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Home My WebLink AboutHARMONY 23 - FDP - FDP170010 - SUBMITTAL DOCUMENTS - ROUND 1 - DRAINAGE REPORTProject Development Plan (PDP) Final Drainage Report for Harmony 23 submitted to: City of Fort Collins, Colorado March 1, 2017 748 Whalers Way Suite 200 Fort Collins, CO 80525 970.226.0557 main 970.226.0204 fax ideas@tstinc.com www.tstinc.com March 1, 2017 Mr. Dan Mogen, E.I., C.F.M. Development Review Engineer City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80521 Re: Project Development Plan (PDP) for H23 Project No. 1219.0002.00 Dear Mr. Mogen: We are pleased to submit this Final Drainage Report for Harmony 23 (H23). This report analyzes the developed stormwater runoff from the project and provides stormwater infrastructure and water quality management for runoff. This report has been prepared based on the City of Fort Collins Stormwater Criteria Manual and complies with the PDP submittal requirements for a final drainage report. Respectfully, TST, INC. CONSULTING ENGINEERS Derek A. Patterson, P.E. Jon Sweet, P.E. DAP/JFS/jrm Harmony 23 Final Drainage Report TABLE OF CONTENTS Page 1.0 Introduction 1.1 Scope and Purpose ..................................................................................................... 1 1.2 Project Location and Description ................................................................................. 1 1.3 Previous Studies ......................................................................................................... 3 1.4 Limitations of Future Projections ................................................................................. 3 2.0 Historic/Existing Conditions ......................................................................................... 4 3.0 Developed Conditions Plan 3.1 Design Criteria for Hydrologic Analysis ....................................................................... 6 3.2 Drainage Plan Development ....................................................................................... 7 3.2.1 Street Capacity ................................................................................................. 10 3.2.2 Inlet Design ...................................................................................................... 10 3.2.3 Storm Sewer Design ........................................................................................ 10 3.2.4 Channel Design ................................................................................................ 11 3.2.5 Riprap Design ................................................................................................... 11 3.2.6 Detention Pond Design .................................................................................... 11 3.3 Low Impact Development .......................................................................................... 13 3.4 Floodplain Management ............................................................................................ 14 4.0 Conclusion ....................................................................................................................... 14 5.0 References ....................................................................................................................... 16 Figures Figure 1. Vicinity Map ................................................................................................................... 2 Figure 2. Outfall to the Poudre River ............................................................................................ 5 Appendices Appendix A: Rational Method Hydrologic Analysis Appendix B: Street Capacity and Inlet Analysis Appendix C: Storm Sewer Design Appendix D: Channel Design Appendix E: Riprap Design Appendix F: Detention Pond Design Appendix G: FIRM Maps and Original Floodplain Workmap Appendix H: Excerpts from Reference Reports Appendix I: Proposed Drainage Maps Harmony 23 Final Drainage Report Page 1 1.0 Introduction 1.1 Scope and Purpose This report presents the results of a final drainage analysis for the Harmony 23 (H23) project. This report has been developed in accordance with the City of Fort Collins Stormwater Criteria Manual requirements and complies with Project Development Plan (PDP) submittal requirements. 1.2 Project Location and Description The H23 project is a multifamily development situated on approximately 25 acres. The project is located in the northeast corner of Section 4, Township 6 North, Range 68 West, more specifically at the southwest corner of the intersection of Harmony Road and Strauss Cabin Road. The site is generally bounded by the following roadways: Strauss Cabin Road on the east, Harmony Road on the north, and the Fossil Creek Reservoir Inlet Ditch (FCRID) along the south and west. Surrounding properties include: The Arapaho Bend Natural Area on the north side of Harmony Road, the Harmony & Strauss Cabin Convenience Shopping Center Subdivision (development recently approved, but is now being reconsidered/redesigned by that developer) to the east of Strauss Cabin Road, Brookfield Subdivision to the southwest, and undeveloped land to the west. The Boxelder Ditch cuts through the site starting north at Harmony Road and running south through the middle of the site where it crosses Strauss Cabin Road approximately 1600’ south of Harmony Road. This development is located within the Cache la Poudre watershed and City of Fort Collins Poudre River drainage basin. This project site sits just west of the FEMA regulated floodway but within the 500-yr floodplain, per FEMA FIRM Maps 08069C0994F LOMR dated December 15, 2014. The floodplain and floodways lines are shown in Figure 1 on the next page. Harmony 23 Final Drainage Report Page 2 Figure 1. Vicinity Map Harmony 23 Final Drainage Report Page 3 1.3 Previous Studies  WEITZEL POND #1 Drainage Report for Harmony & Strauss Cabin  ODP Drainage Report for Harmony & Strauss Cabin  Harmony & Strauss Cabin Subdivision Filing No. 1 Convenience Shopping Center PDP Final Drainage Report  North I-25 EIS, August 2011  Poudre River Drainage Basin Master Plan 1.4 Limitations of Future Projections The analysis and proposed stormwater improvements contained in this study are for the H23 project area. Assumptions have been made to account for future development adjacent to the site where developed flows and storm infrastructure from this project will influence future designs. In addition, assumptions were made to account for interim and ultimate tail water conditions downstream of this site. It is assumed that the outfall from the H23 site will connect to a future stormwater system, which will ultimately daylight into a regional detention facility for the 266-acre Harmony and I-25 development. This regional detention facility is also assumed to be a non-potable irrigation pond. The final/ultimate water surface elevation in this future regional detention pond will need to be designed to not affect upstream developments. A master plan for the Harmony and I-25 development is in progress, but has not been completed at the time of this report. The grading and drainage plan provided herein assumes that the WEITZEL POND #1 project has progressed and has filled the portion of the Existing Gravel Pond #1 shown in the WEITZEL POND #1 plans. However, there will be no negative impacts to the H23 site if that project has not been completed before H23 is complete. In addition, this report also assumes that the Convenience Shopping Center will be constructed at some point in the future and that the Box Elder Ditch will be realigned through the site prior to H23 construction. It is also assumed that even though the Convenient Shopping Center is being redesigned, that the drainage design and impacts will be very similar to what is currently designed for that project. Therefore, the design and assumptions made with that project will continue to be used for this project. For this project the downstream interim 100-yr WSEL in the interim regional detention pond (Ex. Gravel Pond #1) is assumed to be a 4838.59, per the Convenience Shopping Center report. This tailwater elevation was assumed to be the worst case scenario, and was used for the H23 design and calculations. The ultimate/final water surface elevation in the regional detention pond is assumed to be equal to or lower than this elevation. Harmony 23 Final Drainage Report Page 4 Stream stability analysis, open water and wetlands mitigation are beyond the scope of this report and will be addressed separately or in a subsequent design report. 2.0 Historic/Existing Conditions Historically this area was undeveloped grasslands, that was eventually utilized for farming. The Boxelder Ditch which runs through the site was used for irrigation purposes. Today, this site is no longer used for farming and has returned back to undeveloped grasslands. The site generally slopes from the west to the east to the low point in Strauss Cabin Road. Slopes vary from 1:1 on the west end to basically flat on the east. According to the Natural Resources Conservation Service (NRCS) the project site is characterized by Type A, B and D soils. The NRCS soils data for this site can be found in the Appendix The historic stormwater runoff rate from this site is based on the calculations provided in the Convenience Shopping Center report, which was determined to be 0.165 cfs/acre (27.2 acres / 4.5 cfs). There are currently a small amount wetlands, approximately 411 s.f., located on the project site. As stated previously wetlands will be addressed separately in a subsequent design report if required. Harmony 23 Final Drainage Report Page 5 Figure 2. Outfall to the Poudre River Harmony 23 Final Drainage Report Page 6 3.0 Developed Conditions Plan 3.1 Design Criteria for Hydrologic Analysis The drainage plan presented in this report has been developed in accordance with the City of Fort Collins Stormwater Criteria Manual and the City of Fort Collins submittal requirements for a Project Development Plan (PDP). The drainage plan presented is based upon the allowable developed stormwater release rates prescribed for the Poudre River drainage basin, that being the 2-year historic rate. The drainage basin presented in this report is less than 90 acres, therefore, the method used to analyze drainage for this project will be the Rational Method. Runoff calculations for both the 2-year and 100-year storms will be presented here. The Rational Method is given by: Q = C(Cf)IA where  Q is the maximum rate of runoff in cfs  C is the runoff coefficient  Cf is the runoff coefficient frequency factor adjustment  I is the rainfall intensity in inches per hour for a storm duration equal to the time of concentration  A is the total area of the basin in acres The runoff coefficient C has different values depending on the design storm recurrence interval. The runoff coefficient is also dependent on land use or surface characteristics/imperviousness. Runoff coefficients were assigned using Table RO-11 from the Fort Collins Stormwater Criteria Manual. The frequency factor adjustment, Cf, varies depending on the storm frequency and can be found in Table RO-12 of the Fort Collins Stormwater Criteria Manual. The rainfall intensity is selected from Rainfall Intensity Duration Frequency Curves for the City of Fort Collins (Tables RA-7 through RA-9 of the Fort Collins Stormwater Criteria Manual). In order to utilize the Rainfall Intensity Duration Curves, the time of concentration is required. The following equation is used to determine the time of concentration tc = ti + tt where  tc is the time of concentration in minutes  ti is the initial or overland flow time in minutes Harmony 23 Final Drainage Report Page 7  tt is the conveyance travel time in minutes The initial or overland flow time is calculated with the UDFCD equation:  0.33 f i S t 1.87 1.1 * C D  C  For design points requiring attenuation, the total area and area weighted average percent impervious were calculated. The time of concentration for the combined basins was assumed to be the maximum time of concentration for any individual basin. This time of concentration was used to obtain a rainfall intensity, which was multiplied by the composite runoff coefficient and total area to obtain an attenuated flow. 3.2 Drainage Plan Development The H23 project is proposed to be a multifamily site accompanied by parking areas, open space, and public roadway improvements. The site and associated storm sewer system has been designed to collect and convey a majority runoff from this project, including portions of the fronting ½ of the surrounding public roadways to the two separate ponds located onsite. Due to design constraints, a small portion of runoff from the project site will be collected and conveyed to an offsite detention pond where it will be detained and released. Drainage to this offsite pond has been approved by both the adjacent developer and the City. For design calculations, the site was divided into several basins. All basins are further described below. Basin N-1, as shown on the Drainage Plan, is in the northern portion of the project site which includes open space, parking areas and building footprints. Runoff from this basin is conveyed via curb & gutter into the storm sewer system which drains into to Pond A. Basin N-2 is the northern most portion of the project site which includes open space, trails, and building footprints. Runoff from this basin is conveyed via grass swale into under sidewalk chases and into a storm culvert which drains into to Pond A. The basin includes Pond A. Basin N-3 is in the northern portion of the project site which includes open space, parking areas and building footprints. Runoff from this basin is conveyed via curb & gutter into the storm sewer system which drains into to Pond A. Basin N-4 is in the northwest portion of the project site which includes open space, parking areas and building footprints. This basin drains to a curb cut and into Basin N-2. Ultimately Harmony 23 Final Drainage Report Page 8 runoff from this basin is conveyed to Pond A. Basin N-5 is in the north half of the project site which includes open space and building footprints. This basin drains to several area inlets where it is ultimately conveyed via proposed storm sewer system and into Pond A. Basin S-1 is in the southern portion of the project site which includes open space, parking areas and building footprints. Runoff from this basin is conveyed via curb & gutter into the storm sewer system which drains into Pond B. Basin S-2 is in the southern portion of the project site which includes open space, parking areas and building footprints. Runoff from this basin is conveyed via curb & gutter into the storm sewer system which drains into Pond B. Basin S-3 is in the southern portion of the project site which includes open space, parking areas and building footprints. Runoff from this basin is conveyed via curb & gutter into the storm sewer system which drains into Pond B. Basin S-4 is the southern portion of the project site which includes open space, trails and building footprints. Runoff from this basin is conveyed via swale or sheet flow directly into Pond B, or into the storm sewer system which drains into Pond B. This basin includes the extents of Pond B. Basin S-5 incorporates the southern fronting portion of Strauss Cabin Road to the back of the detached sidewalk. Runoff from this basin is conveyed via curb & gutter to a low point in Strauss Cabin Road where it is conveyed via the proposed storm sewer system and into Pond B. Basin S-6 includes a small portion of the south half of the site. Runoff from this basin is conveyed to a couple of area inlets then via the proposed storm sewer system and into Pond B. Basin U-1 incorporates fronting portions of Harmony Road and Strauss Cabin Road in addition to a portion of the project site. Runoff from this basin is conveyed via curb & gutter to a low point in Strauss Cabin Road north of a future drive access, where it is conveyed via the proposed storm sewer system south to the offsite ponds designed with the Convenience Shopping Center Report. All storage for this basin will be handled in the offsite ponds. Basin U-2 incorporates the middle fronting portion Strauss Cabin Road in addition to a portion of the project site. Runoff from this basin is conveyed via curb & gutter to another low point in Strauss Cabin Road just south of the future drive access, where it is conveyed via the proposed storm sewer system south to the offsite ponds designed with the Convenience Shopping Center Harmony 23 Final Drainage Report Page 9 Report. All storage for this basin will be handled in the offsite ponds. Basin U-3 incorporates the small area which drains to the curb cut located at the northern drive entrance for the project. Runoff from this basin is conveyed via curb & gutter to the curb cut and into Strauss Cabin Road, where it is conveyed via the proposed storm sewer system south to the offsite ponds designed with the Convenience Shopping Center Report. All storage for this basin will be handled in the offsite ponds. The 100-yr runoff volume and WQCV for all “N” basins will be detained in Pond A, while all runoff and WQCV for all “S” basins will be detained in Pond B. The 100-yr runoff volume for all “U” basins will be detained in the existing gravel ponds located offsite. Additional offsite basins contributing to the H23 drainage design are described below. Basin CSC-1 is an offsite basin contributing to the proposed storm sewer system located in Strauss Cabin Road. This basin is a portion of the Convenience Shopping Center Basin N-2, which has been subdivided with this project. Runoff from Basin CSC-1 will drain to a low point on Strauss Cabin Road where it will be conveyed via the proposed storm sewer system designed with the H23 project and into the existing gravel ponds. Detention and water quality from this basin have already been accounted for in the Convenience Shopping Center Final Drainage Report. Basin CSC- is an offsite basin contributing to the proposed storm sewer system located in Strauss Cabin Road. This basin is a portion of the Convenience Shopping Center Basin N-2 and N-16. Runoff from Basin CSC-2 will drain to a low point on Strauss Cabin Road where it will be conveyed via the proposed storm sewer system designed with the H23 project and into the existing gravel ponds. Detention and water quality from this basin have already been accounted for in the Convenience Shopping Center Final Drainage Report. Basins O-1 through O-8 are offsite basins that will pass through the site. No water quality or detention will be provided for these basins as they are not part of the subject property. Basins O-1 through O-7 are the areas between the FCRID and the property boundary which consists of gravel access road and undeveloped open space. Runoff from Basins O-1 through O-3 will be routed through Pond A, and runoff from Basins O-4 through O-7 will be routed through Pond B. Basin O-8 is the area just south of the project which consists of a small portion of undeveloped open space and a portion of Strauss Cabin Road. Runoff from this basin is conveyed via curb & gutter to a low point in Strauss Cabin Road where it will be routed through Pond B. Harmony 23 Final Drainage Report Page 10 3.2.1 Street Capacity Street capacities have been analyzed using the Urban Drainage UD-Inlet spreadsheet, version 4.01. Street capacity was analyzed along Strauss Cabin Road on