5l•a0V 33S D4 w go a a 240 i CHART 8 12 600 11 500 EXAMPLE 10 400 8's 2' Boa 0 • 75 ale 0/8 a IScfe/ft. B 300 tntev ttw Hw 0 roar (1) 1.75 3.7 6 200 (21 1.90 3.8 (3) 2,OS 4.1 ... 7 p 100 6 O t` 80. S 2 (�) -(2) (3) 6 9 10 8 7 7 8 6 6 7 S 6 S 4 S 4 4 3 3 3 cr 2 n. 60 — 2 N H. " U SO / x t, 1.5 Z 40 / W I.S x / ... _...0 I.S _- C JQ�6 / x N � H Cr 20/ W 3 I- 1.0 I.0 i W Angle of _ H • l0 / sD latnynll p, = 10 Mara WO 8 .9 .9 K W .6 ; O O S ►(W SCALE WINCWALL W :7 .7 4 D FLARE x .6 a ¢ (1) 30• to T3- 3 (2) 90•and 13' (3) 0• (adonsions .S 2 of sides) .S .S To Ilea %cola (2) or (3) project Ilarl%antally to %Colo (I). then uu straight inclined line through .4 D and 0 scales, at reverse as Illustrated. 'ry' 8 .4 .4 6 .30 37 _ .S 35 BUREAU O! "LIC ROADS JAR, 1903 188 HEADWATER DEPTH FOR BOX CULVERTS WITH INLET CONTROL CHART 14 mmmmml 0 10 16 __.15 14 12 F; A I Z 10 9 7 20 50 40 50 Q/B 60 o 9V IVV L7V LVV LviV JVV .+ Q/B CRITICAL DEPTH BUREAU OF PUBLIC ROADS JAN.1963 RECTANGULAR SECTION 5- 38 - 194 9V IVV L7V LVV LviV JVV .+ Q/B CRITICAL DEPTH BUREAU OF PUBLIC ROADS JAN.1963 RECTANGULAR SECTION 5- 38 - 194 TABLE 12 - ENTRANCE LOSS COEFFICIENTS Outlet Control, Full or Partly Full Entrance head .loss He = ke V2 2g Type of Structure and Design of Entrance Coefficient k" Pipe. Concrete Projecting from fill, socket end (groove -end) . . . . . . . 0.2• Projecting from fill, sq. cut end . . . . . . . . . . . 0.5 Headwall or headwall and wingwalls Socket end of pipe (groove -end) . . . . . . . . . . 0.2 Square -edge . . . . .. . . . . . . . . . . . . 0.5 Rounded (radius - 1/12D) .:0.2 Mitered to conform to fill slope . . . . . . . . . . . 0.7 0.5 (F.EL� *End -Section conforming to fill slope . . . . . . . . . . Beveled edges, 33.70 or 450 bevels 0.2 Side -or slope-tapercd inlet . . ... . . . . . . . . 0.2 Pine or Pioe-Arch. Corrugated Metal Projecting from.fill (no headwall) . . . . . 0.9 Headwall or -headwall and=wingwalls square -edge . . . . . . 0.5 Mltcred to conform to fill slope, paved or unpaved slope . . . 0.7 *End -Section conforming to fill slope . . . . . . . . . 0.5 Beveled edges, 33.70 or 450 bevels . . . . . . . . . . . 0.2 Side -or slope-tapercd inlet . . . . . . . . . . . . . 0.2 Box, Reinforced Concrete Headwall parallel to embankment (no wingwalls) Square-edgcd on 3 edges . . . . . . . . . . . . . 0.5<-7 Rounded on 3 edges to radius of 1/12 barrel dimension, or beveled edges on 3 sides . . . . . . . 0.2 Wingwalls at 30°. to 75° to barrel Square -edged at crown . . . . . . . . . . . 0.4 Crown edge rounded to radius of 1/12 barrel dimension, or beveled top edge . . . . 0.2 Wingwall at 100 to 25° to barrel Square-edgcd at crown . . . . . . . . . . . . 0.5 Wingwalls parallel (extension of sides) Square-edgcd at crown . . . . . . ... . . . . . 0.7 Side -or slope -tapered inlet . . . . . . . . . . . . . 0.2 *Note: "End Section conforming to fill slope," made of either metal or concrete, arc the sections commonly available from manufacturers. From limited hydrau- lic tests they are equivalent in operation to a headwall in both llyl and outlet control. Some end sections, incorporating a closed taper in their d sign have a superior hydraulic performance. These latter sections can be - 179 APPENDIX V Phase 1 Grading Plan Drainage and Erosion Control Plan (Sheet 1) Drainage and Erosion Control Plan (Sheet 2) Offsite Drainage Exhibit - Imperial Estates oah w= EPP A� °a= By • .' Ili � �. ��'��� -- '!��' � - ; E 11 '�!.. QP M�]TjtfSEC& kRIAL �ESTAI� SUBDIVISION ICH trim I fill IiA �l p VIA;EMI I , Ell Ilk )� �-if J� E: I ` ' MIR AT DESIGN POINTS SEI &5C If 1 1� / m< .Y 1997 SHEAR ENGINEERING CORPORATION irtLf DRAINAGE &EROSION CONTROL PLAN PROJECT N0. SKEET M0. N0. OP SXEE6 Few 9°°k— cAon.. ouc rn p dlEq INC. "N0 WESTFIELD PARK P.U.D. 1005-44-94 32 39 Cam. e• = aw E,,.AeE B.W.S.PROGRESSIVE DYING STRUCTURES, FREDERICK LAND SURVEYING FORT COLLINS, COLORADO ST°c-°NS.ONG GRADING AND UIKAINA4E CENBRAL. 