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Home My WebLink AboutReports - Drainage - 04/23/2025 FINAL DRAINAGE REPORT FOR LIBERTY COMMON JUNIOR HIGH Lots 4, 5, 8 & 9, Prospect Industrial Park FORT COLLINS, CO Prepared for: NEENAN ARCHISTRUCTION 3325 S. Timberline Road, Suite 100 Fort Collins, CO 80525 Contact: Shelby Hinchliff Phone: 970.218.9607 Prepared by: ELEVATION CONSULTING GROUP,LTD. P.O. Box 280869 Lakewood, CO 80226 Contact: Lincoln Thomas, P.E. Phone: 303.204.5065 JN: 2024020 April 23, 2025 Final Drainage Report Liberty Common Junior High Fort Collins, Colorado ENGINNER'S CERTIFICATION I hereby attest that this report for the final drainage design for the Liberty Common Junior High was prepared by me or under my direct supervision, in accordance with the provisions of the Fort Collins Stormwater Criteria Manual. I understand that the City of Fort Collins does not and will not assume liability for drainage facilities designed by others. Lincoln J. Thomas, PE State of Colorado No. 42350 For and on behalf of Elevation Consulting Elevation Consulting 2 Final Drainage Report Liberty Common Junior High Fort Collins, Colorado TABLE OF CONTENTS 1 General Location and Existing Site Information........................................................ 4 2 Master Drainage Basin Information............................................................................ 7 3 Project Description...................................................................................................... 8 4 Drainage Design Criteria............................................................................................ 9 4.1 Regulations ......................................................................................................... 9 4.2 Four-Step Process ............................................................................................... 9 4.3 Hydrologic Criteria........................................................................................... 10 4.4 Hydraulic Criteria............................................................................................. 10 4.5 Low Impact Development................................................................................. 10 5 Variance Requests..................................................................................................... 11 6 Erosion Control......................................................................................................... 11 7 Conclusions............................................................................................................... 11 8 References................................................................................................................. 12 Appendices........................................................................................................................ 13 APPENDIX A—Hydrologic Computations APPENDIX B —Hydraulic Computations APPENDIX C —Referenced Information APPENDIX D—Drainage Map Elevation Consulting 3 Final Drainage Report Liberty Common Junior High Fort Collins, Colorado 1 General Location and Existing Site Information Liberty Common Junior High (Site) is located within Section 20, Township 7 North, Range 68 West of the 6th P.M. The following public roadways bound the Site, Sharp Point Drive to the northeast, March Court to the northwest and Canton Court to the southeast. Riverbend Court a former public right-of-way bisecting the Site has be vacated per Ordinance No. 004, 2025 and is now part of the Site. Liberty Common Elementary School is located to the northwest and southwest of the Site; 2601 Riverbend Court, 2609 Riverbend Court and 2600 Canton Court, existing commercial buildings, are also located to the southwest of the Site; Merganser Pond is located to the northeast of the Site; 2619 Canton Court, and existing multi-tenant building is located to the southeast of the Site, see vicinity map below. E PROSPECT RO Y� � PROJECT SITE MIA IPA A Y 'te VUNr Y MAP NOT TO SCME Figure 1-1 Vicinity Map The Site is located within the Cache La Poudre Master Basin per Figure 2.0-1 of the Fort Collins Stormwater Criteria Manual (FCSCM). Elevation Consulting 4 Final Drainage Report Liberty Common Junior High Fort Collins, Colorado There are no major drainageways through the Site. Per Flood Insurance Rate Map (FIRM) Map No. 08069CO984H and 08069C0992G, the Site is located in Zone X and not within a regulatory floodplain of Cache La Poudre River. There are no major irrigation facilities within or adjacent to the Site. Per the NRCS Soils Map in Appendix C, soils for this drainage study consist of Loveland clay loam, Caruso clay loam and Table Mountain loam. NRCS hydrologic soils group C has been used for the hydrology calculations for this drainage study. The Site is 4.05 acres, including the vacated right-of-way for Riverbend Court. Current improvements within the Site consist of 1825 Sharp Point Drive, an existing multi-tenant office building and parking lot; Riverbend Court, an existing cul-de-sac; and 1901 Sharp Point Drive, an existing multi-tenant office building and parking lot. A drainage area of 8.95 acres has been analyzed for the existing condition in this Drainage Report and is divided into 19 existing sub-basins. Basin EXl (0.73 ac) is located behind the 1825 Sharp Point Drive building. The basin consists of hardscape and landscaping. Runoff sheet flows to three area inlets within the parking lot and conveyed via (3) 12-inch storm sewer pipes under the building to an inlet (Design Point 3) on the front side of the building which outfalls to Merganser Pond. (Q2=1.8 cfs, Q100=7.3 cfs). In the event the inlets becomes plugged, emergency overflow path is at the southwest corner of the 1825 Sharp Point Drive building and into Basin EX3. Basin EX2 (0.44 ac) is located to the north of Basin EX1. The basin consists of the 1825 Sharp Point Drive building roof. Runoff is collected and routed through internal drains to the (3) 12-inch storm sewer pipes under the building and routed to an inlet (Design Point 3) on the front side of the building which outfalls to Merganser Pond. (Q2=1.2 cfs, Q 100=4.4 cfs). Basin EX3 (0.09 ac) is located to the west of the 1825 Sharp Point Drive building. The basin consists of hardscape and landscaping. Runoff sheet flows to a swale and drainage channel and is conveyed to the parking lot on the front side of the building, collected in an inlet (Design Point 3) and conveyed to Merganser Pond. (Q2=0.1 cfs, Q 100=0.4 cfs). Basin EX4 (0.54 ac) is located in front of the 1825 Sharp Point Drive building. The basin consists of hardscape and landscaping. Runoff sheet flows to an inlet (Design Point 3) and conveyed to Merganser Pond. (Q2=1.1 cfs, Q100=4.9 cfs). In the event the inlet becomes plugged, emergency overflow path is to the north and into Sharp Point Drive. Basin EX5 (0.58 ac) is located to the east of 1825 Sharp Point Drive. The basin consists of hardscape and landscaping. Runoff sheet flows to the vacated Riverbend Court curb and gutter and is conveyed to Sharp Point Drive right-of-way, collected by a sump curb inlet which outfalls to Merganser Pond. (Q2=1.0 cfs, Q100=4.9 cfs). Elevation Consulting 5 Final Drainage Report Liberty Common Junior High Fort Collins, Colorado Basin EX6 (0.28 ac) is located behind the 1901 Sharp Point Drive building. The basin consists of hardscape and landscaping. Runoff sheet flows to an area inlet (Design Point 5) within the parking lot and conveyed via a 12-inch storm sewer pipe under the building to an inlet (Design Point 8) on the front side of the building which outfalls to Merganser Pond. (Q2=0.7 cfs, Q 100=2.8 cfs). In the event the inlet becomes plugged, emergency overflow path is at the southeast corner of the 1901 Sharp Point Drive building and into Basin EX9. Basin EX7 (0.33 ac) is located behind the 1901 Sharp Point Drive building. The basin consists of hardscape and landscaping. Runoff sheet flows to an area inlet (Design Point 4) within the parking lot and conveyed via a 12-inch storm sewer pipe under the building to an inlet (Design Point 8) on the front side of the building which outfalls to Merganser Pond. (Q2=0.9 cfs, Q 100=3.3 cfs). In the event the inlet becomes plugged, emergency overflow path is at the southeast corner of the 1901 Sharp Point Drive building and into Basin EX9. Basin EX8 (0.23 ac) is located to the north of Basin EX6. The basin consists of a portion of the 1901 Sharp Point Drive building roof. Runoff is collected and routed through internal drains to an external drain on the east side of the building where a concrete drainage channel conveys flows to the parking lot on the front side of the building. Flows are collected via parking lot inlet (Design Point 8) and conveyed to Merganser Pond. (Q2=0.6 cfs, Q 100=2.3 cfs). Basin EX9 (0.04 ac) is located to the east of Basin EX8. The basin consists of hardscape and landscaping. Runoff sheet flows to drainage channels and is conveyed to the parking lot on the front side of the building. Flows are collected via parking lot inlet (Design Point 8) and conveyed to Merganser Pond. (Q2=0.0 cfs, Q100=0.1 cfs). Basin EX10 (0.56 ac) is located in front of the 1901 Sharp Point Drive building. The basin consists of hardscape and landscaping. Runoff sheet flows to an inlet(Design Point 8) and conveyed to Merganser Pond. (Q2=1.1 cfs, Q100=4.9 cfs). In the event the inlet becomes plugged, emergency overflow path is to the north and into Sharp Point Drive. Basin EX11 (0.23 ac) is located to the north of Basin EX7. The basin consists of a portion of the 1901 Sharp Point Drive building roof. Runoff is collected and routed through internal drains to an external drain on the west side of the building where it discharges to the vacated Riverbend Court curb and gutter and is conveyed to Sharp Point Drive right-of-way, collected by a sump curb inlet which outfalls to Merganser Pond. (Q2=0.6 cfs, Q 100=2.3 cfs). Basin OS1 (1.61 ac) is an offsite basin located to the south of Basin EX1 and consists of a portion of the Liberty Common Elementary school track and field. Land uses are hardscape, gravel and landscaping. Runoff is collected via trench drain or underdrains and routed to a junction structure in the eastern portion of the field where it discharges to the vacated Riverbend Court curb and gutter and