the west side where ultimate roadway improvements are proposed between Harmony Road and the south end of this project. Table ST-2 and ST-3 in the City of Fort Collins Stormwater Criteria Manual state inundation standards for the minor and major storms. These standards are summarized in the table below. Table 1. Street ID Street Classification Minor Storm (2-yr) requirements Major Storm (100-yr) requirements Strauss Cabin Road 2-Lane Arterial No curb-overtopping, flow spread must leave at least 12’ wide travel path in each direction Depth of water must not exceed bottom of median gutter, 12” max depth at gutter flowline, flow must be contained within ROW. For this project street capacity for Strauss Cabin Road was analyzed. It was determined the streets meet the applicable requirements and will function below the allowed capacities. The results of the street capacity analysis can be found with supporting calculations in Appendix B. 3.2.2 Inlet Design Inlets have been analyzed using the Urban Drainage UD-Inlet spreadsheet, version 4.01. CDOT Type R inlets are proposed to collect runoff and have been placed at the low points of the basins where infall, vertical curb & gutter is located and have been analyzed for a “sump” condition. In addition area inlets have been placed within the open space throughout the project site. Sizing of these inlets is based on the capacity curves provided by the manufacture of those inlets. A majority of the inlets have been sized to capture the 100-yr storm. However, some inlets due location and site constraints have been sized to carry the 10-yr event, with the 100-yr storm overtopping and spilling directly into the ponds. The results of the inlet analysis are provided in Appendix B. 3.2.3 Storm Sewer Design Storm sewer pipes have been analyzed using UDSEWER 2009, version 1.4. All storm pipes on Harmony 23 Final Drainage Report Page 11 this project site are designed to collect and convey the 100-yr storm runoff. The pipes have all been sized to ensure that the hydraulic grade lines remain below the flowline elevation at inlets and below rim elevations at manholes. The results of the storm sewer analysis are provided in Appendix C. 3.2.4 Channel Design Proposed curb cuts and swales at this project site have been analyzed using Hydroflow Express Extension for Autodesk Civil3D. Swales have been designed to include 1’ of freeboard above the normal 100-yr water depth in the channel. Where the 1’ criteria isn’t possible, the swales have been checked to make sure they can pass at least 133% of design flow. All curb cuts have been sized to convey the 100-yr event. The results of the channel design are provided in Appendix D. 3.2.5 Riprap Design Riprap has been proposed at all outlet pipes into the ponds. Riprap has been sized based on equations and figures provided in the Urban Drainage manual. Although the ST-01C pipe outlet will discharge directly into groundwater filled pond, and the pipe outlet is anticipated to be underwater during an average day scenario, the groundwater in that pond may be lowered at any given time due to future construction activities at this site, so riprap has been proposed in this area as a ground stabilization measure. The results of riprap sizing are provided in Appendix E. 3.2.6 Detention Pond Design The existing conditions for this area was analyzed with the Convenience Shopping Center report to determine the allowable release rate from the site. The 2-yr historic discharge for this area was determined to be 4.50 cfs for the 27.2 acres estimated in that report. This ends up being a release rate of approximately 0.165 cfs/acre (4.5/27.2) which is the allowable release rate used in this report. There will be two ponds utilized on this site for water quality and detention. Pond A on the northeast end of the site and Pond B on the south end of the site. Both are designed to treat and release the WQCV, and have been designed using a 40 hour drain time. Both ponds have been sized to capture and release the 100-yr developed runoff at the 2-yr historic rate. In addition, due to high groundwater levels, Pond A will be lined to prevent groundwater from being exposed and a portion of Pond A will be utilized for wetland mitigation. Harmony 23 Final Drainage Report Page 12 The Ex. Gravel Pond #2 in the Convenience Shopping Center Report will be utilized to detain the 100-yr runoff from Basins U-1, U-2 and U-3. Per conversations with the City stormwater staff, the existing gravel ponds can be used as a water quality feature. Therefore, the WQCV for these basins was not added into the total required volume being detained offsite in Ex. Gravel Pond #2. The UDFCD manual and equations were used to calculate the WQCV. Pond A is sized to collect the WQCV for all N basins, and Pond B is sized to collect the WQCV for all S basins. The WQCV is designed to be released in 40-hr as recommend by UDFCD. A mass-balance spreadsheet was used to calculate the overall 100-yr detention requirements for this site. The required 100-yr detention volumes for Pond A and Pond B calculated from this spreadsheet were determined to be 1.89 acre-feet, and 2.17 acre-feet respectively. An additional 20% was added to these volumes, per City Criteria, resulting in a total 100-yr volume of 2.27 acre-feet for Pond A and 2.60 acre-feet for Pond B. The total volume required in the ponds based on City Criteria is the 100-yr plus the WQCV. Therefore, the required total volume was determined to be 2.45 acre-feet for Pond A and 2.80 acre-feet for Pond B. The results for these ponds are provided in Table 2. Table 2. Pond ID Contri- buting Area (acres) 2-yr Historic Release Rate (0.165 cfs/acre) 100-yr Detention Volume (120%) (ac-ft) Required WQCV (ac-ft) Total Required Storage (ac-ft) Total Provided Storage (ac-ft) 100-yr Water Surface Elevatio n Pond A 9.76 1.61 2.27 0.18 2.45 2.53 4848.00 Pond B 11.52 1.90 2.60 0.20 2.80 3.46 4846.00 Total Required 4.87 0.38 5.25 5.99 A mass-balance spreadsheet was used to calculate the overall 100-yr detention requirement for Basins U-1, U-2 and U-3. The required 100-yr detention volume from these basins was calculated to be 1.25 ac-ft. An additional 20% was added to the volume for a total volume of Harmony 23 Final Drainage Report Page 13 Shopping Center report will need to be modified. To simplify the design, the 9.0 cfs release rate from the spillway structure will be maintained and both the 2-yr spillway crest (Ex. Elev.=4837.39) and the 100-yr spillway crest (Ex. Elev.=4837.64) will be raised 0.10 feet each. Because this pond is situated within the floodway, a no-rise analysis, previously completed with the Convenience Shopping Center Report, will be updated and provided with final design. The undeveloped areas adjacent to the site denoted as O-1 through O-8 will release undetained through the site. This amount will be treated as a pass-through flow. The resulting amount of stormwater (100-yr) passing from Pond A will be approximately 1.1 cfs and 8.6 cfs for Pond B. The total 100-yr release from these undeveloped areas amounts to approximately 9.7 cfs. There will be 2 separate outlet structures utilized in Pond A, a water quality outlet structure to treat the water prior to entering the mitigated wetlands and a 2-stage outlet structure that will include the 100-yr detention volume and emergency overflow. The outlet structure for Pond B will consist of 3 stages. A WQCV stage (40-hr drain time), detention volume (2-yr historic release), and emergency overflow. An emergency overflow stage was added to both outlet structures due to site constraints discussed below. All ponds will have a minimum 1’ of freeboard above the detention surface elevation. In addition, due to high groundwater elevations, Pond A will be lined with either bentonite or some type of geotextile to prevent exposure of groundwater. The ponds for this site were located in areas to maximize developable area. Emergency spillways for each pond have not been provided due to site constraints. Therefore, these ponds don’t have a defined spillway. Instead Pond A is designed to pass a portion of the emergency flow through the 100-yr overflow stage on the outlet structure. Any runoff which exceeds the overflow capacity will pond up to the Boxelder Ditch (Elevation=4849.20) located along the east side of this pond, where it will ultimately either spill into and or across this ditch to the low point in Strauss Cabin Road. The difference between the detention surface elevation (4838.00) of Pond A and the Boxelder Ditch is approximately 1.20’. Similar to Pond A, Pond B will also have an emergency overflow stage on the outlet structure. However, this outlet structure and outlet pipe will be sized to convey the 100-yr storm event. In the event that the outlet pipe becomes clogged, runoff would back up into the parking lot and around Bldg. G, until it can spill across the Box Elder Ditch and into Strauss Cabin Road. This elevation is approximately 4849.50. All buildings within this area will be designed at an elevation higher than the spill elevation to prevent flooding. 3.3 Low Impact Development Per agreements with the City and adjacent property owner, all LID requirements for this project will be handled offsite on the property to the east with future development and will not be Harmony 23 Final Drainage Report Page 14 required at this time. 3.4 Floodplain Management This site is situated outside of any City of Fort Collins regulatory floodways and floodplains. This project site sits within the FEMA FIRM Map 08069C0994F dated December 19, 2006. The new LOMR (Case # 14-08-0580P, effective date 12-15-2014) that just received FEMA approval corrected the floodway and floodplain lines to align with the original floodplain workmap. Information provided in this LOMR was taken into consideration for this project. More specifically, flood zone designations within this project site per the LOMR are as follows:  Flood Zone X, Shaded 500-YEAR FLOODPLAIN: Areas of 0.2% annual chance flood hazard. Areas of 1% annual chance flood with average depth less than one foot or with drainage areas of less than one square mile.  Flood Zone X, Unshaded: Areas determined to be outside the 0.2% annual chance floodplain. Chapter 10, Flood Prevention and Protection, of the Fort Collins Municipal Code provided guidance and limitations for building and development within the floodway and floodplain. Division 4 – Poudre River Flood Hazard Areas of this chapter provide specific standards for development within the Poudre River floodway and flood fringe. The “Limits of Development” as shown on the Grading and Drainage Plan are outside of the half-foot floodway. However, we recognize that a majority of this area still resides within the 500-year floodplain. Land uses proposed within the “Limits of Development” do not include any critical facilities, essential service critical facilities, hazardous materials facilities, government services, or at risk population facilities. All structures planned to be built within the “Limits of Development” will be elevated and flood-proofed 2 feet above the 100-year flood elevations (shown as Base Flood elevations on the FIRM maps.) Ex. Gravel Pond #2 pond is situated within the floodway, a no-rise analysis, previously completed with the Convenience Shopping Center Report, will be updated and provided with final design. 4.0 Conclusion The City of Fort Collins Stormwater Criteria Manual has been used to establish the criteria for a developed condition runoff plan within the H23 project. This PDP drainage design report has highlighted the following items:  Project site development is outside of the effective floodway boundary, but within the 500-yr Harmony 23 Final Drainage Report Page 15 floodplain.  LID techniques are planned to be implemented offsite with future development, but are not required at this time.  Water quality and stormwater detention for the project will be provided in two separate ponds located onsite. These ponds have been sized to release the 100-yr storm at the 2-yr historic release.  A small portion of this project will be detained offsite in Ex. Gravel Pond #2 located east of the project.  All storm infrastructure has been sized to collect and convey at a minimum the 10-yr storm event. Harmony 23 Final Drainage Report Page 16 5.0 References 1. City of Fort Collins Stormwater Criteria Manual, Amendments to the Urban Drainage and Flood Control District Criteria Manual, Adopted December 2011, Last Revision April 2012. 2. Urban Drainage and Flood Control District Criteria Manual, Volume 3, August 2011 3. Federal Emergency Management Agency, 2006, Flood Insurance Rate Map, Larimer County, Colorado, Map Number 08069C0994F 4. Federal Emergency Management Agency, 2006, Flood Insurance Rate Map, Larimer County, Colorado, Map Number 08069C1013F 5. Natural Resources Conservation Services, 2013, Web Soil Survey: Soil Survey Area Larimer County Area, Version 8, Dec 23, 2013 6. Colorado Division of Reclamation, Mining & Safety website, http://mining.state.co.us/Pages/Home.aspx 7. Chapter 10 of the Fort Collins Municipal Code, http://colocode.com/fcmunihtml.html 8. LOMR, Case #14-08-0580P, Letter of Map Revision (LOMR-BD) Based on Better Data on the Cache la Poudre River I-25 Divided Flow Path Southwest of Harmony Road and Interstate 25, Anderson Consulting Engineers, Effective Date December 15, 2014. 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(2-yr) Power (100-yr) Appendix A H23 Final Drainage Report City of Fort Collins Rational Method Runoff Coefficients Lawn, Heavy, <2% Slope 0.20 Lawn, Heavy, >7% Slope 0.35 Lawn, Heavy, 2-7% Slope 0.25 Lawn, Sandy, <2% Slope 0.10 Lawn, Sandy, >7% Slope 0.20 Lawn, Sandy, 2-7% Slope 0.15 Roofs 0.95 Streets: Permeable Pavers 0.30 Streets: Gravel 0.50 Streets: Paved 0.95 From Table 3-3 of the City of Fort Collins, Stormwater Criteria Runoff Coefficient Appendix A H23 Final Drainage Report C2 C10 C100 Streets: Paved 1.79 0.95 Lawn, Heavy, <2% Slope 0.66 0.20 Roofs 0.82 0.95 Streets: Paved 0.20 0.95 Lawn, Heavy, <2% Slope 2.40 0.20 Roofs 0.33 0.95 Streets: Paved 0.85 0.95 Lawn, Heavy, <2% Slope 0.18 0.20 Roofs 0.47 0.95 Streets: Paved 0.23 0.95 Lawn, Heavy, <2% Slope 0.25 0.20 Roofs 0.04 0.95 Streets: Paved 0.31 0.95 Lawn, Heavy, <2% Slope 0.84 0.20 Roofs 0.39 0.95 Total N Basins 9.76 Total % Imp. 54.4% Avg. 100-yr C100 = 0.76 Streets: Paved 2.54 0.95 Lawn, Heavy, <2% Slope 1.40 0.20 Roofs 1.01 0.95 Streets: Paved 0.46 0.95 Lawn, Heavy, <2% Slope 0.47 0.20 Roofs 0.23 0.95 Streets: Paved 0.61 0.95 Lawn, Heavy, <2% Slope 0.21 0.20 Roofs 0.25 0.95 Streets: Paved 0.14 0.95 Lawn, Heavy, <2% Slope 2.65 0.20 Roofs 0.00 0.95 Streets: Paved 0.57 0.95 Lawn, Heavy, <2% Slope 0.53 0.20 Roofs 0.10 0.95 Streets: Paved 0.04 0.95 Lawn, Heavy, <2% Slope 0.24 0.20 Roofs 0.07 0.95 Total S Basins 11.52 51.8% Avg. 100-yr C100 = 0.74 Streets: Paved 1.54 0.95 Lawn, Heavy, <2% Slope 0.50 0.20 Roofs 0.05 0.95 Streets: Paved 1.44 0.95 Lawn, Heavy, <2% Slope 1.50 0.20 Roofs 0.54 0.95 Streets: Paved 0.07 0.95 Lawn, Heavy, <2% Slope 0.05 0.20 Roofs 0.00 0.95 Total U Basins 5.69 63.7% Avg. 100-yr C100 = 0.85 Total 26.97 Total % Imp. 55.2% Avg. 100-yr C100 = 0.77 *Percent Impervious Values based on UDFCD Vol 1., Chapter 6, Table 6-3 0.80 S-5 1.20 U-3 0.12 59.2% 0.64 0.64 0.64 0.62 0.62 1.00 S-4 2.79 6.9% 0.24 0.24 0.77 S-3 1.07 78.4% 0.80 0.80 0.80 N-4 0.52 52.1% 0.59 0.59 0.59 N-3 1.50 85.1% 0.86 0.86 0.86 N-2 2.93 18.6% 0.34 0.34 0.34 H23 Final Drainage Report C2 C10 C100 Streets: Paved 0.71 0.95 Lawn, Heavy, <2% Slope 0.22 0.20 Roofs 0.05 0.95 Streets: Paved 1.64 0.95 Lawn, Heavy, <2% Slope 1.06 0.20 Roofs 0.36 0.95 O-1 0.16 Lawn, Heavy, <2% Slope 0.16 0.20 20.0% 0.20 0.20 0.20 0.25 O-2 0.09 Lawn, Heavy, <2% Slope 0.09 0.20 20.0% 0.20 0.20 0.20 0.25 O-3 0.19 Lawn, Heavy, <2% Slope 0.19 0.20 20.0% 0.20 0.20 0.20 0.25 O-4 0.43 Lawn, Heavy, <2% Slope 0.43 0.20 20.0% 0.20 0.20 0.20 0.25 O-5 0.38 Lawn, Heavy, <2% Slope 0.38 0.20 20.0% 0.20 0.20 0.20 0.25 O-6 0.31 Lawn, Heavy, <2% Slope 0.31 0.20 20.0% 0.20 0.20 0.20 0.25 O-7 0.78 Lawn, Heavy, <2% Slope 0.78 0.20 20.0% 0.20 0.20 0.20 0.25 Streets: Paved 0.28 0.95 Lawn, Heavy, <2% Slope 0.24 0.20 Roofs 0.00 0.95 *Percent Impervious Values based on UDFCD Vol 1., Chapter 6, Table 6-3 Rational Method Frequency Adjustment Factors Min year Max year Frequency Factor, Cf 210 1 11 25 1.1 26 50 1.2 51 100 1.25 From Table 3-4 in the City of Fort Collins, SDDCCS O-8 0.52 54.8% 0.60 0.60 0.60 0.75 Frequency Adjusted Runoff Coefficients (C*Cf) Table A-1b Offsite Basin Composite Runoff Coefficients CSC-1 0.98 77.5% 0.78 0.78 0.78 0.98 Area (ac) Attribute Attribute Area (ac) Runoff Coefficient, C Percent Impervious Composite C 0.86 Basin/ Sub- Basin CSC-2 3.06 64.9% 0.69 0.69 0.69 Appendix A H23 Final Drainage Report Overland Flow Average Channelized Channel Channel Channelized Length, D Overland Slope Tov Tov Tov Flow Length Slope Velocity Time (Tt) (ft) (%) 2-year 10-year 100-year (ft) (%) (ft/s) (min) 2-year 10-year 100-year N-1 0.80 0.80 1.00 195 2 6 6 2 520 1.6 2.5 3.5 9 9 5 N-2 0.34 0.34 0.42 55 2 8 8 7 758 2.2 2.9 4.4 12 12 11 N-3 0.86 0.86 1.00 106 2 4 4 2 530 1.4 2.4 3.7 8 8 6 N-4 0.59 0.59 0.74 106 2 8 8 6 53 0.6 1.4 0.6 9 9 7 N-5 0.54 0.54 0.68 185 3.5 9 9 7 74 0.5 1.3 0.9 10 10 8 S-1 0.74 0.74 0.92 60 8 3 3 1 936 1.0 2.0 7.8 11 11 9 S-2 0.65 0.65 0.81 90 14 3 3 2 404 0.8 1.8 3.7 7 7 6 S-3 0.80 0.80 1.00 72 2 4 4 1 206 0.8 1.8 1.9 6 6 5 S-4 0.24 0.24 0.30 148 5.5 11 11 10 270 0.5 1.3 3.5 14 14 13 S-5 0.62 0.62 0.77 26 2 4 4 2 630 2.2 2.9 3.6 8 8 6 S-6 0.44 0.44 0.54 40 2 6 6 5 104 0.5 1.3 1.3 7 7 6 U-1 0.77 0.77 0.96 66 2 4 4 2 430 0.9 1.8 4.0 8 8 6 U-2 0.63 0.63 0.78 110 2 7 7 5 442 0.6 1.4 5.3 12 12 10 U-3 0.64 0.64 0.80 40 2 4 4 3 72 3.4 3.4 0.4 5 5 5 CSC-1 0.78 0.78 0.98 85 2 4 4 2 160 0.1 1.8 1.5 5 5 5 CSC-2 0.69 0.69 0.86 40 2 4 4 2 876 0.1 1.4 10.4 14 14 12 O-1 (EX. CONDITIONS OFFSITE) 0.20 0.20 0.25 40 33 3 3 3 0 0.0 1.0 0.0 5 5 5 O-2 (EX. CONDITIONS OFFSITE) 0.20 0.20 0.25 40 33 3 3 3 0 0.0 1.0 0.0 5 5 5 O-3 (EX. CONDITIONS OFFSITE) 0.20 0.20 0.25 40 33 3 3 3 0 3.6 3.6 0.0 5 5 5 O-4 (EX. CONDITIONS OFFSITE) 0.20 0.20 0.25 40 33 3 3 3 0 3.6 3.6 0.0 5 5 5 O-5 (EX. CONDITIONS OFFSITE) 0.20 0.20 0.25 40 33 3 3 3 0 3.6 3.6 0.0 5 5 5 O-6 (EX. CONDITIONS OFFSITE) 0.20 0.20 0.25 50 33 4 4 4 0 3.6 3.6 0.0 5 5 5 O-7 (EX. CONDITIONS OFFSITE) 0.20 0.20 0.25 50 33 4 4 4 0 3.6 3.6 0.0 5 5 5 O-8 (EX. CONDITIONS OFFSITE) 0.60 0.60 0.75 26 2 4 4 3 440 3.6 3.6 2.0 6 6 5 Basin Table A-2 Basin Time of Concentration Frequency Adj. Runoff Coefficients (C*Cf) C2 C10 C100 Overland Travel Time Time of Concentration Tc = Tov + Tt (min) Appendix A H23 Final Drainage Report 2 - year 10 - year 100 - year 2 - year 10 - year 100 - year 2 - Year 10 - Year 100 - Year 2 - Year 10 - Year 100 - Year N-1 3.27 0.80 0.80 1.00 9 9 5 2.30 3.93 9.95 6.0 10.3 32.5 N-2 2.93 0.34 0.34 0.42 12 12 11 2.05 3.50 7.42 2.0 3.4 9.1 N-3 1.50 0.86 0.86 1.00 8 8 6 2.40 4.10 9.31 3.1 5.3 14.0 N-4 0.52 0.59 0.59 0.74 9 9 7 2.30 3.93 8.80 0.7 1.2 3.4 N-5 1.54 0.54 0.54 0.68 10 10 8 2.21 3.78 8.38 1.8 3.1 8.7 S-1 4.95 0.74 0.74 0.92 11 11 9 2.13 3.63 8.03 7.8 13.3 36.7 S-2 1.16 0.65 0.65 0.81 7 7 6 2.52 4.31 9.31 1.9 3.2 8.7 S-3 1.07 0.80 0.80 1.00 6 6 5 2.67 4.56 9.95 2.3 3.9 10.6 S-4 2.79 0.24 0.24 0.30 14 14 13 1.92 3.29 6.92 1.3 2.2 5.7 S-5 1.20 0.62 0.62 0.77 8 8 6 2.40 4.10 9.31 1.8 3.0 8.6 S-6 0.35 0.44 0.44 0.54 7 7 6 2.52 4.31 9.31 0.4 0.7 1.8 U-1 2.09 0.77 0.77 0.96 8 8 6 2.40 4.10 9.31 3.9 6.6 18.7 U-2 3.48 