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HomeMy WebLinkAboutWINDSONG AT ROCK CREEK - FDP - FDP160010 - REPORTS - DRAINAGE REPORTFINAL DRAINAGE REPORT FOR WINDSONG AT ROCK CREEK Prepared For: VISTA POINTE DEVELOPMENT CO., LLC C/O Lenity Architecture 3150 Kettle Court SE Salem, Oregon 97301 April 20, 2016 Project No. 39727.00 Prepared By: JR Engineering, LLC 2900 South College Avenue, Suite 3D Fort Collins, CO 80525 Windsong at Rock Creek Final Drainage Report ii TABLE OF CONTENTS Engineer’s Certification Block ........................................................................................................... iii VICINITY MAP ................................................................................................................................... iv GENERAL DESCRIPTION AND LOCATION ............................................................................................ 1 LOCATION ..................................................................................................................................... 1 DESCRIPTION OF PROPERTY .......................................................................................................... 1 FLOODPLAIN SUBMITTAL REQUIREMENTS ..................................................................................... 2 DRAINAGE BASINS AND SUB-BASINS ................................................................................................. 3 MAJOR BASINS AND SUB-BASINS ................................................................................................... 3 SUB-BASIN DESCRIPTION ............................................................................................................... 4 EXISTING OFFSITE DRAINAGE BASINS ............................................................................................ 4 EXISTING ONSITE DRAINAGE BASINS ............................................................................................. 5 PROPOSED SUB-BASINS DESCRIPTIONS ......................................................................................... 6 DRAINAGE DESIGN CRITERIA ........................................................................................................... 16 REGULATIONS ............................................................................................................................. 16 MINIMIZATION OF THE DCIA ....................................................................................................... 16 DEVELOPMENT CRITERIA REFERENCE AND CONSTRAINTS ........................................................... 16 HYDROLOGIC CRITERIA ................................................................................................................ 16 HYDRAULIC CRITERIA ................................................................................................................... 17 FLOODPLAIN REGULATIONS COMPLIANCE ................................................................................... 17 MODIFICATIONS OF CRITERA ....................................................................................................... 17 DRAINAGE FACILITY DESIGN ............................................................................................................ 18 GENERAL CONCEPT ..................................................................................................................... 18 WATER QUALITY/ DETENTION FACILITIES .................................................................................... 18 LOW IMPACT DEVELOPMENT ...................................................................................................... 19 CONCLUSIONS ................................................................................................................................. 21 COMPLIANCE WITH STANDARDS ................................................................................................. 21 DRAINAGE CONCEPT ................................................................................................................... 21 REFERENCES .................................................................................................................................... 22 APPENDIX Appendix A – Figures Appendix B – Hydrologic Calculations Appendix C – Hydraulic Calculations Appendix D – Water Quality/Detention Calculations Appendix E – Maps Windsong at Rock Creek Final Drainage Report iii Engineer’s Certification Block I hereby certify that this Final Drainage Report for Windsong at Rock Creek was prepared by me (or under my direct supervision) for JR Engineering, LLC and the owners thereof and meets or exceeds the criteria of the City of Fort Collins Stormwater Design Standards. Timothy J. Halopoff, PE Registered Professional Engineer State of Colorado No. 37953 Windsong at Rock Creek Final Drainage Report iv VICINITY MAP Windsong at Rock Creek Final Drainage Report 1 GENERAL DESCRIPTION AND LOCATION LOCATION Windsong at Rock Creek is located in the southeast quarter of Section 4, Township 6 North, Range 68 West of the 6th Principal Meridian in the City of Fort Collins, Larimer County, Colorado. More specifically, the Windsong site is a 3.334 acre property that is currently undeveloped and is being used for agricultural purposes. The site is zoned HC, Harmony Corridor, and will support a memory care facility and associated amenities once developed. The Windsong at Rock Creek site is bounded on the south by Rock Creek Drive, on the west by Ziegler Road, and on the north and east by unplatted land. Further to the east of the site lies Technology Parkway, and further to the north of the site lies existing right-of-way for Precision Drive, although the roadway has not been constructed between Technology Parkway and Ziegler Road. Surrounding developments include Harvest Park west of Ziegler Road, Fossil Ridge High School south of Rock Creek Drive, Harmony Technology Park Filing 3 east of Technology Parkway and Brookfield/Morningside to the east of Filing 3, and Harmony Technology Park Filing 1 north of Precision Drive. The site is only encumbered by a 15-foot utility easement on the west side, paralleling Ziegler Road. The site is located in the McClellands drainage basin and there are no major drainageways adjacent to the site. DESCRIPTION OF PROPERTY The Windsong at Rock Creek site is 3.334 acres at the northeast corner of Ziegler Road and Rock Creek Drive. The existing site generally slopes from the southwest to the northeast with slopes ranging between 0.70% and 3.5%. The property is generally covered with sparse native grasses. The site currently drains to the east. Runoff sheet flows off the east side of the property and a portion of the runoff flows to the west after the berm along the far west of the property. The Windsong site’s soils consist of loamy soil, predominately Nunn clay loam. Nunn clay loam belongs to hydrologic soils Group C. Group C soils have a slow infiltration rate when thoroughly wet. These consist chiefly of soils having a layer that impedes the downward movement of water or soils of Windsong at Rock Creek Final Drainage Report 2 moderately fine texture or fine texture. These soils have a slow rate of water transmission. The slopes of the Nunn clay loam ranges from 0-3 percent. Supporting figures can be found in the Appendix, page A-1. An existing irrigation ditch is located on the west end of the site paralleling Ziegler Road. According to the Main Street Health & Wellness Suites final plat by Edmonds Land Surveying, Inc., recorded May 22, 2015, this irrigation easement has been granted to the Poudre School District. This private irrigation ditch, per the approved Main Street Health & Wellness Suites Final Drainage and Erosion Control Report by Aspen Engineering, dated