is conveyed to Sharp Point Drive right- Elevation Consulting 6 Final Drainage Report Liberty Common Junior High Fort Collins, Colorado of-way, collected by a sump curb inlet which outfalls to Merganser Pond. (Q2=1.6 cfs, Q 100=6.9 cfs). Basin OS2 (1.45 ac) is an offsite basin located adjacent to OS1 and consists of the remaining portion of the Liberty Common Elementary school track and field. Land uses are hardscape, gravel and landscaping. Runoff is collected via trench drain or underdrains and routed to a junction structure in the eastern portion of the field where it discharges to the vacated Riverbend Court curb and gutter and is conveyed to Sharp Point Drive right-of-way, collected by a sump curb inlet which outfalls to Merganser Pond. (Q2=1.3 cfs, Q100=5.9 cfs). Basin OS3 (1.24 ac) is an offsite basin located to the south of Basin EX7. Land uses are industrial. Runoff sheet flows to a concrete drainage channel within the basin and is conveyed to the area inlet within Basin EX7 (Design Point 4) and onto Merganser Pond via the 1901 Sharp Point Drive storm sewer system. (Q2=3.0 cfs, Q100=11.2 cfs). Basin OS4 (0.54 ac) is an offsite basin located to the south of Basin EX6. Land uses are industrial. Runoff sheet flows to a concrete drainage channel within the basin and is conveyed to the area inlet within Basin EX6 (Design Point 5) and onto Merganser Pond via the 1901 Sharp Point Drive storm sewer system. (Q2=1.3 cfs, Q100=5.4 cfs). Basin OS5 (0.01 ac) is an offsite basin located to the east of Basin EX6. Land uses are landscape. Runoff sheet flows to the area inlet within Basin EX6 (Design Point 5) and onto Merganser Pond via the 1901 Sharp Point Drive storm sewer system. (Q2=0.0 cfs, Q 100=0.0 cfs). Basin OS6(0.01 ac) is an offsite basin located to the north of Basin EX10. Land uses are landscape. Runoff sheet flows to the area inlet within Basin EX10 (Design Point 8) and onto Merganser Pond via the 1901 Sharp Point Drive storm sewer system. (Q2=0.0 cfs, Q 100=0.0 cfs). Basin OS7 (0.02 ac) is an offsite basin located to the west of Basin EX1. Land uses are hardscape and landscape. Runoff sheet flows to the area inlet within Basin EX and onto Merganser Pond via the 1825 Sharp Point Drive storm sewer system. (Q2=0.0 cfs, Q 100=0.1 cfs). Basin OS8 (0.02 ac) is an offsite basin located to the north of Basin EX4. Land uses are landscape. Runoff sheet flows to the area inlet within Basin EX4 (Design Point 3) and onto Merganser Pond via the 1825 Sharp Point Drive storm sewer system. (Q2=0.0 cfs, Q 100=0.1 cfs). 2 Master Drainage Basin Information Elevation Consulting 7 Final Drainage Report Liberty Common Junior High Fort Collins, Colorado The Site is located within the Cache La Poudre River watershed. Per the City's website, the Master Plan update for the watershed is currently underway. Site is not identified on the Cache La Poudre River Problem Identification Map or Flooding Solution Map. 3 Project Description The majority of the existing improvements are to remain. Construction includes minor parking lot improvements, utility services, landscaping and 17,240 s.£ building addition between 1825 and 1901 Sharp Point Drive buildings. The proposed construction activities associated with this report are grading, paving, utility, storm drainage improvements and vertical construction with the total area of these proposed grading activities being 1.33 acres. The existing grades are flat to steep ranging from less than 1%to 24%. The overall drainage area of 8.95 acres did not change with the post development analysis, 2 new sub-basins were created as well as modifications to 8 existing sub-basins. Basin C2 ( 0.90 ac) is located in between 1825 and 1901 Sharp Point Drive buildings. Land uses are rooftop, landscape and hardscape. Surface runoff will be conveyed overland to Rain Garden #1 and routed through the Site storm sewer system to Merganser Pond. Building runoff will be piped via the Site storm sewer system to the Rain Garden #1 and routed through the Site storm sewer system to Merganser Pond. (Q2=1.6 cfs, Q100=6.9 cfs). Basin C3 ( 0.07 ac) is located to the north of Basin C2. Land uses are landscape and hardscape. Runoff sheet flows to Sharp Point Drive right-of-way, collected by a sump curb inlet which outfalls to Merganser Pond. (Q2=0.0 cfs, Q 100=0.2 cfs). Basin EX1-A (0.96 ac) Land uses are not being changed, but basin area and composite imperviousness are being modified with Site improvements. Runoff will continue to sheet flow to three existing area inlets within the parking lot and conveyed via (3) 12- inch storm sewer pipes under the building to an inlet (Design Point 3) on the front side of the building which outfalls to Merganser Pond. (Q2=2.2 cfs, Q 100=9.6 cfs). Emergency overflow path will not change and continue to be into Basin EX3. Basin EX2-A (0.44 ac) is located to the north of Basin EX1-A. The basin area and land use have not been changed. Runoff will now be collected and routed through internal drains to (2) new external roof drains on the March Court side of the building. Runoff sheet flows to a swale and drainage channel within Basin EX-3 and is conveyed to the parking lot on the front side of the building, collected in the existing inlet (Design Point 3) and conveyed to Merganser Pond. (Q2=1.2 cfs, Q100=4.4 cfs). Basin EX4-A (0.48 ac) Land uses are not being changed, but basin area and composite imperviousness are being modified with Site improvements. Runoff will continue to sheet flow to an existing inlet within the parking lot (Design Point 3) and be conveyed to Elevation Consulting 8 Final Drainage Report Liberty Common Junior High Fort Collins, Colorado Merganser Pond. (Q2=1.0 cfs, Q100=4.5 cfs). Emergency overflow path will not change and continue to be into Sharp Point Drive. Basin EX7-A (0.33 ac) Site improvements do not modify the Basin area or land uses, but there is a change in composite imperviousness. Runoff will continue to sheet flow to an area inlet (Design Point 4) within the parking lot and conveyed via a 12-inch storm sewer pipe under the building to an inlet (Design Point 8) on the north side of the building which outfalls to Merganser Pond. (Q2=0.8 cfs, Q 100=3.3 cfs). Emergency overflow path will not change and continue to be into Basin EX9. Basin EX10-A (0.23 ac) ) Land uses are not being changed, but basin area and composite imperviousness are being modified with Site improvements. Runoff will now be conveyed overland to Rain Garden #2 and routed through the Site storm sewer system to Merganser Pond. (Q2=0.1 cfs, Q100=1.0 cfs). Emergency overflow path will not change and continue to be into Sharp Point Drive. Basin OS1-A (1.61 ac) Land uses, basin area and composite imperviousness are not being modified with Site improvements. Runoff will now discharge to the March Court curb and gutter, conveyed to Sharp Point Drive right-of-way, collected by a sump curb inlet which outfalls to Merganser Pond. (Q2=1.6 cfs, Q100=6.9 cfs). Basin OS2-A (1.44 ac)Land uses, basin area and composite imperviousness are not being modified with Site improvements. Runoff will now discharge to the March Court curb and gutter, conveyed to Sharp Point Drive right-of-way, collected by a sump curb inlet which outfalls to Merganser Pond. (Q2=1.3 cfs, Q 100=5.9 cfs). Basin OS7-A (0.02 ac) Land uses, basin area and composite imperviousness are not being modified with Site improvements. Runoff will now discharge to the March Court curb and gutter, conveyed to Sharp Point Drive right-of-way, collected by a sump curb inlet which outfalls to Merganser Pond. (Q2=0.0 cfs, Q 100=0.1 cfs). 4 Drainage Design Criteria 4.1 Regulations This drainage report was prepared in accordance with the Fort Collins Stormwater Citeria Manual (FCSCM). 4.2 Four-Step Process Site complies with the City's four step process to minimize adverse impacts of urbanization. Step 1 — Employing runoff reduction practices; new Site imperviousness, 73%, will not exceed existing conditions, 80%, therefore reducing runoff volume. Step 2 — Implementing best management practice (BMPs) that provide a water quality capture volume with slow release and/or infiltration; new rain gardens will be constructed as part of the project to provide WQCV for modified areas of the Site. Step 3 — Stabilizing streams; there are no drainageways on or adjacent to the Site, therefore Step 3 is not Elevation Consulting 9 Final Drainage Report Liberty Common Junior High Fort Collins, Colorado applicable to this project. Step 4 — Implementing site specific and other source control BMPs; Site use of a school facility will minimize risk for illicit discharges from material storage, vehicle maintenance and manufacturing as these site activities are not generally associated with a school facility. Good housekeeping practices will be implemented to control the potential for illicit discharges from the Site. 4.3 Hydrologic Criteria The minor storm was calculated for the 2-year recurrence interval and the major storm was calculated at the 100-year recurrence interval. The Rational Method was used for determining peak runoff rate. Runoff coefficients were calculated for each sub basin using values from the FCSCM Tables 3.2-1, 3.2-2 and 3.2-3. The developed time of concentration for the basins were calculated using FCSCM Equation 5-3. The initial overland flow time was calculated using FCSCM Equation 3.3- 2. Channelized flow time was calculated using Manning's Equation for velocity and FCSCM Equation 5-5. The maximum total time of concentration for the most upstream basins were calculated using FCSCM Equation 3.3-5. The project design rainfall intensities were determined using FCSCM Table 3.4-1. Rain Garden Water Quality Capture Volume (WQCV) was calculated using FCSCM Equation 7-1 and 7-2 with a drain time of 12 hours. Additional 20% storage volume listed in equation 7-2 was removed for Low Impact Development(LID) systems. Complete calculations are included in Appendix A. 4.4 Hydraulic Criteria All new Site storm sewers will be private and sized to convey the 100-year storm event. Inlets were sized to capture runoff using the software from Mile High Flood District (MHFD). StormCAD and Flowmaster, software programs developed by Bentley Systems, were used to determine storm sewer hydraulic gradelines, velocities and capacities as well as roadway Pipe hydraulic calculations show the existing 1825 Sharp Point storm system has capacity for the increased runoff from basin EX1-A, pipe HGL and EGL are still contained within the pipes. Open channel flow calculations for March Court show the street has conveyance capacity for the redirected runoff from the Liberty Common Elementary school track and field without overtopping curb. 4.5 Low Impact Development Proposed improvements will modify 1.33 acres of the Site. 917 cubic feet of WQCV is needed for this disturbed area in order to meet City's Low Impact Development requirements. Rain Gardens 1 & 2 will provide 1,292 cubic feet of WQCV, therefore exceeding the minimum requirements. Refer to Stormwater Quality Exhibit in Appendix A. Elevation Consulting 10 Final Drainage Report Liberty Common Junior High Fort Collins, Colorado 5 Variance Requests No variances associated with drainage are being requested. 