0.63 0.63 0.78 12 12 10 2.05 3.50 7.72 4.5 7.6 21.0 U-3 0.12 0.64 0.64 0.80 5 5 5 2.85 4.87 9.95 0.2 0.4 1.0 CSC-1 0.98 0.78 0.78 0.98 5 5 5 2.85 4.87 9.95 2.2 3.7 9.5 CSC-2 3.06 0.69 0.69 0.86 14 14 12 1.92 3.29 7.16 4.1 6.9 18.9 O-1 (EX. CONDITIONS OFFSITE) 0.16 0.20 0.20 0.25 5 5 5 2.85 4.87 9.95 0.1 0.2 0.4 O-2 (EX. CONDITIONS OFFSITE) 0.09 0.20 0.20 0.25 5 5 5 2.85 4.87 9.95 0.1 0.1 0.2 O-3 (EX. CONDITIONS OFFSITE) 0.19 0.20 0.20 0.25 5 5 5 2.85 4.87 9.95 0.1 0.2 0.5 O-4 (EX. CONDITIONS OFFSITE) 0.43 0.20 0.20 0.25 5 5 5 2.85 4.87 9.95 0.2 0.4 1.1 O-5 (EX. CONDITIONS OFFSITE) 0.38 0.20 0.20 0.25 5 5 5 2.85 4.87 9.95 0.2 0.4 0.9 O-6 (EX. CONDITIONS OFFSITE) 0.31 0.20 0.20 0.25 5 5 5 2.85 4.87 9.95 0.2 0.3 0.8 O-7 (EX. CONDITIONS OFFSITE) 0.78 0.20 0.20 0.25 5 5 5 2.85 4.87 9.95 0.4 0.8 1.9 O-8 (EX. CONDITIONS OFFSITE) 0.52 0.60 0.60 0.75 6 6 5 2.67 4.56 9.95 0.8 1.4 3.9 Total Bypass Flow 9.7 Time of Concentration, Tc (min) Table A-3 Basin Peak Discharge Basin Rainfall Intensity (in/hr) Peak Discharge (cfs) Basin Area (ac) Frequency Adj. Runoff Coefficients Appendix A H23 Final Drainage Report 2 - year 10 - year 100 - year 2 - year 10 - year 100 - year 2 - year 10 - year 100 - year 2 - year 10 - year 100 - year 1 (Pond A Outlet) All "N" Basins, O-1, O-2, O-3 10.20 12 12 11 0.60 0.52 0.64 2.05 3.50 7.42 12.53 18.48 48.13 *2 (INLET-1D) Pond A Release, U-1, O- 1, O-2, O-3 2.53 8 8 6 0.67 0.67 0.84 2.40 4.10 9.31 5.69 8.57 21.38 *3 (SDMH-1D) Pond A Release, U-1, O- 1, O-2, O-3 CSC-1 3.51 8 8 6 0.70 0.70 0.88 2.40 4.10 9.31 7.53 11.72 30.29 *4 (SDMH-1C) Pond A Release, "U" Basins, O-1, O-2, O-3, CSC-1, CSC-2 10.17 14 14 12 0.67 0.67 0.84 1.92 3.29 7.16 14.73 24.10 62.78 *5 (SDMH-1A) Pond A and B Release, "U" and "O" Basins, CSC-1, CSC-2 12.59 14 14 12 0.60 0.60 0.75 1.92 3.29 7.16 18.24 27.61 66.29 6 (CURB CUT #1) N-4, O-1 0.68 9 9 7 0.50 0.50 0.62 2.30 3.93 8.80 0.78 1.33 3.72 7 (FES-4B) N-2, N-4, O-1 3.61 12 12 11 0.37 0.37 0.46 2.05 3.50 7.42 2.71 4.63 12.26 8 (INLET-3A) N-3, O-2 1.59 8 8 6 0.82 0.82 0.96 2.40 4.10 9.31 3.14 5.36 14.17 9 (INLET-2A) N-1, O-3 3.43 9 9 5 0.77 0.77 0.97 2.30 3.93 9.95 6.09 10.41 32.95 10 (INLET-5B) S-1, O-4 5.38 11 11 9 0.69 0.69 0.87 2.13 3.63 8.03 7.96 13.57 37.53 11 (INLET-5C) S-2, O-5 1.54 7 7 6 0.54 0.54 0.67 2.52 4.31 9.31 2.08 3.56 9.61 12 (SDMH-5A) S-1, S-2, O-4, O-5 6.92 11 11 9 0.66 0.66 0.82 2.13 3.63 8.03 9.72 16.57 45.81 13 (INLET-5A) S-1, S-2, S-3, S-6, O-4, O-5, O-6 8.65 11 11 9 0.65 0.65 0.81 2.13 3.63 8.03 12.01 20.46 56.56 14 (INLET-6A) S-5, O-8 1.72 8 8 6 0.61 0.61 0.77 2.40 4.10 9.31 2.54 4.33 12.30 **13 (INLET-5A ONLY) S-3, O-6 1.38 6 6 5 0.67 0.67 0.83 2.67 4.56 9.95 2.46 4.20 11.42 **4 (INLET-1A ONLY) U-2, U-3 3.60 12 12 10 0.63 0.63 0.78 2.05 3.50 7.72 4.63 7.90 21.78 14 (Pond B Outlet) All "S" Basins, O-4, O-5, O-6, O-7, O-8 13.94 14 14 13 0.54 0.54 0.67 1.92 3.29 6.92 14.42 24.72 64.96 Table A-4 Attenuation of Peak Discharge Time of Concentration, Tc (min) Weighted Runoff Coefficient Rainfall Intensity (in/hr) Peak Discharge (cfs) Area (acres) Contributing Basins & Design Point Design Points *Areas shown for these design points exclude the basin areas contributing to Ponds A and B. However, the release rates from these ponds have been added to the peak discharge column. All offsite basins have been attenuated thorugh the site and are considered bypass flows only. Runoff from these basins will be included in strom infrastructure sizing and are represented in the total peak discharge shown on this page. **Includes surface runoff to inlet only. Appendix A APPENDIX B Street Capacity and Inlet Analysis H23 Final Drainage Report Design Point Contributing Area (acres) 2-yr Design Flow (cfs) 100-yr Design Flow (cfs) 2-yr Allowable Ponding Depth (in) 100-yr Allowable Ponding Depth (in) Allowable 2-yr Capacity (cfs) Allowable 100-yr Capacity (cfs) Inlet Type Length (ft) Grade Condition Inlet-1A 3.60 4.63 21.78 4.4 9.2 4.9 36.0 CDOT Type R 20 Sump Inlet-1B 3.06 4.06 18.90 4.4 9.2 4.9 36.0 CDOT Type R 20 Sump Inlet-1C 0.98 2.18 9.53 4.4 9.2 3.4 20.3 CDOT Type R 10 Sump Inlet-1D 2.09 3.87 18.74 4.4 9.2 4.9 36.0 CDOT Type R 20 Sump Inlet-2A 3.4 6.09 32.95 6.0 **12 8.3 ****25.5 CDOT Type R 10 Sump Inlet-3A 1.6 3.14 14.17 6.0 **12 8.3 25.5 CDOT Type R 10 Sump Inlet-5A 1.4 2.46 11.42 6.0 18 8.3 25.5 CDOT Type R 10 Sump Inlet-5B 5.4 7.96 37.53 6.0 18 9.7 47.6 CDOT Type R 15 Sump Inlet-5C 1.5 2.08 9.61 6.0 **8 8.3 16.3 CDOT Type R 10 Sump *Inlet-5D 0.2 0.19 0.89 6.0 18 2.2 ***2.8 Nyoplast 18" Pedestrian Grate Area Inlet N/A Sump *Inlet-5E 0.2 0.19 0.89 6.0 18 2.2 ***2.8 Nyoplast 18" Pedestrian Grate Area Inlet N/A Sump Inlet-6A 1.72 2.54 12.30 4.4 9.2 3.4 20.3 CDOT Type R 10 Sump *Inlet-7A 1.09 1.30 6.18 6.0 18 6.6 ***9.4 Nyoplast 30" Pedestrian Grate Area Inlet N/A Sump *Inlet-7B 0.4 0.48 2.27 6.0 **12 2.2 2.8 Nyoplast 18" Pedestrian Grate Area Inlet N/A Sump *Inlet-7C 0.05 0.06 0.28 6.0 **12 2.2 2.8 Nyoplast 18" Pedestrian Grate Area Inlet N/A Sump Note: Allowable ponding depths at inlets within Strauss Cabin Road based on spread criteria. *Design flow shown for these basins is based on the contributing area times the cfs/acre for the subbasins draining to these inlets. **Allowable ponding depth at thses inlets is 18" for 100-yr event. However depths shown are maximum depths prior to overtopping and spilling into either another basin or pond. ***The depth shown is based on a head of 12", the Nyoplast charts do not extend up to 18" ponding depth. ****The 100-yr design storm at this inlet exceeds the inlet capacity. However, runoff not captured in this inlet will overtop the curb and sidewalk and spill directly into the pond. Table B-1 Inlet Summary Note: Area inlet capacity calculations based on graphs provided by Nyoplast manufacture. Refer to appendix. All area inlets to be Nyoplast Pedestrian Safe Grate or approved equal. Appendix B Project: Inlet ID: Gutter Geometry (Enter data in the blue cells) Maximum Allowable Width for Spread Behind Curb TBACK = 16.0 ft Side Slope Behind Curb (leave blank for no conveyance credit behind curb) SBACK = 0.020 ft/ft Manning's Roughness Behind Curb (typically between 0.012 and 0.020) nBACK = 0.020 Height of Curb at Gutter Flow Line HCURB = 6.00 inches Distance from Curb Face to Street Crown TCROWN = 40.0 ft Gutter Width W = 2.00 ft Street Transverse Slope SX = 0.020 ft/ft Gutter Cross Slope (typically 2 inches over 24 inches or 0.083 ft/ft) SW = 0.083 ft/ft Street Longitudinal Slope - Enter 0 for sump condition SO = 0.000 ft/ft Manning's Roughness for Street Section (typically between 0.012 and 0.020) nSTREET = 0.013 Minor Storm Major Storm Max. Allowable Spread for Minor & Major Storm TMAX = 12.0 32.0 ft Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX = 6.0 12.0 inches Allow Flow Depth at Street Crown (leave blank for no) check = yes MINOR STORM Allowable Capacity is based on Depth Criterion Minor Storm Major Storm MAJOR STORM Allowable Capacity is based on Depth Criterion Qallow = SUMP SUMP cfs ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm) (Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread) H23 Inlet-1A UD-Inlet_v4.01, Inlet-1A 2/24/2017, 9:08 AM Design Information (Input) MINOR MAJOR Type of Inlet Type = Local Depression (additional to continuous gutter depression 'a' from 'Q-Allow') alocal = 3.00 3.00 inches Number of Unit Inlets (Grate or Curb Opening) No = 1 1 Water Depth at Flowline (outside of local depression) Ponding Depth = 4.4 9.2 inches Grate Information MINOR MAJOR Length of a Unit Grate Lo (G) = N/A N/A feet Width of a Unit Grate Wo = N/A N/A feet Area Opening Ratio for a Grate (typical values 0.15-0.90) Aratio = N/A N/A Clogging Factor for a Single Grate (typical value 0.50 - 0.70) Cf (G) = N/A N/A Grate Weir Coefficient (typical value 2.15 - 3.60) Cw (G) = N/A N/A Grate Orifice Coefficient (typical value 0.60 - 0.80) Co (G) = N/A N/A Curb Opening Information MINOR MAJOR Length of a Unit Curb Opening Lo (C) = 20.00 20.00 feet Height of Vertical Curb Opening in Inches Hvert = 6.00 6.00 inches Height of Curb Orifice Throat in Inches Hthroat = 6.00 6.00 inches Angle of Throat (see USDCM Figure ST-5) Theta = 63.40 63.40 degrees Side Width for Depression Pan (typically the gutter width of 2 feet) Wp = 2.00 2.00 feet Clogging Factor for a Single Curb Opening (typical value 0.10) Cf (C) = 0.10 0.10 Curb Opening Weir Coefficient (typical value 2.3-3.7) Cw (C) = 3.60 3.60 Curb Opening Orifice Coefficient (typical value 0.60 - 0.70) Co (C) = 0.67 0.67 Low Head Performance Reduction (Calculated) MINOR MAJOR Depth for Grate Midwidth dGrate = N/A N/A ft Depth for Curb Opening Weir Equation dCurb = 0.20 0.60 ft Combination Inlet Performance Reduction Factor for Long Inlets RFCombination = 0.42 0.87 Curb Opening Performance Reduction Factor for Long Inlets RFCurb = 0.67 0.94 Grated Inlet Performance Reduction Factor for Long Inlets RFGrate = N/A N/A MINOR MAJOR Total Inlet Interception Capacity (assumes clogged condition) Qa = 4.9 36.0 cfs Inlet Capacity IS GOOD for Minor and Major Storms(>Q PEAK) Q PEAK REQUIRED = 4.6 21.8 cfs INLET IN A SUMP OR SAG LOCATION CDOT Type R Curb Opening H-Vert H-Curb W Lo (C) Lo (G) Wo WP CDOT Type R Curb Opening Override Depths UD-Inlet_v4.01, Inlet-1A 2/24/2017, 9:08 AM Project: Inlet ID: Gutter Geometry (Enter data in the blue cells) Maximum Allowable Width for Spread Behind Curb TBACK = 16.0 ft Side Slope Behind Curb (leave blank for no conveyance credit behind curb) SBACK = 0.020 ft/ft Manning's Roughness Behind Curb (typically between 0.012 and 0.020) nBACK = 0.020 Height of Curb at Gutter Flow Line HCURB = 6.00 inches Distance from Curb Face to Street Crown TCROWN = 40.0 ft Gutter Width W = 2.00 ft Street Transverse Slope SX = 0.020 ft/ft Gutter Cross Slope (typically 2 inches over 24 inches or 0.083 ft/ft) SW = 0.083 ft/ft Street Longitudinal Slope - Enter 0 for sump condition SO = 0.000 ft/ft Manning's Roughness for Street Section (typically between 0.012 and 0.020) nSTREET = 0.013 Minor Storm Major Storm Max. Allowable Spread for Minor & Major Storm TMAX = 12.0 32.0 ft Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX = 6.0 12.0 inches Allow Flow Depth at Street Crown (leave blank for no) check = yes MINOR STORM Allowable Capacity is based on Depth Criterion Minor Storm Major Storm MAJOR STORM Allowable Capacity is based on Depth Criterion Qallow = SUMP SUMP cfs ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm) (Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread) H23 Inlet-1B UD-Inlet_v4.01, Inlet-1B 2/24/2017, 9:08 AM Design Information (Input) MINOR MAJOR Type of Inlet Type = Local Depression (additional to continuous gutter depression 'a' from 'Q-Allow') alocal = 3.00 3.00 inches Number of Unit Inlets (Grate or Curb Opening) No = 1 1 Water Depth at Flowline (outside of local depression) Ponding Depth = 4.4 9.2 inches Grate Information MINOR MAJOR Length of a Unit Grate Lo (G) = N/A N/A feet Width of a Unit Grate Wo = N/A N/A feet Area Opening Ratio for a Grate (typical values 0.15-0.90) Aratio = N/A N/A Clogging Factor for a Single Grate (typical value 0.50 - 0.70) Cf (G) = N/A N/A Grate Weir Coefficient (typical value 2.15 - 3.60) Cw (G) = N/A N/A Grate Orifice Coefficient (typical value 0.60 - 0.80) Co (G) = N/A N/A Curb Opening Information MINOR MAJOR Length of a Unit Curb Opening Lo (C) = 20.00 20.00 feet Height of Vertical Curb Opening in Inches Hvert = 6.00 6.00 inches Height of Curb Orifice Throat in Inches Hthroat = 6.00 6.00 inches Angle of Throat (see USDCM Figure ST-5) Theta = 63.40 63.40 degrees Side Width for Depression Pan (typically the gutter width of 2 feet) Wp = 2.00 2.00 feet Clogging Factor for a Single Curb Opening (typical value 0.10) Cf (C) = 0.10 0.10 Curb Opening Weir Coefficient (typical value 2.3-3.7) Cw (C) = 3.60 3.60 Curb Opening Orifice Coefficient (typical value 0.60 - 0.70) Co (C) = 0.67 0.67 Low Head Performance Reduction (Calculated) MINOR MAJOR Depth for Grate Midwidth dGrate = N/A N/A ft Depth for Curb Opening Weir Equation dCurb = 0.20 0.60 ft Combination Inlet Performance Reduction Factor for Long Inlets RFCombination = 0.41 0.87 Curb Opening Performance Reduction Factor for Long Inlets RFCurb = 0.67 0.94 Grated Inlet Performance Reduction Factor for Long Inlets RFGrate = N/A N/A MINOR MAJOR Total Inlet Interception Capacity (assumes clogged condition) Qa = 4.9 36.0 cfs Inlet Capacity IS GOOD for Minor and Major Storms(>Q PEAK) Q PEAK REQUIRED = 4.1 18.9 cfs INLET IN A SUMP OR SAG LOCATION CDOT Type R Curb Opening H-Vert H-Curb W Lo (C) Lo (G) Wo WP CDOT Type R Curb Opening Override Depths UD-Inlet_v4.01, Inlet-1B 2/24/2017, 9:08 AM Project: Inlet ID: Gutter Geometry (Enter data in the blue cells) Maximum Allowable Width for Spread Behind Curb TBACK = 16.0 ft Side Slope Behind Curb (leave blank for no conveyance credit behind curb) SBACK = 0.020 ft/ft Manning's Roughness Behind Curb (typically between 0.012 and 0.020) nBACK = 0.020 Height of Curb at Gutter Flow Line HCURB = 6.00 inches Distance from Curb Face to Street Crown TCROWN = 40.0 ft Gutter Width W = 2.00 ft Street Transverse Slope SX = 0.020 ft/ft Gutter Cross Slope (typically 2 inches over 24 inches or 0.083 ft/ft) SW = 0.083 ft/ft Street Longitudinal Slope - Enter 0 for sump condition SO = 0.000 ft/ft Manning's Roughness for Street Section (typically between 0.012 and 0.020) nSTREET = 0.013 Minor Storm Major Storm Max. Allowable Spread for Minor & Major Storm TMAX = 12.0 32.0 ft Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX = 6.0 12.0 inches Allow Flow Depth at Street Crown (leave blank for no) check = yes MINOR STORM Allowable Capacity is based on Depth Criterion Minor Storm Major Storm MAJOR STORM Allowable Capacity is based on Depth Criterion Qallow = SUMP SUMP cfs ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm) (Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread) H23 Inlet-1C UD-Inlet_v4.01, Inlet-1C 2/24/2017, 9:09 AM Design Information (Input) MINOR MAJOR Type of Inlet Type = Local Depression (additional to continuous gutter depression 'a' from 'Q-Allow') alocal = 3.00 3.00 inches Number of Unit Inlets (Grate or Curb Opening) No = 1 1 Water Depth at Flowline (outside of local depression) Ponding Depth = 4.4 9.2 inches Grate Information MINOR MAJOR Length of a Unit Grate Lo (G) = N/A N/A feet Width of a Unit Grate Wo = N/A N/A feet Area Opening Ratio for a Grate (typical values 0.15-0.90) Aratio = N/A N/A Clogging Factor for a Single Grate (typical value 0.50 - 0.70) Cf (G) = N/A N/A Grate Weir Coefficient (typical value 2.15 - 3.60) Cw (G) = N/A N/A Grate Orifice Coefficient (typical value 0.60 - 0.80) Co (G) = N/A N/A Curb Opening Information MINOR MAJOR Length of a Unit Curb Opening Lo (C) = 10.00 10.00 feet Height of Vertical Curb Opening in Inches Hvert = 6.00 6.00 inches Height of Curb Orifice Throat in Inches Hthroat = 6.00 6.00 inches Angle of Throat (see USDCM Figure ST-5) Theta = 63.40 63.40 degrees Side Width for Depression Pan (typically the gutter width of 2 feet) Wp = 2.00 2.00 feet Clogging Factor for a Single Curb Opening (typical value 0.10) Cf (C) = 0.10 0.10 Curb Opening Weir Coefficient (typical value 2.3-3.7) Cw (C) = 3.60 3.60 Curb Opening Orifice Coefficient (typical value 0.60 - 0.70) Co (C) = 0.67 0.67 Low Head Performance Reduction (Calculated) MINOR MAJOR Depth for Grate Midwidth dGrate = N/A N/A ft Depth for Curb Opening Weir Equation dCurb = 0.20 0.60 ft Combination Inlet Performance Reduction Factor for Long Inlets RFCombination = 0.41 0.87 Curb Opening Performance Reduction Factor for Long Inlets RFCurb = 0.82 1.00 Grated Inlet Performance Reduction Factor for Long Inlets RFGrate = N/A N/A MINOR MAJOR Total Inlet Interception Capacity (assumes clogged condition) Qa = 3.4 20.3 cfs Inlet Capacity IS GOOD for Minor and Major Storms(>Q PEAK) Q PEAK REQUIRED = 2.2 9.5 cfs INLET IN A SUMP OR SAG LOCATION CDOT Type R Curb Opening H-Vert H-Curb W Lo (C) Lo (G) Wo WP CDOT Type R Curb Opening Override Depths UD-Inlet_v4.01, Inlet-1C 2/24/2017, 9:09 AM Project: Inlet ID: Gutter Geometry (Enter data in the blue cells) Maximum Allowable Width for Spread Behind Curb TBACK = 16.0 ft Side Slope Behind Curb (leave blank for no conveyance credit behind curb) SBACK = 0.020 ft/ft Manning's Roughness Behind Curb (typically between 0.012 and 0.020) nBACK = 0.020 Height of Curb at Gutter Flow Line HCURB = 6.00 inches Distance from Curb Face to Street Crown TCROWN = 40.0 ft Gutter Width W = 2.00 ft Street Transverse Slope SX = 0.020 ft/ft Gutter Cross Slope (typically 2 inches over 24 inches or 0.083 ft/ft) SW = 0.083 ft/ft Street Longitudinal Slope - Enter 0 for sump condition SO = 0.000 ft/ft Manning's Roughness for Street Section (typically between 0.012 and 0.020) nSTREET = 0.013 Minor Storm Major Storm Max. Allowable Spread for Minor & Major Storm TMAX = 12.0 32.0 ft Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX = 6.0 12.0 inches Allow Flow Depth at Street Crown (leave blank for no) check = yes MINOR STORM Allowable Capacity is based on Depth Criterion Minor Storm Major Storm MAJOR STORM Allowable Capacity is based on Depth Criterion Qallow = SUMP SUMP cfs ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm) (Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread) H23 Inlet-1D UD-Inlet_v4.01, Inlet-1D 2/24/2017, 9:09 AM Design Information (Input) MINOR MAJOR Type of Inlet Type = Local Depression (additional to continuous gutter depression 'a' from 'Q-Allow') alocal = 3.00 3.00 inches Number of Unit Inlets (Grate or Curb Opening) No = 1 1 Water Depth at Flowline (outside of local depression) Ponding Depth = 4.4 9.2 inches Grate Information MINOR MAJOR Length of a Unit Grate Lo (G) = N/A N/A feet Width of a Unit Grate Wo = N/A N/A feet Area Opening Ratio for a Grate (typical values 0.15-0.90) Aratio = N/A N/A Clogging Factor for a Single Grate (typical value 0.50 - 0.70) Cf (G) = N/A N/A Grate Weir Coefficient (typical value 2.15 - 3.60) Cw (G) = N/A N/A Grate Orifice Coefficient (typical value 0.60 - 0.80) Co (G) = N/A N/A Curb Opening Information MINOR MAJOR Length of a Unit Curb Opening Lo (C) = 20.00 20.00 feet Height of Vertical Curb Opening in Inches Hvert = 6.00 6.00 inches Height of Curb Orifice Throat in Inches Hthroat = 6.00 6.00 inches Angle of Throat (see USDCM Figure ST-5) Theta = 63.40 63.40 degrees Side Width for Depression Pan (typically the gutter width of 2 feet) Wp = 2.00 2.00 feet Clogging Factor for a Single Curb Opening (typical value 0.10) Cf (C) = 0.10 0.10 Curb Opening Weir Coefficient (typical value 2.3-3.7) Cw (C) = 3.60 3.60 Curb Opening Orifice Coefficient (typical value 0.60 - 0.70) Co (C) = 0.67 0.67 Low Head Performance Reduction (Calculated) MINOR MAJOR Depth for Grate Midwidth dGrate = N/A N/A ft Depth for Curb Opening Weir Equation dCurb = 0.20 0.60 ft Combination Inlet Performance Reduction Factor for Long Inlets RFCombination = 0.41 0.87 Curb Opening Performance Reduction Factor for Long Inlets RFCurb = 0.67 0.94 Grated Inlet Performance Reduction Factor for Long Inlets RFGrate = N/A N/A MINOR MAJOR Total Inlet Interception Capacity (assumes clogged condition) Qa = 4.9 36.0 cfs Inlet Capacity IS GOOD for Minor and Major Storms(>Q PEAK) Q PEAK REQUIRED = 3.9 18.7 cfs INLET IN A SUMP OR SAG LOCATION CDOT Type R Curb Opening H-Vert H-Curb W Lo (C) Lo (G) Wo WP CDOT Type R Curb Opening Override Depths UD-Inlet_v4.01, Inlet-1D 2/24/2017, 9:09 AM Design Information (Input) MINOR MAJOR Type of Inlet Type = Local Depression (additional to continuous gutter depression 'a' from 