February 18, 2015, is being abandoned in place through the entire Harmony Technology Park. As such, the irrigation ditch will be abandoned in place with the proposed Windsong at Rock Creek Development. The proposed use of the site is a memory care assisted living facility. The proposed concept includes one main building with two patios, two internal courtyards, garden plaza with walkways, and parking lots within the perimeter of the site. The proposed main building is 38,131 total square feet. FLOODPLAIN SUBMITTAL REQUIREMENTS The site is shown on FEMA FIRM panel 08069C0994F, dated December 19, 2006. The site lies within Zone X, areas which are determined to be outside the 0.2% annual chance floodplain. The “City of Fort Collins Floodplain Review Checklist for 50% Submittals” checklist is not applicable for this PDP Drainage Report. The FIRM panel is included in Appendix A. Windsong at Rock Creek Final Drainage Report 3 DRAINAGE BASINS AND SUB-BASINS MAJOR BASINS AND SUB-BASINS The proposed Windsong Fort Collins site is located in the McClellands major basin. The McClellands Basin encompasses approximately 3.4 square miles in southeast Fort Collins. The storm runoff from the basin originates northeast of College Avenue and Harmony Road and drains southeast through the Oakridge, Willow Springs, Stetson Creek and Harvest Park developments. A single major drainageway, McClellands Creek, conveys flow from the upper end of the basin to the downstream discharge point along the Fossil Creek Reservoir Inlet Ditch. The majority of the basin is either developed, or is being developed, with residential and commercial land areas. There are no major drainageways located within or immediately adjacent to the site. The McClellands Basin was developed in accordance with its original master plan and storm drainage criteria; therefore, many of the recommended improvements were completed. However, there are still some localized flooding problems. The recommended plan of improvements includes pond enlargement, spillway construction, and inlet additions. Once these improvements are completed, the existing facilities would be up to current drainage standards. The “McClellands Creek Basin Selected Plan – Water Quality Improvements Drainage Master Plan Update”, prepared by ICON Engineering, Inc., shows the proposed water quality improvements which includes retrofitting the existing Miramont, Oak Ridge, Willow Springs, Preston Jr. High, and the Harmony Crossing Ponds to accommodate the required water quality volumes. As well, stream restoration and habitat improvements are proposed along the McClellands Creek. The Drainage Master Plan update is currently underway and is to portray these proposed improvements to the McClellands Basin. The site is located at the east part of the basin outside the McClelland’s Creek Floodplain shown in the “McClelland’s Creek Master Drainage Plan Update” by Icon Engineering. The site is located south of an area with existing flood control and east of an area with both existing water quality and flood control. The site itself is located in an area with neither flood control or water quality. Improvements identified in the previous approved Drainage Reports include the design of five detention ponds within the Oak/Cottonwood Farm development prepared by RBD, Inc. Engineering Consultants in May 1992 and revised in March 1995 [2]. The construction of Lot 1, Lot 2, Boardwalk Crossing, Filing 2 located north of West Harmony Road and west of South College Avenue has been designed to have the runoff be routed to the system in Boardwalk Drive and was designed in 1996 by Stewart & Associated, Inc. [3]. Windsong at Rock Creek Final Drainage Report 4 Regional Detention Pond 278 and 247 located west of Pleasant Valley Lake and east of Seneca Street were designed by Sear-Brown Group in October 2000 [4]. Six detention ponds were designed for the development north of Ketcher road and west of Strauss Cabin Road by Northern Engineering in December 2010 [5]. SUB-BASIN DESCRIPTION Windsong is governed by the City’s Reasonable Use policy, in which the proposed drainage basins will need to follow the generally accepted principle of releasing the 100-year developed condition flow rate at the same location and magnitude as the 2-year pre-development condition flow rate. There are offsite areas that flow across the proposed development site. The existing drainage basins within the site flow to the either East of the site or North of the site. Referring to the “Existing Drainage Plan”, included in the Appendix, the following describes the existing condition drainage basins. EXISTING OFFSITE DRAINAGE BASINS The site has one existing offsite drainage sub-basin that flow onto the site. The existing offsite land use is classified as farming/agricultural, but for the analysis, the land use will be assumed to have a 45% imperviousness (for undefined land use) to be provide a conservative approximation of the offsite flows entering the Windsong site. The conservative imperviousness will account for any changes or fluctuations of the surface characteristics north of the site. In the ultimate condition, the offsite flows will be collected and conveyed to a separate storm system within the respective developments and these developed flows will no longer enter the Windsong site. SUB-BASIN (OF1) Sub-basin OF1 consists of 2.30 acres north of the site and is assumed to drain in a southeasterly direction onto the subject property. Based on the surveyed surface characteristics north of the site and the Google topography, the slopes are assumed to match the surveyed area north of site and will continue to drain in the southeast direction. In the existing condition, runoff from this portion of the farm field (assumed 2% impervious) is conveyed through the Windsong site. In the future, the land north of the site is planned to be developed and the offsite runoff will be directed away from the Windsong property. It is assumed that the slopes are consistent with the slopes just north of the site, with a range from 0.5% to 1.0%. Windsong at Rock Creek Final Drainage Report 5 EXISTING ONSITE DRAINAGE BASINS The site has three existing onsite drainage basins approximately delineated by a high point at the middle and southern end of the site with sub-basin EX1 on the north half and EX2 on the southern half. Sub- basin EX2 and sub-basin EX3 border the roadway. Sub-basin EX2 drains to the south and then east along the curb. Sub-basin EX3 runoff drains to the west and then north along the curb. SUB-BASIN (EX1) Sub-basin EX1 consists of a 2.99 acre area of undeveloped farm land with native grasses covering the majority of the ground and is assumed to be 2% impervious for historic flow analysis. Runoff from the north farm land (Sub-basins OF1 and OF2) enters the site along the northern boundary and joins on-site flows. Runoff generally flows southeasterly across basin EX-1, at slopes ranging from 0.50% to 1.0%. There is an existing low point east of the site that causes the onsite and offsite runoffs to converge in northern half of the basin and then drain east off the site. The offsite runoff flows southeast, converges in the northern half, and then flows east off the site. The sub-basin onsite runoff from the south flows northeast towards the same low point outside the site. Towards the southern end of the sub-basin, there is a ridge that directs runoff on the southern end of the ridge to drain south towards the roadway. An existing berm along the northern section of the roadway redirects a portion of the runoff back east off the site. All flows within the sub-basin EX1 exit the site at the east boundary. SUB-BASIN (EX2) Sub-basin EX2 consists of a 0.17 acre area of undeveloped farm land with