6 Erosion Control Erosion Control Plan and Erosion Control Report in compliance with the Fort Collins Stormwater Criteria Manual will be submitted as part of the permitting for this project. 7 Conclusions The Site is designed in compliance with the Fort Collins Stormwater Criteria Manual. Site runoff to the existing 1901 Sharp Point Drive storm sewer system has been reduced. Site runoff to the existing 1825 Sharp Point Drive storm sewer system has been slightly increased, but existing system has capacity for the increased flows. Stormwater runoff being conveyed underneath either of the existing buildings has not been increased with the proposed improvements. Total runoff from the Site to Merganser Pond has been reduced per Design Flow Comparison below, therefore proposed Site improvements should not negatively impact downstream properties. Design Flow Comparison Table Pre Development Post Development Design Point Q2 (cfs) Q100 (cfs) Design Q2 (cfs) Q100 (cfs) Point 3 3.8 17.1 3 4.2 18.8 8 7.1 28.0 8 7.1 27.3 9 4.2 18.2 9 3.0 13.0 TOTAL 15.1 63.3 14.3 59.1 Elevation Consulting 11 Final Drainage Report Liberty Common Junior High Fort Collins, Colorado 8 References 1 Fort Collins Stormwater Criteria Manual; City of Fort Collins; December 2018. 2 Mile High Flood District Storm Drainage Criteria Manual Volumes 1, 2 & 3; Mile High Flood District;November 2010. Elevation Consulting 12 Final Drainage Report Liberty Common Junior High Fort Collins, Colorado Appendices APPENDIX A—Hydrologic Analyses APPENDIX B —Hydraulic Analyses APPENDIX C—Referenced Information APPENDIX D—Drainage Map Elevation Consulting 13 Final Drainage Report Liberty Common Junior High Fort Collins, Colorado APPENDIX A HYDROLOGIC COMPUTATIONS Elevation Consulting 14 Pre-Development C Value Calculations Liberty Common Junior High Fort Collins,Colorado Global Parameters requency Adjustment Factors(C F) Land Use %Impervious' CZ 2-YR 1.00 Asphalt,Concrete 100% 0.95 100-YR 1.25 Rooftop 90% 0.95 Gravel 40% 0.50 Lawns,Clayey Soil,Flat Slope<2% 2% 0.20 Lawns,Clayey Soil,Avg Slope 2-7% 2% 0.25 Lawns,Clayey Soil,Steep Slope>7% 2% 0.35 Industrial Land Use 90% 0.95 Land Use Area per Sub-Basin C'CF(1.00 MAX) Lawns,Clayey Soil,Flat Lawns,Clayey Soil, Lawns,Clayey Soil, Composite Composite Subbasin Total Area(acres) Asphalt,Concrete Rooftop Gravel Industrial Land Use %Check a Slope<2% Avg Slope 2-7% Steep Slope>7% Imperviousness C Coefficient 2-YR 100-YR Area(acres) % Area(acres) % Area(acres) % Area(acres) % Area(acres % Area(acres % Area(acres) EX1 0.73 0.63 86.3% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.10 13.7% 0.00 0.0% 0 0.0% 100.00% 87% 0.85 0.85 1.00 EX2 0.44 0.00 0.0% 0.44 100.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0 0.0% 100.00% 90% 0.95 0.95 1.00 EX3 0.09 0.01 11.1% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.08 88.9% 0.00 0.0% 0.00 0.0% 100.00% 13% 0.33 0.33 0.41 EX4 0,54 0.37 68.5% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.17 31.5% 0.00 0.0% 0.00 0.0% 100,00% 69% 0.73 0.73 0.91 EX5 0.58 0.45 77.6% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.13 22.4% 0.00 0.0% 0.00 0.0% 100.00% 78% 0.79 0.79 0.99 EX6 0.28 0.27 96.4% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.01 3.6% 0.00 0.0% 0.00 0.0% 100.00% 97% 0.93 0.93 1.00 EX7 0.33 0.32 97.0% 1 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.01 3.0% 0.00 0.0% 0.00 0.0% 100.00% 97% 0.93 0.93 1.00 EX8 0.23 0.00 0.0% 0.23 100.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 100,00% 90% 0.95 0.95 1.00 EX9 0.04 0.00 0.0% 0.00 0.0% 0.00 1 0.0% 0.00 1 0.0% 0.04 1 100.0% 0.00 1 0.0% 0.00 1 0.0% 100.00% 2% 0.25 0.25 0.31 EX10 0.56 0.36 64.3% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.20 35.7% 0.00 0.0% 0.00 0.0% 100.00% 65% 0.70 0.70 0.88 EX11 0.23 0.00 0.0% 0.23 100.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 100,00% 90% 0.95 0.95 1.00 Subtotal 4.05 2.41 59.5% 0.90 22.2% 0.00 0.0% 0.00 0.0% 0.74 18.3% 0.00 0.0% 0.00 0.0% 100.00% 80% 0.82 0.82 1.00 OS1 1.61 0.54 33.5% 0.00 0.0% 0.26 16.1% 0.81 50.3% 0.00 0.0% 0.00 0.0% 0.00 0.0% 100,00% 41% 0.50 0.50 0.63 OS2 1.45 0.46 31.7% 0.00 0.0% 0.18 12.4% 0.81 55.9% 0.00 0.0% 0.00 0.0% 0.00 0.0% 100.00% 38% 1 0.48 0.48 1 0.59 OS3 1.24 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 1.24 100.0% 100.00% 90% 0.95 0.95 1.00 OS4 0.54 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.54 100.0% 100.00% 90% 0.95 0.95 1.00 OS5 0.01 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.01 100.0% 0.00 0.0% 0.00 0.0% 100,00% 2% 0.25 0.25 0.31 OS6 0.01 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.01 100.0% 1 0.00 0.0% 0.00 1 0.0% 100.00% 2% 0.25 0.25 0.31 OS7 0.02 0.01 50.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.01 50.0% 0.00 0.0% 0.00 0.0% 100.00% 51% 0.60 0.60 0.75 OS8 0.02 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.02 100.0% 0.00 0.0% 0.06 0.0% 100,00% 2% 0.25 0.25 0.31 Subotal 4.90 1.01 20.61/1 0.00 0.0% 0.44 9.0% 1.62 33.1% 0.05 1.0% 0.00 0.0% 1.78 1 36.3% 100.00% 58% 0.65 0.65 0.82 Total 8.95 3.42 38.2% 0.90 10.1% 0.44 4.9% 1.62 18.1% 0.79 8.8% 0.00 0.0% 1.78 19.9% 100.00% 681/c 0.73 0.73 0.91 1.From Tables 4.1-2 and 4.1-3 in the Fort Collins Stormwater Criteria Manual 2. From Tables 3.2-1 and 3.2-2 in the Fort Collins Stormwater Criteria Manual 3.From Table 3.2-3 in the Fort Collins Stormwater Criteria Manual 4. From Equation 5-2 in the Fort Collins Stormwater Criteria Manual STANDARD FORM SF-2 TIME OF CONCENTRATION Development: Liberty Common Junior High Calculated By: UT Date: 2/22/2025 Subbasin Data Time of Concentration,T. Initial/Overland Time(t i)s Travel Time(tt)4 Concentration(T c)s T.Checks Final T, 5 x o N K} X o y o o N C $ @ C fill > Il o u o C O rn Q U.�.., U.r.. J v !n - - J U) F- ♦-J FV.N... F`. F + IL v iE.r... ft % min. min. ft % fps Tc min min min min EX1 0.73 0.85 1.00 110 2.7% 3.5 1.4 110 3.5 m114 min10.6 5I0 5I0 EX2 0.44 0.95 1.00 5.0 5.0 EX3 0.09 0.33 0.41 13 10.0% 2.4 2.2 215 1.4% 1.3 2.8 228 5.2 4.91 11.3 5.2 5.0 EX4 0.54 0.73 0.91 10 10.0% 1.0 0.5 1 265 1.1% 1 1.1 3.9 275 4.9 4.4 11.5 5.0 5.0 EX5 0.58 0.79 0.99 42 3.0% 2.6 0.9 287 0.4% 0.7 6.9 329 9.5 Z9 11.8 9.5 7.9 EX6 0.28 0.93 1.00 73 2.8% 2.0 1.1 47 1.3% 1.2 0.6 120 2.6 1.8 10.7 5.0 5.0 EX7 0.33 0.93 1.00 61 4.1% 1.6 0.9 59 1.6% 1.4 0.7 120 2.3 1.6 10.7 5.0 5.0 EX8 0.23 0.95 1.00 5.0 5.0 EX9 0.04 0.25 0.31 5.0 5.0 EX10 0.56 0.70 0.88 28 6.6% 2.1 1.2 102 2.3% 1.7 1.0 130 3.1 22 10.7 5.0 5.0 EX11 0.23 0.95 1.00 5.0 5.0 OS1 1.61 0.50 0.63 88 1.0% 10.5 8.3 535 0.5% 0.2 44.3 623 54.8 52.61 13.5 13.5 1 13.5 OS2 1 1.45 0.48 0.59 95 1 1.0% 11.4 9.2 535 0.5% 0.2 44.3 630 55.7 53.5 13.5 13.5 13.5 OS3 1.24 0.95 1.00 22 2.0% 1.0 0.7 387 1.0% 1.1 5.9 409 7.0 6.6 12.3 7.0 6.6 OS4 0.54 0.95 1.00 22 2.0% 1.0 0.7 391 1.0% 1.1 6.0 413 7.0 6.7 12.3 7.0 6.7 OS5 0.01 0.25 0.31 5.0 5.0 OS6 0.01 0.25 0.31 5.0 5.0 OS7 0.02 0.60 0.75 5.0 5.0 OS8 0.02 025 0.31 5.0 5.0 Notes: 1. Flows calculated using the rational method,based on the methods provided in Chapter 5(Hydrology Standards)of the Fort Collins Stormwater Criteria Manual 2.Ti=[1.87(1.1-CxCr)Lo`]/S1" C=Runoff Coefficient Cf=Frequency Adjustment Factor L=Length of Overland Flow,feet S=Slope,percent Roughness Hydraulic Radius,R 3. V=(1.49/n)R''�S Coeffiicients7 V=velocity ��Pewious Use n 4'pan 0.04 assuming full pan field (4)4-inch pipes n=Roughness Coefficient ce 0.25 underdrain 0.33 assuming full mpervious R=Hydraulic Radius,feet Surface 0.016 S=Longitudinal Slope,feettfeet 4.Tt=U(Vx60) 5.T.=Ti+Tt Tc is the lesser of the values of equations 5.and 6.Tc=(U180)+10 6.,min Tc=5.0 minutes 7.From Table 4.1-1 in the Fort Collins Stormwater Criteria Manual Standard Form SF-3 Storm Drainage System Design (Rational Method Procedure) Calculated By: LJT Job#: 2024020 Date: 2/22/2025 Project: Liberty Common Junior High Design Storm: 2-Year Storm DIRECT RUNOFF TOTAL RUNOFF STREET PIPE TRAVEL TIME STREET DESIGN POINT Area Area CoeH Tc C`A I Q Tc Sum CAA I Q Sloe Street Q Design Q Sloe PIPE L VEL Tt Q add'I Q tot Design ac C min ac cfs min ac in/hr cfs % cfs cfs % SIZE ft ft/sec min 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 OS1 1.61 0.50 13.5 0.81 1.95 1.6 OS2 1.45 0.48 13.5 0.69 1.95 1.3 1 13.5 1.49 1.95 2.9 OS7 0.02 0.60 5.0 0.01 2.85 0.0 EX1 0.73 0.85 5.0 0.62 2.85 1.8 EX2 0.44 0.95 5.0 0.42 2.85 1.2 2 5.0 1.05 2.61 2.7 EX3 0.09 0.33 5.2 0.03 2.81 0.1 EX4 0.54 0.73 5.0 0.39 2.85 1.1 OS8 0.02 0.25 5.0 0.01 2.85 0.0 3 1 5.21 1.48 2.59 1 3.8 OS3 1.24 0.95 7.0 1.18 2.52 3.0 EX7 0.33 0.93 5.0 0.31 2.85 0.9 4 7.0 1.48 2.45 3.6 OS4 0.54 0.95 7.0 0.51 2.49 1.3 OS5 0.01 0.25 5.0 0.00 2.85 0.0 EX6 0.28 0.93 5.0 0.26 2.85 0.7 5 7.0 0.77 2.45 1.9 6 7.0 2.26 2.45 5.5 EX8 0.23 0.95 5.0 0.22 2.85 0.6 EX9 0.04 0.25 5.0 0.01 2.85 0.0 7 5.0 0.23 2.61 0.6 EX10 0.56 0.70 5.0 0.39 2.85 1.1 OS6 0.01 0.25 5.0 0.00 2.85 0.0 8 7.0 2.88 2.45 7.1 EX5 0.58 0.79 9.5 0.46 2.25 1.0 EX11 0.23 0.95 5.0 0.22 2.85 0.6 9 13.5 2.17 1.95 4.2 Standard Form SF-3 Storm Drainage System Design (Rational Method Procedure) Calculated By: LJT Job#: 2024020 Date: 2/22/2025 Project: Liberty Common Junior High Design Storm: 100-Year Storm DIRECT RUNOFF TOTAL RUNOFF STREET PIPE TRAVEL TIME STREET DESIGN POINT Area Area CoeH Tc C`A I Q Tc Sum CAA I Q Sloe Street Q Design Q Sloe PIPE L VEL Tt Q add'I Q tot Design ac C min ac cfs min ac in/hr cfs % cfs cfs % SIZE ft ft/sec min 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 OS1 1.61 0.63 13.5 1.01 6.82 6.9 OS2 1.45 0.59 13.5 0.86 