'Q-Allow') alocal = 3.00 3.00 inches Number of Unit Inlets (Grate or Curb Opening) No = 1 1 Water Depth at Flowline (outside of local depression) Ponding Depth = 6.0 12.0 inches Grate Information MINOR MAJOR Length of a Unit Grate Lo (G) = N/A N/A feet Width of a Unit Grate Wo = N/A N/A feet Area Opening Ratio for a Grate (typical values 0.15-0.90) Aratio = N/A N/A Clogging Factor for a Single Grate (typical value 0.50 - 0.70) Cf (G) = N/A N/A Grate Weir Coefficient (typical value 2.15 - 3.60) Cw (G) = N/A N/A Grate Orifice Coefficient (typical value 0.60 - 0.80) Co (G) = N/A N/A Curb Opening Information MINOR MAJOR Length of a Unit Curb Opening Lo (C) = 10.00 10.00 feet Height of Vertical Curb Opening in Inches Hvert = 6.00 6.00 inches Height of Curb Orifice Throat in Inches Hthroat = 6.00 6.00 inches Angle of Throat (see USDCM Figure ST-5) Theta = 63.40 63.40 degrees Side Width for Depression Pan (typically the gutter width of 2 feet) Wp = 2.00 2.00 feet Clogging Factor for a Single Curb Opening (typical value 0.10) Cf (C) = 0.10 0.10 Curb Opening Weir Coefficient (typical value 2.3-3.7) Cw (C) = 3.60 3.60 Curb Opening Orifice Coefficient (typical value 0.60 - 0.70) Co (C) = 0.67 0.67 Low Head Performance Reduction (Calculated) MINOR MAJOR Depth for Grate Midwidth dGrate = N/A N/A ft Depth for Curb Opening Weir Equation dCurb = 0.33 0.83 ft Combination Inlet Performance Reduction Factor for Long Inlets RFCombination = 0.57 1.00 Curb Opening Performance Reduction Factor for Long Inlets RFCurb = 0.93 1.00 Grated Inlet Performance Reduction Factor for Long Inlets RFGrate = N/A N/A MINOR MAJOR Total Inlet Interception Capacity (assumes clogged condition) Qa = 8.3 25.5 cfs WARNING: Inlet Capacity less than Q Peak for Major Storm Q PEAK REQUIRED = 6.1 33.0 cfs INLET IN A SUMP OR SAG LOCATION CDOT Type R Curb Opening H-Vert H-Curb W Lo (C) Lo (G) Wo WP CDOT Type R Curb Opening Override Depths UD-Inlet_v4.01, Inlet-2A 2/24/2017, 9:10 AM Design Information (Input) MINOR MAJOR Type of Inlet Type = Local Depression (additional to continuous gutter depression 'a' from 'Q-Allow') alocal = 3.00 3.00 inches Number of Unit Inlets (Grate or Curb Opening) No = 1 1 Water Depth at Flowline (outside of local depression) Ponding Depth = 6.0 12.0 inches Grate Information MINOR MAJOR Length of a Unit Grate Lo (G) = N/A N/A feet Width of a Unit Grate Wo = N/A N/A feet Area Opening Ratio for a Grate (typical values 0.15-0.90) Aratio = N/A N/A Clogging Factor for a Single Grate (typical value 0.50 - 0.70) Cf (G) = N/A N/A Grate Weir Coefficient (typical value 2.15 - 3.60) Cw (G) = N/A N/A Grate Orifice Coefficient (typical value 0.60 - 0.80) Co (G) = N/A N/A Curb Opening Information MINOR MAJOR Length of a Unit Curb Opening Lo (C) = 10.00 10.00 feet Height of Vertical Curb Opening in Inches Hvert = 6.00 6.00 inches Height of Curb Orifice Throat in Inches Hthroat = 6.00 6.00 inches Angle of Throat (see USDCM Figure ST-5) Theta = 63.40 63.40 degrees Side Width for Depression Pan (typically the gutter width of 2 feet) Wp = 2.00 2.00 feet Clogging Factor for a Single Curb Opening (typical value 0.10) Cf (C) = 0.10 0.10 Curb Opening Weir Coefficient (typical value 2.3-3.7) Cw (C) = 3.60 3.60 Curb Opening Orifice Coefficient (typical value 0.60 - 0.70) Co (C) = 0.67 0.67 Low Head Performance Reduction (Calculated) MINOR MAJOR Depth for Grate Midwidth dGrate = N/A N/A ft Depth for Curb Opening Weir Equation dCurb = 0.33 0.83 ft Combination Inlet Performance Reduction Factor for Long Inlets RFCombination = 0.57 1.00 Curb Opening Performance Reduction Factor for Long Inlets RFCurb = 0.93 1.00 Grated Inlet Performance Reduction Factor for Long Inlets RFGrate = N/A N/A MINOR MAJOR Total Inlet Interception Capacity (assumes clogged condition) Qa = 8.3 25.5 cfs Inlet Capacity IS GOOD for Minor and Major Storms(>Q PEAK) Q PEAK REQUIRED = 3.1 14.2 cfs INLET IN A SUMP OR SAG LOCATION CDOT Type R Curb Opening H-Vert H-Curb W Lo (C) Lo (G) Wo WP CDOT Type R Curb Opening Override Depths UD-Inlet_v4.01, Inlet-3A 2/24/2017, 9:10 AM Design Information (Input) MINOR MAJOR Type of Inlet Type = Local Depression (additional to continuous gutter depression 'a' from 'Q-Allow') alocal = 3.00 3.00 inches Number of Unit Inlets (Grate or Curb Opening) No = 1 1 Water Depth at Flowline (outside of local depression) Ponding Depth = 6.0 12.0 inches Grate Information MINOR MAJOR Length of a Unit Grate Lo (G) = N/A N/A feet Width of a Unit Grate Wo = N/A N/A feet Area Opening Ratio for a Grate (typical values 0.15-0.90) Aratio = N/A N/A Clogging Factor for a Single Grate (typical value 0.50 - 0.70) Cf (G) = N/A N/A Grate Weir Coefficient (typical value 2.15 - 3.60) Cw (G) = N/A N/A Grate Orifice Coefficient (typical value 0.60 - 0.80) Co (G) = N/A N/A Curb Opening Information MINOR MAJOR Length of a Unit Curb Opening Lo (C) = 10.00 10.00 feet Height of Vertical Curb Opening in Inches Hvert = 6.00 6.00 inches Height of Curb Orifice Throat in Inches Hthroat = 6.00 6.00 inches Angle of Throat (see USDCM Figure ST-5) Theta = 63.40 63.40 degrees Side Width for Depression Pan (typically the gutter width of 2 feet) Wp = 2.00 2.00 feet Clogging Factor for a Single Curb Opening (typical value 0.10) Cf (C) = 0.10 0.10 Curb Opening Weir Coefficient (typical value 2.3-3.7) Cw (C) = 3.60 3.60 Curb Opening Orifice Coefficient (typical value 0.60 - 0.70) Co (C) = 0.67 0.67 Low Head Performance Reduction (Calculated) MINOR MAJOR Depth for Grate Midwidth dGrate = N/A N/A ft Depth for Curb Opening Weir Equation dCurb = 0.33 0.83 ft Combination Inlet Performance Reduction Factor for Long Inlets RFCombination = 0.57 1.00 Curb Opening Performance Reduction Factor for Long Inlets RFCurb = 0.93 1.00 Grated Inlet Performance Reduction Factor for Long Inlets RFGrate = N/A N/A MINOR MAJOR Total Inlet Interception Capacity (assumes clogged condition) Qa = 8.3 25.5 cfs Inlet Capacity IS GOOD for Minor and Major Storms(>Q PEAK) Q PEAK REQUIRED = 2.5 11.4 cfs INLET IN A SUMP OR SAG LOCATION CDOT Type R Curb Opening H-Vert H-Curb W Lo (C) Lo (G) Wo WP CDOT Type R Curb Opening Override Depths UD-Inlet_v4.01, Inlet-5A 2/24/2017, 9:18 AM Design Information (Input) MINOR MAJOR Type of Inlet Type = Local Depression (additional to continuous gutter depression 'a' from 'Q-Allow') alocal = 3.00 3.00 inches Number of Unit Inlets (Grate or Curb Opening) No = 1 1 Water Depth at Flowline (outside of local depression) Ponding Depth = 6.0 18.0 inches Grate Information MINOR MAJOR Length of a Unit Grate Lo (G) = N/A N/A feet Width of a Unit Grate Wo = N/A N/A feet Area Opening Ratio for a Grate (typical values 0.15-0.90) Aratio = N/A N/A Clogging Factor for a Single Grate (typical value 0.50 - 0.70) Cf (G) = N/A N/A Grate Weir Coefficient (typical value 2.15 - 3.60) Cw (G) = N/A N/A Grate Orifice Coefficient (typical value 0.60 - 0.80) Co (G) = N/A N/A Curb Opening Information MINOR MAJOR Length of a Unit Curb Opening Lo (C) = 15.00 15.00 feet Height of Vertical Curb Opening in Inches Hvert = 6.00 6.00 inches Height of Curb Orifice Throat in Inches Hthroat = 6.00 6.00 inches Angle of Throat (see USDCM Figure ST-5) Theta = 63.40 63.40 degrees Side Width for Depression Pan (typically the gutter width of 2 feet) Wp = 2.00 2.00 feet Clogging Factor for a Single Curb Opening (typical value 0.10) Cf (C) = 0.10 0.10 Curb Opening Weir Coefficient (typical value 2.3-3.7) Cw (C) = 3.60 3.60 Curb Opening Orifice Coefficient (typical value 0.60 - 0.70) Co (C) = 0.67 0.67 Low Head Performance Reduction (Calculated) MINOR MAJOR Depth for Grate Midwidth dGrate = N/A N/A ft Depth for Curb Opening Weir Equation dCurb = 0.33 1.33 ft Combination Inlet Performance Reduction Factor for Long Inlets RFCombination = 0.57 1.00 Curb Opening Performance Reduction Factor for Long Inlets RFCurb = 0.79 1.00 Grated Inlet Performance Reduction Factor for Long Inlets RFGrate = N/A N/A MINOR MAJOR Total Inlet Interception Capacity (assumes clogged condition) Qa = 9.7 47.6 cfs Inlet Capacity IS GOOD for Minor and Major Storms(>Q PEAK) Q PEAK REQUIRED = 8.0 37.5 cfs INLET IN A SUMP OR SAG LOCATION CDOT Type R Curb Opening H-Vert H-Curb W Lo (C) Lo (G) Wo WP CDOT Type R Curb Opening Override Depths UD-Inlet_v4.01, Inlet-5B 2/24/2017, 9:11 AM Design Information (Input) MINOR MAJOR Type of Inlet Type = Local Depression (additional to continuous gutter depression 'a' from 'Q-Allow') alocal = 3.00 3.00 inches Number of Unit Inlets (Grate or Curb Opening) No = 1 1 Water Depth at Flowline (outside of local depression) Ponding Depth = 6.0 8.0 inches Grate Information MINOR MAJOR Length of a Unit Grate Lo (G) = N/A N/A feet Width of a Unit Grate Wo = N/A N/A feet Area Opening Ratio for a Grate (typical values 0.15-0.90) Aratio = N/A N/A Clogging Factor for a Single Grate (typical value 0.50 - 0.70) Cf (G) = N/A N/A Grate Weir Coefficient (typical value 2.15 - 3.60) Cw (G) = N/A N/A Grate Orifice Coefficient (typical value 0.60 - 0.80) Co (G) = N/A N/A Curb Opening Information MINOR MAJOR Length of a Unit Curb Opening Lo (C) = 10.00 10.00 feet Height of Vertical Curb Opening in Inches Hvert = 6.00 6.00 inches Height of Curb Orifice Throat in Inches Hthroat = 6.00 6.00 inches Angle of Throat (see USDCM Figure ST-5) Theta = 63.40 63.40 degrees Side Width for Depression Pan (typically the gutter width of 2 feet) Wp = 2.00 2.00 feet Clogging Factor for a Single Curb Opening (typical value 0.10) Cf (C) = 0.10 0.10 Curb Opening Weir Coefficient (typical value 2.3-3.7) Cw (C) = 3.60 3.60 Curb Opening Orifice Coefficient (typical value 0.60 - 0.70) Co (C) = 0.67 0.67 Low Head Performance Reduction (Calculated) MINOR MAJOR Depth for Grate Midwidth dGrate = N/A N/A ft Depth for Curb Opening Weir Equation dCurb = 0.33 0.50 ft Combination Inlet Performance Reduction Factor for Long Inlets RFCombination = 0.57 0.75 Curb Opening Performance Reduction Factor for Long Inlets RFCurb = 0.93 1.00 Grated Inlet Performance Reduction Factor for Long Inlets RFGrate = N/A N/A MINOR MAJOR Total Inlet Interception Capacity (assumes clogged condition) Qa = 8.3 16.3 cfs Inlet Capacity IS GOOD for Minor and Major Storms(>Q PEAK) Q PEAK REQUIRED = 2.1 9.6 cfs INLET IN A SUMP OR SAG LOCATION CDOT Type R Curb Opening H-Vert H-Curb W Lo (C) Lo (G) Wo WP CDOT Type R Curb Opening Override Depths UD-Inlet_v4.01, Inlet-5C 2/24/2017, 9:12 AM 3130 Verona Avenue • Buford, GA 30518 (866) 888-8479 / (770) 932-2443 • Fax: (770) 932-2490 © Nyloplast Inlet Capacity Charts June 2012 0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45 0.50 0.55 0.60 0.65 0.70 0.75 0.80 0.85 0.90 0.95 1.00 1.05 1.10 Capacity (cfs) Head (ft) Nyloplast 18" Pedestrian Grate Inlet Capacity Chart 3130 Verona Avenue • Buford, GA 30518 (866) 888-8479 / (770) 932-2443 • Fax: (770) 932-2490 © Nyloplast Inlet Capacity Charts June 2012 0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45 0.50 0.55 0.60 0.65 0.70 0.75 0.80 0.85 0.90 0.95 1.00 1.05 1.10 Capacity (cfs) Head (ft) Nyloplast 18" Pedestrian Grate Inlet Capacity Chart Project: Inlet ID: Gutter Geometry (Enter data in the blue cells) Maximum Allowable Width for Spread Behind Curb TBACK = 16.0 ft Side Slope Behind Curb (leave blank for no conveyance credit behind curb) SBACK = 0.020 ft/ft Manning's Roughness Behind Curb (typically between 0.012 and 0.020) nBACK = 0.020 Height of Curb at Gutter Flow Line HCURB = 6.00 inches Distance from Curb Face to Street Crown TCROWN = 40.0 ft Gutter Width W = 2.00 ft Street Transverse Slope SX = 0.020 ft/ft Gutter Cross Slope (typically 2 inches over 24 inches or 0.083 ft/ft) SW = 0.083 ft/ft Street Longitudinal Slope - Enter 0 for sump condition SO = 0.000 ft/ft Manning's Roughness for Street Section (typically between 0.012 and 0.020) nSTREET = 0.013 Minor Storm Major Storm Max. Allowable Spread for Minor & Major Storm TMAX = 12.0 32.0 ft Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX = 6.0 12.0 inches Allow Flow Depth at Street Crown (leave blank for no) check = yes MINOR STORM Allowable Capacity is based on Depth Criterion Minor Storm Major Storm MAJOR STORM Allowable Capacity is based on Depth Criterion Qallow = SUMP SUMP cfs ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm) (Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread) H23 Inlet-6A UD-Inlet_v4.01, Inlet-6A 2/24/2017, 9:12 AM Design Information (Input) MINOR MAJOR Type of Inlet Type = Local Depression (additional to continuous gutter depression 'a' from 'Q-Allow') alocal = 3.00 3.00 inches Number of Unit Inlets (Grate or Curb Opening) No = 1 1 Water Depth at Flowline (outside of local depression) Ponding Depth = 4.4 9.2 inches Grate Information MINOR MAJOR Length of a Unit Grate Lo (G) = N/A N/A feet Width of a Unit Grate Wo = N/A N/A feet Area Opening Ratio for a Grate (typical values 0.15-0.90) Aratio = N/A N/A Clogging Factor for a Single Grate (typical value 0.50 - 0.70) Cf (G) = N/A N/A Grate Weir Coefficient (typical value 2.15 - 3.60) Cw (G) = N/A N/A Grate Orifice Coefficient (typical value 0.60 - 0.80) Co (G) = N/A N/A Curb Opening Information MINOR MAJOR Length of a Unit Curb Opening Lo (C) = 10.00 10.00 feet Height of Vertical Curb Opening in Inches Hvert = 6.00 6.00 inches Height of Curb Orifice Throat in Inches Hthroat = 6.00 6.00 inches Angle of Throat (see USDCM Figure ST-5) Theta = 63.40 63.40 degrees Side Width for Depression Pan (typically the gutter width of 2 feet) Wp = 2.00 2.00 feet Clogging Factor for a Single Curb Opening (typical value 0.10) Cf (C) = 0.10 0.10 Curb Opening Weir Coefficient (typical value 2.3-3.7) Cw (C) = 3.60 3.60 Curb Opening Orifice Coefficient (typical value 0.60 - 0.70) Co (C) = 0.67 0.67 Low Head Performance Reduction (Calculated) MINOR MAJOR Depth for Grate Midwidth dGrate = N/A N/A ft Depth for Curb Opening Weir Equation dCurb = 0.20 0.60 ft Combination Inlet Performance Reduction Factor for Long Inlets RFCombination = 0.41 0.87 Curb Opening Performance Reduction Factor for Long Inlets RFCurb = 0.82 1.00 Grated Inlet Performance Reduction Factor for Long Inlets RFGrate = N/A N/A MINOR MAJOR Total Inlet Interception Capacity (assumes clogged condition) Qa = 3.4 20.3 cfs Inlet Capacity IS GOOD for Minor and Major Storms(>Q PEAK) Q PEAK REQUIRED = 2.5 12.3 cfs INLET IN A SUMP OR SAG LOCATION CDOT Type R Curb Opening H-Vert H-Curb W Lo (C) Lo (G) Wo WP CDOT Type R Curb Opening Override Depths UD-Inlet_v4.01, Inlet-6A 2/24/2017, 9:12 AM 3130 Verona Avenue • Buford, GA 30518 (866) 888-8479 / (770) 932-2443 • Fax: (770) 932-2490 © Nyloplast Inlet Capacity Charts June 2012 0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 11.00 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45 0.50 0.55 0.60 0.65 0.70 0.75 0.80 0.85 0.90 0.95 1.00 1.05 1.10 Capacity (cfs) Head (ft) Nyloplast 30" Pedestrian Grate Inlet Capacity Chart 3130 Verona Avenue • Buford, GA 30518 (866) 888-8479 / (770) 932-2443 • Fax: (770) 932-2490 © Nyloplast Inlet Capacity Charts June 2012 0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45 0.50 0.55 0.60 0.65 0.70 0.75 0.80 0.85 0.90 0.95 1.00 1.05 1.10 Capacity (cfs) Head (ft) Nyloplast 18" Pedestrian Grate Inlet Capacity Chart 3130 Verona Avenue • Buford, GA 30518 (866) 888-8479 / (770) 932-2443 • Fax: (770) 932-2490 © Nyloplast Inlet Capacity Charts June 2012 0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45 0.50 0.55 0.60 0.65 0.70 0.75 0.80 0.85 0.90 0.95 1.00 1.05 1.10 Capacity (cfs) Head (ft) Nyloplast 18" Pedestrian Grate Inlet Capacity Chart APPENDIX C Storm Sewer Design H23 Final Drainage Report Storm ID From (Downstream) To (Upstream) UD Sewer Pipe ID Design Flow (cfs) Pipe Diameter (in) Pipe Material FES-1A MH-1A 1A 66.29 60 RCP MH-1A MH-1B 1B 62.78 54 RCP MH-1B MH-1C 1C 62.78 54 RCP MH-1C MH-1D 1D 30.29 48 RCP MH-1D INLET-1D 1E 21.38 36 RCP INLET-1D POND A OUTLET 1F 2.70 18 RCP ST-01A MH-1D INLET-1C 1G 9.53 18 RCP ST-01B MH-1C INLET-1A 1H 21.78 24 RCP ST-01B MH-1C INLET-1B 1I 18.90 24 RCP *ST-01C MH-1A POND B OUTLET 1J 10.53 36 RCP ST-02 FES-2A INLET-2A 2A 32.95 36 RCP ST-03 FES-3A INLET-3A 3A 14.17 24 RCP FES-5A INLET-5A 5A 56.56 48 RCP INLET-5A MH-5A 5B 45.81 48 RCP MH-5A MH-5B 5C 45.81 48 RCP MH-5B INLET-5B 5D 37.53 36 RCP ST-05A MH-5A INLET-5C 5E 9.61 36 RCP INLET-5A INLET-5D 5F 1.77 18 ADS INLET-5D INLET-5E 5G 0.89 18 ADS ST-06 FES-6A INLET-6A 6A 12.30 24 RCP ST-07 FES-7A INLET-7A 7A 8.73 24 ADS ST-08 INLET-7A INLET-7B 7B 2.55 18 ADS ST-09 INLET-7B INLET-7C 7C 0.28 18 ADS *This pipe has been sized to convey the emergeny overflow from this pond. ST-05B Table C-1 Storm Sewer Summary ST-01 ST-01A ST-05 Appendix C ST-01, ST-01A, ST-01B, ST-01C 100-yr Design Storm Tailwater Elevation = 4838.59 Manhole Input Summary: Given Flow Sub Basin Information Element Name Ground Elevatio n (ft) Total Know n Flow (cfs) Local Contributio n (cfs) Drainag e Area (Ac.) Runoff Coefficien t 5yr Coefficien t Overlan d Length (ft) Overlan d Slope (%) Gutter Lengt h (ft) Gutter Velocit y (fps) FES-1A 4850.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1A 4850.87 66.29 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1B 4849.32 62.78 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1C 4846.35 62.78 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1I 4845.89 18.90 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 DUMMY NODE INLET-1B 4845.89 18.90 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1D 4849.17 30.29 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1E 4848.26 21.38 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1F 4843.00 2.70 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 DUMMY NODE OUTLET A 4843.00 2.70 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 DUMMY NODE INLET-1D 4848.26 18.70 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1G 4848.11 9.50 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 DUMMY NODE INLET-1C 4848.11 9.50 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1H 4845.89 21.80 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 DUMMY NODE INLET 1A 4845.89 21.80 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1J 4839.25 10.53 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 DUMMY NODE OUTLET STRUCTUR E POND B 4839.25 10.53 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Manhole Output Summary: Local Contribution Total Design Flow Element Name Overland Time (min) Gutter Time (min) Basin Tc (min) Intensity (in/hr) Local Contrib (cfs) Coeff. Area Intensity (in/hr) Manhole Tc (min) Peak Flow (cfs) Comment FES-1A 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1A 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 66.29 1B 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 62.78 1C 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 62.78 1I 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 18.90 Sewer Input Summary: Elevation Loss Coefficients Given Dimensions Element Name Sewer Length (ft) Downstream Invert (ft) Slope (%) Upstream Invert (ft) Mannings n Bend Loss Lateral Loss Cross Section Rise (ft or in) Span (ft or in) 1A 144.20 4834.82 0.2 4835.11 0.013 0.00 1.00 CIRCULAR 60.00 in 60.00 in 1B 538.76 4835.21 0.2 4836.29 0.013 1.32 0.00 CIRCULAR 54.00 in 54.00 in 1C 595.72 4836.39 0.2 4837.58 0.013 0.05 0.25 CIRCULAR 54.00 in 54.00 in 1I 65.46 4840.09 1.0 4840.74 0.013 1.32 0.00 CIRCULAR 24.00 in 24.00 in DUMMY NODE INLET- 1B 1.00 4840.73 1.0 4840.74 0.013 0.25 0.00 CIRCULAR 36.00 in 36.00 in 1D 543.71 4837.68 0.5 4840.40 0.013 0.05 0.25 CIRCULAR 48.00 in 48.00 in 1E 18.53 4840.50 0.5 4840.59 0.013 1.32 0.00 CIRCULAR 36.00 in 36.00 in 1F 51.30 4840.69 0.6 4841.00 0.013 0.05 0.00 CIRCULAR 18.00 1I 22.68 7.22 18.77 7.17 16.74 8.08 1.26 Supercritical 18.90 0.00 DUMMY NODE INLET-1B 66.88 9.46 16.72 5.88 13.09 8.14 1.60 Supercritical 18.90 0.00 1D 101.84 8.10 19.59 6.28 17.94 7.07 1.18 Supercritical 30.29 0.00 1E 47.29 6.69 17.83 6.12 16.98 6.52 1.10 Supercritical 21.38 0.00 1F 8.16 4.62 7.48 3.89 7.13 4.14 1.10 Pressurized 2.70 51.30 DUMMY NODE OUTLET A 8.16 4.62 7.48 3.89 7.13 4.14 1.10 Pressurized 2.70 1.00 DUMMY NODE INLET-1D 47.29 6.69 16.62 5.86 15.73 6.30 1.11 Supercritical 18.70 0.00 1G 7.45 4.21 18.00 5.38 18.00 5.38 0.00 Pressurized 9.50 78.58 DUMMY NODE INLET-1C 7.45 4.21 18.00 5.38 18.00 5.38 0.00 Pressurized 9.50 1.00 1H 22.68 7.22 20.02 7.79 18.88 8.22 1.14 Supercritical 21.80 0.00 DUMMY NODE INLET 1A 41.13 8.38 19.05 6.63 15.53 8.50 1.48 Supercritical 21.80 0.00 1J 47.29 6.69 12.33 4.92 11.54 5.38 1.14 Supercritical 10.53 0.00 DUMMY NODE OUTLET STRUCTURE POND B 47.29 6.69 12.33 4.92 11.54 5.38 1.14 Supercritical 10.53 0.00  A Froude number of 0 indicates that pressured flow occurs (adverse slope or undersized pipe).  