native grasses covering the majority of the ground and is assumed to be 2% impervious for historic flow analysis. Sub- basin EX2 borders the north side of the existing Rock Creek Drive roadway. Runoff that that drains south of the ridge on the southern side of the site flows over the existing berm and into the roadway curb. The curb then directs the flows to the east. Runoff north of the berm generally flows southeasterly towards the roadway, at slopes ranging from 0.50% to 0.8%. Across the berm the slopes range from 6.0%-10.0% and along the curb the slope is ranges from 0.40% to 1.30%. Windsong at Rock Creek Final Drainage Report 6 SUB-BASIN (EX3) Sub-basin EX7 consists of a 0.19 acre area of undeveloped farm land with native grasses covering the majority of the ground and is assumed to be 2% impervious for historic flow analysis. Sub- basin EX7 borders the east side of the existing Ziegler Road roadway and west of the existing concrete channel. The runoff drains west of the existing concrete channel and east of the roadway curb. The stormwater converges to the bottom of the slope that lies in between the curb and channel before being routed north of the site. The slope ranges from 0.05% to 7.0%. Along the southwest side of the site and within the sub-basin, the runoff flows west towards the existing Zeigler Drive roadway and then the curb directs the flows east. The slopes range from 2.5% to 3.0%. All flows within the sub-basin EX2 exit the site at the south end and flow east along the existing roadway curb. PROPOSED SUB-BASINS DESCRIPTIONS No offsite flows will enter the site once it is developed, as concurrent development is expected to take place for the filing north of the Windsong site. Offsite flows will be accounted for with onsite water quality and detention in their respective filings. SUB-BASIN A1 Sub-basin A1consists of 0.39 acres and is located at the northwest corner of the subject property. Sheet flow from the northwest side of the proposed building and parking lot will travel north to a parking lot curb. Once the runoff drains into the proposed inlet, it will route the runoff to the stormwater system on the east side of the site. The flow will be piped and then routed east and then south through the storm sewer to the sand filter Pond C and then outfall into Detention Pond A. The east side of the berm along the northwest corner of the site will direct the sheet flows to collect on the parking lot and sheet flow towards the low point in the curb. The slope of the initial flow across the parking lot is ranges from 2.0 % to 2.10%. The longitudinal slope of the sidewalks ranges from 0.5% to 4.5%. The imperviousness of the asphalt is set at 100% and the imperviousness of the concrete curb and sidewalks/walkways is set at 90%. The imperviousness of the roof of the building will be set at 90%. All areas outside the parking lot, building and sidewalks are assumed to be lawn with an imperviousness set at 5%. Windsong at Rock Creek Final Drainage Report 7 SUB-BASIN A2 Sub-basin A2 consists of 0.50 acres and is located at the northeast corner of the subject property, adjacent to sub-basin A1. Sheet flow from the north-center and northeast side of the proposed building and parking lot travels north to a parking lot curb and into the area inlet. Once the runoff drains into the area inlet, the stormwater will be routed to the stormwater system on the east side of the site. The flow will be piped through the storm sewer system to the sand filter pond C and then outfall into Detention Pond A. The slope of the initial flow across the parking lot is ranges from 1.90 % to 3.0. The longitudinal slope of the sidewalks ranges from 0.5% to 7.5%. The imperviousness of the asphalt is set at 100% and the imperviousness of the concrete curb and sidewalks/walkways is set at 90%. The imperviousness of the roof of the building will be set at 90%. All areas outside the parking lot, building and sidewalks are assumed to be lawn with an imperviousness set at 5%. SUB-BASIN A3 Sub-basin A3 consists of 0.11 acres and is located on the east side of the subject property. Runoff from this basin drains to the proposed sump inlet at DP3. Captured flows are piped to the sand filter in basin A8 before being routed south to Detention Pond A before exiting the site. The slope towards the sump inlet ranges from 5.0 % to 25.0%. All areas outside the parking lot, building and sidewalks are assumed to be lawn with an imperviousness set at 5%. SUB-BASIN A4 Sub-basin A4 consists of 0.18 acres and is located on the west side of the building within the subject property. The basin consists of the building patio and the swale directing flow to the north. Runoff from the west side of the building will flow from the roof and into the concrete patio or area inlets north of the patio. In the patio area, the runoff will enter the area inlets with the piped flows routed east. The swale west of the patio berm collects the runoff from the berms on the east and west side of the swale and directs the flows north to the area inlet Windsong at Rock Creek Final Drainage Report 8 outside of the patio. The piped flows will then travel south and combine with the piped flows from within the patio. The piped flows travel west and connect to the proposed storm sewer system on the west side of the building patio with a tee fitting. The storm sewer system directs the runoff south to the sand filter Detention Pond B before outfall into Detention Pond A. The slope of the initial flow across the concrete courtyard lot ranges from 1.00 % to 2.0%. The imperviousness of the concrete is set at 90%. The imperviousness of the roof of the building will be set at 90%. All areas outside the parking lot, building and sidewalks are assumed to be lawn with an imperviousness set at 5%. SUB-BASIN A5 Sub-basin A5 consists of 0.24 acres and encompasses the west-half of the building within the subject property. Runoff from the west half of the building will flow from the roof and into the concrete courtyard. The runoff will enter two proposed area inlets with the piped flows routed west. The runoff in sub-basin A5 combines with the piped flows from sub-basin A4. The piped flows travel west and connect to the proposed storm sewer system on the west side of the building patio with a tee fitting. The storm sewer system directs the runoff south to the sand filter Detention Pond B before outfalling into Detention Pond A. The slope of the initial flow across the concrete courtyard lot ranges from 1.00 % to 2.0%. The imperviousness of the concrete is set at 90%. The imperviousness of the roof of the building will be set at 90%. SUB-BASIN A6 Sub-basin A6 consists of 0.24 acres and encompasses the east-half of the building within the subject property. Runoff from the east half of the building will flow from the roof and into the concrete courtyard. The runoff will enter two proposed area inlets with the piped flows routed east. The piped flows travel east and connect to the proposed storm sewer system on the east side of the building patio (sub-basin A8) and into the proposed sand filter Pond C. Pond C outfalls south to Detention Pond A before exiting the site. Windsong at Rock Creek Final Drainage Report 9 The slope of the initial flow across the concrete courtyard lot ranges from 1.00 % to 2.0%. The imperviousness of the concrete is set at 90%. The imperviousness of the roof of the building will be set at 90%. SUB-BASIN A7 Sub-basin A7 consists of 0.10 acres and is located on the east side of the building within the subject property. The basin consists of only the building patio. Runoff from the east side of the building will flow from the roof into the concrete patio and enter the proposed area inlets with the piped flows routed east. The