6.82 5.9 1 13.5 1.87 6.82 12.7 OS7 0.02 0.75 5.0 0.02 9.95 0.1 EX1 0.73 1.00 5.0 0.73 9.95 7.3 EX2 0.44 1.00 5.0 0.44 9.95 4.4 2 5.0 1.19 9.95 11.8 EX3 0.09 0.41 5.0 0.04 9.95 0.4 EX4 0.54 0.91 5.0 0.49 9.95 4.9 OS8 0.02 0.31 5.0 0.01 9.95 0.1 3 1 5.01 1.72 9.95 1 17.1 OS3 1.24 1.00 6.6 1.24 8.99 11.2 EX7 0.33 1.00 5.0 0.33 9.95 3.3 4 6.6 1.57 8.99 14.1 OS4 0.54 1.00 6.7 0.54 9.95 5.4 OS5 0.01 0.31 5.0 0.00 9.95 0.0 EX6 0.28 1.00 5.0 0.28 9.95 2.8 5 6.7 0.82 9.95 8.2 6 6.7 2.39 8.96 21.5 EX8 0.23 1.00 5.0 0.23 9.95 2.3 EX9 0.04 0.31 5.0 0.01 9.95 0.1 7 5.0 0.24 9.95 2.4 EX10 0.56 0.88 5.0 0.49 9.95 4.9 OS6 0.01 0.31 5.0 0.00 9.95 0.0 8 6.7 3.13 8.96 28.0 EX5 0.58 0.99 7.9 0.58 8.44 4.9 EX11 0.23 1.00 5.0 0.23 9.95 2.3 9 13.5 2.67 6.82 18.2 Post-Development C Value Calculations Liberty Common Junior High Fort Collins,Colorado Global Parameters requency Adjustment Factors(C F) Land Use %Impervious' CZ 2-YR 1.00 Asphalt,Concrete 100% 0.95 100-YR 1.25 Rooftop 90% 0.95 Gravel 40% 0.50 Lawns,Clayey Soil,Flat Slope<2% 2% 0.20 Lawns,Clayey Soil,Avg Slope 2-7% 2% 0.25 Lawns,Clayey Soil,Steep Slope>7% 2% 0.35 Industrial Land Use 90% 0.95 Land Use Area per Sub-Basin C'CF(1.00 MAX) Lawns,Clayey Soil,Flat Lawns,Clayey Soil, Lawns,Clayey Soil, Composite Composite Subbasin Total Area(acres) Asphalt,Concrete Rooftop Gravel Industrial Land Use %Check a Slope<2% Avg Slope 2-7% Steep Slope>7% Imperviousness C Coefficient 2-YR 100-YR Area(acres) % Area(acres) % Area(acres) % Area(acres) % Area(acres % Area(acres % Area(acres) C2 0.9 0.05 5.6% 0.62 68.9% 0.00 0.0% 0.00 0.0% 0.23 25.6% 0.00 0.0% 0.00 0.0% 100.00% 68% 0.77 0.77 0.96 C3 0.07 0 0.0% 0 0.0% 0.00 0.0% 0.00 0.0% 0.07 100.0% 0.00 0.0% 0.00 0.0% 100.00% 2% 0.25 0.25 0.31 EX1-A 0.96 0.76 79.2% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.20 20.8% 0.00 0.0% 0.00 0.0% 100.00% 80% 0.80 0.80 1.00 EX2-A 0.44 0.00 0.0% 0.44 100.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 100,00% 90% 0.95 0.95 1.00 EX3 0.09 0.01 11.1% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.08 88.9% 0.00 0.0% 0.00 0.0% 100.00% 13% 0.33 0.33 0.41 EX4-A 0.48 0.34 70.8% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.14 29.2% 0.00 0.0% 0.00 0.0% 100.00% 71% 0.75 0.75 0.93 EX6 0.28 0.27 96.4% 1 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.01 3.6% 0.00 0.0% 0.00 0.0% 100.00% 97% 0.93 0.93 1.00 EX7-A 0.33 0.30 90.9% 0.00 0.0% 0.00 0.0"/ 0.00 0.0% 0.03 9.1% 0.00 0.0% 0.00 0.0% 100,00% 91% 0.89 0.89 1.00 EX8 0.23 0.00 0.0% 0.23 100.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 100.00% 90% 0.95 0.95 1.00 EX9 0.04 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.04 100.0% 0.00 0.0% 0.00 0.0% 100.00% 2% 0.25 0.25 0.31 EX10-A 0.23 0.03 13.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.20 87.0% 0.00 0.0% 0.00 0.0% 100,00% 15% 0.34 0.34 0.43 Subtotal 4.05 1.76 43.5% 1.29 31.9% 0.00 0.0% 0.00 0.0% 1.00 24.70/c 0.00 0.0% 0.00 0.0% 100.001/1 731/c 0.78 0.78 0.97 OS1-A 1.61 0.54 33.5% 0.00 0.0% 0.26 16.1% 0.81 50.3% 0.00 0.0% 0.00 0.0% 0.00 0.0% 100,00/ 41% 0.50 0.50 0.63 OS2-A 1.45 0.46 31.7% 0.00 0.0% 0.18 12.4% 0.81 55.9% 0.00 0.0% 0.00 0.0% 0.00 0.0% 100.00% 38% 0.48 0.48 0.59 OS3 1.24 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 1.24 100.0% 100.00% 90% 0.95 0.95 1.00 OS4 0.54 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.54 100.0% 100.00% 90% 0.95 0.95 1.00 OS5 0.01 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.01 100.0% 0.00 0.0% 0.00 0.0% 100,00/ 2% 0.25 0.25 0.31 OS6 0.01 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.01 100.0% 0.00 0.0% 0.00 0.0% 100.00% 2% 0.25 0.25 0.31 OS7-A 0.02 0.01 50.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.01 50.0% 0.00 0.0% 0.00 0.0% 100.00% 51% 0.60 0.60 0.75 OS8 0.02 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.00 0.0% 0.02 100.0% 0.00 0.0% 0.00 0.0% 100.00% 2% 0.25 0.25 0.31 Subotal 4.90 1.01 20.6% 0.00 0.0% 0.44 9.0% 1.62 33.1% 0.05 1.0% 0.00 0.0% 1.78 1 36.3% 100.00% 58% 0.65 0.65 0.82 Total 8.95 2.77 30.9% 1.29 14.4% 0.44 4.9% 1.62 18.1% 1.05 11.7% 0.00 0.0% 1.78 19.9% 100.00% 64% 0.71 0.71 0.89 1.From Tables 4.1-2 and 4.1-3 in the Fort Collins Stormwater Criteria Manual 2. From Tables 3.2-1 and 3.2-2 in the Fort Collins Stormwater Criteria Manual 3.From Table 3.2-3 in the Fort Collins Stormwater Criteria Manual 4. From Equation 5-2 in the Fort Collins Stormwater Criteria Manual STANDARD FORM SF-2 TIME OF CONCENTRATION Development: Liberty Common Junior High Calculated By: LJT Date: 3/6/2025 Subbasin Data Time of Concentration,T. Initial/Overland Time(ti)z Travel Time(t()q Concentration(Tc)s T.Checks Final T, m } $ E } x +,� + of m U> Z. mo 0 0yy1 x xo o c c o N 4 U.N... U.r.. J.S co - - J (n � F- F-J F,.- F Z F�.J....+ acres It % min. min. ft % fps Tc min C2 0.90 0.77 0.96 186 1.0% 8.4 3.5 44 4A% 0.6 1.2 230 ml9 6 mm4 7 min 11.3 916 5.0 C3 0.07 0.25 0.31 5.0 5.0 EX1-A 0.96 0.80 1.00 71 2.3% 3.5 1.2 166 1.0% 1.1 2.5 237 6.1 3.71 11.3 6.1 5.0 EX2-A 1 0.44 0.95 1 1.00 1 5.0 5.0 EX3 0.09 0.33 0.41 13 10.0% 2.4 2.2 215 1.41/6 1.3 2.8 228 5.2 4.9 11.3 5.2 5.0 EX4-A 0.48 0.75 0.93 10 10.0% 1.0 0.5 265 1.1% 1.1 3.9 275 4.8 4.3 11.5 5.0 5.0 EX6 0.28 0.93 1.00 73 2.8% 2.0 1.1 47 1.3% 1.2 0.6 120 2.6 1.8 10.7 5.0 5.0 EX7-A 0.33 0.89 1.00 61 4.1% 1.9 0.9 59 1.6% 1.4 0.7 120 2.7 1.6 10.7 5.0 5.0 EX8 0.23 0.95 1.00 5.0 5.0 EX9 0.04 0.25 0.31 5.0 5.0 EX10-A 0.23 0.34 0.43 85 2.0% 10.4 9.2 85 1 10.4 9.2 10.5 10.4 9.2 OS1-A 1.61 0.50 0.63 88 1 1.0% 10.5 1 8.3 535 0.5% 0.2 44.3 623 54.8 52.61 13.5 13.5 1 13.5 OS2-A 1 1.45 0.48 1 0.59 95 1.0% 11.4 9.2 535 0.5% 0.2 44.3 630 55.7 53.5 13.5 13.5 13.5 OS3 1.24 0.95 1.00 22 2.0% 1.0 0.7 387 1.0% 1.1 5.9 409 7.0 6.6 12.3 7.0 6.6 OS4 0.54 0.95 1.00 22 2.0% 1.0 0.7 391 1.0% 1.1 6.0 413 7.0 6.7 12.3 7.0 6.7 OS5 0.01 0.25 0.31 5.0 5.0 OS6 0.01 0.25 0.31 5.0 5.0 OS7-A 0.02 0.60 0.75 5.0 5.0 OS8 0.02 0.25 0.31 1 5.0 5.0 Notes: 1. Flows tabulated using the rational method,based on the methods provided in Chapter 5(Hydrology Standards)of the Fort Collins Stormwater Criteria Manual 2.T;=[1.87(1.1-CxCr)L05J/V C=Runoff Coefficient CrFrequency Adjustment Factor L=Length of Overland Flow,feet S=Slope,percent as oug news Hydraulic Radius,R 3.V=(1.49/n)R S Coefficients? V=velocity Land Use in 4'pan 0.04 assuming full pan Pervious field (4)4-inch pipes n=Roughness Coefficient Surface 0.25 underdrain 0.33 assuming full mpervious R=Hydraulic Radius,feet Surface 0.016 S=Longitudinal Slope,feet/feet 4.Tr=L/(VX60) 5.T.=Ti+Tr Tc is the lesser of the values of equations 5.and 6.Tc=(L/180)+10 6.,min Tc=5.0 minutes 7.From Table 4.1-1 in the Fort Collins Stormvrater Criteria Manual Standard Form SF-3 Storm Drainage System Design (Rational Method Procedure) Calculated By: LJT Job#: 2024020 Date: 3/6/2025 Project: Liberty Common Junior High Design Storm: 2-Year Storm DIRECT RUNOFF TOTAL RUNOFF STREET PIPE TRAVEL TIME STREET DESIGN POINT Area Area CoeH Tc C`A I Q Tc Sum CAA I Q Sloe Street Q Design Q Sloe PIPE L VEL Tt Q add'I Q tot Design ac C min ac cfs min ac in/hr cfs % cfs cfs % SIZE ft ft/sec min 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 OS1-A 1.61 0.50 13.5 0.81 1.95 1.6 OS2-A 1.45 0.48 13.5 0.69 1.95 1.3 OS7-A 0.02 0.60 5.0 0.01 2.85 0.0 1 13.5 1.51 1.95 2.9 EX1-A 0.96 0.80 6.1 0.77 2.66 2.1 EX2-A 0.44 0.95 5.0 0.42 2.85 1.2 EX3 0.09 0.33 5.2 0.03 2.81 0.1 EX4-A 0.48 0.75 5.0 0.36 2.85 1.0 OS8 0.02 0.25 5.0 0.01 2.85 0.0 3 6.1 1.58 2.66 4.2 OS3 1.24 0.95 7.0 1.18 2.52 3.0 EX7-A 0.33 0.89 5.0 0.29 2.85 0.8 4 7.0 1.47 2.52 3.7 OS4 0.54 0.95 7.0 0.51 2.52 1.3 OS5 0.01 0.25 5.0 0.00 2.85 0.0 EX6 0.28 0.93 5.0 0.26 2.85 0.7 5 7.0 0.77 2.52 2.0 6 7.0 2.25 2.52 5.7 EX8 0.23 0.95 5.0 0.22 2.85 0.6 EX9 0.04 0.25 5.0 0.01 2.85 0.0 7 5.0 0.23 2.85 0.7 C2 0.90 0.77 9.6 0.69 2.24 1.6 EX10-A 0.23 0.34 10.4 0.08 2.18 0.2 OS6 0.01 0.25 5.0 0.00 2.85 0.0 8 10.4 3.25 2.18 7.1 C3 0.07 0.25 5.0 0.02 2.85 0.0 9 13.5 1.52 1.95 3.0 Standard Form SF-3 Storm Drainage System Design (Rational Method Procedure) Calculated By: LJT Job#: 2024020 Date: 3/6/2025 Project: Liberty Common Junior High Design Storm: 100-Year Storm DIRECT RUNOFF TOTAL RUNOFF STREET PIPE TRAVEL TIME STREET DESIGN POINT Area Area CoeH Tc C`A I Q Tc Sum CAA I Q Sloe Street Q Design Q Sloe PIPE L VEL Tt Q add'I Q tot Design ac C min ac cfs min ac in/hr cfs % cfs cfs % SIZE ft ft/sec min 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 OS1-A 1.61 0.63 13.5 1.01 6.82 6.9 OS2-A 1.45 0.59 13.5 0.86 6.82 5.9 OS7-A 0.02 0.75 5.0 0.02 9.95 0.1 1 13.5 1.88 6.82 12.8 EX 1-A 0.96 1.00 5.0 0.96 9.95 9.6 EX2-A 0.44 1.00 5.0 0.44 9.95 4.4 EX3 0.09 0.41 5.0 0.04 9.95 0.4 EX4-A 0.48 0.93 5.0 0.45 9.95 4.5 OS8 0.02 0.31 5.0 0.01 9.95 0.1 3 5.01 1.89 9.95 18.8 OS3 1.24 1.00 6.6 1.24 8.99 11.2 EX7-A 0.33 1.00 5.0 0.33 9.95 3.3 4 6.6 1.57 8.99 14.1 OS4 0.54 1.00 6.7 0.54 8.96 4.8 OS5 0.01 0.31 5.0 0.00 9.95 0.0 EX6 0.28 1.00 5.0 0.28 9.95 2.8 5 6.7 0.82 8.96 7.4 6 6.7 2.39 8.96 21.5 EX8 0.23 1.00 5.0 0.23 9.95 2.3 EX9 0.04 0.31 5.0 0.01 9.95 0.1 7 5.0 0.24 9.95 2.4 C2 0.90 0.77 5.0 0.69 9.95 6.9 EX10-A 0.23 0.43 9.2 0.10 7.96 0.8 OS6 0.01 0.31 5.0 0.00 9.95 0.0 8 9.2 3.43 7.96 27.3 C3 0.07 0.31 5.0 0.02 9.95 0.2 9 13.5 1.90 6.82 13.0 r m TRIBUTARY AREA TO RAIN GARDEN NO. 1 = 0.90 4896 SHARP POINT DRIVE ACRES m RAIN GARDEN NO. 1 \ Lu n L - - - _ _ 1' DEPTH _ 1 O cn - 4896 - ems- - s° I . . . - RAIN GARDEN N0. 2 w 04 04 D A896 1' DEPTH - I '' I RAIN GARDEN OUTFALL N PIPES o \ _ / -73 _ \ J P J TRIBUTARY AREA TO RAIN ® 2� oN -� \ / °s°.•,;.,._: ;:: :;: : / / / GARDEN NO. 2= 0.51 a ACRES Z N FFE= 4897.30 4892 \ I 1 I TOTAL MODIFIED AREA =1.33 ACRES 9•;. _ J E w C) 48 - 93 s - P / 4896 s° NEW TURF FIELD I• s P _ _ _ -4 I ss _ ;= � U Lu 48°97 CC F- \ I / \ / ♦ \ co Z O LL e.s,. .� , .P. _. I� D _ °s D. _ ♦ •D / � \ � I I I I I 1 1 O I oz O v ;s FFE=4897.30 I I I I I I Q = \ I .. I I I I I I FFE=4896.00 1 co I N C) i O>N I I N I I to Co co - _ •y o / .. - . ' ` :e ..r `.. .. '2,�0\' . . 4 r�/ �' tie-•-,-.' x o M O m O g e S : I ® I I I w 74896� " s I a Q o ' 1 \ P ' A. CL � I \ s ,'.. s ^s �rn> . . >..s • s. Ps: I I 4895 \ I . .