If the sewer is not pressurized, full flow represents the maximum gravity flow in the sewer.  If the sewer is pressurized, full flow represents the pressurized flow conditions. Sewer Sizing Summary: Existing Calculated Used Element Name Peak Flow (cfs) Cross Section Rise Span Rise Span Rise Span Area (ft^2) Comment 1A 66.29 CIRCULAR 60.00 in 60.00 in 54.00 in 54.00 in 60.00 in 60.00 in 19.63 1B 62.78 CIRCULAR 54.00 in 54.00 in 48.00 in 48.00 in 54.00 in 54.00 in 15.90 DUMMY NODE OUTLET A 2.70 CIRCULAR 18.00 in 18.00 in 12.00 in 12.00 in 18.00 in 18.00 in 1.77 DUMMY NODE INLET-1D 18.70 CIRCULAR 36.00 in 36.00 in 27.00 in 27.00 in 36.00 in 36.00 in 7.07 1G 9.50 CIRCULAR 18.00 in 18.00 in 21.00 in 21.00 in 18.00 in 18.00 in 1.77 Existing height is smaller than the suggested height. Existing width is smaller than the suggested width. Exceeds max. Depth/Rise DUMMY NODE INLET-1C 9.50 CIRCULAR 18.00 in 18.00 in 21.00 in 21.00 in 18.00 in 18.00 in 1.77 Existing height is smaller 1I 4840.09 4840.74 0.74 0.00 4841.48 4842.30 4842.49 0.61 4843.10 DUMMY NODE INLET-1B 4840.73 4840.74 0.03 0.00 4842.95 4842.95 4843.13 0.00 4843.13 1D 4837.68 4840.40 0.00 0.22 4841.13 4842.03 4841.24 1.41 4842.65 1E 4840.50 4840.59 0.19 0.00 4842.57 4842.57 4842.83 0.03 4842.86 1F 4840.69 4841.00 0.00 0.00 4842.83 4842.86 4842.86 0.03 4842.90 DUMMY NODE OUTLET A 4840.99 4841.00 0.01 0.00 4842.87 4842.87 4842.91 0.00 4842.91 DUMMY NODE INLET-1D 4840.59 4840.59 0.03 0.00 4842.70 4842.70 4842.89 0.00 4842.89 1G 4840.50 4840.89 0.59 0.00 4842.79 4843.43 4843.24 0.64 4843.88 DUMMY NODE INLET-1C 4840.89 4840.89 0.11 0.00 4843.54 4843.55 4843.99 0.01 4844.00 1H 4840.08 4840.22 0.99 0.00 4841.65 4841.89 4842.70 0.13 4842.83 DUMMY NODE INLET 1A 4840.21 4840.22 0.08 0.00 4842.59 4842.59 4842.91 0.00 4842.91 1J 4836.84 4837.25 0.00 0.00 4838.92 4838.92 4838.98 0.04 4839.02 DUMMY NODE OUTLET STRUCTURE POND B 4837.25 4837.25 0.01 0.00 4838.93 4838.93 4839.03 0.00 4839.03  Bend and Lateral losses only apply when there is an outgoing sewer. The system outfall, sewer #0, is not considered a sewer.  Bend loss = Bend K * V_fi ^ 2/(2*g)  Lateral loss = V_fo ^ 2/(2*g)- Junction Loss K * V_fi ^ 2/(2*g).  Friction loss is always Upstream EGL - Downstream EGL. ST-02 100-yr Design Storm Tailwater Elevation = 4848.00 Manhole Input Summary: Given Flow Sub Basin Information Element Name Ground Elevation (ft) Total Known Flow (cfs) Local Contribution (cfs) Drainage Area (Ac.) Runoff Coefficient 5yr Coefficient Overland Length (ft) Overland Slope (%) Gutter Length (ft) Gutter Velocity (fps) FES-2A 4842.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2A 4849.79 32.95 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 DUMMY NODE INLET-2A 4849.79 32.95 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Manhole Output Summary: Local Contribution Total Design Flow Element Name Overland Time (min) Gutter Time (min) Basin Tc (min) Intensity (in/hr) Local Contrib (cfs) Sewer Input Summary: Elevation Loss Coefficients Given Dimensions Element Name Sewer Length (ft) Downstream Invert (ft) Slope (%) Upstream Invert (ft) Mannings n Bend Loss Lateral Loss Cross Section Rise (ft or in) Span (ft or in) 2A 56.93 4844.00 0.5 4844.28 0.013 0.03 0.00 CIRCULAR 36.00 in 36.00 in DUMMY NODE INLET-2A 1.00 4844.28 0.5 4844.28 0.013 0.25 0.00 CIRCULAR 36.00 in 36.00 in Sewer Flow Summary: Full Flow Capacity Critical Flow Normal Flow Element Name Flow (cfs) Velocity (fps) Depth (in) Velocity (fps) Depth (in) Velocity (fps) Froude Number Flow Condition Flow (cfs) Surcharged Length (ft) Comment 2A 47.29 6.69 22.36 7.14 22.13 7.23 1.02 Pressurized 32.95 56.93 Grade Line Summary: Tailwater Elevation (ft): 4848.00 Invert Elev. Downstream Manhole Losses HGL EGL Element Name Downstream (ft) Upstream (ft) Bend Loss (ft) Lateral Loss (ft) Downstream (ft) Upstream (ft) Downstream (ft) Friction Loss (ft) Upstream (ft) 2A 4844.00 4844.28 0.00 0.00 4848.00 4848.14 4848.34 0.14 4848.48 DUMMY NODE INLET-2A 4844.28 4844.28 0.08 0.00 4848.22 4848.22 4848.56 0.00 4848.56  Bend and Lateral losses only apply when there is an outgoing sewer. The system outfall, sewer #0, is not considered a sewer.  Bend loss = Bend K * V_fi ^ 2/(2*g)  Lateral loss = V_fo ^ 2/(2*g)- Junction Loss K * V_fi ^ 2/(2*g).  Friction loss is always Upstream EGL - Downstream EGL. ST-03 100-yr Design Storm Tailwater Elevation = 4848.00 Manhole Input Summary: Given Flow Sub Basin Information Element Name Ground Elevation (ft) Total Known Flow (cfs) Local Contribution (cfs) Drainage Area (Ac.) Runoff Coefficient 5yr Coefficient Overland Length (ft) Overland Slope (%) Gutter Length (ft) Gutter Velocity (fps) FES-3A 4848.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 B1 4852.68 14.17 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 DUMMY NODE 4852.68 14.17 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Manhole Output Summary: Local Contribution Total Design Flow Element Name Overland Time (min) Gutter Time (min) Basin Tc (min) Intensity (in/hr) Local Contrib (cfs) Coeff. Area Intensity Sewer Input Summary: Elevation Loss Coefficients Given Dimensions Element Name Sewer Length (ft) Downstream Invert (ft) Slope (%) Upstream Invert (ft) Mannings n Bend Loss Lateral Loss Cross Section Rise (ft or in) Span (ft or in) B1 60.69 4846.00 0.5 4846.30 0.013 0.03 0.00 CIRCULAR 24.00 in 24.00 in DUMMY NODE 1.00 4846.30 0.5 4846.30 0.013 0.25 0.00 CIRCULAR 24.00 in 24.00 in Sewer Flow Summary: Full Flow Capacity Critical Flow Normal Flow Element Name Flow (cfs) Velocity (fps) Depth (in) Velocity (fps) Depth (in) Velocity (fps) Froude Number Flow Condition Flow (cfs) Surcharged Length (ft) Comment B1 16.04 5.11 16.27 6.25 17.53 5.76 0.86 Subcritical Surcharged 14.17 3.14 DUMMY NODE 16.04 5.11 16.27 6.25 17.53 5.76 0.86 Pressurized 14.17 1.00 Grade Line Summary: Tailwater Elevation (ft): 4848.00 Invert Elev. Downstream Manhole Losses HGL EGL Element Name Downstream (ft) Upstream (ft) Bend Loss (ft) Lateral Loss (ft) Downstream (ft) Upstream (ft) Downstream (ft) Friction Loss (ft) Upstream (ft) B1 4846.00 4846.30 0.00 0.00 4848.00 4848.21 4848.32 0.22 4848.54 DUMMY NODE 4846.30 4846.30 0.08 0.00 4848.30 4848.30 4848.62 0.00 4848.62  Bend and Lateral losses only apply when there is an outgoing sewer. The system outfall, sewer #0, is not considered a sewer.  Bend loss = Bend K * V_fi ^ 2/(2*g)  Lateral loss = V_fo ^ 2/(2*g)- Junction Loss K * V_fi ^ 2/(2*g).  Friction loss is always Upstream EGL - Downstream EGL. ST-05, ST-05A, ST-05B 100-yr Design Storm Tailwater Elevation = 4846.00 Manhole Input Summary: Given Flow Sub Basin Information Element Name Ground Elevation (ft) Total Known Flow (cfs) Local Contribution (cfs) Drainage Area (Ac.) Runoff Coefficient 5yr Coefficient Overland Length (ft) Overland Slope (%) Gutter Length (ft) Gutter Velocity (fps) FES-5A 4846.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5A 4848.09 56.56 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5F 4847.75 1.77 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5G 4848.50 0.89 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 DUMMY NODE INLET-5E 4848.50 0.89 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 DUMMY NODE INLET-5D 4847.75 0.89 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5B 4850.03 45.81 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5C 4849.71 45.81 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5E 4849.39 9.61 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 DUMMY NODE INLET-5C 4849.39 9.61 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5D 4848.59 37.53 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 DUMMY NODE INLET -5B 4848.59 37.53 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 DUMMY NODE INLET-5A 4848.09 11.42 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Manhole Output Summary: Local Contribution Total Design Flow Element Name Overland Time (min) Gutter Time (min) Basin Tc (min) Intensity (in/hr) Local Contrib (cfs) Coeff. Area Intensity (in/hr) Manhole Tc (min) Peak Flow (cfs) Comment FES-5A 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5A 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 56.56 5F 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.77 5G 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.89 DUMMY NODE INLET- 5E 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.89 DUMMY NODE INLET- 5D 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.89 5B 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 45.81 5C 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 45.81 5E 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 9.61 DUMMY NODE INLET- 5C 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 9.61 5D 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 37.53 DUMMY NODE INLET - 5F 112.04 4843.86 0.6 4844.53 0.013 1.32 0.00 CIRCULAR 18.00 in 18.00 in 5G 74.32 4844.63 0.5 4845.00 0.013 1.32 0.00 CIRCULAR 18.00 in 18.00 in DUMMY NODE INLET-5E 1.00 4845.00 0.5 4845.00 0.013 0.25 0.00 CIRCULAR 18.00 in 18.00 in DUMMY NODE INLET-5D 1.00 4844.52 0.6 4844.53 0.013 0.25 0.00 CIRCULAR 18.00 in 18.00 in 5B 205.53 4841.39 0.5 4842.42 0.013 0.05 0.25 CIRCULAR 48.00 in 48.00 in 5C 106.50 4842.52 0.5 4843.05 0.013 0.05 0.25 CIRCULAR 48.00 in 48.00 in 5E 64.06 4843.15 0.5 4843.47 0.013 1.32 0.00 CIRCULAR 36.00 in 36.00 in DUMMY NODE INLET-5C 1.00 4844.89 0.5 4844.89 0.013 0.25 0.00 CIRCULAR 36.00 in 36.00 in 5D 103.17 4843.15 0.5 4843.67 0.013 0.05 0.25 CIRCULAR 36.00 in 36.00 in DUMMY NODE INLET -5B 1.00 4843.67 0.5 4843.67 0.013 0.25 0.00 CIRCULAR 36.00 in 36.00 in DUMMY NODE INLET-5A 1.00 4841.29 0.5 4841.29 0.013 0.25 0.00 CIRCULAR 48.00 in 48.00 in Sewer Flow Summary: Full Flow Capacity Critical Flow Normal Flow Element Name Flow DUMMY NODE INLET- 5A 101.84 8.10 11.83 4.74 10.85 5.36 1.18 Pressurized 11.42 1.00  A Froude number of 0 indicates that pressured flow occurs (adverse slope or undersized pipe).  If the sewer is not pressurized, full flow represents the maximum gravity flow in the sewer.  If the sewer is pressurized, full flow represents the pressurized flow conditions. Sewer Sizing Summary: Existing Calculated Used Element Name Peak Flow (cfs) Cross Section Rise Span Rise Span Rise Span Area (ft^2) Comment 5A 56.56 CIRCULAR 48.00 in 48.00 in 42.00 in 42.00 in 48.00 in 48.00 in 12.57 5F 1.77 CIRCULAR 18.00 in 18.00 in 12.00 in 12.00 in 18.00 in 18.00 in 1.77 5G 0.89 CIRCULAR 18.00 in 18.00 in 12.00 in 12.00 in 18.00 in 18.00 in 1.77 DUMMY NODE INLET-5E 0.89 CIRCULAR 18.00 in 18.00 in 12.00 in 12.00 in 18.00 in 18.00 in 1.77 DUMMY NODE INLET-5D 0.89 CIRCULAR 18.00 in 18.00 in 12.00 in 12.00 in 18.00 in 18.00 in 1.77 5B 45.81 CIRCULAR 48.00 in 48.00 in 36.00 in 36.00 in 48.00 in 48.00 in 12.57 5C 45.81 CIRCULAR 48.00 in 48.00 in 36.00 in 36.00 in 48.00 in 48.00 in 12.57 5E 9.61 CIRCULAR 36.00 in 36.00 in 21.00 in 21.00 in 36.00 in 36.00 in 7.07 DUMMY NODE INLET-5C 9.61 CIRCULAR 36.00 in 36.00 in 21.00 in 21.00 in 36.00 in 36.00 in 7.07 5D 37.53 CIRCULAR 36.00 in 36.00 in 36.00 in 36.00 in 36.00 in 36.00 in 7.07 DUMMY NODE INLET -5B 37.53 CIRCULAR 36.00 in 36.00 in 36.00 in 36.00 in 36.00 in 36.00 in 7.07 DUMMY NODE INLET-5A 11.42 CIRCULAR 48.00 in 48.00 in 24.00 in 24.00 in 48.00 in 48.00 in 12.57  Calculated diameter was determined by sewer hydraulic capacity rounded up to the nearest commercially available size.  Sewer sizes should not decrease downstream.  All hydraulics where calculated using the 'Used' parameters. Grade Line Summary: Tailwater Elevation (ft): 4846.00 Invert Elev. Downstream Manhole Losses HGL EGL Element Name Downstream (ft) Upstream (ft) Bend Loss (ft) Lateral Loss (ft) Downstream (ft) Upstream (ft) Downstream (ft) Friction DUMMY NODE INLET-5E 4845.00 4845.00 0.00 0.00 4846.59 4846.59 4846.59 0.00 4846.59 DUMMY NODE INLET-5D 4844.52 4844.53 0.00 0.00 4846.58 4846.58 4846.58 0.00 4846.58 5B 4841.39 4842.42 0.01 0.26 4846.59 4846.80 4846.80 0.21 4847.01 5C 4842.52 4843.05 0.01 0.15 4846.97 4847.07 4847.17 0.11 4847.28 5E 4843.15 4843.47 0.04 0.00 4847.29 4847.30 4847.32 0.01 4847.33 DUMMY NODE INLET-5C 4844.89 4844.89 0.01 0.00 4847.31 4847.31 4847.35 0.00 4847.35 5D 4843.15 4843.67 0.02 0.10 4847.19 4847.52 4847.63 0.32 4847.96 DUMMY NODE INLET -5B 4843.67 4843.67 0.11 0.00 4847.63 4847.63 4848.07 0.00 4848.07 DUMMY NODE INLET-5A 4841.29 4841.29 0.00 0.00 4846.52 4846.52 4846.53 0.00 4846.53  Bend and Lateral losses only apply when there is an outgoing sewer. The system outfall, sewer #0, is not considered a sewer.  Bend loss = Bend K * V_fi ^ 2/(2*g)  Lateral loss = V_fo ^ 2/(2*g)- Junction Loss K * V_fi ^ 2/(2*g).  Friction loss is always Upstream EGL - Downstream EGL. ST-06 100-yr Design Storm Tailwater Elevation = 4846.00 Manhole Input Summary: Given Flow Sub Basin Information Element Name Ground Elevation (ft) Total Known Flow (cfs) Local Contribution (cfs) Drainage Area (Ac.) Runoff Coefficient 5yr Coefficient Overland Length (ft) Overland Slope (%) Gutter Length (ft) Gutter Velocity (fps) FES-6A 4842.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 6A 4850.31 12.30 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 DUMMY NODE INLET-6A 4850.31 12.30 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Manhole Output Summary: Local Contribution Total Design Flow Element Name Overland Time (min) Gutter Time (min) Basin Tc (min) Intensity (in/hr) Local Contrib (cfs) Sewer Input Summary: Elevation Loss Coefficients Given Dimensions Element Name Sewer Length (ft) Downstream Invert (ft) Slope (%) Upstream Invert (ft) Mannings n Bend Loss Lateral Loss Cross Section Rise (ft or in) Span (ft or in) 6A 80.56 4840.00 0.5 4840.40 0.013 0.03 0.00 CIRCULAR 24.00 in 24.00 in DUMMY NODE INLET-6A 1.00 4840.40 0.5 4840.40 0.013 0.25 0.00 CIRCULAR 24.00 in 24.00 in Sewer Flow Summary: Full Flow Capacity Critical Flow Normal Flow Element Name Flow (cfs) Velocity (fps) Depth (in) Velocity (fps) Depth (in) Velocity (fps) Froude Number Flow Condition Flow (cfs) Surcharged Length (ft) Comment 6A 16.04 5.11 15.12 5.90 15.75 5.63 0.92 Pressurized 12.30 80.56 Grade Line Summary: Tailwater Elevation (ft): 4846.00 Invert Elev. Downstream Manhole Losses HGL EGL Element Name Downstream (ft) Upstream (ft) Bend Loss (ft) Lateral Loss (ft) Downstream (ft) Upstream (ft) Downstream (ft) Friction Loss (ft) Upstream (ft) 6A 4840.00 4840.40 0.00 0.00 4846.00 4846.24 4846.24 0.24 4846.47 DUMMY NODE INLET-6A 4840.40 4840.40 0.06 0.00 4846.30 4846.30 4846.53 0.00 4846.54  Bend and Lateral losses only apply when there is an outgoing sewer. The system outfall, sewer #0, is not considered a sewer.  Bend loss = Bend K * V_fi ^ 2/(2*g)  Lateral loss = V_fo ^ 2/(2*g)- Junction Loss K * V_fi ^ 2/(2*g).  Friction loss is always Upstream EGL - Downstream EGL. ST-07 100-yr Design Storm Tailwater Elevation = 4848.00 Manhole Input Summary: Given Flow Sub Basin Information Element Name Ground Elevation (ft) Total Known Flow (cfs) Local Contribution (cfs) Drainage Area (Ac.) Runoff Coefficient 5yr Coefficient Overland Length (ft) Overland Slope (%) Gutter Length (ft) Gutter Velocity (fps) FES-7A 4848.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 7A 4851.50 8.73 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 7B 4851.75 2.55 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 DUMMY NODE INLET-7B 4851.75 2.27 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 7C 4852.00 0.28 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 DUMMY NODE INLET-7C 4852.00 0.28 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 DUMMY NODE INLET-7A 4851.50 6.18 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Manhole Output Summary: Local Contribution Total Design Flow Element Name Overland Time (min) Gutter Time (min) Basin Tc (min) Intensity (in/hr) Local Contrib (cfs) Coeff. Area Intensity (in/hr) Manhole Tc (min) Peak Flow (cfs) Comment FES-7A 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 7A 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 8.73 Surface Water Present (Downstream) 7B 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2.55 DUMMY NODE INLET-7B 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2.27 7C 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.28 DUMMY NODE INLET-7C 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.28 DUMMY NODE INLET-7A 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 6.18 Sewer Input Summary: Elevation Loss Coefficients Given Dimensions Element Name Sewer Length (ft) Downstream Invert (ft) Slope (%) Upstream Invert (ft) Mannings n Bend Loss Lateral 7C 7.45 4.21 2.34 2.08 2.39 2.02 0.96 Subcritical 0.28 0.00 DUMMY NODE INLET-7C 7.45 4.21 2.34 2.08 2.39 2.02 0.96 Subcritical 0.28 0.00 DUMMY NODE INLET-7A 16.04 5.11 10.55 4.65 10.34 4.77 1.04 Supercritical 6.18 0.00  A Froude number of 0 indicates that pressured flow occurs (adverse slope or undersized pipe).  If the sewer is not pressurized, full flow represents the maximum gravity flow in the sewer.  If the sewer is pressurized, full flow represents the pressurized flow conditions. Sewer Sizing Summary: Existing Calculated Used Element Name Peak Flow (cfs) Cross Section Rise Span Rise Span Rise Span Area (ft^2) Comment 7A 8.73 CIRCULAR 24.00 in 24.00 in 21.00 in 21.00 in 24.00 in 24.00 in 3.14 7B 2.55 CIRCULAR 18.00 in 18.00 in 15.00 in 15.00 in 18.00 in 18.00 in 1.77 DUMMY NODE INLET-7B 2.27 CIRCULAR 18.00 in 18.00 in 12.00 in 12.00 in 18.00 in 18.00 in 1.77 7C 0.28 CIRCULAR 18.00 in 18.00 in 12.00 in 12.00 in 18.00 in 18.00 in 1.77 DUMMY NODE INLET-7C 0.28 CIRCULAR 18.00 in 18.00 in 12.00 in 12.00 in 18.00 in 18.00 in 1.77 DUMMY NODE INLET-7A 6.18 CIRCULAR 24.00 in 24.00 in 18.00 in 18.00 in 24.00 in 24.00 in 3.14  Calculated diameter was determined by sewer hydraulic capacity rounded up to the nearest commercially available size.  Sewer sizes should not decrease downstream.  All hydraulics where calculated using the 'Used' parameters. Grade Line Summary: Tailwater Elevation (ft): 4848.00 Invert Elev. Downstream Manhole Losses HGL EGL Element Name Downstream (ft) Upstream (ft) Bend Loss (ft) Lateral Loss (ft) Downstream (ft) Upstream (ft) Downstream (ft) Friction Loss (ft) Upstream (ft) 7A 4847.00 4848.23 0.00 0.00 4848.05 4849.28 4848.47 1.23 4849.70 DUMMY NODE INLET-7A 4848.23 4848.23 0.02 0.00 4849.61 4849.61 4849.72 0.00 4849.72  Bend and Lateral losses only apply when there is an outgoing sewer. The system outfall, sewer #0, is not considered a sewer.  