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MYkh wlvY Oren ryed uM4eadovn Ne eeMM nba MVOµlblare N I . \I I dN II I! _ II Oil x�mRVM.n9W. kl' o 1 f J fort All m Tel krt111.d Whll nimm, .V'tip and Mthe youninatM. mire Do aT Vwnen Nor mbn Mill murcfllrga WI'ry fro the dtrveA gwkphrtrra yafv ul 6pzh+hunkd unl etuxa m'nAum UEVLIaPEI wlmiAlnwrt: UEYLWPER vM C. the (1ny of Fore Glom amaze I ty Ne maLrtnruro ME m ri it dTw.I B. Th'e'nen+am Ne.role ShortlyvM rev 9vlry Ann, po m ti, L" mpp k ' :ftnMxAinn. _ 1�PT.R is re.""NI' n (" pm. be ♦. pxr NPn f/IRn un Rl{gfl inn. owed (o. ran L.Arod' rolW irvveml.lxll dinner Ira a IY Ju by mmiveru. AnwnO.n nS mFtm wwxiun.l.(rvxurt ._._.._ "IV • n, LEE to • .........W.......:........................................................................................ MEW ME MM, 11.0 raumve , yn 11 /r/er a I Mail 0.13 1.11 Mere v. ae u.m at.a t.aa "'a "So ........ a,u Ile'= SO We Us gas "I mllu almost moss ci lips SIM MI We � $POP, IN I a non MI n ar n .era MI ................................................................................. .... ZmPALMER was mom, I EVEN OWMIUMNEL P.M., 11 We I'M TO to "I I'll 0 or, oil, now "In In .0 zee o au aantw V. at.. I. to to to .a. .r. cr. .e. hemll Wn 9/- Da. 3,_ MEW a a,te aw annul e.. .1. .I" to W .M ex or. .r. rawur.n.. d[ RRRECYL1RAmwE [[J MI SfY I Jam e ,V rlm"m ca r aar la msrw. ro 'I'm o. n VS n WE I WE nine and m RleatwD P d &Rm Ibnm" M FwdelevaiNr . 50401) felt TcpdEam.1cvuim - 510230 fro [Wo,.O Ndlorm, provided 11 elev.ato, .30 . N75a0 - WS,M eabk fit dirlemen VMvm Provibd v elev. ]101.N IQSS We T@.Ws"Ne, felt M.mim4'd,w]MUmM' - 1640 re-h - x 4,3M,, k few Efr. - San nfro IInniM hd - 0.[S fro, I npnna - P.Kaem m 1- ate - xmd. plia u'nn Rrn Shyppipe - 0ms(M capaolwk ( oak+dive, m-1city I1 - aT/ DO,A1 an V. l�Uu he F:wli 11 er Un' R . is mock Wd PV U. ReRk^ul Coolant, Prn1AndEriia b We hn, Hal M, mi. me OR Ile lw rlL M qn loreopplo Ind And", the plan R t Fee the 10 LOSP frnberd repareILUN111 I)RAINAGEh41lVI-PENANCE NOM I. Pe"OffiC cM acleaning of the nutlet ]ttuctutewuter lqualitynttttt by the owner 6lequded to capture that ore .Inrctute fnnctiw' properly. It is m�mmen&d ilia, This mainummince ban m ] Val basis and III iR cti m to done to determine when Ha ]rein ne.k to be cleaned out. 2. Maintenance of life ranter quality outlet mr tut. will require pcaalc terminal Ff all the gravel and replacement with reed grovel. N u Inc menace that this tr done at least FOR: time every too (2) years TYPE 2 OUTLET STRUCTURE N. MEN yy� raft. wr."h 01 rINAT •or Say . xe a M,a 11 nu env o`� /moire wua-Dec lanwC\ .o =T L-�— Nreau 41 "Ur norm new. ter a.®mm W a .INMi IL ME, n~ . IRWIN man "RICE PLATE pay all 1997 Feld Book CHANNEL SECTION H-H TRACT A LO' I LOT 1 COVERED RIP RAP LININIO FOR DETENTION POND SECTION E - FLOE— nEpIH .rO .-I. LOd(INC NORTH R.R3� am as o no. Well Iw w[5 SECTION G— G LOOKING NORTH -�A u w'un I -a [[CMN A -A 7;©�"OW`" as rears 05% w MIER awe rY New INS I to 91 NI SHEAR ENGINEERING CORPORATION AND FREDERICK LAND SURVEYING WATER GUALMY OUTLET WORKS MIt I Set 14 WE ar AN MEW We am ft IN, AMM "a Rw N..• A SERUM TRASH RACK DETAR a (af.(frta[mrew wAa I J n�ao [NLL COXN[CTp :)f § - --� �' 1 �_ �.:. e •vrb-1 a �.. . �.,,. r _ toA VIP ILI- It rZ III IIW III k rl 1 51 r t, E�It V e &^� 6 , r // C ` t3;. [{{ _ z+NNs • - y-�c s s� �� •q _.i s r ' :,3+-� 000 FIF R , ~ op M LI It � s �j I �I r� �f � _� � �I$ t _ � k csf 1;• 'r, � � � �� ����r� __ ; + ��y■. 13 V �t _.-pill : y � I Ie It _ .�.l. tt I 1,'7It r low if "t t v It fi ' 5 ?r+' iry Al , F A d � ter}' { '-f ai f, -.i.� . "n ! +'� ■S�' d[aL ' ]� it It r�' 1 1 �` r.�•� tl�s i�'531- !-� ,� " . • 3�'.. � 41F 04 In Rl d •.` v 1. n y 4� fiY,YF" Y tt-• I t I >f - �, i a' 2x •.:,� `, - :.� r 1. i. 1, at r .R- r .. + ..)�'. SI ., �. . d - 'ri,,.<� tE V t van w. 1 1,1