runoff in sub-basin A7 combines with the piped flows from sub-basin A6. The piped flows travel east and connect to the proposed storm sewer system on the east side of the building patio (sub-basin A8) and into the proposed sand filter Pond C. Pond C outfalls south to Detention Pond A before exiting the site. The slope of the initial flow across the concrete courtyard lot ranges from 1.00 % to 2.0%. The imperviousness of the concrete is set at 90%. The imperviousness of the roof of the building will be set at 90%. All areas outside the parking lot, building and sidewalks are assumed to be lawn with an imperviousness set at 5%. SUB-BASIN A8 Sub-basin A8 consists of 0.19 acres and is located on the east side of the building and patio within the subject property and includes the sand filter Pond C. The ridge along the east side of the sub-basin is set higher than the sidewalk, directing the runoff on the east side of the ridge to flow to the private roadway. The runoff within the sub-basin flows into the sand filter which provides water quality. One the water quality level is exceeded flows are piped south to Detention Pond A prior to exiting the site. The slope of the initial flow across the lawns range from 2.0 % to 25% and across the patio the slope is ranges from 1.0% to 2.0%. All areas outside the building and patio are assumed to be lawn with an imperviousness set at 5%. Windsong at Rock Creek Final Drainage Report 10 SUB-BASIN A9 Sub-basin A9 consists of 0.09 acres and is located on the south side of the building within the subject property. The sub-basin includes a proposed area inlet and swale. Runoff from the building sheet falls into the swale and is routed west towards the proposed area inlet. The piped flows are routed east to the proposed sand filter Pond C prior to outfalling into Detention Pond A. The slopes towards the area inlet range from 8.0 % to 20.0% with the swale slope at a 2.0%. All areas outside the parking lot, building and sidewalks are assumed to be lawn with an imperviousness set at 5%. SUB-BASIN A10 Sub-basin A10 consists of 0.02 acres and is located in the middle of the south parking lot within the subject property. Runoff from the sidewalk to the west of the basin sheet falls to the proposed area inlet at the center of the sub-basin. The piped flows are routed east through the sub-basin A11 proposed inlet prior to outfalling into Detention Pond A. The slopes towards the area inlet range from 2.0 % to 15.0%. The imperviousness of the concrete patio is set at 90% and all areas outside the parking lot, building and sidewalks are assumed to be lawn with an imperviousness set at 5%. SUB-BASIN A11 Sub-basin A11consists of 0.12 acres and is located north of the south property entrance of the subject property. A ridge will stretch from the west side of the property entrance and north to the sub-basin B5 curb, causing the parking lot to be broken up into two sub-basins. The two sub-basins will be located on the east and west side of the parking lot, with sub-basin A11 on the east side. The runoff from the property entrance travels northeast and the runoff on the east side of the building entrance travels southeast to the inlet prior to outfalling into Detention Pond A. The piped flows at the inlet will combine with runoff from Pond B, as well as runoff from Basins A10, B4 and B5. Windsong at Rock Creek Final Drainage Report 11 The slope of the initial flow across the parking lot is ranges from 0.05 % to 2.8% and the slope across the sidewalks/pathways ranges from 1.0% to 4.0%. The imperviousness of the asphalt is set at 100% and the imperviousness of the concrete curb and sidewalks/walkways is set at 90%. The imperviousness of the roof of the building will be set at 90%. SUB-BASIN A12 Sub-basin A12 consists of 0.29 acres and is located at the southeast corner of the property and includes Detention Pond A. The pond will collect runoff from sub-basins A1 to A11 and B1 to B5 prior to exiting the site. In a major storm situation, the stormwater in the pond can back up into Pond B, which is tributary to Detention Pond A. The sub-basin itself includes the pond and the parking lot to the north of the pond. A proposed inlet will be placed at the low point in the curb, causing the runoff in the parking lot to sheet flow and drain into the pond. At the east side of the pond, an outlet structure with a restrictor plate is proposed to outfall the stormwater to the existing storm sewer system to the east of the site. The slope of the sheet flow across the parking lot ranges from 0.75 % to 2.0% and the slope across the bottom of the pond is approximately 2.0%. The imperviousness of the asphalt is set at 100% and the imperviousness of the concrete curb and sidewalks/walkways is set at 90%. The imperviousness of the roof of the building will be set at 90% and all areas outside the parking lot, building and sidewalks are assumed to be lawn with an imperviousness set at 5%. SUB-BASIN B1 Sub-basin B1 consists of 0.04 acres and is located at the southwest side of the building patio within the subject property. The sub-basin consists of a proposed area inlet and swale. Runoff from the berm along the patio and the berm on the east side of the sidewalk collects into the swale and is routed to the proposed area inlet. The collected flows are piped south into the proposed sand filter Detention Pond B where the runoff is then routed to the Detention Pond A. The slope of the swale is approximately 2.0% and the slope from the building and berms ranges from 10.0 % to 20.0%. All areas outside the parking lot, building and sidewalks are assumed to be lawn with an imperviousness set at 5%. Windsong at Rock Creek Final Drainage Report 12 SUB-BASIN B2 Sub-basin B2 consists of 0.21 acres and is located at the southwest corner of the property and includes the sand filter Detention Pond B. The pond is tributary to Detention Pond A and will outfall into Pond A prior to exiting the site. In a major storm situation, the stormwater in the Pond A can back up into Pond B and allows the ponds to be considered one detention pond. The sub-basin itself includes the pond and the land on the north and east side of the berms. The runoff within the basin will outfall into the Pond B and will combine with runoff from Basins A4, A5, B1 and B3 piped flows. The side slope of the pond is approximately 25%. The imperviousness of the concrete sidewalks/walkways is set at 90% and all areas outside the parking lot, building and sidewalks are assumed to be lawn with an imperviousness set at 5%. SUB-BASIN B3 Sub-basin B3 consists of 0.08 acres and is located on the south side of the building within the subject property. The sub-basin includes a proposed area inlet and swale. Runoff from the building sheet falls into the swale and is routed towards the proposed area inlet. The piped flows are routed south to the proposed sand filter Detention Pond B prior to outfalling into Detention Pond A. The slope towards the area inlet ranges from 4.0 % to 10.0% with the swale slope ranges from 2.0% to 3.0%. All areas outside the parking lot, building and sidewalks are assumed to be lawn with an imperviousness set at 5%. SUB-BASIN B4 Sub-basin B4 consists of 0.14 acres and is located north of the south property entrance of the subject property. A ridge will stretch from the west side of the property entrance and north to the sub-basin B5 curb, causing the parking lot to be broken up into two sub-basins. The two sub-basins will be located on the east and west side of the parking lot, with sub-basin B4 on the Windsong at Rock Creek Final Drainage Report 13 west side. The runoff from the property entrance travels northwest and the runoff on the west side of the building entrance travels southwest to the inlet