° P /� I • - P I ` I \ ta ♦ o 0 0 o e o 0 0 ♦ o S -; Y- t°. •'' / SB r S"r... ° e1 I ^ �. / s I •4895- zs _I I r 1 I � � I 4895 I s r P "s y 's'°.... °s cis I I ! _ y c /10 00 �J4895 � P, ' P ° P �e w q e ys l tG / f + \ � � I •6 / , . ° g �> _ems t 4896- �` �� . , � s °. s . \ ° . s. .: - - - I-4896- JA0O 1 y P' - F 1 4897 I RRr RRrrr '-RtRr RRr Rt -RR ,. F- m c� x o TOTAL MODIFIED AREA: AREA TRIBUTARY TO WATER QUALITY FACILITY 1 : AREA TRIBUTARY TO WATER QUALITY FACILITY 2: = W Q EQ. 7.1 : WQCV=0.8[(0.91 *I^3)-(1 .19*I^2)+(0.78*1)] EQ. 7.1 : WQCV=0.8[(0.91 *I^3)-(1 .19*I^2)+(0.78*1)] EQ. 7.1 : WQCV=0.8[(0.91 *I^3)-(1 .19*I^2)+(0.78*1)] z j N a = 0.8 a = 0.8 a = 0.8 Q V N O Q I = 0.62 I = 0.70 I = 0.48 � � 3 � Z WQCV = 0.8[0.91 *(0.62^3)-1 .19*(0.62^2)+0.78*0.62] = 0.19 WATERSHED INCHES WQCV = 0.8[0.91 *(0.70^3)-1 .19*(0.70^2)+0.78*0.70] = 0.22 WATERSHED INCHES WQCV = 0.8[0.91 *(0.48^3)-1 .19*(0.48^2)+0.78*0.48] = 0.16 WATERSHED INCHES J w O W p EQ. 7.2: V=(WQCV/12)*A EQ. 7.2: V=(WQCV/1 2)*A EQ. 7.2: V=(WQCV/12)*A V V Q A=1 .33 AC A=0.90 AC A=0.51 AC ckf V=(0.19/12)*1 .33 = 0.02 AC-FT = 917 CF REQUIRED V=(0.22/12)*0.90 = 0.016 AC-FT = 719 CF REQUIRED V=(0.16/12)*0.51 = 0.01 AC-FT = 297 CF REQUIRED m LL 0 J a O co 0 E E U J O N O N O N V7 U SHEET cn 30 0 30 60 N SCALE IN FEET 0 0 JOB#: 2024020 Elevation DATE: 4/22/2025 Consulting PROJECT: Liberty Common Junior High SUBJECT: Rain Garden#1 Drainage Area= 0.90 acres Required WQCV= 719 cf Available Volume = 990 SEDIMENT BASIN VOLUME SUMMARY Contour Total Area H Volume Cumulative Cumulative Elev Volume Volume (ft) (ft2) (ft) (ft3) (ft3) ac-ft 4892.5 603 0 1.0 990 4893.5 1436 990 0.023 JOB#: 2024020 Elevation DATE: 4/22/2025 Consulting PROJECT: Liberty Common Junior High SUBJECT: Rain Garden#2 Drainage Area= 0.51 acres Required WQCV= 297 cf Available Volume = 302 SEDIMENT BASIN VOLUME SUMMARY Contour Total Area H Volume Cumulative Cumulative Elev Volume Volume (ft) (ft2) (ft) (ft3) (ft3) ac-ft 4892.5 175 0 1.0 302 4893.5 450 302 0.007 Final Drainage Report Liberty Common Junior High Fort Collins, Colorado APPENDIX B HYDRAULIC COMPUTATIONS Elevation Consulting 15 Worksheet for March Court DPI flow Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Channel Slope 0.008 ft/ft Discharge 12.80 cfs Section Definitions Station Elevation (ft) (ft) 0+00.0 4,897.95 0+04.0 4,897.88 0+04.5 4,897.41 0+06.5 4,897.53 0+22.5 4,897.92 0+38.5 4,897.29 0+40.5 4,897.15 0+41.0 4,897.62 0+44.0 4,897.72 Roughness Segment Definitions Start Station Ending Station Roughness Coefficient (0+00.0,4,897.95) (0+44.0,4,897.72) 0.016 Options Current Roughness Weighted Pavlovskii's Method Method Open Channel Weighting Pavlovskii's Method Method Closed Channel Weighting Pavlovskii's Method Method Results Normal Depth 6.8 in Roughness Coefficient 0.016 Elevation 4,897.71 ft Elevation Range 4,897.15 to 4,897.95 ft Flow Area 4.8 ft2 Wetted Perimeter 26.25 ft Hydraulic Radius 2.2 in Top Width 25.92 ft Normal Depth 6.8 in Critical Depth 6.9 in Critical Slope 0.007 ft/ft Velocity 2.67 ft/s Bentley Systems,Inc. Haestad Methods Solution FlowMaster Untitled 1.fm 8 Center [10.03.00.03] 3/3/2025 27 Siemon Company Drive Suite 200 W Page 1 of 2 Watertown,CT 06795 USA +1-203-755-1666 Worksheet for March Court DPI flow Results Velocity Head 0.11 ft Specific Energy 0.67 ft Froude Number 1.096 Flow Type Supercritical GVF Input Data Downstream Depth 0.0 in Length 0.00 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.0 in Profile Description N/A Profile Headloss 0.00 ft Downstream Velocity Infinity ft/s Upstream Velocity Infinity ft/s Normal Depth 6.8 in Critical Depth 6.9 in Channel Slope 0.008 ft/ft Critical Slope 0.007 ft/ft Bentley Systems,Inc. Haestad Methods Solution FlowMaster Untitled 1.fm 8 Center [10.03.00.03] 3/3/2025 27 Siemon Company Drive Suite 200 W Page 2 of 2 Watertown,CT 06795 USA +1-203-755-1666 Cross Section for March Court DP1 flow Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Channel Slope 0.008 ft/ft Normal Depth 6.8 in Discharge 12.80 cfs 4898.20 4898.10 4898.00 4897.90 -- ----------i- 4897.80 - - . e 4897.70 -- --- ----- ------ 4897.60 ru - - > 4897.50 - - --- "' 4897.40 4897.30 - 4897.20 4897.10 4897.00 - 4896.90 0+00 0+10 0+20 0+30 0+40 Station Bentley Systems,Inc. Haestad Methods Solution FlowMaster Untitled 1.fm 8 Center [10.03.00.03] 3/3/2025 27 Siemon Company Drive Suite 200 W Page 1 of 1 Watertown,CT 06795 USA +1-203-755-1666 Collection Capacity of Horizontal Orifice (Inlet Control) Project: Liberty Common Junior High Basin ID: 1825 Sharp Point Inlet(south parking lot) circular box opening area opening area outlet and Outlet and structure Perimeter Structure perimeter flow flow Culvert Culvert Design Information (Input): Circular Opening: Diameter Dia. = ft. OR Rectangular Opening: Width W = 2.00 ft. Length L = 2.00 ft. Percentage of Open Area After Trash Rack Reduction % open = 50.00 % Orifice Coefficient Co= 0.67 Weir Coefficient CW= 3.00 Orifice Elevation Eo= 4894.88 ft. Calculation of Collection Capacity: Net Opening Area (after Trash Rack Reduction) Ao= 2.00 sq. ft. Perimeter as Weir Length LW= 8.00 ft. Enter water surface elevations in ascending order. Water Weir Orifice Collection Surface Flow Flow Capacity Elevation cfs cfs cfs ft (input) (output) (output) (output) start 4895.00 1.00 3.73 1.00 4895.10 2.48 5.04 2.48 4895.20 4.34 6.08 4.34 3 inlets=13.02 cfs > 9.6 cfs for 0 Basin EX1-A 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Inlet Capacity Calc.xls, Existing 3/3/2025, 1:18 PM Collection Capacity of Horizontal Orifice (Inlet Control) Project: Liberty Common Junior High Basin ID: Design Point 7 Area Inlet circular box opening area opening area outlet and Outlet and structure Perimeter Structure perimeter flow flow Culvert Culvert Design Information (Input): Circular Opening: Diameter Dia. = ft. OR Rectangular Opening: Width W = 1.35 ft. Length L = 1.98 ft. Percentage of Open Area After Trash Rack Reduction % open = 50.00 % Orifice Coefficient Co= 0.67 Weir Coefficient CW= 3.00 Orifice Elevation Eo= 4894.63 ft. Calculation of Collection Capacity: Net Opening Area (after Trash Rack Reduction) Ao= 1.34 sq. ft. Perimeter as Weir Length LW= 6.66 ft. Enter water surface elevations in ascending order. Water Weir Orifice Collection Surface Flow Flow Capacity Elevation cfs cfs cfs ft (input) (output) (output) (output) start 4894.70 0.37 1.90 0.37 4894.80 1.40 2.96 1.40 4894.90 2.80 3.73 2.80 > DP7 Q100 = 2.4 cfs 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Inlet Capacity Calc.xls, Existing 3/3/2025, 1:23 PM 1825 SHARP POINT STORM 2 year storm: Conduit Table Label Start Invert Stop Invert(Stop) Length Slope Section Diameter Manning's n Flow Velocity Depth(Out) Capacity(Full Flow/ Hydraulic Grade Hydraulic Grade Energy Grade Energy Grade Node (Start) Node (ft) (Scaled) (Calculated) Type (in) (cfs) (ft/s) (ft) Flow) Capacity Line(In) Line(Out) Line(In) Line(Out) (ft) (ft) (ft/ft) (cfs) (Design) (ft) (ft) (ft) (ft) CO-1 C13-1 4,892.75 C13-4 4,890.57 211.3 0.010 Circle 12.0 0.011 0.75 4.09 0.62 4.28 17.5 4,893.11 4,891.19 4,893.24 4,891.22 CO-2 C13-2 4,892.57 C13-4 4,890.57 208.4 0.010 Circle 12.0 0.011 0.72 3.94 0.62 4.12 17.4 4,892.92 4,891.19 4,893.05 4,891.22 CO-3 C13-3 4,892.77 C13-4 4,890.57 212.0 0.010 Circle 12.0 0.011 0.75 4.10 0.62 4.29 17.4 4,893.13 4,891.19 4,893.26 4,891.22 CO-4 C13-4 4,890.46 0-1 4,889.66 89.1 0.009 Circle 24.0 0.013 4.29 5.33 0.61 21.43 20.0 4,891.19 4,890.27 4,891.46 4,890.71 StormCAD 2024020-PROPOSED STORM MODEL 5 year.stsw Bentley Systems,Inc. Haestad Methods Solution Center [10.03.04.53] 3/3/2025 76 Watertown Road,Suite 2D Thomaston,CT 06787 USA +1-203-755-1666 Page 1 of 1 1825 SHARP POINT STORM Profile Report Engineering Profile - Profile - 1 (2024020 - PROPOSED STORM MODEL 2 year.stsw) CB-1 Rim:4,894.88 ft CB-4 Invert:4,892.75 It Rim:4,894.38 ft Invert:4,890.46 ft 4,895.00 _ O-1 r Rim:4,889.66 ft ,v CO-1:211. Invert:4,889.66 ft 3 ft @ 0.010 fVft Circle- 4,890.00 12,0 in CO-4:89.1ft 0.009 ft/ft d Circle-2q 0 in w 4,885.00 -0+50 0+00 0+50 1+00 1+50 2+00 2+50 3+00 3+50 Station(ft) Element ID\Label 57\CO-1 58\CO-4 Length(Unified)(ft) 211.3 89.1 Rise(Unified)(ft)\Material 1.00\ 2.00\ Flow(cfs) 0.75 4.29 Slope(Calculated)(ft/ft) 0.010 0.009 Element ID\Label 54\CB-1 55\CB-4 56\IO-1 Elevation(Ground)(ft) 4,894.88 4,894.38 4,8$9.66 Elevation(Invert)(ft) 4,892.75 4,890.46 4,889.66 Station(ft) 0+00 2+11 3+00 2024020-PROPOSED STORM MODEL 5 Bentley Systems,Inc. Haestad Methods Solution StormCAD year.stsw Center [10.03.04.531 3/3/2025 76 Watertown Road,Suite 2D Thomaston,CT Page 1 of 1 06787 USA +1-203-755-1666 1825 SHARP POINT STORM Profile Report Engineering Profile - Profile - 2 (2024020 - PROPOSED STORM MODEL 2 year.stsw) CB-2 RiCICO5-2.208.4 :489481 ft CB-4 Rim:4,894.38 ft Invert:4,890.46 ft 4,895.00 ft 0.010 ft/k O-1 ,ircle- Rim:4,889.66 ft F Invert:4,889.66 ft c 4,890.00 m w 4,885.00 -0+50 0+00 0+50 1+00 1+50 2+00 2+50 3+00 Station(ft) Element ID\Label 62\CO-2 58\CO-4 Length(Unified)(ft) 208.4 89.1 Rise(Unified)(ft)\Material 1.00\ 2.00\ Flow(cfs) 0.72 4.29 Slope(Calculated)(ft/ft) 0.010 0.009 Element ID\Label 61\CB-2 55\CB-4 56\0-1 Elevation(Ground)(ft) 4,894.81 4,894.38 4,889.66 Elevation(Invert)(ft) 4,892.57 4,890.46 4,889.66 Station(ft) 0+00 2+08 2+98 2024020-PROPOSED STORM MODEL 5 Bentley Systems,Inc. Haestad Methods Solution StormCAD year.stsw Center [10.03.04.53] 3/3/2025 76 Watertown Road,Suite 2D Thomaston,CT Page 1 of 1 06787 USA +1-203-755-1666 1825 SHARP POINT STORM Profile Report Engineering Profile - Profile - 3 (2024020 - PROPOSED STORM MODEL 2 year.stsw) CB-3 Rim:4,894.80 ft CB-4 Invert:4,892.77 ft Rim:4,894.38 ft Invert:4,890.46 ft 4,895.00 CO-3:272.Oft 0.010 ft/(t 0-1 Rim:4,889.66 R Invert:4,889.66ft C 4,890.00 - -w - 4,885.00 - -0+50 0400 0+50 1+00 1+50 2+00 2+50 3+ 0 3+50 Station(ft) Element ID\Label 60\C0-3 58\CO4 Length(Unified)(ft) 212.0 89.1 Rise(Unified)(ft)\Material 1.00\ 2.00\ Flow(cfs) 0.75 4.29 Slope(Calculated)(ft/ft) 0.01.0 0.009 Element ID\Label 59\ B-3 W 6-4 560-1 Elevation(Ground)(ft) 4,894.80 4,894.38 4,889.66 Elevation(Invert)(ft) 4,8 2.77 4,890.46 4,889.66 Station(ft) 0100 2,1112 3101 2024020-PROPOSED STORM MODEL 5 Bentley Systems,Inc. Haestad Methods Solution StormCAD year.stsw Center [10.03.04.531 3/3/2025 76 Watertown Road,Suite 21D Thomaston,CT Page 1 of 1 06787 USA +1-203-755-1666 1825 SHARP POINT STORM 100 year storm: Conduit Table Label Start Invert Stop Invert(Stop) Length Slope Section Diameter Manning's n Flow Velocity Depth(Out) Capacity Flow/ Hydraulic Grade Hydraulic Grade Energy Grade Energy Grade Node (Start) Node (ft) (Scaled) (Calculated) Type (in) (cfs) (ft/s) (ft) (Full Flow) Capacity Line(In) Line(Out) Line(In) Line(Out) (ft) (ft) (ft/ft) (cfs) (Design) (ft) (ft) (ft) (ft) (%) CO-1 C13-1 4,892.75 C13-4 4,890.57 211.3 0.010 Circle 12.0 0.011 3.21 5.97 1.43 4.28 75.0 4,893.52 4,892.00 4,893.90 4,892.26 CO-2 C13-2 4,892.57 C13-4 4,890.57 208.4 0.010 Circle 12.0 0.011 3.21 5.80 1.43 4.12 77.8 4,893.34 4,892.00 4,893.72 4,892.26 CO-3 C13-3 4,892.77 C13-4 4,890.57 212.0 0.010 Circle 12.0 0.011 3.21 5.99 1.43 4.29 74.8 4,893.54 4,892.00 4,893.92 4,892.26 CO-4 C13-4 4,890.46 0-1 4,889.66 89.1 0.009 Circle 24.0 0.013 18.23 7.66 1.42 21.43 85.0 4,892.00 4,891.08 4,892.77 4,891.99 StormCAD 2024020-PROPOSED STORM MODEL.stsw Bentley Systems,Inc. Haestad Methods Solution Center [10.03.04.53] 3/3/2025 76 Watertown Road,Suite 2D Thomaston,CT 06787 USA +1-203-755-1666 Page 1 of 1 1825 SHARP POINT STORM Profile Report Engineering Profile - Profile - 1 (2024020 - PROPOSED STORM MODEL.stsw) CB-1 Rim:4,894.88 ft CB-4 Invert:4,892.75 It Rim:4,894.38 ft Invert:4,890.46 It 4,895.00 _ O-1 Rim:4,889.66 ft ,v CO-1:271.3 ft @ 0.010 ft/ft Invert:4,889.66 ft Circle- 12..0 in CO-4:89.1 ft @ 0.009 ft/ft d Circle-24 0 in w 4,885.00 -0+50 0+00 0+50 1+00 1+50 2+00 2+50 3+00 3+50 Station(ft) Element ID\Label 57\C0-1 58\CO-4 Length(Unified)(ft) 211.3 89.1 Rise(Unified)(ft)\Material 1.00\ 2.00\ Flow(cfs) 3.21 18.23 Slope(Calculated)(ft/ft) 0.010 0.009 Element ID\Label 54\CB-1 55\CB-4 56\IO-1 Elevation(Ground)(ft) 4,894.88 4,894.38 4,8$9.66 Elevation(Invert)(ft) 4,892.75 4,890.46 4,889.66 Station(ft) 0+00 2+11 3+00 Bentley Systems,Inc. Haestad Methods Solution StormCAD 2024020-PROPOSED STORM MODEL.stsw Center [10.03.04.531 3/3/2025 76 Watertown Road,Suite 2D Thomaston,CT Page 1 of 1 06787 USA +1-203-755-1666 1825 SHARP POINT STORM Profile Report Engineering Profile - Profile - 2 (2024020 - PROPOSED STORM MODEL.stsw) CB-2 Rim:4,894.81 ft CB-4 Invert:4,892.57 ft Ri4894.38 ft 890.46 ft 4,895.00ji;nvert: O-1 Circle-12.0 in Rim:4,889.66ft c e- Invert:4,889.66 ft c 4,890.00 - m w 4,885.00 -0+50 0400 0+50 1+00 1+50 2+00 2+50 3 00 Station(ft) Element ID\Label 62\CO-2 58\CO.4 Length(Unified)(ft) 208.4 89.1 Rise(Unified)(ft)\Material 1.00\ 2.00\ Flow(cfs) 3.21 18.23 Slope(Calculated)(fVft) 0.010 0,009 Element ID\Label 61\ B-2 55\ B-4 56\ -1 Elevation(Ground)(ft) 4,894.81 4,8G 4.38 4,8 .66 Elevation(Invert)(ft) 4,892.57 4,8 :46 4,885.66 Station(ft) 0�00 2�08 2 8 Bentley Systems,Inc. Haestad Methods Solution StormCAD 2024020-PROPOSED STORM MODEL.stsw Center [10.03.04.53] 3/3/2025 76 Watertown Road,Suite 2D Thomaston,CT Page 1 of 1 06787 USA +1-203-755-1666 1825 SHARP POINT STORM Profile Report Engineering Profile - Profile - 3 (2024020 - PROPOSED STORM MODEL.stsw) CB-3 Rim:4,894.80 ft CB-4 Invert:4,892.77 ft Rim:4,894.38 ft Invert:4,890.46 ft 4,895.00 01 e- 2.0 in - Rim:4,889.661� irc e- Invert:4,889.66 ft c n_ m 4,890.00 — —w — 4,885.00 — - -0+50 0+00 0+50 1+00 1+50 2+00 2+50 3+ 0 3+50 Station(ft) Element ID\Label 60\CO-3 58\CO4 Length(Unified)(ft) 212.0 89.1 Rise(Unified)(ft)\Material 1.00\ 2.00\ Flow(cfs) 3.21 18.23 Slope(Calculated)(ft/ft) 0.010 0.009 Element ID\Label 59\ B-3 55\ 6-4 560-1 Elevation(Ground)(ft) 4,894.80 4,894.38 4,889.66 Elevation(Invert)(ft) 4,8 2.77 4,890.46 4,889.66 Station(ft) 0100 2,1112 3101 Bentley Systems,Inc. Haestad Methods Solution StormCAD 2024020-PROPOSED STORM MODEL.stsw Center [10.03.04.53] 3/3/2025 76 Watertown Road,Suite 2D Thomaston,CT Page 1 of 1 06787 USA +1-203-755-1666 New Addition roof drain Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.011 Channel Slope 0.010 ft/ft Diameter 12.0 in Discharge 2.61 cfs Results Normal Depth 6.8 in Flow Area 0.5 ft2 Wetted Perimeter 1.7 ft Hydraulic Radius 3.2 in Top Width 0.99 ft Critical Depth 8.3 in Percent Full 57.0 % Critical Slope 0.006 ft/ft Velocity 5.65 ft/s Velocity Head 0.50 ft Specific Energy 1.07 ft Froude Number 1.457 Maximum Discharge 4.53 cfs Discharge Full 4.21 cfs Slope Full 0.004 ft/ft Flow Type Supercritical GVF Input Data Downstream Depth 0.0 in Length 0.0 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.0 in Profile Description N/A Profile Headloss 0.00 ft Average End Depth Over Rise 0.0 % Normal Depth Over Rise 57.0 % Downstream Velocity Infinity ft/s Upstream Velocity Infinity ft/s Normal Depth 6.8 in Critical Depth 8.3 in Channel Slope 0.010 ft/ft Critical Slope 0.006 ft/ft Bentley Systems,Inc. Haestad Methods Solution FlowMaster pipe capacities.fm8 Center [10.03.00.03] 4/22/2025 27 Siemon Company Drive Suite 200 W Page 1 of 1 Watertown,CT 06795 USA +1-203-755-1666 Design Point 7 outfall pipe Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.011 Channel Slope 0.005 ft/ft Diameter 12.0 in Discharge 2.40 cfs Results Normal Depth 8.2 in Flow Area 0.6 ft2 Wetted Perimeter 1.9 ft Hydraulic Radius 3.5 in Top Width 0.93 ft Critical Depth 8.0 in Percent Full 68.0 % Critical Slope 0.005 ft/ft Velocity 4.22 ft/s Velocity Head 0.28 ft Specific Energy 0.96 ft Froude Number 0.952 Maximum Discharge 3.20 cfs Discharge Full 2.98 cfs Slope Full 0.003 ft/ft Flow Type Subcritical GVF Input Data Downstream Depth 0.0 in Length 0.0 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.0 in Profile Description N/A Profile Headloss 0.00 ft Average End Depth Over Rise 0.0 % Normal Depth Over Rise 54.1 % Downstream Velocity Infinity ft/s Upstream Velocity Infinity ft/s Normal Depth 8.2 in Critical Depth 8.0 in Channel Slope 0.005 ft/ft Critical Slope 0.005 ft/ft Bentley Systems,Inc. Haestad Methods Solution FlowMaster pipe capacities.fm8 Center [10.03.00.03] 3/3/2025 27 Siemon Company Drive Suite 200 W Page 1 of 1 Watertown,CT 06795 USA +1-203-755-1666 Final Drainage Report Liberty Common Junior High Fort Collins, Colorado APPENDIX C REFERENCED INFORMATION Elevation Consulting 16 FORT COLLINS STORMWATER CRITERIA MANUAL Preface 2.0 Purpose In addition, this Manual recognizes the various Master Drainage Plans that have been developed for all the major drainage basins within and around Fort Collins. Each Master Drainage Plan provides detailed analysis and selected plan improvement guidance for major stormwater infrastructure needs throughout Fort Collins and its GMA, see Figure 2.0-1 below. This Manual directs users to apply allowable release rates for storm drainage that have been established by the various Master Drainage Plans and to incorporate any selected plan improvements (where appropriate) into their design. This Manual does not provide direction or requirements for Master Drainage Plan updates. Figure 2.0-1. Master Drainage Basin Map with City Limits and GMA I COO ER DRY SLOUGHI0 ELDER .REEK BA TIN MICHAU❑WEST VINE BASIN c I —JLL OLD TOWN BASIN ' I "� - ��'� CANAL IMPORTATION j BASINCN � r--r - �LAPOUDRE ~l BASIN I 'I FOOTHILLS BASIN '1 I FOX i } -----' MAIL MEADOWS 1 CREEK BASIN / I I BASIN I_l ,nl MCCLELLANDS • BASIN L_J FOSSIL CREEK I I .^_.II ti BASIN L I(� I `_J , I I j I` �l L-•� i ''� Esri,HERE.De Lo rnie.M!pmyld r OpanStraetMap cdnl tri tutors,and the GIS user -----J community fit—' Cityof 2.0 Purpose Fort Collins Page 2 National Flood Hazard Layer FIRMette (.. FEMA Legend 105°2'1"W 40033'58"N SEE FIS REPORT FOR DETAILED LEGEND AND INDEX MAP FOR FIRM PANEL LAYOUT ggpp FEET 490�FEET Without Base Flood Elevation(BFE) 4.• Zone A.V.A99 SPECIAL FLOOD With BFE or Depth Zone AE.AO.AH.VE.AR HAZARD AREAS Regulatory Floodway A 0.2%Annual Chance Flood Hazard,Areas F of 1%annual chance flood with average depth less than one foot or with drainage A�p�gF areas of less than one square mile zonex Zone A ® Future Conditions 1%Annual s ®� Chance Flood Hazard Zone -� L�MR -0�SP Area with Reduced Flood Risk due to efij2RU2010 OTHER AREAS OF Levee.See Notes.zone x FLOOD HAZARD Area with Flood Risk due to Levee zone o NO SCREEN Area of Minimal Flood Hazard zone x Q Effective LOMRs 1 a0 1 OTHER AREAS Area of Undetermined Flood Hazard zone o 4 --GENERAL - - Channel,Culvert,or Storm Sewer STRUCTURES IIIIIII Levee,Dike,or Floodwall - : p�� A• �� &-MA Cross Sections with 1%Annual Chance Aa93' A�3 17.5 Water Surface Elevation `CIty.Of Fort Colluis] CI /1/7111�A/AV e- - - Coastal Transect O 1 rr LV V V•rill -513- Base Flood Elevation Line(BFE) �0�102WSZOE Limit of Study r 1RNw S� Jurisdiction Boundary Coastal Transect Baseline AREA OF MINIMAL FLOOD HAZA I _,t��`' OTHER _ - Profile Baseline FEATURES Zone X EET�92 F Hydrographic Feature 4892 FEET SITE Digital Data Available N ET No Digital Data Available 4891.E FE _ MAP PANELS Unmapped g1 FE - O 11a The pin displayed on the map is an approximate point selected by the user and does not represent # an authoritative property location. tW This map complies with FEMA's standards for the use of digital flood maps if it is not void as described below. _ IM ,.gyp FEES The basemap shown complies with FEMA's basemap A '9 accuracy standards fF The flood hazard information is derived directly from the authoritative NFHL web services provided by FEMA.This map was exported on 10/28/2024 at 9:00 PM and does not reflect changes or amendments subsequent to this date and time.The NFHL and effective information may change or become superseded by new data over time. �i This map image is void if the one or more of the following map elements do not appear:basemap imagery,flood zone labels, legend,scale bar,map creation date,community identifiers, 105°1'23"W 40°33'31"N FIRM panel number,and FIRM effective date.Map images for Feet 1:6 000 unmapped and unmodernized areas cannot be used for 0 250 500 1,000 1,500 2,000 regulatory purposes. Basemap Imagery Source:USGS National Map 2023 Hydrologic Soil Group—Larimer County Area,Colorado � M io 0 0 497350 497390 497430 497470 497510 497550 497590 497630 497670 497710 40°33'48"N — 40°33'48"N '` Soil Map may not b2 uald at this scale. 