Bend loss = Bend K * V_fi ^ 2/(2*g)  Lateral loss = V_fo ^ 2/(2*g)- Junction Loss K * V_fi ^ 2/(2*g).  Friction loss is always Upstream EGL - Downstream EGL. APPENDIX D Channel Design H23 Final Drainage Report Channel ID 10-yr Design Flow (cfs) 100-yr Design Flow (cfs) Slope (%) Bottom Width (ft) Side Slope (H:V) Flow Depth (ft) Max Velocity (fps) Temporary or Permanent? Protection Required? A-A 4.63 12.26 2.00% 0 4 0.94 3.47 Permanent No Curb Cut #1 1.33 3.72 2.00% 2 Vertical 0.31 6.00 Permanent No Curb Cut #2 0.37 0.95 2.00% 2 Vertical 0.22 4.32 Permanent No *Sidewalk Chase #1 4.63 12.26 2.00% 2 Vertical **0.36 **6.43 Permanent Riprap Rundown Hydroflow Express Extension for Autodesk Civil 3D was used for all calculations. *The 100-yr design strom for this sidewalk chase will overtop the sidewalk and spill directly into the pond. **Represents the 10-yr design storm. Table D-1 Channel Summary Appendix D Channel Report Hydraflow Express Extension for Autodesk® AutoCAD® Civil 3D® by Autodesk, Inc. Saturday, Feb 25 2017 H23 - Swale A Triangular Side Slopes (z:1) = 4.00, 4.00 Total Depth (ft) = 3.00 Invert Elev (ft) = 100.00 Slope (%) = 2.00 N-Value = 0.035 Calculations Compute by: Known Q Known Q (cfs) = 12.26 Highlighted Depth (ft) = 0.94 Q (cfs) = 12.26 Area (sqft) = 3.53 Velocity (ft/s) = 3.47 Wetted Perim (ft) = 7.75 Crit Depth, Yc (ft) = 0.90 Top Width (ft) = 7.52 EGL (ft) = 1.13 0 5 10 15 20 25 30 35 Elev (ft) Section Depth (ft) 99.00 -1.00 100.00 0.00 101.00 1.00 102.00 2.00 103.00 3.00 104.00 4.00 Reach (ft) Channel Report Hydraflow Express Extension for Autodesk® AutoCAD® Civil 3D® by Autodesk, Inc. Monday, Feb 27 2017 Curb Cut #1 Rectangular Bottom Width (ft) = 2.00 Total Depth (ft) = 0.50 Invert Elev (ft) = 100.00 Slope (%) = 2.00 N-Value = 0.013 Calculations Compute by: Known Q Known Q (cfs) = 3.72 Highlighted Depth (ft) = 0.31 Q (cfs) = 3.720 Area (sqft) = 0.62 Velocity (ft/s) = 6.00 Wetted Perim (ft) = 2.62 Crit Depth, Yc (ft) = 0.48 Top Width (ft) = 2.00 EGL (ft) = 0.87 0 .5 1 1.5 2 2.5 3 Elev (ft) Section Depth (ft) 99.75 -0.25 100.00 0.00 100.25 0.25 100.50 0.50 100.75 0.75 101.00 1.00 Reach (ft) Channel Report Hydraflow Express Extension for Autodesk® AutoCAD® Civil 3D® by Autodesk, Inc. Monday, Feb 27 2017 Curb Cut #2 Rectangular Bottom Width (ft) = 1.00 Total Depth (ft) = 0.50 Invert Elev (ft) = 100.00 Slope (%) = 2.00 N-Value = 0.013 Calculations Compute by: Known Q Known Q (cfs) = 0.95 Highlighted Depth (ft) = 0.22 Q (cfs) = 0.950 Area (sqft) = 0.22 Velocity (ft/s) = 4.32 Wetted Perim (ft) = 1.44 Crit Depth, Yc (ft) = 0.31 Top Width (ft) = 1.00 EGL (ft) = 0.51 0 .25 .5 .75 1 1.25 1.5 Elev (ft) Section Depth (ft) 99.75 -0.25 100.00 0.00 100.25 0.25 100.50 0.50 100.75 0.75 101.00 1.00 Reach (ft) Channel Report Hydraflow Express Extension for Autodesk® AutoCAD® Civil 3D® by Autodesk, Inc. Monday, Feb 27 2017 Sidewalk Chase #1 Rectangular Bottom Width (ft) = 2.00 Total Depth (ft) = 0.50 Invert Elev (ft) = 100.00 Slope (%) = 2.00 N-Value = 0.013 Calculations Compute by: Known Q Known Q (cfs) = 4.63 Highlighted Depth (ft) = 0.36 Q (cfs) = 4.630 Area (sqft) = 0.72 Velocity (ft/s) = 6.43 Wetted Perim (ft) = 2.72 Crit Depth, Yc (ft) = 0.50 Top Width (ft) = 2.00 EGL (ft) = 1.00 0 .5 1 1.5 2 2.5 3 Elev (ft) Section Depth (ft) 99.75 -0.25 100.00 0.00 100.25 0.25 100.50 0.50 100.75 0.75 101.00 1.00 Reach (ft) Weir Report Hydraflow Express Extension for Autodesk® AutoCAD® Civil 3D® by Autodesk, Inc. Tuesday, Feb 28 2017 9.0-cfs Weir Crest Rectangular Weir Crest = Broad Bottom Length (ft) = 14.65 Total Depth (ft) = 0.35 Calculations Weir Coeff. Cw = 2.97 Compute by: Known Depth Known Depth (ft) = 0.35 Highlighted Depth (ft) = 0.35 Q (cfs) = 9.009 Area (sqft) = 5.13 Velocity (ft/s) = 1.76 Top Width (ft) = 14.65 0 2 4 6 8 10 12 14 16 18 20 Depth (ft) 9.0-cfs Weir Crest Depth (ft) -0.50 -0.50 0.00 0.00 0.50 0.50 1.00 1.00 Weir W.S. Length (ft) Weir Report Hydraflow Express Extension for Autodesk® AutoCAD® Civil 3D® by Autodesk, Inc. Tuesday, Feb 28 2017 Emergency Overflow Gravel Pond #2 Rectangular Weir Crest = Broad Bottom Length (ft) = 120.00 Total Depth (ft) = 1.04 Calculations Weir Coeff. Cw = 2.97 Compute by: Known Q Known Q (cfs) = 180.00 Highlighted Depth (ft) = 0.63 Q (cfs) = 180.00 Area (sqft) = 76.09 Velocity (ft/s) = 2.37 Top Width (ft) = 120.00 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 Depth (ft) Emergency Overflow Gravel Pond #2 Depth (ft) -0.50 -0.50 0.00 0.00 0.50 0.50 1.00 1.00 1.50 1.50 2.00 2.00 Weir W.S. Length (ft) APPENDIX E Riprap Design H23 Final Drainage Report Storm Flow Velocity Pipe Depth @ Depth in Froude Minimum Expansion Extra Length Length Width Riprap Sewer Dia. Outlet Pipe # Yt/D c or Q/D 1.5 or Q/D 2.5 or Da = (Dc+Y n)/2 Yt /Da or Q/D a 1.5 or Q/Da 2.5 or Diameter Factor if Q/Da 2.5 Lp W p Type (cfs) (fps) (ft) Yt (ft) Yn (ft) Y t/H Q/WH 0.5 Q/WH 1.5 (ft) Yt /Ha Q/WH a 0.5 Q/WHa 1.5 d50 (ft) 1/(2Tanθ) > 6 (ft) (ft) ST-01 66.29 6.14 5.0 3.77 2.70 0.73 0.75 5.93 1.19 0.19 6.7 0.00 15.00 20.0 TYPE L ST-02 32.95 7.23 3.0 4.00 1.84 1.02 2.42 1.65 8.74 3.61 0.18 6.7 0.00 9.00 12.0 TYPE L ST-03 14.17 5.76 2.0 2.00 1.46 0.86 1.00 5.01 2.51 0.12 6.7 0.00 6.00 8.0 TYPE L ST-05 56.56 8.32 4.0 5.40 2.13 1.12 3.06 1.76 10.54 3.44 0.22 6.7 0.00 12.00 16.0 TYPE L ST-06 12.30 5.63 2.0 6.00 1.31 0.92 3.00 4.35 2.17 0.03 6.7 0.00 6.00 8.0 TYPE L ST-07 8.73 5.21 2.0 1.00 1.05 1.00 1.53 0.66 4.63 3.03 0.32 6.7 0.00 6.00 8.0 TYPE L Figures and equations from Urban Drainage & Flood Control District, Urban Drainage Criteria Manual, Volume 1, Major Drainage, 2001 (Froude # < 1, Subcritical Flow) (Froude # > 1, Supercritical Flow ) Table E-1 Riprap Design Appendix E APPENDIX F Detention Pond Design H23 Final Drainage Report 100-yr Detention Volume (ac-ft) Pond A 9.76 0.18 0.21 2.27 2.45 2.53 1.61 N/A 4844.33 4848.00 Pond B 11.52 0.20 0.22 2.60 2.80 3.46 1.90 N/A 4842.25 4846.00 "U" Basins Added to Ex. Gravel Pond #2 5.69 Waived N/A 1.50 N/A N/A 0.94 4837.12 N/A 4837.74 2-yr Historic Release Rate (cfs) Total Contributing Area Provided Required Provided Pond ID Water Quality Capture Volume (WQCV) (ac-ft) Required Note: The release rate for "U" Basins was determined based on the area multiplied the allowable release rate per acre. This release rate was used in a mass-balance spreadsheet to determine the 100-yr storage volume for those basins. This number was then added to the total storage required for the Convenience Shopping Center Report. Table F-1 Detention Pond Summary Table Required 100-yr WSEL (ft) Groundwater WSEL (ft) Total Volume (100-yr + WQCV) (ac-ft) Water Quality WSEL (ft) H23 Final Drainage Report Detention Requirements Pond A - Major Storm (100-yr) Mass Balance Method 0.76 1.61 cfs 9.76 acres Detention Requirements 1.89 acre-feet City of Fort Collins criteria (120%) 2.27 acre-feet Time (min) Intensity (in/hr) Qin (cfs) Volume in (ft 3 ) Qout (cfs) Volumeout (ft 3 ) Volume detained (acre-feet) 5 9.95 73.805 22,141.54 1.61 483 0.497 10 7.72 57.264 34,358.32 1.61 966 0.767 15 6.52 48.363 43,526.48 1.61 1,449 0.966 20 5.60 41.539 49,846.27 1.61 1,932 1.100 25 4.98 36.940 55,409.47 1.61 2,416 1.217 30 4.52 33.528 60,349.59 1.61 2,899 1.319 35 4.08 30.264 63,554.00 1.61 3,382 1.381 40 3.74 27.742 66,580.38 1.61 3,865 1.440 45 3.46 25.665 69,295.22 1.61 4,348 1.491 50 3.23 23.959 71,876.54 1.61 4,831 1.539 55 3.03 22.475 74,168.58 1.61 5,314 1.581 60 2.86 21.214 76,371.61 1.61 5,797 1.620 65 2.70 20.028 78,107.33 1.61 6,281 1.649 70 2.60 19.286 81,000.19 1.61 6,764 1.704 75 2.50 18.544 83,448.00 1.61 7,247 1.749 80 2.40 17.802 85,450.75 1.61 7,730 1.784 85 2.30 17.060 87,008.45 1.61 8,213 1.809 90 2.20 16.319 88,121.09 1.61 8,696 1.823 100 2.05 15.206 91,236.48 1.61 9,662 1.873 110 1.90 14.093 93,016.70 1.61 10,629 1.891 120 1.75 12.981 93,461.76 1.61 11,595 1.879 130 1.60 11.868 92,571.65 1.61 12,561 1.837 140 1.40 10.385 87,230.98 1.61 13,527 1.692 150 1.20 8.901 80,110.08 1.61 14,494 1.506 160 1.15 8.530 81,890.30 1.61 15,460 1.525 170 1.10 8.159 83,225.47 1.61 16,426 1.534 180 1.05 7.788 84,115.58 1.61 17,392 1.532 Runoff Coefficient, C = 2-yr Release, Qout = Area = Appendix F H23 Final Drainage Report % Imperviousness 54.42% WQCV (inches)* =a(0.91i 3 -1.19i 2 +0.78i) 0.22 inches Volume = (WQCV/12)xA 0.18 ac-ft *WQCV in 40-hr drain time a=1.0 from Figure 3-2. Water Quality Capture Volume (WQCV) Based on BMP Drain Time UDFCD Storm Drainage Criteria Manual Volume 3 Table F-2 Water Quality Capture Volume (WQCV) Pond A Appendix F Project: Basin ID: Design Information (Input): Width of Basin Bottom, W = ft Right Triangle OR… Length of Basin Bottom, L = ft Isosceles Triangle OR… Dam Side-slope (H:V), Zd = ft/ft Rectangle OR… Circle / Ellipse OR… Irregular X (Use Overide values in cells G32:G52) MINOR MAJOR Storage Requirement from Sheet 'Modified FAA': acre-ft. Stage-Storage Relationship: Storage Requirement from Sheet 'Hydrograph': acre-ft. Storage Requirement from Sheet 'Full-Spectrum': acre-ft. Labels Water Side Basin Basin Surface Surface Volume Surface Volume Target Volumes for WQCV, Minor, Surface Slope Width at Length at Area at Area at Below Area at Below for WQCV, Minor, & Major Storage Elevation (H:V) Stage Stage Stage Stage Stage Stage Stage & Major Storage Stages ft ft/ft ft ft ft 2 ft 2 User ft 3 acres acre-ft Volumes (input) (input) Below El. (output) (output) (output) Overide (output) (output) (output) (for goal seek) 4843.00 (input) 1,419 0 0.033 0.000 4844.00 4.00 0.00 0.00 10,055 5,737 0.231 0.132 WQCV 4844.33 4.00 0.00 0.00 10,412 9,114 0.239 0.209 4845.00 4.00 0.00 0.00 22,668 20,196 0.520 0.464 4846.00 4.00 0.00 0.00 27,867 45,463 0.640 1.044 4847.00 4.00 0.00 0.00 32,126 75,460 0.738 1.732 100-yr + WQCV 4848.00 4.00 0.00 0.00 36,891 109,968 0.847 2.525 4849.00 4.00 0.00 0.00 43,335 150,081 0.995 3.445 Box Elder Ditch 4849.20 4.00 0.00 0.00 44,045 158,819 1.011 3.646 #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A Project: Basin ID: STAGE-STORAGE SIZING FOR DETENTION BASINS 4843.00 4844.00 4845.00 4846.00 4847.00 4848.00 4849.00 4850.00 0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 4.00 Stage (ft. elev.) Storage (acre-feet) STAGE-STORAGE CURVE FOR THE POND UD Detention Pond A VolCalc, Basin 2/24/2017, 1:43 PM Project: Basin ID: WQCV Design Volume (Input): Catchment Imperviousness, Ia = 54.4 percent Catchment Area, A = 9.76 acres Diameter of holes, D = 0.953 inches Depth at WQCV outlet above lowest perforation, H = 1 feet Number of holes per row, N = 1 Vertical distance between rows, h = 4.00 inches OR Number of rows, NL = 3.00 Orifice discharge coefficient, Co = 0.65 Height of slot, H = inches Slope of Basin Trickle Channel, S = 0.005 ft / ft Width of slot, W = inches Time to Drain the Pond = 40 hours Watershed Design Information (Input): 1.33 Percent Soil Type A = 20 % Percent Soil Type B = 49 % Percent Soil Type C/D = 31 % Outlet Design Information (Output): Water Quality Capture Volume, WQCV = 0.257 watershed inches Water Quality Capture Volume (WQCV) = 0.209 acre-feet 0.00 Design Volume (WQCV / 12 * Area * 1.2) Vol = 0.251 acre-feet Outlet area per row, Ao = 0.71 square inches Total opening area at each row based on user-input above, Ao = 0.71 square inches Total opening area at each row based on user-input above, Ao = 0.005 square feet 3 Row 1 Row 2 Row 3 Row 4 Row 5 Row 6 Row 7 Row 8 Row 9 Row 10 Row 11 Row 12 Row 13 Row 14 Row 15 Row 16 Row 17 Row 18 Row 19 Row 20 Row 21 Row 22 Row 23 Row 23  0.00 0.33 0.67 Flow 0.00 0.0000 0.0000 0.0000 0.00 0.20 0.0116 0.0000 0.0000 0.01 0.40 0.0163 0.0068 0.0000 0.02 0.60 0.0200 0.0134 0.0000 0.03 0.80 0.0231 0.0177 0.0093 0.05 1.00 0.0258 0.0212 0.0148 0.06 1.20 0.0283 0.0241 0.0188 0.07 1.40 0.0306 0.0267 0.0221 0.08 1.60 0.0327 0.0291 0.0249 0.09 1.80 0.0347 0.0313 0.0275 0.09 2.00 0.0365 0.0334 0.0298 0.10 2.20 0.0383 0.0353 0.0320 0.11 2.40 0.0400 0.0372 0.0340 0.11 2.60 0.0417 0.0389 0.0359 0.12 2.80 0.0432 0.0406 0.0377 0.12 3.00 0.0448 0.0422 0.0394 0.13 3.20 0.0462 0.0438 0.0411 0.13 3.40 0.0476 0.0453 0.0427 0.14 3.60 0.0490 0.0467 0.0442 0.14 3.80 0.0504 0.0481 0.0457 0.14 #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A Worksheet Protected Project: Basin ID: STAGE-DISCHARGE SIZING OF THE WATER QUALITY CAPTURE VOLUME (WQCV) OUTLET H23 Pond A 0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 4.00 0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 0.16 Stage (feet, elev.) Discharge (cfs) STAGE-DISCHARGE CURVE FOR THE WQCV OUTLET STRUCTURE UD Detention Pond A VolCalc, WQCV 2/24/2017, 2:04 PM Project: Basin ID: X 1 #1 Vertical #2 Vertical Sizing the Restrictor Plate for Circular Vertical Orifices or Pipes (Input) Orifice Orifice Water Surface Elevation at Design Depth Elev: WS = 4,848.00 feet Pipe/Vertical Orifice Entrance Invert Elevation Elev: Invert = 4,843.00 feet Required Peak Flow through Orifice at Design Depth Q = 1.61 cfs Pipe/Vertical Orifice Diameter (inches) Dia = 18.0 inches Orifice Coefficient Co = 0.65 Full-flow Capacity (Calculated) Full-flow area Af = 1.77 sq ft Half Central Angle in Radians Theta = 3.14 rad Full-flow capacity Qf = 19.0 cfs Percent of Design Flow = 1180% Calculation of Orifice Flow Condition Half Central Angle (0<Theta<3.1416) Theta = 0.75 rad Flow area Ao = 0.14 sq ft Top width of Orifice (inches) To = 12.23 inches Height from Invert of Orifice to Bottom of Plate (feet) Yo = 0.20 feet Elevation of Bottom of Plate Elev Plate Bottom Edge = 4,843.20 feet Resultant Peak Flow Through Orifice at Design Depth Qo = 1.6 cfs Width of Equivalent Rectangular Vertical Orifice Equivalent Width = 0.70 feet Centroid Elevation of Equivalent Rectangular Vertical Orifice Equiv. Centroid El. = 4,843.10 feet H23 Pond A RESTRICTOR PLATE SIZING FOR CIRCULAR VERTICAL ORIFICES UD Detention Pond A VolCalc, Restrictor Plate 2/24/2017, 2:05 PM H23 Final Drainage Report Detention Requirements Pond B - Major Storm (100-yr) Mass Balance Method 0.74 1.90 cfs 11.52 acres Detention Requirements 2.17 acre-feet City of Fort Collins criteria (120%) 2.60 acre-feet Time (min) Intensity (in/hr) Qin (cfs) Volume in (ft 3 ) Qout (cfs) Volumeout (ft 3 ) Volume detained (acre-feet) 5 9.95 84.822 25,446.53 1.90 570 0.571 10 7.72 65.811 39,486.87 1.90 1,140 0.880 15 6.52 55.582 50,023.53 1.90 1,711 1.109 20 5.60 47.739 57,286.66 1.90 2,281 1.263 25 4.98 42.454 63,680.26 1.90 2,851 1.396 30 4.52 38.532 69,357.77 1.90 3,421 1.514 35 4.08 34.781 73,040.49 1.90 3,992 1.585 40 3.74 31.883 76,518.60 1.90 4,562 1.652 45 3.46 29.496 79,638.68 1.90 5,132 1.710 50 3.23 27.535 82,605.31 1.90 5,702 1.765 55 3.03 25.830 85,239.48 1.90 6,273 1.813 60 2.86 24.381 87,771.34 1.90 6,843 1.858 65 2.70 23.017 89,766.14 1.90 7,413 1.891 70 2.60 22.164 93,090.82 1.90 7,983 1.954 75 2.50 21.312 95,904.00 1.90 8,554 2.005 80 2.40 20.460 98,205.70 1.90 9,124 2.045 85 2.30 19.607 99,995.90 1.90 9,694 2.073 90 2.20 18.755 101,274.62 1.90 10,264 2.089 100 2.05 17.476 104,855.04 1.90 11,405 2.145 110 1.90 16.197 106,900.99 1.90 12,545 2.166 120 1.75 14.918 107,412.48 1.90 13,686 2.152 130 1.60 13.640 106,389.50 1.90 14,826 2.102 140 1.40 11.935 100,251.65 1.90 15,967 1.935 150 1.20 10.230 92,067.84 1.90 17,107 1.721 160 1.15 9.804 94,113.79 1.90 18,248 1.742 170 1.10 9.377 95,648.26 1.90 19,388 1.751 180 1.05 8.951 96,671.23 1.90 20,529 1.748 Runoff Coefficient, C = 2-yr Release, Qout = Area = Appendix F H23 Final Drainage Report % Imperviousness 51.77% WQCV (inches)* =a(0.91i 3 -1.19i 2 +0.78i) 0.21 inches Volume = (WQCV/12)xA 0.20 ac-ft *WQCV in 40-hr drain time a=1.0 from Figure 3-2. Water Quality Capture Volume (WQCV) Based on BMP Drain Time UDFCD Storm Drainage Criteria Manual Volume 3 Table F-3 Water Quality Capture Volume (WQCV) Pond B Appendix F Project: Basin ID: Design Information (Input): Width of Basin Bottom, W = ft Right Triangle OR… Length of Basin Bottom, L = ft Isosceles Triangle OR… Dam Side-slope (H:V), Zd = ft/ft Rectangle OR… Circle / Ellipse OR… Irregular X (Use Overide values in cells G32:G52) MINOR MAJOR Storage Requirement from Sheet 'Modified FAA': acre-ft. Stage-Storage Relationship: Storage Requirement from Sheet 'Hydrograph': acre-ft. Storage Requirement from Sheet 'Full-Spectrum': acre-ft. Labels Water Side Basin Basin Surface Surface Volume Surface Volume Target Volumes for WQCV, Minor, Surface Slope Width at Length at Area at Area at Below Area at Below for WQCV, Minor, & Major Storage Elevation (H:V) Stage Stage Stage Stage Stage Stage Stage & Major Storage Stages ft ft/ft ft ft ft 2 ft 2 User ft 3 acres acre-ft Volumes (input) (input) Below El. (output) (output) (output) Overide (output) (output) (output) (for goal seek) 4839.25 (input) 0 0 0.000 0.000 4840.00 4.00 0.00 0.00 5,011 1,879 0.115 0.043 4841.00 4.00 0.00 0.00 17,323 13,046 0.398 0.299 4842.00 4.00 0.00 0.00 21,443 32,429 0.492 0.744 WQCV 4842.25 4.00 0.00 0.00 22,374 37,906 0.514 0.870 4843.00 4.00 0.00 0.00 25,317 55,790 0.581 1.281 4844.00 4.00 0.00 0.00 29,447 83,172 0.676 1.909 4845.00 4.00 0.00 0.00 33,669 114,730 0.773 2.634 100-yr + WQCV 4846.00 4.00 0.00 0.00 38,069 150,599 0.874 3.457 4847.00 4.00 0.00 0.00 42,725 190,996 0.981 4.385 4848.00 4.00 0.00 0.00 48,274 236,496 1.108 5.429 4849.00 4.00 0.00 0.00 60,555 290,910 1.390 6.678 #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A Project: Basin ID: STAGE-STORAGE SIZING FOR DETENTION BASINS 4839.00 4841.00 4843.00 4845.00 4847.00 4849.00 4851.00 0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 Stage (ft. elev.) Storage (acre-feet) STAGE-STORAGE CURVE FOR THE POND UD Detention Pond B VolCalc, Basin 2/24/2017, 1:55 PM Project: Basin ID: WQCV Design Volume (Input): Catchment Imperviousness, Ia = 51.8 percent Catchment Area, A = 11.52 acres Diameter of holes, D = 1.151 inches Depth at WQCV outlet above lowest perforation, H = 2 feet Number of holes per row, N = 1 Vertical distance between rows, h = 4.00 inches OR Number of rows, NL = 6.00 Orifice discharge coefficient, Co = 0.65 Height of slot, H = inches Slope of Basin Trickle Channel, S = 0.005 ft / ft Width of slot, W = inches Time to Drain the Pond = 24 hours Watershed Design Information (Input): 2 Percent Soil Type A = 20 % Percent Soil Type B = 49 % Percent Soil Type C/D = 31 % Outlet Design Information (Output): Water Quality Capture Volume, WQCV = 0.226 watershed inches Water Quality Capture Volume (WQCV) = 0.217 acre-feet 0.00 Design Volume (WQCV / 12 * Area * 1.2) Vol = 0.260 acre-feet Outlet area per row, Ao = 1.04 square inches Total opening area at each row based on user-input above, Ao = 1.04 square inches Total opening area at each row based on user-input above, Ao = 0.007 square feet 3 Row 1 Row 2 Row 3 Row 4 Row 5 Row 6 Row 7 Row 8 Row 9 Row 10 Row 11 Row 12 Row 13 Row 14 Row 15 Row 16 Row 17 Row 18 Row 19 Row 20 Row 21 Row 22 Row 23 Row 23  0.00 0.33 0.67 1.00 1.33 1.67 Flow 0.00 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.00 0.20 0.0169 0.0000 0.0000 0.0000 0.0000 0.0000 0.02 0.40 0.0238 0.0100 0.0000 0.0000 0.0000 0.0000 0.03 0.60 0.0292 0.0196 0.0000 0.0000 0.0000 0.0000 0.05 0.80 0.0337 0.0258 0.0136 0.0000 0.0000 0.0000 0.07 1.00 0.0377 0.0309 0.0217 0.0000 0.0000 0.0000 0.09 1.20 0.0413 0.0352 0.0274 0.0169 0.0000 0.0000 0.12 1.40 0.0446 0.0390 0.0322 0.0238 0.0100 0.0000 0.15 1.60 0.0477 0.0425 0.0364 0.0292 0.0196 0.0000 0.18 1.80 0.0506 0.0457 0.0401 0.0337 0.0258 0.0136 0.21 2.00 0.0533 0.0487 0.0435 0.0377 0.0309 0.0217 0.24 2.20 0.0559 0.0515 0.0466 0.0413 0.0352 0.0274 0.26 2.40 0.0584 0.0542 0.0496 0.0446 0.0390 0.0322 0.28 2.60 0.0608 0.0568 0.0524 0.0477 0.0425 0.0364 0.30 2.80 0.0631 0.0592 0.0550 