prior to outfalling into Detention Pond A. The piped flows at the inlet will combine with runoff from Detention Pond P. The Detention Pond B east ridge is set higher than the sidewalk, directing the runoff on the east side of the ridge to flow to the parking lot. The slope of the initial flow across the parking lot is ranges from 2.0 % to 3.0% and the slope across the sidewalks/pathways ranges from 0.5% to 4.0%. The imperviousness of the asphalt is set at 100% and the imperviousness of the concrete curb and sidewalks/walkways is set at 90%. The imperviousness of the roof of the building will be set at 90%. SUB-BASIN B5 Sub-basin B5 consists of 0.02 acres and is located in the middle of the south parking lot within the subject property. The lawn within the basin sheet flows to the proposed area inlet at the center. The piped flows are routed east through the sub-basin A11 proposed inlet prior to outfalling into Detention Pond A. The slope towards the area inlet ranges from 1.0 % to 10.0%. All areas outside the parking lot, building and sidewalks are assumed to be lawn with an imperviousness set at 5%. SUB-BASIN C1 Sub-basin C1 consists of 0.06 acres and is located on the west side of the subject property. The flows are routed offsite and will flow down to the existing curb along Ziegler Road. The existing curb will then direct the runoff north of the site. The slope of the flow from the sidewalk is approximately 2.0% and the slope down from the proposed berms is approximately 25%. The imperviousness of the concrete sidewalks/walkways is set at 90% and all areas outside the parking lot, building and sidewalks are assumed to be lawn with an imperviousness set at 5%. Windsong at Rock Creek Final Drainage Report 14 SUB-BASIN C2 Sub-basin C2 consists of 0.13 acres and is located on the west side of the subject property. The flows are routed offsite and will flow down to the existing curb along Ziegler Road. The existing curb will then direct the runoff south of the site. The slope of the flow from the sidewalk is approximately 2.0% and the slope down from the proposed berms is approximately 25%. The runoff at the south entrance flows to the existing curb and is directed east. The imperviousness of the concrete sidewalks/walkways is set at 90% and all areas outside the parking lot, building and sidewalks are assumed to be lawn with an imperviousness set at 5%. SUB-BASIN C3 Sub-basin C3 consists of 0.10 acres and is located on the south side of the subject property. The flows are directed offsite and will flow down to the existing curb along Rock Creek Drive roadway. The existing curb will then direct the runoff east of the site. The slope of the flow from the sidewalk ranges from 2.0% to 8.50% and the slope down from the proposed berms is approximately 25%. The runoff at the south entrance flows to the existing curb and is directed east. The imperviousness of the concrete curb and sidewalks/walkways is set at 90% and all areas outside the parking lot, building and sidewalks are assumed to be lawn with an imperviousness set at 5%. SUB-BASIN C4 Sub-basin C4 consists of 0.09 acres and is located on the south side of the subject property. The flows are directed offsite and will flow down to the existing curb along Rock Creek Drive roadway. The existing curb will then direct the runoff east of the site. The slope of the flow from the sidewalk is approximately 2.0%. The imperviousness of the asphalt is set at 100% and the imperviousness of the concrete sidewalks/walkways is set at 90%. Windsong at Rock Creek Final Drainage Report 15 All areas outside the parking lot, building and sidewalks are assumed to be lawn with an imperviousness set at 5%. SUB-BASIN C5 Sub-basin C5 consists of 0.05 acres and is located on the south side of the subject property. The flows are directed offsite and will flow down to the existing curb along Rock Creek Drive roadway. The proposed private roadway creates sheet flow south of the high point and causes the runoff to flow to the proposed concrete pan. The existing curb will then direct the runoff east of the site. The slope of the flow from the sidewalk is approximately 2.0% and the slope of the roadway is approximately 3.0%. The imperviousness of the asphalt is set at 100% and the imperviousness of the concrete sidewalks/walkways is set at 90%. All areas outside the parking lot, building and sidewalks are assumed to be lawn with an imperviousness set at 5%. SUB-BASIN C6 Sub-basin C6 consists of 0.20 acres and is located on the east side of the subject property. The sub-basin includes the private roadway. The runoff sheet flows east to the flow line and then is routed to the sump inlet at the low point in the middle of the curb. The collected runoff is piped west to the proposed sand filter Pond C before being piped to the Detention Pond A. The slope of the roadway cross slope is approximately 2.0% with a longitudinal slope ranging from 0.5% to 2.0%. The cross slope of the sidewalk and lawns are approximately 2.0% and the slope from the berm is approximately 25%. The imperviousness of the asphalt is set at 100% and the imperviousness of the concrete sidewalks/walkways is set at 90%. All areas outside the parking lot, building and sidewalks are assumed to be lawn with an imperviousness set at 5%. Windsong at Rock Creek Final Drainage Report 16 DRAINAGE DESIGN CRITERIA REGULATIONS This report was prepared to meet or exceed the City of Fort Collins stormwater criteria. The City of Fort Collins Storm Drainage Design Criteria and Construction Manual (with all current 2011 Revisions)(FCSDDCCM) and the Urban Drainage Flood Control District’s (UDFCD) Drainage Criteria Manual (USDCM) Volumes 1, 2 and 3 were referenced as guidelines for this design. MINIMIZATION OF THE DCIA Volume reduction is an important part of the Four Step Process and is fundamental to effective stormwater management. Per City criteria, a minimum of 50 percent of new impervious surface area must be treated by a Low-Impact Development (LID) best management practice (BMP). The proposed LID BMPs will have the effect of slowing runoff through the site lot and increasing infiltration and rainfall interception by encouraging infiltration and careful selection of vegetative cover. The improvements will decrease the runoff coefficient from the site and are expected to have no adverse impact on the timing, quantity, or quality of stormwater runoff. Site-specific LID BMPs are discussed in the following sections of this report and an illustrative LID/Surface Map is provided in Appendix E. DEVELOPMENT CRITERIA REFERENCE AND CONSTRAINTS The master drainage report for the Windsong at Rock Creek site is the Final Drainage and Erosion Control Study for Harmony Technology Park Site Master Plan, Fort Collins, Colorado, prepared by Stantec Consulting Inc., and dated May 21, 2008. HYDROLOGIC CRITERIA The rational method was performed to calculate the peak runoff rates for each basin. Weighted percent imperviousness and weighted runoff coefficients were calculated for each basin using USDCM Tables 6-4 and 6-5 based on Natural Resources Conservation Service (NRCS) Type C hydrologic soil classification and surface characteristics of each basin. The time of concentration was calculated using USDCM Equation 6-2 and the intensity was calculated using the corresponding storm rainfall depth and USDCM Equation RA-3. The City of Fort Collins area has 2-year, 1-hour rainfall depth of 0.82 inches and a 100- year, 1-hour rainfall depth of 2.86 inches. These depths do account for the 1997 adjusted rainfall depths. Windsong at Rock Creek Final Drainage Report 17 HYDRAULIC CRITERIA This report demonstrates that the proposed stormwater detention concept is able to reduce the 100- year developed condition flows to