'E7 40°33'40"N I - .2" • -• 40°33 40"N 497350 497390 497430 497470 497510 497550 497590 497630 497670 497710 3 3 Map Scale:1:1,760 if printed on A landscape(11"x 8.5")sheet N Meters ° 0 25 50 100 150 Feet 0 50 100 200 300 Map projection:Web Mercator Comer coordinates:WGS84 Edge tics:UTM Zone 13N WGS84 USDA Natural Resources Web Soil Survey 3/2/2025 Conservation Service National Cooperative Soil Survey Page 1 of 4 Hydrologic Soil Group—Larimer County Area,Colorado MAP LEGEND MAP INFORMATION Area of Interest(AOI) 0 C The soil surveys that comprise your AOI were mapped at Area of Interest(AOI) 0 CID 1:24,000. Soils © D Warning:Soil Map may not be valid at this scale. Soil Rating Polygons A Not rated or not available Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil F—] AID Water Features line placement.The maps do not show the small areas of Streams and Canals contrasting soils that could have been shown at a more detailed 0 B scale. Transportation B/D *.. Rails Please rely on the bar scale on each map sheet for map 0 C measurements. � Interstate Highways 0 C/D US Routes Source of Map: Natural Resources Conservation Service Web Soil Survey URL: 0 D Major Roads Coordinate System: Web Mercator(EPSG:3857) 0 Not rated or not available Local Roads Maps from the Web Soil Survey are based on the Web Mercator Soil Rating Lines Background projection,which preserves direction and shape but distorts q distance and area.A projection that preserves area,such as the Aerial Photography Albers equal-area conic projection,should be used if more .-.. AID accurate calculations of distance or area are required. ++� B This product is generated from the USDA-NRCS certified data as ti B/D of the version date(s)listed below. C Soil Survey Area: Larimer County Area,Colorado Survey Area Data: Version 19,Aug 29,2024 r.i CID Soil map units are labeled(as space allows)for map scales ... D 1:50,000 or larger. Not rated or not available Date(s)aerial images were photographed: Jul 2,2021—Aug 25, Soil Rating Points 2021 p A The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background E3 AID imagery displayed on these maps.As a result,some minor B shifting of map unit boundaries may be evident. B/D USDA Natural Resources Web Soil Survey 3/2/2025 Conservation Service National Cooperative Soil Survey Page 2 of 4 Hydrologic Soil Group—Larimer County Area,Colorado Hydrologic Soil Group Map unit symbol Map unit name Rating Acres in AOI Percent of AOI 22 Caruso clay loam,0 to 1 D 2.4 31.5% percent slope 64 Loveland clay loam,0 to C 5.0 64.2% 1 percent slopes 105 Table Mountain loam,0 B 0.3 4.3% to 1 percent slopes Totals for Area of Interest 7.8 100.0% Description Hydrologic soil groups are based on estimates of runoff potential. Soils are assigned to one of four groups according to the rate of water infiltration when the soils are not protected by vegetation, are thoroughly wet, and receive precipitation from long-duration storms. The soils in the United States are assigned to four groups (A, B, C, and D)and three dual classes (A/D, B/D, and C/D). The groups are defined as follows: Group A. Soils having a high infiltration rate (low runoff potential)when thoroughly wet. These consist mainly of deep, well drained to excessively drained sands or gravelly sands. These soils have a high rate of water transmission. Group B. Soils having a moderate infiltration rate when thoroughly wet. These consist chiefly of moderately deep or deep, moderately well drained or well drained soils that have moderately fine texture to moderately coarse texture. These soils have a moderate rate of water transmission. Group C. Soils having a slow infiltration rate when thoroughly wet. These consist chiefly of soils having a layer that impedes the downward movement of water or soils of moderately fine texture or fine texture. These soils have a slow rate of water transmission. Group D. Soils having a very slow infiltration rate (high runoff potential)when thoroughly wet. These consist chiefly of clays that have a high shrink-swell potential, soils that have a high water table, soils that have a claypan or clay layer at or near the surface, and soils that are shallow over nearly impervious material. These soils have a very slow rate of water transmission. If a soil is assigned to a dual hydrologic group (A/D, B/D, or C/D), the first letter is for drained areas and the second is for undrained areas. Only the soils that in their natural condition are in group D are assigned to dual classes. USDA Natural Resources Web Soil Survey 3/2/2025 Conservation Service National Cooperative Soil Survey Page 3 of 4 Hydrologic Soil Group—Larimer County Area,Colorado Rating Options Aggregation Method: Dominant Condition Component Percent Cutoff: None Specified Tie-break Rule: Higher USDA Natural Resources Web Soil Survey 3/2/2025 Conservation Service National Cooperative Soil Survey Page 4 of 4 1 Oil 41 ..��•.� ICE . . Ilia ' �:' ,:=�� IElaA1► ' - • ' ' '' ,� Legend Reservoirs, Lakes, Ponds Evacuabon Routes Ili► • �� - ., • • Railroad Tracks Schools0 Fire ♦- - ( �' f . Police Depth of Water Over 1-21 feet .. 0-1 feet �. 2+ feet IP 00-year Floodplain - at rivet idence Div rsi h,OUNTtIN VISTA ft to n Mobile Le� ` � Z • a , X LL e enu pt Vin r < PORTt VE u uCki �� Par)L v o w`y ER sT + IS ay ve KYk Ly 1 SITE ysl4f tes Lev wP 0 4 E 48.1 f_ Pf 0 'EC' pect nd Cons ruct Bypass w rrr T N 0 _ z r m Z City of fort Collim p i Master Plan Basin o Recommended Improwirwft m A E MORB O RO O l+►rntw,rM!..Kars.rdR090Res►p / Z a i �� Hr e amo E ARMCNpp�i+. NTY ROA: A-' �aor grco r m Final Drainage Report Liberty Common Junior High Fort Collins, Colorado APPENDIX D DRAINAGE MAP Elevation Consulting 17 m m EX. 24" RCP W/ FES m EX. STRM INLET 0 w Y U EX. 24" RCP W/ FES EX. 24" RCP W/ FES / SHARP POINT DRIVE o OS8 = \ w o - -4894896- \ o EX. STRM INLET 0.02 2% \ I I - \ � AC. \� / \ o D. \ m ° 4 4896 o • co ... - 4896 _ AC. 4895.84 z o D . � s e.. 3 o Ld 4895.66 \ o 0 o EX. STRM INLET k OqC s9% cn000 - 04893 I �� 961/i �4895395- z �� EX1O 4 � �I A89 �� _ , z W EX. COBBL� I= "'" , 4896 1 1� 'n 0.56 65% EX. STRM INLET � .:: m W _ DRAINAGE 1 = _ I o o AC. I 1 �` - �- C'3 IX 1- CHANNEL -489,4894 - - / Q Q FT co _ Ir \ 4897.45 ,y . ..y.. -. _ ._ y. � -� °�'° EX CO CR TE _ _ _ ." 1I _ � �� L � ANL � V Q ~ EX. ' - \. ' I ° - 4895 - �� z ° • . �' O Z O z ESA EX. DRAINAGE i \ / 1 EX. COBBLE - I - - _ Z O H O � o I PER P T I / �� X. �3) 12' STRM DRAINAGE - : I. V ero / -v mac, ^� \ 1 I I CHANNEL UNDER \\ 1 - ,_ rEX9 2 <c/ I \ / / CHANNEL d ( - �� ° (n moo. 0 X�. / WALKWAY I (� `\ I 0.04 2% II (`EX2 _ N \ / EX. ROOF DRAIN 'i 1 ��\ EX. CONCRETE DRAINAGE \ D , AC. _ CHANNEL UNDER WALKWAY z \ I v 0.44 EXISTING BUILDING " , , I EX. GRASS SWALE AC Q 1 1 1825 SHARP POINT DRIVE ImI EXISTING BUILDING FFE=4897.30' 1901 SHARP POINT DRIVE LOTS I I EX. ROOF DRAIN I N Lo a I�IPONTATPRosPECT - I W FFE=4896.00 EX. 15' EX8 l N PARKEAST I _ 4897.05 EX. 15 ESMT I ,, 100 \ PER PLAT EX. GRASS SWALE I _ EX11 ESMT PER 0.23 90% I , I, 00 o N EX3 / / EX. METAL DRAINAGE CHASE I 0.23 90% PLAT qC. OTr2 o 0 0 0.09 13% *. I AC. I 1 I P OSPECT m 0 AC. 2 4897.40 ` w u RIA o LPARK q w w 4897.00 EX. COBBLE DRAINAGE I CL Q RIGHT-OF-WAY . _ _ _ EX. (2) 12 STRM CHANNEL J LINE, TYP. / _ .A . .. _ - / 4897.86 E�12=�VCSTR - i E � 6 4�896.f1 I s .: . \ -Fo 1 EX. 12" STRM y 4r96.451 EX. 12 STRM EX. STRM INLET I s s�: \ 1 EX. 12" PVC STRM 48 7.26 EX7 00 d. c m \ EX1 1 w EX. COBBLE / EX5 1 4895.82 4L7.45 48951 EX. CONCRETE / � y. \ 0.73 87% cn I DRAINAGE o.58 78% - � AC. 1 1 EX. STRM INLET I CHANNEL / AC. ` AC. I DRAIN PAN _ I ;s EX. METAL I \ 4895- I I / I E ESM � _ \ DRAINAGE CHASE �� I\ / ( ER PLAT - y 00 4898.15 I EX. STRM I LET' E 1 �' - / 1 5 i OS5 ' \ j - EX. TRM INLET 4 ;s �0ow � EX. STRM INLET EX. 12 PVC \ 4897.829 I I 4895 ) 0.012% AC. \ y W I / 489f7.86 I j �_ EX6 \ >� •:. / 1 CONCRETE AC. 1 � / � � / I I 0.28 97% / EX. \ y/ / \ 4896 4896 9--489 FO RRr RRr Rr -ZRRr er _ _ _ _ _ EX. kTAL 4896.86 1 OS7 - Q - Q1 Df AINAGE _ -EX. CONCRETE DRAINAGE � ,� _ 'CH NNEL UNDER WALKWAY/ �- � LLJ AC. 64q_cll-il� �" � - - � EX. CONCRETE DRAINAGE \ EX. 10 PVC OUTFALL - PROPERTY LINE, TYP. CHANNEL UNDER WALKWAY LOT_? I I OS2 I I \=RF STRM \ PROSPECT 1 I 1.45 38% / INDUSTRIAL PARK � � A� \ OS3 I I� �R OS4 LOTH = � LOT' LOT LINE TYP. -}� \\ / 1.24 90% PROSPECT V Q O PROSPECT LOT6 AC 0.54 90% INDUSTRY-IL PARK INDUSTRIAL PARK PROSPECT I I AC. INDUSTRIAL PARK Q N _ -4900- \ \ \ LOT7 I I� cc Lu J-Wo - - UD 1 1 UD \ x I'VDL SOSI'ECPIRK N UD _ U UD v� \ \ " O O 0 I I_ z z v 3 LEGEND - z Basin Summar Table Desi n Point Summar Table In O Q z z A BASIN DESIGNA11ON Basin Area 2 r Q 100 r Q Design Point Contributing Basins 2 r Q 100 r Q NORTH AMERICAN VERTICAL DATUM 1988 _ ckf NAVD88 & GEOID 18 NGS BENCHMARK: J BASIN AREA 84 6 EX 1 0.73 1 .8 7.3 1 OS 1 , OS2 2.9 12.7 ( ) O W IN ACRES AC so% PERCENT IMPERVIOUNSESS EX2 0.44 1 .2 4.4 2 OS7, EX1 , EX2 2.7 11 .8 CD X 402 V � O EX3 0.09 0.1 0.4 3 OS7 OS8 EX 1-EX4 3.8 17.1 ELEVATION=4890.87' zCD (� 1 DRAINAGE DESIGN POINT EX4 0.54 1 .1 4.9 4 OS3, EX7 3.6 14.1 - EX5 0.58 1 .0 4.9 5 OS4, OS5, EX6 1 .9 8.2 BASIS OF BEARING: W 5400 EXISTING MAJOR CONTOUR EX6 0.28 0.7 2.8 6 OS3-OS5, EX6, EX7 5.5 21 .5 COLORADO STATE PLANE COORDINATES NAD m 0 5400 EXISTING MINOR CONTOUR EX7 0.33 0.9 3.3 7 EX8, EX9 0.6 2.4 83(2011) DATUM. HORIZONTAL CONTROL X BASED UPON TRIMBLE VRS NOW NETWORK J - - - - - - - - - EX8 0.23 0.6 2.3 8 OS3-OS6, EX6-EX10 7.1 28.0 W EXISTING EASEMENT EX9 0.04 0.0 0.1 9 OS1 OS2, EX5 EX111 4.2 18.2 _ EX10 0.56 1 .1 4.9 EXISTING EDGE OF ASPHALT EXISTING DRAINAGE BASIN EX 11 0.23 0.6 2.3 OS1 1 .61 1 .6 6.9 EXISTING DRAINAGE FLOW ARROW OS2 1 .45 1 .3 5.9 EXISTING DRAINAGE SWALE OS3 1 .24 3.0 11 .2 sT EXISTING STORM SEWER OS4 0.54 1 .3 5.4 UD EXISTING UNDERDRAIN OS5 0.01 0.0 0.0 ❑ Fol Iu EXISTING STORM SEWER STRUCTURE OS6 0.01 0.0 0.0 SHEET OS7 0.02 0.0 0.1 OS8 0.02 0.0 1 0.1 30 0 30 60 N SCALE IN FEET 0 0 r m LAt CL - / 4897.86 E-X._._12=ffVC�TR - - \ \ I EX. 12" PVC STRM \ 48 7.26 EX1 EX5 EX COBBLE / E o \ I w . rn \ I DRAINAGE 4 9 / \ 0.73 $7�° I I EX. STRM INLET CHANNEL OAc. �$% 17.45 oA EX. METAL 4895 , DRAINAGE CHASE � \ I �0 o CN �? oN E �� _ EX. o 4898.15 ,,... � � EX. STRM If�LET - \ / 489 I o EX. STRM INLET EX. 12 PVC STRM 7.82 4898.47 D:.g \ 1 I I / \ / /� / 00 o T. °4899 - j i \ � \ = FO I x - 4�97.79 Z-- m w - I O N � C �� \ N J � o � EX. ,PGIETAL �, w 1 OS7 /- - Q - - - - - 1�� DRAINAGE _ SEX. CC o Q \ :- J \ �j{ 0.02 51% � � �\ � ASE � CH Nt` oo � EX. 10" PVC OUTFALL \ V Z EX. LOT�_? I I oS2 \ � �,, _� Z � O 4" PERF STRM _ PKOSPECr I I m � CC F- \ � l,'VDL/ST%KIAL PARK f \\ co Q 0 LOT2LL PROSPECT 1 LOT LINE, TYP. \ ` �\ 7- co _ a:1 � LOT6 � � / \ INDUSTRIAL PARK _ PROSPECT 1 CC V INDUSTRIAL PARK - \ / O Z O Z -4900- Q\ \ � Z o \'� \ zoo o IUD v UD -- U UD UD � \ LOTJ VIPONTATPROSPECT EX. STRM JUNCTION STRUCTURE \ � co PARA-EAST EX. TRENCH DRAIN EX. 4 PERF STRM I � I I Na / co 0 I O �O \ O O \ EX. 4" PERF