0.0506 0.0457 0.0401 0.31 3.00 0.0653 0.0616 0.0575 0.0533 0.0487 0.0435 0.33 3.20 0.0674 0.0639 0.0600 0.0559 0.0515 0.0466 0.35 3.40 0.0695 0.0660 0.0623 0.0584 0.0542 0.0496 0.36 3.60 0.0715 0.0682 0.0645 0.0608 0.0568 0.0524 0.37 3.80 0.0735 0.0702 0.0667 0.0631 0.0592 0.0550 0.39 #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A Worksheet Protected Project: Basin ID: STAGE-DISCHARGE SIZING OF THE WATER QUALITY CAPTURE VOLUME (WQCV) OUTLET H23 Pond B 0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 4.00 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45 Stage (feet, elev.) Discharge (cfs) STAGE-DISCHARGE CURVE FOR THE WQCV OUTLET STRUCTURE UD Detention Pond B VolCalc, WQCV 2/24/2017, 2:08 PM Project: Basin ID: X 1 #1 Vertical #2 Vertical Sizing the Restrictor Plate for Circular Vertical Orifices or Pipes (Input) Orifice Orifice Water Surface Elevation at Design Depth Elev: WS = 4,846.00 feet Pipe/Vertical Orifice Entrance Invert Elevation Elev: Invert = 4,839.25 feet Required Peak Flow through Orifice at Design Depth Q = 1.90 cfs Pipe/Vertical Orifice Diameter (inches) Dia = 18.0 inches Orifice Coefficient Co = 0.65 Full-flow Capacity (Calculated) Full-flow area Af = 1.77 sq ft Half Central Angle in Radians Theta = 3.14 rad Full-flow capacity Qf = 22.6 cfs Percent of Design Flow = 1188% Calculation of Orifice Flow Condition Half Central Angle (0<Theta<3.1416) Theta = 0.75 rad Flow area Ao = 0.14 sq ft Top width of Orifice (inches) To = 12.27 inches Height from Invert of Orifice to Bottom of Plate (feet) Yo = 0.20 feet Elevation of Bottom of Plate Elev Plate Bottom Edge = 4,839.45 feet Resultant Peak Flow Through Orifice at Design Depth Qo = 1.9 cfs Width of Equivalent Rectangular Vertical Orifice Equivalent Width = 0.70 feet Centroid Elevation of Equivalent Rectangular Vertical Orifice Equiv. Centroid El. = 4,839.35 feet H23 Pond B RESTRICTOR PLATE SIZING FOR CIRCULAR VERTICAL ORIFICES UD Detention Pond B VolCalc, Restrictor Plate 2/24/2017, 2:09 PM H23 Final Drainage Report Detention Requirements Offsite Pond - Major Storm (100-yr) Mass Balance Method 0.85 0.94 cfs 5.69 acres Detention Requirements 1.25 acre-feet City of Fort Collins criteria (120%) 1.50 acre-feet Time (min) Intensity (in/hr) Qin (cfs) Volume in (ft 3 ) Qout (cfs) Volumeout (ft 3 ) Volume detained (acre-feet) 5 9.95 48.123 14,436.95 0.94 282 0.325 10 7.72 37.338 22,402.67 0.94 563 0.501 15 6.52 31.534 28,380.58 0.94 845 0.632 20 5.60 27.084 32,501.28 0.94 1,127 0.720 25 4.98 24.086 36,128.66 0.94 1,408 0.797 30 4.52 21.861 39,349.76 0.94 1,690 0.865 35 4.08 19.733 41,439.13 0.94 1,972 0.906 40 3.74 18.089 43,412.42 0.94 2,253 0.945 45 3.46 16.734 45,182.58 0.94 2,535 0.979 50 3.23 15.622 46,865.69 0.94 2,817 1.011 55 3.03 14.655 48,360.16 0.94 3,098 1.039 60 2.86 13.832 49,796.60 0.94 3,380 1.066 65 2.70 13.059 50,928.35 0.94 3,662 1.085 70 2.60 12.575 52,814.58 0.94 3,943 1.122 75 2.50 12.091 54,410.63 0.94 4,225 1.152 80 2.40 11.608 55,716.48 0.94 4,506 1.176 85 2.30 11.124 56,732.15 0.94 4,788 1.192 90 2.20 10.640 57,457.62 0.94 5,070 1.203 100 2.05 9.915 59,488.95 0.94 5,633 1.236 110 1.90 9.189 60,649.71 0.94 6,196 1.250 120 1.75 8.464 60,939.90 0.94 6,760 1.244 130 1.60 7.738 60,359.52 0.94 7,323 1.218 140 1.40 6.771 56,877.24 0.94 7,886 1.125 150 1.20 5.804 52,234.20 0.94 8,450 1.005 160 1.15 5.562 53,394.96 0.94 9,013 1.019 170 1.10 5.320 54,265.53 0.94 9,576 1.026 180 1.05 5.078 54,845.91 0.94 10,140 1.026 Runoff Coefficient, C = 2-yr Release, Qout = Area = Appendix F APPENDIX G FIRM Maps and Original Floodplain Workmap Page 1 of 5 Issue Date: August 1, 2014 Effective Date: December 15, 2014 Case No.: LOMR-APP 14-08-0580P Washington, D.C. 20472 Federal Emergency Management Agency LETTER OF MAP REVISION DETERMINATION DOCUMENT COMMUNITY AND REVISION INFORMATION PROJECT DESCRIPTION COMMUNITY APPROXIMATE LATITUDE & LONGITUDE: 40.518, -104.995 SOURCE: USGS QUADRANGLE DATUM: NAD 83 City of Fort Collins Larimer County Colorado COMMUNITY NO.: 080102 BASIS OF REQUEST IDENTIFIER NO PROJECT UPDATE Cache La Poudre River I-25 Divided Flow Path ANNOTATED MAPPING ENCLOSURES ANNOTATED STUDY ENCLOSURES TYPE: FIRM* NO.: 08069C0994F DATE: December 19, 2006 TYPE: FIRM* NO.: 08069C1013F DATE: December 19, 2006 DATE OF EFFECTIVE FLOOD INSURANCE STUDY: Enclosures reflect changes to flooding sources affected by this revision. * FIRM - Flood Insurance Rate Map; ** FBFM - Flood Boundary and Floodway Map; *** FHBM - Flood Hazard Boundary Map FLOODING SOURCE(S) & REVISED REACH(ES) Cache La Poudre River I-25 Divided Flow Path - from approximately 110 feet downstream of County Road 36 to approximately 140 feet upstream of County Road 38 SUMMARY OF REVISIONS Flooding Source Effective Flooding Revised Flooding Increases Decreases Cache La Poudre River I-25 Divided Flow Path Zone AE Zone AE YES YES Zone X (shaded) Zone X (shaded) YES YES Floodway Floodway YES YES * BFEs - Base Flood Elevations DETERMINATION This document provides the determination from the Department of Homeland Security's Federal Emergency Management Agency (FEMA) regarding a request for a Letter of Map Revision (LOMR) for the area described above. Using the information submitted, we have determined that a revision to the flood hazards depicted in the Flood Insurance Study (FIS) report and/or National Flood Insurance Program (NFIP) map is warranted. This document revises the effective NFIP map, as indicated in the attached documentation. Please use the enclosed annotated map panels revised by this LOMR for floodplain management purposes and for all flood insurance policies and renewals in your community. This determination is based on the flood data presently available. The enclosed documents provide additional information regarding this determination. If you have any questions about this document, please contact the FEMA Map Information eXchange toll free at 1-877-336-2627 (1-877-FEMA MAP) or by letter addressed to the LOMC Clearinghouse, 847 South Pickett Street, Alexandria, VA 22304-4605. Additional Information about the NFIP is available on our website at http://www.fema.gov/nfip. 132942 PT202.BKR.14080580P.H20 102-I-C Luis Rodriguez, P.E., Chief Engineering Management Branch Federal Insurance and Mitigation Administration FLOODWAY DATA TABLE: 4 February 06, 2013 Page 2 of 5 Issue Date: Effective Date: Case No.: 14-08-0580P LOMR-APP Washington, D.C. 20472 Issue Date: August 1, 2014 Effective Date: December 15, 2014 Federal Emergency Management Agency LETTER OF MAP REVISION DETERMINATION DOCUMENT (CONTINUED) OTHER COMMUNITIES AFFECTED BY THIS REVISION CID Number: 080101 Name: Larimer County, Colorado AFFECTED MAP PANELS AFFECTED PORTIONS OF THE FLOOD INSURANCE STUDY REPORT DATE OF EFFECTIVE FLOOD INSURANCE STUDY FLOODWAY DATA TABLE: 4 TYPE: FIRM* TYPE: FIRM* NO.: 08069C0994F NO.: 08069C1013F DATE: December 19, 2006 DATE: December 19, 2006 This determination is based on the flood data presently available. The enclosed documents provide additional information regarding this determination. If you have any questions about this document, please contact the FEMA Map Information eXchange toll free at 1-877-336-2627 (1-877-FEMA MAP) or by letter addressed to the LOMC Clearinghouse, 847 South Pickett Street, Alexandria, VA 22304-4605. Additional Information about the NFIP is available on our website at http://www.fema.gov/nfip. 132942 PT202.BKR.14080580P.H20 102-I-C Luis Rodriguez, P.E., Chief Engineering Management Branch Federal Insurance and Mitigation Administration : February 6, 2013 Page 3 of 5 Issue Date: Effective Date: Case No.: 14-08-0580P LOMR-APP Washington, D.C. 20472 Issue Date: August 1, 2014 Effective Date: December 15, 2014 Federal Emergency Management Agency LETTER OF MAP REVISION DETERMINATION DOCUMENT (CONTINUED) COMMUNITY INFORMATION APPLICABLE NFIP REGULATIONS/COMMUNITY OBLIGATION We have made this determination pursuant to Section 206 of the Flood Disaster Protection Act of 1973 (P.L. 93-234) and in accordance with the National Flood Insurance Act of 1968, as amended (Title XIII of the Housing and Urban Development Act of 1968, P.L. 90-448), 42 U.S.C. 4001-4128, and 44 CFR Part 65. Pursuant to Section 1361 of the National Flood Insurance Act of 1968, as amended, communities participating in the NFIP are required to adopt and enforce floodplain management regulations that meet or exceed NFIP criteria. These criteria, including adoption of the FIS report and FIRM, and the modifications made by this LOMR, are the minimum requirements for continued NFIP participation and do not supersede more stringent State/Commonwealth or local requirements to which the regulations apply. We provide the floodway designation to your community as a tool to regulate floodplain development. Therefore, the floodway revision we have described in this letter, while acceptable to us, must also be acceptable to your community and adopted by appropriate community action, as specified in Paragraph 60.3(d) of the NFIP regulations. COMMUNITY REMINDERS We based this determination on the base (1-percent-annual-chance) flood discharges computed in the FIS for your community without considering subsequent changes in watershed characteristics that could increase flood discharges. Future development of projects upstream could cause increased flood discharges, which could cause increased flood hazards. A comprehensive restudy of your community’s flood hazards would consider the cumulative effects of development on flood discharges subsequent to the publication of the FIS report for your community and could, therefore, establish greater flood hazards in this area. Your community must regulate all proposed floodplain development and ensure that permits required by Federal and/or State/Commonwealth law have been obtained. State/Commonwealth or community officials, based on knowledge of local conditions and in the interest of safety, may set higher standards for construction or may limit development in floodplain areas. If your State/Commonwealth or community has adopted more restrictive or comprehensive floodplain management criteria, those criteria take precedence over the minimum NFIP requirements. We will not print and distribute this LOMR to primary users, such as local insurance agents or mortgage lenders; instead, the community will serve as a repository for the new data. We encourage you to disseminate the information in this LOMR by preparing a news release for publication in your community's newspaper that describes the revision and explains how your community will provide the data and help interpret the NFIP maps. In that way, interested persons, such as property owners, insurance agents, and mortgage lenders, can benefit from the information. This determination is based on the flood data presently available. The enclosed documents provide additional information regarding this determination. If you have any questions about this document, please contact the FEMA Map Information eXchange toll free at 1-877-336-2627 (1-877-FEMA MAP) or by letter addressed to the LOMC Clearinghouse, 847 South Pickett Street, Alexandria, VA 22304-4605. Additional Information about the NFIP is available on our website at http://www.fema.gov/nfip. 132942 PT202.BKR.14080580P.H20 102-I-C Luis Rodriguez, P.E., Chief Engineering Management Branch Federal Insurance and Mitigation Administration Page 4 of 5 Issue Date: Effective Date: Case No.: 14-08-0580P LOMR-APP Washington, D.C. 20472 Issue Date: August 1, 2014 Effective Date: December 15, 2014 Federal Emergency Management Agency LETTER OF MAP REVISION DETERMINATION DOCUMENT (CONTINUED) COMMUNITY INFORMATION (CONTINUED) We have designated a Consultation Coordination Officer (CCO) to assist your community. The CCO will be the primary liaison between your community and FEMA. For information regarding your CCO, please contact: Ms. Jeanine D. Petterson Director, Mitigation Division Federal Emergency Management Agency, Region VIII Denver Federal Center, Building 710 P.O. Box 25267 Denver, CO 80225-0267 (303) 235-4830 STATUS OF THE COMMUNITY NFIP MAPS We will not physically revise and republish the FIRM and FIS report for your community to reflect the modifications made by this LOMR at this time. When changes to the previously cited FIRM panel(s) and FIS report warrant physical revision and republication in the future, we will incorporate the modifications made by this LOMR at that time. This determination is based on the flood data presently available. The enclosed documents provide additional information regarding this determination. If you have any questions about this document, please contact the FEMA Map Information eXchange toll free at 1-877-336-2627 (1-877-FEMA MAP) or by letter addressed to the LOMC Clearinghouse, 847 South Pickett Street, Alexandria, VA 22304-4605. Additional Information about the NFIP is available on our website at http://www.fema.gov/nfip. 132942 PT202.BKR.14080580P.H20 102-I-C Luis Rodriguez, P.E., Chief Engineering Management Branch Federal Insurance and Mitigation Administration Page 5 of 5 Issue Date: Effective Date: Case No.: 14-08-0580P LOMR-APP Washington, D.C. 20472 Issue Date: August 1, 2014 Effective Date: December 15, 2014 Federal Emergency Management Agency LETTER OF MAP REVISION DETERMINATION DOCUMENT (CONTINUED) COMMUNITY INFORMATION (CONTINUED) A notice of changes will be published in the Federal Register. This information also will be published in your local newspaper on or about the dates listed below and through FEMA’s Flood Hazard Mapping website at https://www.floodmaps.fema.gov/fhm/Scripts/bfe_main.asp. LOCAL NEWSPAPER Name: The Fort Collins Coloradoan Dates: August 8, 2014 and August 15, 2014 Within 90 days of the second publication in the local newspaper, a citizen may request that we reconsider this determination. Any request for reconsideration must be based on scientific or technical data. Therefore, this letter will be effective only after the 90-day appeal period has elapsed and we have resolved any appeals that we receive during this appeal period. Until this LOMR is effective, the revised flood hazard determination information presented in this LOMR may be changed. This determination is based on the flood data presently available. The enclosed documents provide additional information regarding this determination. If you have any questions about this document, please contact the FEMA Map Information eXchange toll free at 1-877-336-2627 (1-877-FEMA MAP) or by letter addressed to the LOMC Clearinghouse, 847 South Pickett Street, Alexandria, VA 22304-4605. Additional Information about the NFIP is available on our website at http://www.fema.gov/nfip. 132942 PT202.BKR.14080580P.H20 102-I-C Luis Rodriguez, P.E., Chief Engineering Management Branch Federal Insurance and Mitigation Administration 15,100 3,600 11,992 1.3 4,820.7 4,820.7 4,821.4 0.7 18,988 901 2,871 1.6 4,826.7 4,826.7 4,827.6 0.9 C 20,738 385 446 6.0 4,833.5 4,833.5 4,833.9 0.4 D 21,993 1,011 1,277 2.1 4,836.7 4,836.7 4,837.7 1.0 E 23,278 1,004 4,622 1.0 4,837.1 4,837.1 4,838.0 0.9 F 24,268 1,000 3,848 1.2 4,837.3 4,837.3 4,838.2 0.9 G 24,993 900 890 5.3 4,841.1 4,841.1 4,841.3 0.2 H 25,893 1,000 3,163 1.5 4,842.2 4,842.2 4,843.2 1.0 I 27,193 700 1,154 4.1 4,843.9 4,843.9 4,844.7 0.8 J 27,903 600 726 6.5 4,849.9 4,849.9 4,850.4 0.5 K 29,603 796 3,402 1.4 4,850.3 4,850.3 4,851.3 1.0 L 30,103 451 692 6.8 4,853.3 4,853.3 4,853.6 0.3 1 Feet above Larimer-Weld County Line Road FEDERAL EMERGENCY MANAGEMENT AGENCY LARIMER COUNTY, CO AND INCORPORATED AREAS CACHE LA POUDRE RIVER - I-25 DIVIDED FLOW TABLE 4 FLOODWAY 1-PERCENT ANNUAL CHANCE FLOOD WATER SURFACE ELEVATION FLOODWAY DATA CACHE LA POUDRE RIVER - INTERSTATE HIGHWAY 25 DIVIDED FLOW FLOODING SOURCE A B CROSS SECTION DISTANCE1 WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) REGULATORY (NAVD 88) INCREASE (FEET) WITHOUT FLOODWAY (FEET NAVD) WITH FLOODWAY (NAVD 88) REVISED DATA REVISED DATA 4834 4831 4832 FLOODING I-25 DIVIDED EFFECTS FLOW CHACHE LA POUDRE RIVER c7 STAR GAZER DRIVE ECLIPSE LANE OBSERVATORY DRIVE SOUTHERN CROSS LANE ROCK CREEK DRIVE STEELHEAD STREET PRECISION DRIVE , , , , K 4850.3 4850 4850 4847 4843 , , , , G 4841.1 , , , , H 4842.2 , , , , I 4843.9 BROOKFIELD DRIVE NORTHERN DRIVE LIGHTS CINQUEFOIL LANE 4837.1 , , , , C BIG DIPPER DRIVE LITTLE DRIVE DIPPER GALILEO DRIVE FULL DRIVE MOON , , , , J , , , , J 4849.9 , , , , L 4853.3 4835 4833 4836 4834 4834 4843 4828 4831 4836 4844 4831 4832 BYREVISED AREA LOMR DATED NOVEMBER 2008 14, 4853 4829 4830 4835 4837 4850 4837 4847 4837 4839 4841 4842 4843 4842 4841 4853 4850 REAVRIESAED 4836 4850 4837 4844 4839 , , , , I 4843.9 , , , , H APPENDIX H Excerpts from Referenced Reports Harmony & Strauss Cabin Convenience Shopping Center Subdivision Filing No. 1 PDP Final Drainage Report Page 12 sites). Release from these undeveloped areas amounts to 69.8 cfs. This amount will be treated as a pass-through flow. The resulting amount of stormwater passing from the detention basin will be approximately 78.8 cfs (9.0 + 69.8). Stormwater release from the detention basin will be provided at the existing spillway at the southeastern finger of Existing Gravel Pond #2. The required amount of stormwater detention for the combined CONVENIENCE SHOPPING CENTER and WEITZEL POND #1 project areas is 9.64 acre-feet based on the Modified FAA method for determining detention volumes, plus an additional 20% (City criteria), resulting in 11.57 acre-feet. The area of the Existing Gravel Ponds #1 and #2 will constitute the detention basin for this project. The storage capacity for that pond is provided below in Table 3. Table 3. Pond ID Surface Area Groundwater Surface Elevation Detention Surface Elevation Total Storage Ex. Gravel Pond #1 11.0 acres 4838.23 4838.59 3.96 Ac-ft Ex. Gravel Pond #2 14.53 acres 4837.12 4837.64 7.61 Ac-ft Total Required 11.57 Ac-ft The required detention water depth in the ponds is 0.36’ and 0.52’, respectively and will require that the existing spillway location top of bank to be raised to allow for detention capacity. In order to construct fill in the floodway a no-rise certification will be required to prove that the new elevations do not exceed those used in the approved LOMR 14-08-0580P (effective December 15, 2014). A spot elevation indicating 4835.5, located in the vicinity of the proposed improved spillway, is shown on that workmap. The elevations on that workmap are shown in NGVD29 datum, thus the translated elevations to the NAVD88 datum would be 3.18’ higher, resulting in a spot elevation of 4838.68 in this vicinity. This workmap is included in the Appendix for reference. In addition, the detention water surface elevation is still well below the Base Flood Elevations (BFE) as published on the current FEMA maps, the worst case BFE in that area being 4841. A WQCV calculation is provided, however, based on conversations with City stormwater staff, the existing gravel ponds can be used as water quality features for the stormwater releases from this site. In addition, the permeable pavement areas proposed for this project site are capable of storing approximately 0.41 ac-ft of WQCV within the sub-structure of those paved areas. Regardless, the calculated required WQCV for this site is 1.03 ac-ft, resulting in a total detention 11.57 Ac-ft 4837.12 4838.59 14.53 acres 4837.64 TAILWATER ELEVATION USED FOR STRAUSS CABIN ROAD STORM SEWER SIZING STORAGE REQUIREMENT FOR CONVENIENCE SHOPPING CENTER DESIGN ADDED TO STORAGE REQUIREMENT FOR "U" BASINS PER H23 