the 2-year historical release rates; thereby satisfying the City’s Reasonable Use requirements. The Rational Formula-based Federal Aviation Administration (FAA) method is used to size the detention pond in accordance with City criteria, as the tributary area is less than 20 acres in size. The water quality capture volume is added to the minor and major detention volumes. An overflow spillway is required at the 100-year water surface elevation, set to flow at no more than six inches of depth at the peak pond inflow rate, and one foot of freeboard is provided from the spillway crest to the top of pond. The ultimate Windsong at Rock Creek storm drainage system will be designed to convey the minor and major storm events through the property with the proposed inlets, storm sewer pipes, and swales for the flows being calculated by this report. Per the requirements provided by the City of Fort Collins Storm Drainage Design Criteria and Construction Manual, all inlets and storm pipes will be designed to convey the 100-year storm flows. During the major storm event, the developed condition 100-year storm, the accumulated water depth in the ponds will be held to a maximum level in the ponds of one- foot below all building finished floor elevations. This drainage report demonstrates that the flow rate released downstream is less than would historically be experienced, and that the effects of erosion and sediment transport are lessened through increased infiltration the source. FLOODPLAIN REGULATIONS COMPLIANCE The Windsong at Rock Creek site is not located in a regulatory floodplain. MODIFICATIONS OF CRITERIA No modifications to City criteria are proposed herein. No variances from City criteria are sought with this PDP Drainage Report. Windsong at Rock Creek Final Drainage Report 18 DRAINAGE FACILITY DESIGN GENERAL CONCEPT The proposed improvements to the Windsong site will result in developed condition runoff being conveyed around the proposed building and to the east via storm sewer and surface flow. Low-impact development best management practices are proposed to improve the quality of runoff and aid in reducing peak flows. Specifically, permeable pavement systems are proposed for portions of the parking lot and drive aisle, and sand filters are on the east and southwest sides of the site to improve water quality. Runoff from the site is captured in inlets located in the parking lot and in open areas adjacent to the building, as well as in the patio courtyard areas. Runoff is conveyed in storm sewers in south and easterly directions to the proposed pond at the south end of the site. Secondly, surface overflow paths have been provided, such that the 100-year storm flows remain at least one foot below the finished floor elevation in a fully clogged inlet condition. WATER QUALITY/ DETENTION FACILITIES There currently exists no storm drain outfall that allows the site flows to reach the existing storm drain system at Rock Creek Drive and Technology Parkway. Therefore, an extended detention basin has been proposed in lieu of any regional detention located near Rock Creek Drive and Technology Parkway. The onsite detention ponds will provide water quality treatment and storm peak attenuation, and will release at the 2-year historic discharge to a proposed outfall pipe on the south end of the Harmony Park site. See Appendix C. Water quality will be provided for the site through the use of LIDs. Detention will be provided for the site through the proposed Detention Ponds A and B on the southern edge of the site. In a major storm situation, the stormwater in the Pond A can back up into Pond B and allows the ponds to be considered one detention pond. The proposed detention pond will detain the 100 year flows from the site and release at the 2 year historic release rate to the southeast corner of the property. The 100 yr water surface elevation and the overflow weir elevation for the pond is at 4920.55. The proposed pond also has 1 foot of freeboard above this elevation. Windsong at Rock Creek Final Drainage Report 19 The most recent version of the UD-Detention software (Version 2.35, January 2015) was used to determine the ultimate detention volume requirements. Per City of Fort Collins requirements, one-foot of freeboard is provided in this detention configuration. Since 100% of the site that is tributary to the ponds is treated by LID water quality is not need in the pond. The design capacity of the onsite pond is the 100-year runoff volume as determined by the FAA method in accordance with City criteria for a site less than five acres. See Table 1, below, for detention pond sizing and release rates. Table1: Detention Pond Values Pond Storage Volume Required (acre-ft) WQCV Required (acre-ft) 100-yr WQCV Emergency Overflow Top of Pond Volume WS Release Volume WS WS Release Elevation (acres) (ft) (cfs) (acres) (ft) (ft) (cfs) (ft) Pond A 0.452 - 0.45 4920.55 0.5 - - 4920.55 21.7 4921.55 Pond B 0.205 0.023 0.205 4920.55 4.5 0.023 4918.47 - - 4921.00 Pond C - 0.078 - - 14.3 0.078 4919.02 - - 4920.00 Total 0.657 0.101 - - - - - - - - LOW IMPACT DEVELOPMENT A minimum of 50 percent of new impervious surface area is treated by a Low-Impact Development (LID) best management practice (BMP) in accordance with City criteria. The BMPs proposed for the Windsong site include permeable interlocking concrete pavers, and sand filters for water quality treatment. Of the total 2.07 acres of impervious area, 1.80 acres is treated by LIDs (93.1%). Since more than 75% of the site is treated by LID the minimum threshold of permeable pavers for new parking is not required. An illustrative LID/ Surface Map is provided in Appendix E as well as sizing of the LIDs/BMPs are provided in Appendix D. Windsong at Rock Creek Final Drainage Report 20 Table2: LID Requirements 50% On-Site Treatment by LID Requirement New Impervious Area 90,342 sq. ft. Required Minimum Impervious Area to be Treated 45,171 sq. ft. (=50% of new impervious area) Area of Paver Section #1 7,322 sq. ft. Run-on area for Paver Section #1 (1.0:1) 8,534 sq. ft. Area of Sand Filter Pond C 7,234 sq. ft. Impervious Area Treated by LID Treatment Method #2- Sand Filter Pond C (8.0:1) 58,174 sq. ft. Area of Sand Filter Pond B 5,813 sq. ft. Impervious Area Treated by LID Treatment Method #3- Sand Filter Pond B (3.0:1) 17,402 sq. ft. Total Impervious Area Treated 84,110 sq. ft. Actual % of New Impervious Area Treated 93.1 % Porous Pavement Requirement New Pavement Area 33,178 sq. ft. Required Minimum Area of Porous Pavement (=25% of new pavement area) 8,295 sq. ft. Area of Paver Section #1 7,322 sq. ft. Total Porous Pavement Area 7,322 sq. ft. Actual % of Porous Pavement Provided 22.1 % Windsong at Rock Creek Final Drainage Report 21 CONCLUSIONS COMPLIANCE WITH STANDARDS The hydrologic and water quality calculations were performed using the required methods as outlined in the City of Fort Collins Amendments to the Urban Drainage and Flood Control District Criteria Manual. The proposed drainage improvements meet or exceed the City’s requirements. This report exhibits that both the storm water systems meet or exceed the requirements set forth in the City of Fort Collins “Storm Drainage Criteria Manual and Construction Standards” and addenda. DRAINAGE CONCEPT The proposed concept for the development of the Windsong at Rock Creek site involves surface flows and piping of developed conditions flows to a proposed onsite detention pond. LID site enhancements will treat the site runoff at the source before allowing the runoff to be conveyed to the proposed detention pond. Offsite flows from the north will be conveyed through the site and directly released at the, quality and rate as historically passed through the site. The existing conditions drainage