STRM o N mo 0 o UD UD UD UD UD UD \ Y z p UD J O ros1 I000 \ LOT7 oc \ AC. PROSPECT - EX. 4 PERF STRM I I -INDUSTRIAL PARKUD UD #� UD UD 4DO X _ kL 1111Y i w u yam- u _ x X LOT22 PROSPECT - INDUSTRIAL PARK - LOT_0 PROSPECT PROSPECT PROSPECT LOT IN Z DIISTR14L PAR INDUSTRIAL PARK PARK INDUSTRIAL PARR PROSPECT PROSPECT INDUSTRIAL PARK INDUSTRIAL PARK 2 a. c� Q O 00 N = W N � 0 O O N J Q O Z LEGEND Basin Summary Table Design Point Summar Table BENCHMARK: Z Q w Basin Area 2 r Q 100 r Q Design Point ContributingBasins 2 r Q 100 r Qco Z ` A BASIN DESIGNA11ON NORTH AMERICAN VERTICAL DATUM 1988 EX1 0.73 1 .8 7.3 1 OS1 , OS2 2.9 12.7ckf - BASIN AREA 84.6 EX2 0.44 1 .2 4.4 2 OS7 EX1 EX2 2.7 11 .8 (NAVD88) & GEOID 18 NGS BENCHMARK: J W IN ACRES AC 80� PERCENT IMPERVIOUNSESS "X 402" O EX3 0.09 0.1 0.4 3 OS7, OS8, EX 1-EX4 3.8 17.1 () V CD ELEVATION=4890.87' CDEX4 0.54 1 .1 4.9 4 OS3, EX7 3.6 14.1 Z Q DRAINAGE DESIGN POINT EX5 0.58 1 .0 4.9 5 OS4, OS5, EX6 1 .9 8.2 BASIS OF BEARING: ckf EX6 0.28 0.7 2.8 6 OS3-OS5, EX6, EX7 5.5 21 .5 5400 COLORADO STATE PLANE COORDINATES NAD EXISTING MAJOR CONTOUR W 0 EX7 0.33 0.9 3.3 7 EX8, EX9 0.6 2.4 m 5400 EXISTING MINOR CONTOUR 83(2011) DATUM. HORIZONTAL CONTROL J X LL If EX8 0.23 0.6 2.3 8 OS3-OS6, EX6-EX10 7.1 28.0 BASED UPON TRIMBLE VRS NOW NETWORK W - - - - - - - - - EXISTING EASEMENT EX9 0.04 0.0 0.1 1 9 OS1 , OS2, EX5, EX11 4.2 1 18.2 EX 10 0.56 1 .1 4.9 EXISTING EDGE OF ASPHALT EX 11 0.23 0.6 2.3 E EXISTING DRAINAGE BASIN OS1 1 .61 1 .6 6.9 EXISTING DRAINAGE FLOW ARROW OS2 1 .45 1 .3 5.9 EXISTING DRAINAGE SWALE OS3 1 .24 3.0 11 .2 ST EXISTING STORM SEWER OS4 0.54 1 .3 5.4 N UD EXISTING UNDERDRAIN OS5 0.01 0.0 0.0 OS6 0.01 0.0 0.0 ❑ Fol Iu EXISTING STORM SEWER STRUCTURE OS7 0.02 0.0 0.1 SHEET OS8 0.02 0.0 1 0.1 30 0 30 602 N SCALE IN FEET 0 E 0 r m EX. 24" RCP W/ FES m EX. STRM INLET 0 w Y U W EX. 24" RCP W/ FES EX. 24" RCP W/ FES SHARP POINT DRIVE C3 0 OS8 =- \ \ w - - 4896 - 0AC. 2% o N EX. STRM INLET 0.02 2% \1 I I - - AC. N AC. �- RAIN GARDEN 1 0 I WQCV=4893.5 \ 2 0 - - - - - 9 i- - '---' w BOP=4892.5 Z 1-1WQCV=4 m BOP=4892.5 0 4897 �r I I ti I\ _4,' 0.01 2% N _ DRAINA E�ESMT / 4896" AU. LLJ I/A CD 3 L I I I I rEX4-A EX. STRM INLET ' 0.90 ss% /cn AC. 41UD r� I o.48 71% 1 4g93' / vyg ao rn " \ �� \�, 4895- W Z 1 / I t,,,p,, I I - I "� 1 4a94 -� I - EX CO BL�( I � '� � I - \ ' 12 STORM i EX. STRM STORM \ sT�89� � \ �LET - � � O _ 4896 1 DAINAE _ - I I I I I I - 4895 - - I _ � � Z0U C ANNE I ' / i �" - l._ I 1 �. - - - - - - - - I ��r Q Q O EX10-Aco X: 3 15% T O 0.2 ~ EX.4 ._ - 1 I `� /� i a.c, AREA INLET � � X. 3) 12" STRM o \ 1 ( - O o I O PER P T EXTERNAL ROOF O ^� co1 / � ��" ��• I ��. �/ EX. DRAINAGE '� I I � I I F�E=4897. 0' ' � ` � � � 1 � •, �� 0.04 2% I CO _ CHANNEL UNDER ' \ \ V WALKWAY 1 1 i / 1 \ EX. CONCRETE DRAINAGE AC. \ I _ EX2-A Q I CHANNEL UNDER WALKWAY EXISTING BUILDING EX. GRASS SWALE 0..4c so% 1825 SHARP POINT DRIVE I I I I EXISTING BUILDING � 1 LOTI = I I FFE=4897.30' I I I I 1901 SHARP POINT DRIVE II EX. ROOF DRAIN I N Lo a VrPo pITEROT ECT - I \ I I I FFE=4896.00 EX. 15' EX8 EX3 = EX. PERS PLAT T I I I I I ESMT PER I I 1 0 0 �� EXTERNAL ROOF DRAIN 1 I PLAT oAC. 90% i �o N 0.09 13% / / 1 1 I I I N I TOT 12 0 0 0 AC. ° EX. METAL DRAINAGE CHASE I I I I I EX. COBBLE IN U OSRIALPARK o w w m DRAINAGE Q = RIGHT-OF-WAY - I � _�• EX. (2) 12 STRM CHANNEL � �J LINE, TYP. \ - _ - _ - � - i I I / � 1 EX. 12" PVC STRM rEX7-A EX. 12" STRM EX. 12" STRM EX. STRM INLET a\ rn EX1-A \ \ l I 1 48951 EX. CONCRETE SIDEWALK CHASE - o.9s 80% v EX. STRM INLET �p9s / 4897 I r 0.33 91% -� DRAIN PAS / � ,,I l I 1 o AC. AC. I - METAL DRAINAGE CHASE -4895 �Ioo �\ ` I I X. ESM I I I I 1 I I PER PLAT ' )o DRAINAGE CHANNEL Q EX. STRM I LET' 1 I `, �� -- I 5 OS5 \ 0 ll-- g6 �� r X. RM INLE 4 ' \ EX. .12 PVC STRM DRAIN P N o� g5 0.01 2% W \ OS7-A � \ EX. STRM INLET, /A �h$ AC. \ \ e >( \ AC. `\ 1 ~ I I L / / 7/ / I INk 0.28 97% \ \ \ •. \ 1 I i w • / /� �` - /i EX. CONCRETE -4896 AC. � I \ \ � 4899 -� • _ - � _ ;EX. CONCRETE DRAINAGE \ (4) 4" PERF STRM � '- � ��'/ CH NNEL UNDER WALKWAY F ...... \ ...... ...... WWI\ �� ...... -UD ...... ...... ...... �'� _AGE PROPERTY LINE, TYP. EX. CODRAINAGE 1 11 CHANNELLNCRETE UNDER WALKWAY I / LOT3 I I OS2-A PROSPECT 1.45 \ � INDUSTRIAL PARK I I AC. f �\ � ) 0S3 1 I OS4 LOTH = LOT2 LOT LINE TYP. -}� - �\ 1.24 90% PROSPECT V O 1 PROSPECT LOT6 AC 0.54 90% INDUSTRIAL PARK INDUSTRIAL PARK I _ cl PROSPECT 1 1 I AC' 30 0 30 60 = Z 4900_ I 1 1 INDUSTRIAL PARK \ / Q CD _ - \ \ LOT7 0. • \� PROSPECT I I LOTIo SCALE IN FEET � W L \ PROSPECT o a O o I U p I U D i x INDUSTRIAL PARK INDUSTRIAL PARK N UD U UD I � \ \� � � I I_ Z CL � J a LEGEND O � O W C� J /4 BASIN DESIGNATION 5400 PROPOSED MAJOR CONTOUR Desi n Point Summar Table Basin Sum mar Table BENCHMARK: W co w BASIN AREA 5400 PROPOSED MINOR CONTOUR a _Z z 84.6 Basi n Area 2 r Q 100 r Q Design Point Contributing Basins 2 r Q 100 r Q PROJECT DATUM: NAVD88 Z J IN ACRES Ac 80% PERCENT IMPERVIOUNSESS - PROPOSED DRAINAGE BASIN 1 OS1-A, OS2-A, OS7-A 2.9 12.8 EX1-A 0.96 2.1 9.6 2 W J BENCHMARK 3-07 Q a 3 OS8, EX 1-A,EX2-A, EX3,EX4-A 4.2 18.8 EX2-A 0.44 1.2 4.4 # O PROPOSED DRAINAGE FLOW ARROW NORTHWEST CORNER OF TIMBERLINE RD. AND PROSPECT RD. ON THE O cli 1Q DRAINAGE DESIGN POINT 4 OS3, EX7-A 3.7 14.1 EX3 0.09 0.1 0.4 NORTHWEST CORNER OF A TRAFFIC SIGNAL BASE. V sT PROPOSED STORM SEWER 5 OS4, OSS, EX6 2.0 7.4 EX4-A 0.48 1.0 4.5 ELEVATION: 4919.13 UD PROPOSED UNDERDRAIN 6 OS3-OS5, EX6, EV A 5.7 21.5 EX6 0.28 0.7 2.8 ckf 5400 EXISTING MAJOR CONTOUR BENCHMARK # 4-07 7 EX8, EX9 0.7 2.4 EV A 0.33 0.8 3.3 SOUTHWEST CORNER OF TIMBERLINE RD. AND BEAR MOUNTAIN DR. DUE NORTH LLI O O 5400 - EXISTING MINOR CONTOUR 8 OS3-OS6, EX6-EX10-A, C2 7.1 27.3 EX8 0.23 0.6 2.3 OF NEW POLICE BUILDING ON THE SOUTHWEST CORNER OF A CATCH BASIN. m LL 9 OS1-A, OS2-A, OS7-A, C3 1 3.0 13.0 EX9 0.04 0.0 0.1 ELEVATION: 4942.84 EXISTING EASEMENT J - - - - - - - - EX10-A 0.23 0.2 0.8 PLEASE NOTE: THIS PLAN SET IS USING NAVD88 FOR A VERTICAL DATUM. EXISTING EDGE OF ASPHALT C2 0.90 1.6 6.9 SURROUNDING DEVELOPMENTS HAVE USED NGVD29 UNADJUSTED DATUM PRIOR C3 0.07 0.0 0.2 CITY OF FORT COLLINS DATUM) FOR THEIR VERTICAL DATUMS. EXISTING DRAINAGE BASIN OS1-A 1.61 1.6 6.9 �� EXISTING DRAINAGE FLOW ARROW OS2-A 1.45 1.3 5.9 IF NGVD29 UNADJUSTED DATUM (PRIOR CITY OF FORT COLLINS DATUM) IS E REQUIRED FOR ANY PURPOSE, THE FOLLOWING EQUATION SHOULD BE USED: ' EXISTING DRAINAGE SWALE OS3 1.24 3.0 11.2 NGVD29 UNADJUSTED DATUM (PRIOR CITY OF FORT COLLINS DATUM) = NAVD88 sT EXISTING STORM SEWER OS4 0.54 1.3 4.8 DATUM -3.18'. OS5 0.01 0.0 0.0 0 uD EXISTING UNDERDRAIN OS6 0.01 0.0 0.0 czD ❑ � Cq EXISTING STORM SEWER STRUCTURE OS7-A 0.02 0.0 0.1 BASIS OF BEARIN(x OS8 0.02 0.0 0.1 W ^ � EXISTING EMERGENCY OVERFLOW COLORADO STATE PLANE COORDINATES NAD 83(2011) DATUM. HORIZONTAL SHEET CONTROL BASED UPON TRIMBLE VRS NOW NETWORK 0 0 r m co X. 1 P_C T EX. 12" PVC STRM 0° I EX 1-A / Ld 1 Lo_ \ EX.1 STRM INLETs6' ` r = SIDEWALK CHASE o oAsos 80% o 0 0 0 / 4897 0 o I U / METAL DRAINAGE CHASE -4895- F w I DRAINAGE CHANNEL Al �p I I � � ° � o � EX. STRM If�LET �, N ,rn . I DRAIN P Aa9r0 �`�' oN OS7-A o EX. STRM INLET, EX. 12 .PVC STRM � / 0.0251% 0001F L \ \tI •` m o p CV s � OXBOW man-0 h / \ z o Ld o Q (4) 4" PERF STRM ; OS2-A \ _ / w Z PROSPECT \ ` •/ / O m w 0 \ / I INDUSTRIAL PARK I I 1 AC. 38% \� �- 0 O U LOT2 I a � awD ' LOT LINE, TYP. co 2 � 1 PROSPECT LOT 6 \ `� BOX INDUSTRIAL PARK I _ � PROSPECT � � \ � 1 0 � O (/� 4900_ I _ ! I I INDUSTRIAL PARK � - \ � / � Z O Z Z \ Z � H O o \ _ O V UD U UD UD UD co = LOT I I �\\ VIPONTATPROSPECTRK I \ PAEAST �' EX. TRENCH DRAIN EX. 4" PERF STRM I I I �,�`3 BOX. Lo r � I T � � � ""WO co I I I C� CD 00 CDN . I EX. 4" PERF STRM I I �o,�o o 0 o ' mo CD UD UDGj UD Uu UD �UD a o 00 � UD � J = _- �� ------- - LOT 7 n PROSPECT �c900i / OS♦1-A I 0 ` INDUSTR19L PARK Co as AC. EX. 4" PERF STRMUD UD I I 1 ERR D --RR� ... ERR 00 LOT22 r �- PROSPECT - INDUSTRIAL PARK LOT20 LOT21 PROSPECT LOT/9 LOT18 LOT 17 PROSPECT INDUSTRIAL PARK PROSPECT PROSPECT INDUSTRIAL PARK INDUSTRIAL PARK PROSPECT INDUSTRIAL PARK INDUSTRIAL PARK 2 30 0 30 60 Q SCALE IN FEET = Z Lu 0. O ON O N J N LEGEND � � � � O V � 0 W � Z J A BASIN DESIGNATION 5400 PROPOSED MAJOR CONTOUR O w co z BASIN AREA 846 5400 PROPOSED MINOR CONTOUR Design Point Summary Table Basin Summar Table BENCHMARK: Q Z IN ACRES AC 80% Desi n Point Contributin Basins 2 r Q 100 r Q Basin Area 2 r Q 100 r O w Z � J PERCENT IMPERVIOUNSESS - ' PROPOSED DRAINAGE BASIN ckf 1 OS1-A, OS2-A, OS7-A 2.9 12.8 EX1-A 0.96 2.1 9.6 PROJECT DATUM: NAVD88 0 Q J CD PROPOSED DRAINAGE FLOW ARROW 3 OS8, EX1-A,EX2-A, EX3,EX4-A 4.2 18.8 EX2-A 0.44 1.2 4.4 V 0 1Q DRAINAGE DESIGN POINT BENCHMARK # 3-07 4 OS3, EX7-A 3.7 14.1 EX3 0.09 0.1 0.4 NORTHWEST CORNER OF TIMBERLINE RD. AND PROSPECT RD. ON THE Q V sT PROPOSED STORM SEWER 5 OS4, OS5, EX6 2.0 7.4 EX4-A 0.48 1.0 4.5 NORTHWEST CORNER OF A TRAFFIC SIGNAL BASE. UD PROPOSED UNDERDRAIN ELEVATION: 4919.13 CC 5400 EXISTING MAJOR CONTOUR 6 OS3-OS5, EX6, EX7-A 5.7 21.5 EX6 0.28 0.7 2.8 w 0 5400 - EXISTING MINOR CONTOUR 7 EX8, EX9 0.7 2.4 EX7-A 0.33 0.8 3.3 BENCHMARK # 4-07 0 8 OS3-OS6, EX6-EX10-A, C2 7.1 27.3 EX8 0.23 0.6 2.3 SOUTHWEST CORNER OF TIMBERLINE RD. AND BEAR MOUNTAIN DR. DUE NORTH LL OF NEW POLICE BUILDING ON THE SOUTHWEST CORNER OF A CATCH BASIN. J - - - - - EXISTING EASEMENT 9 OS1-A, OS2-A, OS7-A, C3 3.0 13.0 EX9 0.04 0.0 0.1 ELEVATION: 4942.84 EX10-A 0.23 0.2 0.8 EXISTING EDGE OF ASPHALT C2 0.90 1.6 6.9 PLEASE NOTE: THIS PLAN SET IS USING NAVD88 FOR A VERTICAL DATUM. EXISTING DRAINAGE BASIN C3 0.07 0.0 0.2 SURROUNDING DEVELOPMENTS HAVE USED NGVD29 UNADJUSTED DATUM (PRIOR EXISTING DRAINAGE FLOW ARROW OS1-A 1.61 1.6 6.9 CITY OF FORT COLLINS DATUM) FOR THEIR VERTICAL DATUMS. OS2-A 1.45 1.3 5.9 IF NGVD29 UNADJUSTED DATUM (PRIOR CITY OF FORT COLLINS DATUM) IS EXISTING DRAINAGE SWALE OS3 1.24 3.0 11.2 REQUIRED FOR ANY PURPOSE, THE FOLLOWING EQUATION SHOULD BE USED: ST EXISTING STORM SEWER OS4 0.54 1.3 4.8 NGVD29 UNADJUSTED DATUM (PRIOR CITY OF FORT COLLINS DATUM) = NAVD88 J UD EXISTING UNDERDRAIN OS5 0.01 0.0 0.0 DATUM -3.18. N OS6 0.01 0.0 0.0 C"j ❑ Vol Cq EXISTING STORM SEWER STRUCTURE 0S7-A 0.02 0.0 0.1 BASIS OF BEARING: OS8 0.02 0.0 1 0.1 SHEET COLORADO STATE PLANE COORDINATES NAD 83(2011) DATUM. HORIZONTAL CONTROL BASED UPON TRIMBLE VRS NOW NETWORK 4 0 E O s