DESIGN. Harmony and Strauss Cabin Subdivision Filing No. 1 Convenience Shopping Center PDP Drainage Report 2 - year 10 - year 100 - year 2 - year 10 - year 100 - year 2 - Year 10 - Year 100 - Year 2 - Year 10 - Year 100 - Year N-1 7.19 0.28 0.28 0.34 57 57 55 0.85 1.45 3.03 1.7 2.9 7.5 N-2 1.82 0.73 0.73 0.91 8 8 6 2.40 4.10 9.31 3.2 5.5 15.5 N-3 0.32 0.84 0.84 1.00 5 5 5 2.85 4.87 9.95 0.8 1.3 3.2 N-4 0.30 0.77 0.77 0.97 5 5 5 2.85 4.87 9.95 0.7 1.1 2.9 N-5 0.36 0.89 0.89 1.00 5 5 5 2.85 4.87 9.95 0.9 1.6 3.6 N-6 0.34 0.86 0.86 1.00 5 5 5 2.85 4.87 9.95 0.8 1.4 3.4 N-7 0.92 0.71 0.71 0.89 6 6 5 2.67 4.56 9.95 1.7 3.0 8.1 N-8 0.34 0.95 0.95 1.00 5 5 5 2.85 4.87 9.95 0.9 1.6 3.4 N-9 1.04 0.69 0.69 0.87 7 7 5 2.52 4.31 9.95 1.8 3.1 9.0 N-10 0.44 0.87 0.87 1.00 5 5 5 2.85 4.87 9.95 1.1 1.9 4.4 N-11 0.42 0.93 0.93 1.00 5 5 5 2.85 4.87 9.95 1.1 1.9 4.2 N-12 0.10 0.77 0.77 0.97 5 5 5 2.85 4.87 9.95 0.2 0.4 1.0 N-13 0.10 0.78 0.78 0.98 5 5 5 2.85 4.87 9.95 0.2 0.4 1.0 N-14 0.70 0.68 0.68 0.85 5 5 5 2.85 4.87 9.95 1.4 2.3 5.9 N-15 1.13 0.59 0.59 0.74 11 11 10 2.13 3.63 7.72 1.4 2.4 6.4 N-15 ULT 2.84 0.81 0.81 1.00 14 14 12 1.92 3.29 7.16 4.4 7.5 20.3 N-16 2.12 0.57 0.57 0.71 9 9 7 2.30 3.93 8.80 2.8 4.7 13.2 N-17 0.36 0.71 0.71 0.89 5 5 5 2.85 4.87 9.95 0.7 1.3 3.2 N-18 0.82 0.66 0.66 0.82 8 8 6 2.40 4.10 9.31 1.3 2.2 6.3 N-19 1.52 0.62 0.62 0.78 27 27 25 1.37 2.34 4.98 1.3 2.2 5.9 Total 28.5 48.7 128.5 PDP-N & S (EX CONDITION FOR N AND PROPOSED FILL CONDITION FOR S) 59.02 0.20 0.20 0.25 45 45 43 0.99 1.69 3.56 11.7 20.0 52.5 PDP-S 36.95 0.20 0.20 0.25 50 50 48 0.92 1.58 3.31 6.8 11.7 30.6 O-1 (EX. CONDITIONS OFFSITE) 27.2 0.20 0.20 0.25 69 69 68 0.82 1.40 2.86 4.5 7.6 19.4 O-2 (EX. CONDITIONS OFFSITE) 69.3 0.20 0.20 0.25 90 90 88 0.82 1.40 2.86 11.4 19.4 49.5 Pass-through Flow = 49.5+20.3=69.8 Time of Concentration, Tc (min) Table A-3 Basin Peak Discharge Basin Rainfall Intensity (in/hr) Peak Discharge (cfs) Basin Area (ac) Frequency Adj. Runoff Coefficients Appendix A O-1 (EX. CONDITIONS 27.2 0.20 0.20 0.25 69 69 68 0.82 1.40 2.86 4.5 7.6 19.4 OFFSITE) 2-yr Historic Release Rate (27.2 acres / 4.5 cfs = 0.165 cfs/ acre) 825' ROOKERY BUFFER (FOR REFERENCE ONLY) TAILWATER ELEVATION USED IN H23 DESIGN SPILLWAY TO BE MODIFIED WITH H23 DESIGN ALL RUNOFF FROM "U" BASINS WILL BE DETAINED IN EX. GRAVEL POND #2 H23 PROJECT SITE BASIN N-2 TO BE SUBDIVIDED WITH H23 DESIGN (BASIN CSC-1). THIS BASIN WILL NOW DRAIN TO TWO SEPARATE INLETS AS STRAUSS CABIN ROAD HAS BEEN REDESIGNED AND WILL NOW BE CONSTRUCTED WITH H23 IMPROVEMENTS. THESE INLETS HAVE BEEN DISCONNECTED WITH THE H23 DESIGN TO HELP ALLEVIATE PIPE CAPACITY AND SIZING CONSTRAINTS DOWNSTREAM THROUGH THE CONVENIENCE SHOPPING CETER SITE. INSTEAD RUNOFF FROM THE FRONTING HALF OF H23 WILL NOW BE ROUTED SOUTH VIA THE PROPOSED STORM SEWER SYSTEM WITHIN STRAUSS CABIN ROAD WHERE IT WILL ULTIMATELY DISCHARGE INTO THE EXISTING GRAVEL PONDS. APPENDIX I Proposed Drainage Maps 748 Whalers Way, Suite 200 Fort Collins, CO 80525 ideas@tstinc.com 970.226.0557 main 303.595.9103 metro 970.226.0204 fax www.tstinc.com 4842.2 , , , , F 4837.3 , , , , E 4837.1 , , , , D 4836.7 4833.5 , , , , C á á á á á á á á á á á á á á á á á á á á á á á á AB 4837.3 á á á á áá áá á á á á á á á á áá áá á á á á AC 4838.8 á á á á á á á á á á á á á á á á á á á á á á á á AD 4839.7 á á á á áá áá á á á á á á á á áá áá á á á á AE 4840.1 á á á á á á á á á á á á á á á á á á á á á á á á AF 4840.6 á á á á áá áá á á á á á á á á áá áá á á á á AG 4843.8 á á á á á á á á á á á á á á á á á á á á á á á á AH 4844.1 ZONE AE ZONE AE c36 k25 PONDS DRIVE COUNTY ROAD 36 ROAD Fort City Collins of 080102 Timnath Town of 080005 Town 080005 of Timnath Unincorporated Larimer County Areas 080101 FRONTAGE INTERSTATE ROAD 25 c 38 Cache I-La 25 Divided Poudre River Flow Path T. 7 N. T. 6 N. La Cache Poudre River BoxelderDitch Profile Baseline NOTE: IS LOCATED MAP AREA WITHIN SHOWN TOWNSHIP ON THIS 6 NORTH PANEL RANGE RANGE 68 68 WEST WEST. AND TOWNSHIP 7 NORTH 10 34 3 , , , , K 4850.3 BYREVISED LOMR AREA DATED JUNE 18, 2012 , , , , G 4841.1 Fossil Creek Reservoir Inlet HARMONY ROAD SCALE Map Projection: NAD83 STATE PLANE Colorado North FIPS 0501 (Feet) 1 inch = 500 feet 1:6,000 Western Hemisphere; Vertical Datum: NAVD88 0 250000 500 1,Feet 0 75 150 300 Meters NATIONAL FLOODPROGRAM INSURANCE FLOOD INSURANCE RATE MAP AndCOLORADO LARIMER Incorporated COUNTY, Areas PANEL 1013 OF 1420 Panel Contains: COMMUNITY NUMBER PANEL SUFFIX 1013 1013 1013 F F F FORT CITY OF COLLINS, LARIMER COUNTY TIMNATH, OF TOWN 080102 080101 080005 MAP NUMBER MAP REVISED 08069C1013F DECEMBER 19, 2006 VERSION N1U.MBER1.1.0 SPECIAL HAZARD FLOOD AREAS OTHER FLOOD AREAS HAZARD OF Without Base Flood Elevation (BFE) With BFE or Depth Regulatory Floodway 0.of 2% 1% Annual annual Chance chance Flood flood with Hazard, average Areas depth areas of less less than than one one foot square or with mile drainage Future Chance Conditions Flood Hazard 1% Annual Area SeeLevee Notes. with Reduced Flood Risk due to Zone A,V, A99 Zone AE, AO, AH, VE, AR Zone X Zone X Zone X 4849.9 4850 ZONE AE Fossil Creek Reservoir Inlet ZONE AE REAVRIESAED NOTE: IS LOCATED MAP AREA WITHIN SHOWN TOWNSHIP ON THIS 6 NORTH, PANEL RANGE RANGE 68 68 WEST WEST. AND TOWNSHIP 7 NORTH, City of 080102 Fort Collins Unincorporated Larimer County Areas 080101 9 10 33 34 3 4 c36 City of 080102 Fort Collins T. T. 7 6 N. N. H ARMONY ROAD SCALE Map Projection: NAD83 STATE PLANE Colorado North FIPS 0501 (Feet) 1 inch = 500 feet 1:6,000 Western Hemisphere; Vertical Datum: NAVD88 0 250000 500 1,Feet 0 75 150 300 Meters NATIONAL FLOODPROGRAM INSURANCE FLOOD INSURANCE RATE MAP AndCOLORADO LARIMER Incorporated COUNTY, Areas PANEL 994 OF 1420 Panel Contains: COMMUNITY NUMBER PANEL SUFFIX 0994 0994 F F FORT CITY OF COLLINS, LARIMER COUNTY 080102 080101 MAP NUMBER MAP REVISED 08069C0994F DECEMBER 19, 2006 VERSION N1U.MBER1.1.0 SPECIAL HAZARD FLOOD AREAS OTHER FLOOD AREAS HAZARD OF Without Base Flood Elevation (BFE) With BFE or Depth Regulatory Floodway 0.of 2% 1% Annual annual Chance chance Flood flood with Hazard, average Areas depth areas of less less than than one one foot square or with mile drainage Future Chance Conditions Flood Hazard 1% Annual Area SeeLevee Notes. with Reduced Flood Risk due to Zone A,V, A99 Zone AE, AO, AH, VE, AR Zone X Zone X Zone X #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A Override Area Row 1 Override Area Row 2 Override Area Row 3 Override Area Row 4 Override Area Row 5 Override Area Row 6 Override Area Row 7 Override Area Row 8 Override Area Row 9 Override Area Row 10 Override Area Row 11 Override Area Row 12 Override Area Row 13 Override Area Row 14 Override Area Row 15 Override Area Row 16 Override Area Row 17 Override Area Row 18 Override Area Row 19 Override Area Row 20 Override Area Row 21 Override Area Row 22 Override Area Row 23 Override Area Row 24 Central Elevations of Rows of Holes in feet Collection Capacity for Each Row of Holes in cfs STAGE-DISCHARGE SIZING OF THE WATER QUALITY CAPTURE VOLUME (WQCV) OUTLET H23 Pond B UD Detention Pond B VolCalc, WQCV 2/24/2017, 2:08 PM #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A STAGE-STORAGE SIZING FOR DETENTION BASINS H23 Check Basin Shape Pond B UD Detention Pond B VolCalc, Basin 2/24/2017, 1:55 PM #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A Override Area Row 1 Override Area Row 2 Override Area Row 3 Override Area Row 4 Override Area Row 5 Override Area Row 6 Override Area Row 7 Override Area Row 8 Override Area Row 9 Override Area Row 10 Override Area Row 11 Override Area Row 12 Override Area Row 13 Override Area Row 14 Override Area Row 15 Override Area Row 16 Override Area Row 17 Override Area Row 18 Override Area Row 19 Override Area Row 20 Override Area Row 21 Override Area Row 22 Override Area Row 23 Override Area Row 24 Central Elevations of Rows of Holes in feet Collection Capacity for Each Row of Holes in cfs STAGE-DISCHARGE SIZING OF THE WATER QUALITY CAPTURE VOLUME (WQCV) OUTLET H23 Pond A UD Detention Pond A VolCalc, WQCV 2/24/2017, 2:04 PM #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A STAGE-STORAGE SIZING FOR DETENTION BASINS H23 Check Basin Shape Pond A UD Detention Pond A VolCalc, Basin 2/24/2017, 1:43 PM 7B 4848.33 4848.70 0.00 0.00 4849.67 4849.70 4849.71 0.05 4849.76 DUMMY NODE INLET-7B 4848.70 4848.70 0.01 0.00 4849.72 4849.72 4849.77 0.00 4849.77 7C 4848.80 4849.14 0.00 0.00 4849.76 4849.76 4849.76 0.00 4849.76 DUMMY NODE INLET-7C 4849.14 4849.14 0.00 0.00 4849.76 4849.76 4849.76 0.00 4849.76 Loss Cross Section Rise (ft or in) Span (ft or in) 7A 246.12 4847.00 0.5 4848.23 0.013 0.03 0.00 CIRCULAR 24.00 in 24.00 in 7B 73.87 4848.33 0.5 4848.70 0.013 0.05 0.00 CIRCULAR 18.00 in 18.00 in DUMMY NODE INLET-7B 1.00 4848.70 0.5 4848.70 0.013 0.25 0.00 CIRCULAR 18.00 in 18.00 in 7C 67.36 4848.80 0.5 4849.14 0.013 1.32 0.00 CIRCULAR 18.00 in 18.00 in DUMMY NODE INLET-7C 1.00 4849.14 0.5 4849.14 0.013 0.25 0.00 CIRCULAR 18.00 in 18.00 in DUMMY NODE INLET-7A 1.00 4848.23 0.5 4848.23 0.013 0.25 0.00 CIRCULAR 24.00 in 24.00 in Sewer Flow Summary: Full Flow Capacity Critical Flow Normal Flow Element Name Flow (cfs) Velocity (fps) Depth (in) Velocity (fps) Depth (in) Velocity (fps) Froude Number Flow Condition Flow (cfs) Surcharged Length (ft) Comment 7A 16.04 5.11 12.65 5.20 12.62 5.21 1.00 Supercritical 8.73 0.00 7B 7.45 4.21 7.26 3.82 7.26 3.82 1.00 Subcritical 2.55 0.00 DUMMY NODE INLET-7B 7.45 4.21 6.83 3.69 6.82 3.70 1.00 Supercritical 2.27 0.00 DUMMY NODE INLET-6A 16.04 5.11 15.12 5.90 15.75 5.63 0.92 Pressurized 12.30 1.00  A Froude number of 0 indicates that pressured flow occurs (adverse slope or undersized pipe).  If the sewer is not pressurized, full flow represents the maximum gravity flow in the sewer.  If the sewer is pressurized, full flow represents the pressurized flow conditions. Sewer Sizing Summary: Existing Calculated Used Element Name Peak Flow (cfs) Cross Section Rise Span Rise Span Rise Span Area (ft^2) Comment 6A 12.30 CIRCULAR 24.00 in 24.00 in 24.00 in 24.00 in 24.00 in 24.00 in 3.14 DUMMY NODE INLET-6A 12.30 CIRCULAR 24.00 in 24.00 in 24.00 in 24.00 in 24.00 in 24.00 in 3.14  Calculated diameter was determined by sewer hydraulic capacity rounded up to the nearest commercially available size.  Sewer sizes should not decrease downstream.  All hydraulics where calculated using the 'Used' parameters. Coeff. Area Intensity (in/hr) Manhole Tc (min) Peak Flow (cfs) Comment FES-6A 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Surface Water Present (Upstream) 6A 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 12.30 Surface Water Present (Downstream) DUMMY NODE INLET- 6A 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 12.30 Loss (ft) Upstream (ft) 5A 4840.60 4841.29 0.00 0.00 4846.00 4846.21 4846.31 0.21 4846.53 5F 4843.86 4844.53 0.02 0.00 4846.53 4846.56 4846.55 0.03 4846.58 5G 4844.63 4845.00 0.01 0.00 4846.58 4846.59 4846.58 0.01 4846.59 (cfs) Velocity (fps) Depth (in) Velocity (fps) Depth (in) Velocity (fps) Froude Number Flow Condition Flow (cfs) Surcharged Length (ft) Comment 5A 101.84 8.10 27.15 7.72 25.55 8.32 1.12 Pressurized 56.56 137.52 5F 8.16 4.62 6.01 3.43 5.69 3.69 1.11 Pressurized 1.77 112.04 5G 7.45 4.21 4.22 2.83 4.20 2.84 1.01 Pressurized 0.89 74.32 DUMMY NODE INLET- 5E 7.45 4.21 4.22 2.83 4.20 2.84 1.01 Pressurized 0.89 1.00 DUMMY NODE INLET- 5D 8.16 4.62 4.22 2.83 4.01 3.03 1.10 Pressurized 0.89 1.00 5B 101.84 8.10 24.31 7.17 22.57 7.89 1.15 Pressurized 45.81 205.53 5C 101.84 8.10 24.31 7.17 22.57 7.89 1.15 Pressurized 45.81 106.50 5E 47.29 6.69 11.76 4.79 11.01 5.25 1.14 Pressurized 9.61 64.06 DUMMY NODE INLET- 5C 47.29 6.69 11.76 4.79 11.01 5.25 1.14 Supercritical 9.61 0.00 5D 47.29 6.69 23.91 7.53 24.22 7.42 0.98 Pressurized 37.53 103.17 DUMMY NODE INLET - 5B 47.29 6.69 23.91 7.53 24.22 7.42 0.98 Pressurized 37.53 1.00 5B 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 37.53 DUMMY NODE INLET- 5A 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 11.42 Sewer Input Summary: Elevation Loss Coefficients Given Dimensions Element Name Sewer Length (ft) Downstream Invert (ft) Slope (%) Upstream Invert (ft) Mannings n Bend Loss Lateral Loss Cross Section Rise (ft or in) Span (ft or in) 5A 137.52 4840.60 0.5 4841.29 0.013 0.00 0.00 CIRCULAR 48.00 in 48.00 in  A Froude number of 0 indicates that pressured flow occurs (adverse slope or undersized pipe).  If the sewer is not pressurized, full flow represents the maximum gravity flow in the sewer.  If the sewer is pressurized, full flow represents the pressurized flow conditions. Sewer Sizing Summary: Existing Calculated Used Element Name Peak Flow (cfs) Cross Section Rise Span Rise Span Rise Span Area (ft^2) Comment B1 14.17 CIRCULAR 24.00 in 24.00 in 24.00 in 24.00 in 24.00 in 24.00 in 3.14 DUMMY NODE 14.17 CIRCULAR 24.00 in 24.00 in 24.00 in 24.00 in 24.00 in 24.00 in 3.14  Calculated diameter was determined by sewer hydraulic capacity rounded up to the nearest commercially available size.  Sewer sizes should not decrease downstream.  All hydraulics where calculated using the 'Used' parameters. (in/hr) Manhole Tc (min) Peak Flow (cfs) Comment FES-3A 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 B1 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 14.17 DUMMY NODE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 14.17 DUMMY NODE INLET-2A 47.29 6.69 22.36 7.14 22.13 7.23 1.02 Pressurized 32.95 1.00  A Froude number of 0 indicates that pressured flow occurs (adverse slope or undersized pipe).  If the sewer is not pressurized, full flow represents the maximum gravity flow in the sewer.  If the sewer is pressurized, full flow represents the pressurized flow conditions. Sewer Sizing Summary: Existing Calculated Used Element Name Peak Flow (cfs) Cross Section Rise Span Rise Span Rise Span Area (ft^2) Comment 2A 32.95 CIRCULAR 36.00 in 36.00 in 33.00 in 33.00 in 36.00 in 36.00 in 7.07 DUMMY NODE INLET-2A 32.95 CIRCULAR 36.00 in 36.00 in 33.00 in 33.00 in 36.00 in 36.00 in 7.07  Calculated diameter was determined by sewer hydraulic capacity rounded up to the nearest commercially available size.  Sewer sizes should not decrease downstream.  All hydraulics where calculated using the 'Used' parameters. Coeff. Area Intensity (in/hr) Manhole Tc (min) Peak Flow (cfs) Comment FES-2A 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Surface Water Present (Upstream) 2A 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 32.95 Surface Water Present (Downstream) DUMMY NODE INLET- 2A 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 32.95 than the suggested height. Existing width is smaller than the suggested width. Exceeds max. Depth/Rise 1H 21.80 CIRCULAR 24.00 in 24.00 in 24.00 in 24.00 in 24.00 in 24.00 in 3.14 DUMMY NODE INLET 1A 21.80 CIRCULAR 30.00 in 30.00 in 24.00 in 24.00 in 30.00 in 30.00 in 4.91 1J 10.53 CIRCULAR 36.00 in 36.00 in 21.00 in 21.00 in 36.00 in 36.00 in 7.07 DUMMY NODE OUTLET STRUCTURE POND B 10.53 CIRCULAR 36.00 in 36.00 in 21.00 in 21.00 in 36.00 in 36.00 in 7.07  Calculated diameter was determined by sewer hydraulic capacity rounded up to the nearest commercially available size.  Sewer sizes should not decrease downstream.  All hydraulics where calculated using the 'Used' parameters. Grade Line Summary: Tailwater Elevation (ft): 4838.59 Invert Elev. Downstream Manhole Losses HGL EGL Element Name Downstream (ft) Upstream (ft) Bend Loss (ft) Lateral Loss (ft) Downstream (ft) Upstream (ft) Downstream (ft) Friction Loss (ft) Upstream (ft) 1A 4834.82 4835.11 0.00 0.00 4838.59 4838.67 4838.86 0.12 4838.98 1B 4835.21 4836.29 0.32 0.00 4839.00 4839.52 4839.30 0.63 4839.93 1C 4836.39 4837.58 0.01 0.18 4839.74 4840.51 4840.12 0.90 4841.02 1C 62.78 CIRCULAR 54.00 in 54.00 in 48.00 in 48.00 in 54.00 in 54.00 in 15.90 1I 18.90 CIRCULAR 24.00 in 24.00 in 24.00 in 24.00 in 24.00 in 24.00 in 3.14 DUMMY NODE INLET-1B 18.90 CIRCULAR 36.00 in 36.00 in 24.00 in 24.00 in 36.00 in 36.00 in 7.07 1D 30.29 CIRCULAR 48.00 in 48.00 in 33.00 in 33.00 in 48.00 in 48.00 in 12.57 1E 21.38 CIRCULAR 36.00 in 36.00 in 27.00 in 27.00 in 36.00 in 36.00 in 7.07 1F 2.70 CIRCULAR 18.00 in 18.00 in 12.00 in 12.00 in 18.00 in 18.00 in 1.77 in 18.00 in DUMMY NODE OUTLET A 1.00 4840.99 0.6 4841.00 0.013 0.25 0.00 CIRCULAR 18.00 in 18.00 in DUMMY NODE INLET- 1D 1.00 4840.59 0.5 4840.59 0.013 0.25 0.00 CIRCULAR 36.00 in 36.00 in 1G 78.58 4840.50 0.5 4840.89 0.013 1.32 0.00 CIRCULAR 18.00 in 18.00 in DUMMY NODE INLET- 1C 1.00 4840.89 0.5 4840.89 0.013 0.25 0.00 CIRCULAR 18.00 in 18.00 in 1H 14.00 4840.08 1.0 4840.22 0.013 1.32 0.00 CIRCULAR 24.00 in 24.00 in DUMMY NODE INLET 1A 1.00 4840.21 1.0 4840.22 0.013 0.25 0.00 CIRCULAR 30.00 in 30.00 in 1J 81.35 4836.84 0.5 4837.25 0.013 0.05 0.00 CIRCULAR 36.00 in 36.00 in DUMMY NODE OUTLET STRUCTURE POND B 1.00 4837.25 0.5 4837.25 0.013 0.25 0.00 CIRCULAR 36.00 in 36.00 in Sewer Flow Summary: Full Flow Capacity Critical Flow Normal Flow Element Name Flow (cfs) Velocity (fps) Depth (in) Velocity (fps) Depth (in) Velocity (fps) Froude Number Flow Condition Flow (cfs) Surcharged Length (ft) Comment 1A 116.79 5.95 27.54 7.54 32.37 6.14 0.73 Subcritical 66.29 0.00 1B 88.18 5.54 27.65 7.66 33.67 6.02 0.69 Subcritical 62.78 0.00 1C 88.18 5.54 27.65 7.66 33.67 6.02 0.69 Subcritical 62.78 0.00 DUMMY NODE INLET-1B 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 18.90 1D 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 30.29 1E 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 21.38 1F 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2.70 DUMMY NODE OUTLET A 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2.70 DUMMY NODE INLET-1D 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 18.70 1G 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 9.50 DUMMY NODE INLET-1C 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 9.50 1H 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 21.80 DUMMY NODE INLET 1A 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 21.80 1J 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 10.53 DUMMY NODE OUTLET STRUCTURE POND B 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 10.53 Table A-1a N-1 3.27 Onsite Basin Composite Runoff Coefficients Basin/ Sub- Basin Area (ac) Attribute 77.7% Attribute Area (ac) S-1 4.95 70.2% 0.74 Composite C Frequency Adjusted Runoff Coefficients (C*Cf) 0.74 0.74 0.92 0.80 Runoff Coefficient, C Percent Impervious 0.65 0.81 0.80 0.80 1.00 0.42 1.00 0.74 S-2 1.16 58.3% 0.65 0.65 U-1 2.09 76.3% 0.77 0.96 0.78 0.77 0.77 U-2 3.48 56.2% 0.63 0.63 0.63 S-6 0.35 N-5 1.54 44.0% 0.54 0.54 0.54 30.8% 0.44 0.44 0.44 0.54 0.68 0.24 0.30 55.9% 0.62 Appendix A From the City of Fort Collins Storm Drainage Design Criteria and Construction Standards Appendix A OLVWHGEHORZ 6RLO6XUYH\$UHD /DULPHU&RXQW\$UHD&RORUDGR 6XUYH\$UHD'DWD 9HUVLRQ6HS 6RLOPDSXQLWVDUHODEHOHG DVVSDFHDOORZV IRUPDSVFDOHV RUODUJHU 'DWH V DHULDOLPDJHVZHUHSKRWRJUDSKHG $SU²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ac-ft. This volume was then added to the 11.57 ac-ft required per the Convenience Shopping Center Report for a total volume of 13.07 ac-ft. Because Ex. Gravel Pond #1 has no available storage left, the 1.50 ac-ft was added to Ex. Gravel Pond #2. The approximate surface area of this pond was determined to be approximately 14.53 acres resulting in an increase of storage depth of 0.01 feet (1.50ac-ft / 14.53 acres). Because we will be adding additional storage volume in this pond, the emergency spillway designed with the Convenience