patterns are maintained in the proposed and future conditions. The proposed improvements will have no adverse impacts on the flow rate, character, or quality of runoff leaving the site. Windsong at Rock Creek Final Drainage Report 22 REFERENCES East Harmony Portion of McClellands Basin 100-Year Master Plan, Icon Inc., August 1999. Final Drainage and Erosion Control Study for Harmony Technology Park Site Master Plan, Fort Collins, Colorado; Stantec Consulting Inc., May 21, 2008. Hydrologic Group Rating for Larimer County Area, Colorado; USDA-Natural Resources Conservation Service, National Cooperative Soil Survey, July 21, 2010. Storm Drainage Criteria Manual and Construction Standards; City of Fort Collins Storm Water Utility, City of Fort Collins, Colorado, January 1997. Urban Storm Drainage Criteria Manual (Volumes 1, 2, and 3); Urban Drainage and Flood Control District, June 2001. Windsong at Rock Creek Final Drainage Report APPENDIX A – FIGURES ;-2(732+ %8 63'/ '6))/ 7-8) ;-2(732+ %8 63'/ '6))/ 7-8) Windsong at Rock Creek Final Drainage Report APPENDIX B – HYDROLOGIC CALCULATIONS Subdivision: 0 Project Name: Windsong Location: Fort Collins Project No.: Calculated By: BAB Checked By: 0 Date: 2/23/16 FINAL BASIN D.A. Hydrologic Impervious C2 L S o t i L t S o K VEL. t t COMP. t c TOTAL Urbanized t c t c ID (ac) Soils Group (%) (ft) (%) (min) (ft) (%) (ft/s) (min) (min) LENGTH (ft) (min) (min) EX1 2.99 C 2% 0.10 300 0.7% 35.2 50 0.7% 7.0 0.6 1.4 36.6 350.0 23.3 23.3 EX2 0.17 C 2% 0.10 30 0.5% 12.4 146 0.5% 20.0 1.4 1.7 14.2 176.0 21.0 14.2 EX3 0.19 C 2% 0.10 17 2.4% 5.6 100 0.5% 20.0 1.4 1.2 6.8 117.0 19.9 6.8 OF1 2.30 C 2% 0.10 300 0.8% 33.7 100 0.8% 7.0 0.6 2.7 36.3 400.0 23.7 23.7 * C values based on Table RO-11 NOTES: t c =t i +t t (Equation 6-2) t i = (0.395*(1.1 - C 5)*(L)^0.5)/((So )^0.33) (Equation 6-3) t i = overland (initial) flow time (minutes) K S = Average Slope along the overland flow path, ft/ft 2.5 t t =L/(60K*(S o)^0.5 (Equation 6-4) 5 t t = channelized flow time (minutes) 7 S = waterway slope, ft/ft 10 V t = travel time velocity (ft/sec) = K*S o^0.5 15 20 First Design Point Time of Concentration: t c =(18-15*i )+L/(60*(24*i +12)*(S o)^0.5) (Equation 6-5) i = imperviousness (expressed as a decimal) t c is lesser of Equation 6-2 and Equation 6-5. For Urbanized basins a minimum t c of 5.0 minutes is required. For non-urbanized basins a minimum t c of 10.0 minutes is required. Paved areas and shallow paved swales DATA (Ti) (T t) (URBANIZED BASINS) Table 6-2. NRCS Conveyance Factors, K Type of Land Surface Heavy Meadow Tillage/field Short pasture and lawns Nearly bare ground Grassed waterway STANDARD FORM SF-2 TIME OF CONCENTRATION 39727.00 SUB-BASIN INITIAL/OVERLAND TRAVEL TIME tc CHECK X:\3970000.all\3972700\Excel\Drainage\3972700 Drainage_Calcs_v2.0.xlsm Page 1 of 1 2/16/2016 Project Name: Windsong Subdivision: 0 Project No.: Location: Fort Collins Calculated By: BAB Design Storm: Checked By: 0 Date: TRAVEL TIME STREET Design Point Basin ID Area (Ac) Runoff Coeff. tc (min) C*A (Ac) I (in/hr) Q (cfs) tc (min) C*A (Ac) I (in/hr) Q (cfs) Slope (%) Street Flow (cfs) Design Flow (cfs) Slope (%) Pipe Size (inches) Length (ft) Velocity (fps) tt (min) REMARKS 1 OF1 2.30 0.10 23.7 0.23 1.47 0.3 EX1 2.99 0.10 23.3 0.30 1.49 0.4 2 EX2 0.17 0.10 14.2 0.02 1.91 0.03 3 EX3 0.19 0.10 6.8 0.02 2.55 0.05 23.3 0.34 1.49 0.5 DIRECT RUNOFF TOTAL RUNOFF STREET PIPE STANDARD FORM SF-3 STORM DRAINAGE SYSTEM DESIGN (RATIONAL METHOD PROCEDURE) 39727.00 2-Year 2/23/16 X:\3970000.all\3972700\Excel\Drainage\3972700 Drainage_Calcs_v2.0.xlsm Page 1 of 1 2/16/2016 Subdivision: 0 Project Name: Windsong Location: Fort Collins Project No.: Calculated By: BAB Checked By: 0 Date: 4/20/16 A1 0.39 100% 0.13 32.7% 90% 0.04 9.3% 5% 0.13 1.7% 90% 0.09 20.9% 64.6% A2 0.50 100% 0.21 42.1% 90% 0.06 10.5% 5% 0.14 1.4% 90% 0.09 17.1% 71.1% A3 0.08 100% 0.04 45.1% 90% 0.02 20.3% 5% 0.03 1.6% 90% 0.00 0.0% 67.0% A4 0.18 100% 0.00 0.0% 90% 0.06 27.5% 5% 0.07 1.8% 90% 0.06 29.9% 59.1% A5 0.24 100% 0.00 0.0% 90% 0.06 20.5% 5% 0.00 0.0% 90% 0.19 69.5% 90.0% A6 0.24 100% 0.00 0.0% 90% 0.06 20.5% 5% 0.00 0.0% 90% 0.19 69.5% 90.0% A7 0.10 100% 0.00 0.0% 90% 0.04 39.2% 5% 0.00 0.0% 90% 0.06 50.8% 90.0% A8 0.19 100% 0.00 0.0% 90% 0.00 0.0% 5% 0.19 4.9% 90% 0.00 1.9% 6.8% A9 0.09 100% 0.00 4.1% 90% 0.00 2.9% 5% 0.02 1.0% 90% 0.06 64.5% 72.6% A10 0.02 100% 0.00 20.9% 90% 0.00 15.2% 5% 0.01 3.1% 90% 0.00 0.0% 39.2% A11 0.12 100% 0.05 42.9% 90% 0.03 23.9% 5% 0.01 0.6% 90% 0.02 16.8% 84.1% A12 0.29 100% 0.11 36.4% 90% 0.03 8.0% 5% 0.16 2.7% 90% 0.00 0.0% 47.2% B1 0.04 100% 0.00 0.0% 90% 0.00 0.0% 5% 0.04 4.5% 90% 0.00 9.2% 13.7% B2 0.21 100% 0.00 0.0% 90% 0.02 8.3% 5% 0.19 4.5% 90% 0.00 0.0% 12.8% B3 0.08 100% 0.00 0.0% 90% 0.00 0.0% 5% 0.02 1.5% 90% 0.06 63.6% 65.1% B4 0.14 100% 0.04 26.8% 90% 0.04 24.7% 5% 0.03 1.0% 90% 0.04 22.9% 75.5% B5 0.02 100% 0.00 14.6% 90% 0.00 1.4% 5% 0.02 4.2% 90% 0.00 0.0% 20.2% C1 0.06 100% 0.00 0.0% 90% 0.01 20.7% 5% 0.04 3.8% 90% 0.00 0.0% 24.6% C2 0.13 100% 0.00 0.0% 90% 0.03 22.6% 5% 0.10 3.7% 90% 0.00 0.0% 26.3% C3 0.10 100% 0.00 0.0% 90% 0.03 29.7% 5% 0.06 3.3% 90% 0.00 0.0% 33.1% C4 0.09 100% 0.00 0.0% 90% 0.02 17.7% 5% 0.07 4.0% 90% 0.00 0.0% 21.8% C5 0.05 100% 0.01 33.1% 90% 0.02 46.4% 5% 0.01 0.8% 90% 0.00 0.0% 80.3% C6 0.22 100% 0.15 68.3% 90% 0.06 25.6% 5% 0.01 0.2% 90% 0.00 0.0% 94.1% TOTAL 3.57 60.3% TOTAL Pond A & B 3.16 63.9% TOTAL Pond B Basin B1-B3, A4, & A5 0.76 54.1% TOTAL Pond C Basin A1-A3,A6-A9,C6 1.82 69.2% Lawns Weighted % Imp. % Imp. Area (ac) 39727.00 COMPOSITE % IMPERVIOUS CALCULATIONS Weighted % Imp. Basins Total Weighted % Basin ID Total Area (ac) % Imp. Area (ac) Imp. Roofs % Imp. Area (ac) Weighted % Imp. Paved Roads Concrete Walks/Pavement % Imp. Area (ac) Weighted % Imp. X:\3970000.all\3972700\Excel\Drainage\3972700 Drainage_Calcs_v2.0.xlsm Page 1 of 1 4/19/2016 Subdivision: 0 Project Name: Windsong Location: Fort Collins Project No.: Calculated By: BAB Checked By: 0 Date: 4/20/16 A1 0.39 0.95 0.13 0.31 0.95 0.04 0.10 0.10 0.13 0.03 0.95 0.09 0.22 0.66 A2 0.50 0.95 0.21 0.40 0.95 0.06 0.11 0.10 0.14 0.03 0.95 0.09 0.18 0.72 A3 0.11 0.95 0.07 0.56 0.95 0.02 0.16 0.10 0.03 0.02 0.95 0.00 0.00 0.75 A4 0.18 0.95 0.00 0.00 0.95 0.06 0.29 0.10 0.07 0.04 0.95 0.06 0.32 0.64 A5 0.24 0.95 0.00 0.00 0.95 0.06 0.22 0.10 0.00 0.00 0.95 0.19 0.73 0.95 A6 0.24 0.95 0.00 0.00 0.95 0.06 0.22 0.10 0.00 0.00 0.95 0.19 0.73 0.95 A7 0.10 0.95 0.00 0.00 0.95 0.04 0.41 0.10 0.00 0.00 0.95 0.06 0.54 0.95 A8 0.19 0.95 0.00 0.00 0.95 0.00 0.00 0.10 0.19 0.10 0.95 0.00 0.02 0.12 A9 0.09 0.95 0.00 0.04 0.95 0.00 0.03 0.10 0.02 0.02 0.95 0.06 0.68 0.77 A10 0.02 0.95 0.00 0.20 0.95 0.00 0.16 0.10 0.01 0.06 0.95 0.00 0.00 0.42 A11 0.12 0.95 0.05 0.41 0.95 0.03 0.25 0.10 0.01 0.01 0.95 0.02 0.18 0.85 A12 0.29 0.95 0.11 0.35 0.95 0.03 0.08 0.10 0.16 0.05 0.95 0.00 0.00 0.49 B1 0.04 0.95 0.00 0.00 0.95 0.00 0.00 0.10 0.04 0.09 0.95 0.00 0.10 0.19 B2 0.21 0.95 0.00 0.00 0.95 0.02 0.09 0.10 0.19 0.09 0.95 0.00 0.00 0.18 B3 0.08 0.95 0.00 0.00 0.95 0.00 0.00 0.10 0.02 0.03 0.95 0.06 0.67 0.70 B4 0.14 0.95 0.04 0.25 0.95 0.04 0.26 0.10 0.03 0.02 0.95 0.04 0.24 0.78 B5 0.02 0.95 0.00 0.14 0.95 0.00 0.01 0.10 0.02 0.08 0.95 0.00 0.00 0.24 C1 0.06 0.95 0.00 0.00 0.95 0.01 0.22 0.10 0.04 0.08 0.95 0.00 0.00 0.30 C2 0.13 0.95 0.00 0.00 0.95 0.03 0.24 0.10 0.10 0.07 0.95 0.00 0.00 0.31 C3 0.10 0.95 0.00 0.00 0.95 0.03 0.31 0.10 0.06 0.07 0.95 0.00 0.00 0.38 C4 0.09 0.95 0.00 0.00 0.95 0.02 0.19 0.10 0.07 0.08 0.95 0.00 0.00 0.27 C5 0.05 0.95 0.01 0.31 0.95 0.02 0.49 0.10 0.01 0.02 0.95 0.00 0.00 0.82 C6 0.20 0.95 0.12 0.60 0.95 0.06 0.31 0.10 0.01 0.00 0.95 0.00 0.00 0.92 TOTAL 3.57 0.63 Weighted C2 Runoff Coefficient COMPOSITE % IMPERVIOUS CALCULATIONS 39727.00 Paved Roads Concrete Walks/Pavement Lawns Roofs Basins Total Weighted C2 Basin ID Runoff Coefficient Total Area (ac) Area (ac) Weighted C2 Runoff Coefficient Area (ac) Area (ac) Weighted C2 Runoff Coefficient Area (ac) Weighted C2 X:\3970000.all\3972700\Excel\Drainage\3972700 Drainage_Calcs_v2.0.xlsm Page 1 of 1 4/19/2016 Subdivision: 0 Project Name: Windsong Location: Fort Collins Project No.: Calculated By: BAB Checked By: 0 Date: 4/20/16 FINAL BASIN D.A. Hydrologic Impervious C2 C100 L S o t i L t S o K VEL. t t COMP. t c TOTAL Urbanized t c t c ID (ac) Soils Group (%) (ft) (%) (min) (ft) (%) (ft/s) (min) (min) LENGTH (ft) (min) (min) A1 0.39 C 65% 0.66 0.83 95 8.3% 3.8 74 0.6% 20.0 1.5 0.8 4.6 169.0 9.6 5.0 A2 0.50 C 71% 0.72 0.90 45 1.9% 3.7 148 0.5% 20.0 1.4 1.7 5.5 193.0 8.9 5.5 A3 0.11 C 67% 0.75 0.93 20 25.0% 1.0 25 0.5% 20.0 1.4 0.3 1.3 45.0 8.3 5.0 A4 0.18 C 59% 0.64 0.80 11 16.3% 1.1 152 1.6% 20.0 2.5 1.0 2.1 163.0 9.9 5.0 A5 0.24 C 90% 0.95 1.00 0 13.0% 0.0 117 0.5% 20.0 1.4 1.4 1.4 117.0 5.3 5.0 A6 0.24 C 90% 0.95 1.00 0 13.0% 0.0 121 0.5% 20.0 1.4 1.4 1.4 121.0 5.3 5.0 A7 0.10 C 90% 0.95 1.00 45 20.0% 0.7 75 1.0% 20.0 2.0 0.6 1.3 120.0 5.1 5.0 A8 0.19 C 7% 0.12 0.15 5 16.0% 1.6 3 1.0% 20.0 2.0 0.0 1.6 8.0 17.1 5.0 A9 0.09 C 73% 0.77 0.96 5 8.0% 0.7 65 2.0% 20.0 2.8 0.4 1.1 70.0 7.4 5.0 A10 0.02 C 39% 0.42 0.53 25 4.2% 3.8 0 1.0% 20.0 2.0 0.0 3.8 25.0 12.3 5.0 A11 0.12 C 84% 0.85 1.00 48 2.3% 2.4 38 0.5% 20.0 1.4 0.4 2.8 86.0 6.0 5.0 A12 0.29 C 47% 0.49 0.61 40 8.5% 3.5 17 2.3% 20.0 3.0 0.1 3.6 57.0 11.2 5.0 B1 0.04 C 14% 0.19 0.23 11 16.3% 2.2 62 2.0% 20.0 2.8 0.4 2.5 73.0 16.5 5.0 B2 0.21 C 13% 0.18 0.22 46 5.4% 6.5 90 1.2% 20.0 2.2 0.7 7.2 136.0 17.4 7.2 B3 0.08 C 65% 0.70 0.88 9 4.5% 1.3 81 2.8% 20.0 3.3 0.4 1.7 90.0 8.6 5.0 B4 0.14 C 75% 0.78 0.97 44 2.9% 2.7 28 2.3% 20.0 3.0 0.2 2.9 72.0 6.9 5.0 B5 0.02 C 20% 0.24 0.30 41 2.7% 7.2 0 1.0% 20.0 2.0 0.0 7.2 41.0 15.4 7.2 C1 0.06 C 25% 0.30 0.37 16 2.0% 4.6 0 2.0% 20.0 2.8 0.0 4.6 16.0 14.4 5.0 C2 0.13 C 26% 0.31 0.39 52 7.3% 5.3 0 2.0% 20.0 2.8 0.0 5.3 52.0 14.4 5.3 C3 0.10 C 33% 0.38 0.48 14 2.2% 3.7 60 0.5% 20.0 1.4 0.7 4.5 74.0 13.9 5.0 C4 0.09 C 22% 0.27 0.33 13 2.6% 4.0 0 0.5% 20.0 1.4 0.0 4.0 13.0 14.9 5.0 C5 0.05 C 80% 0.82 1.00 35 25.0% 1.0 30 2.0% 20.0 2.8 0.2 1.2 65.0 6.2 5.0 C6 0.20 C 94% 0.92 1.00 22 2.6% 1.1 0 0.5% 20.0 1.4 0.0 1.1 22.0 4.0 5.0 * C-value determined from composite C value and Table RO-11 and RO-12 NOTES: t c =t i +t t (Equation 6-2) t i = (0.395*(1.1 - C 5)*(L)^0.5)/((So )^0.33) (Equation 6-3) t i = overland (initial) flow time (minutes) K S = Average Slope along the overland flow path, ft/ft 2.5 t t =L/(60K*(S o)^0.5 (Equation 6-4) 5 t t = channelized flow time (minutes) 7 S = waterway slope, ft/ft 10 V t = travel time velocity (ft/sec) = K*S o^0.5 15 20 First Design Point Time of Concentration: t c =(18-15*i )+L/(60*(24*i +12)*(S o)^0.5) (Equation 6-5) i = imperviousness (expressed as a decimal) t c is lesser of Equation 6-2 and Equation 6-5. For Urbanized basins a minimum t c of 5.0 minutes is required. Project Name: Windsong Subdivision: 0 Project No.: Location: Fort Collins Calculated By: BAB Design Storm: Checked By: 0 Date: TRAVEL TIME STREET Design Point Basin ID Area (Ac) Runoff Coeff. tc (min) C*A (Ac) I (in/hr) Q (cfs) tc (min) C*A (Ac) I (in/hr) Q (cfs) Slope (%) Street Flow (cfs) Design Flow (cfs) Slope (%) Pipe Size (inches) Length (ft) Velocity (fps) tt (min) REMARKS area sump inlet 1 A1 0.39 0.66 5.0 0.26 2.78 0.7 piped to DP2 area sump inlet 2 A2 0.50 0.72 5.5 0.36 2.71 1.0 5.5 0.62 2.71 1.7 1.7 0.5 21 108 3.3 0.5 piped to DP8 Pond C 5' Type R Sump Inlet 3a C6 0.20 0.92 5.0 0.18 2.78 0.5 0.5 0.5 12 26 2.4 0.2 piped to DP3 5' Type R Sump Inlet 3 A3 0.11 0.75 5.0 0.09 2.78 0.3 5.2 0.27 2.76 0.7 0.7 0.5 12 10 2.7 0.1 piped to DP8 Pond C area sump inlets 6 A6 0.24 0.95 5.0 0.23 2.78 0.6 0.6 0.5 12 120 2.6 0.8 piped to DP7 area sump inlets 7 A7 0.10 0.95 5.0 0.09 2.78 0.3 5.8 0.32 2.67 0.9 0.9 0.5 12 15 2.8 0.1 piped to DP8 Pond C area sump inlets 9 A9 0.09 0.77 5.0 0.07 2.78 0.2 0.2 0.5 12 50 1.9 0.4 piped to DP8 Pond C Sand Filter/ Pond C 8 A8 0.19 0.12 5.0 0.02 2.78 0.1 6.0 1.30 2.64 3.4 3.4 0.5 21 110 4.1 0.5 piped to DP12 Pond A area sump inlets 5 A5 0.24 0.95 5.0 0.23 2.78 0.6 0.6 0.5 12 120 2.6 0.8 piped to DP4 area sump inlets 4 A4 0.18 0.64 5.0 0.12 2.78 0.3 5.8 0.35 2.67 0.9 0.9 0.5 12 75 2.9 0.4 piped to DP13 area sump inlets 13 B1 0.04 0.19 5.0 0.01 2.78 0.03 6.2 0.36 2.62 0.9 0.9 0.5 12 50 2.9 0.3 piped to DP14 Pond B area sump inlets 15 B3 0.08 0.70 5.0 0.06 2.78 0.2 0.2 0.5 12 60 1.7 0.6 piped to PD14 Pond B WQ Detention Pond B 14 B2 0.21 0.18 7.2 0.04 2.50 0.1 7.2 0.46 2.50 1.2 1.2 0.5 12 10 3.1 0.1 piped to inlet at DP16 5' Type R Sump Inlet 16 B4 0.14 0.78 5.0 0.11 2.78 0.3 7.2 0.57 2.50 1.4 1.4 0.5 12 40 3.3 0.2 piped to DP17 area sump inlet 17 B5 0.02 0.24 7.2 0.00 2.50 0.0 7.4 0.57 2.47 1.4 1.4 0.5 12 50 3.3 0.3 piped to DP11 area sump inlet 10 A10 0.02 0.42 5.0 0.01 2.78 0.03 0.03 0.5 12 24 0.9 0.4 piped to DP11 STANDARD FORM SF-3 STORM DRAINAGE SYSTEM DESIGN (RATIONAL METHOD PROCEDURE) Project Name: Windsong Subdivision: 0 Project No.: Location: Fort Collins Calculated By: BAB Design Storm: Checked By: 0 Date: TRAVEL TIME STREET Design Point Basin ID Area (Ac) Runoff Coeff. tc (min) C*A (Ac) I (in/hr) Q (cfs) tc (min) C*A (Ac) I (in/hr) Q (cfs) Slope (%) Street Flow (cfs) Design Flow (cfs) Slope (%) Pipe Size (inches) Length (ft) Velocity (fps) tt (min) REMARKS area sump inlet 1 A1 0.39 0.83 5.0 0.32 9.70 3.1 piped to DP2 area sump inlet 2 A2 0.50 0.90 5.5 0.45 9.46 4.3 5.5 0.77 9.46 7.3 7.3 0.5 21 108 5.0 0.4 piped to DP8 Pond C 5' Type R Sump Inlet 3a C6 0.20 1.00 5.0 0.20 9.70 1.9 1.9 0.5 12 26 3.5 0.1 piped to DP3 5' Type R Sump Inlet 3 A3 0.11 0.93 5.0 0.11 9.70 1.1 5.1 0.31 9.64 3.0 3.0 0.5 12 10 3.8 0.0 piped to DP8 Pond C area sump inlets 6 A6 0.24 1.00 5.0 0.24 9.70 2.3 2.3 0.5 12 120 3.6 0.6 piped to DP7 area sump inlets 7 A7 0.10 1.00 5.0 0.10 9.70 1.0 5.6 0.34 9.43 3.2 3.2 0.5 12 15 4.1 0.1 piped to DP8 Pond C area sump inlets 9 A9 0.09 0.96 5.0 0.09 9.70 0.9 0.9 0.5 12 50 2.9 0.3 piped to DP8 Pond C Sand Filter/ Pond C 8 A8 0.19 0.15 5.0 0.03 9.70 0.3 5.8 1.54 9.29 14.3 14.3 0.5 21 110 6.0 0.3 piped to DP12 Pond A area sump inlets 5 A5 0.24 1.00 5.0 0.24 9.70 2.3 2.3 0.5 12 120 3.6 0.6 piped to DP4 area sump inlets 4 A4 0.18 0.80 5.0 0.15 9.70 1.5 5.6 0.39 9.43 3.7 3.7 0.5 12 75 4.7 0.3 piped to DP13 area sump inlets 13 B1 0.04 0.23 5.0 0.01 9.70 0.1 5.8 0.40 9.30 3.7 3.7 0.5 12 50 4.7 0.2 piped to DP14 Pond B area sump inlets 15 B3 0.08 0.88 5.0 0.07 9.70 0.7 0.7 0.5 12 60 2.7 0.4 piped to PD14 Pond B WQ Detention Pond B 14 B2 0.21 0.22 7.2 0.05 8.73 0.4 7.2 0.52 8.73 4.5 4.5 0.5 12 10 5.8 0.0 piped to inlet at DP16 5' Type R Sump Inlet 16 B4 0.14 0.97 5.0 0.14 9.70 1.4 7.2 0.66 8.72 5.8 5.8 0.5 12 40 7.3 0.1 piped to DP17 area sump inlet Windsong at Rock Creek Final Drainage Report APPENDIX C – HYDRAULIC CALCULATIONS Worksheet Protected Project: Inlet ID: Design Flow: ONLY if already determined through other methods: Minor Storm Major Storm (local peak flow for 1/2 of street OR grass-lined channel): *QKnown = 0.5 1.9 cfs * If you enter values in Row 14, skip the rest of this sheet and proceed to sheet Q-Allow or Area Inlet. Geographic Information: (Enter data in the blue cells): Subcatchment Area = Acres Percent Imperviousness = % NRCS Soil Type = A, B, C, or D Slope (ft/ft) Length (ft) Overland Flow = Channel Flow = Rainfall Information: Intensity I (inch/hr) = C1 * P 1 / ( C2 + Tc ) ^ C 3 Minor Storm Major Storm Design Storm Return Period, Tr = years Return Period One-Hour Precipitation, P1 = inches C1 = C2 = C3 = User-Defined Storm Runoff Coefficient (leave this blank to accept a calculated value), C = User-Defined 5-yr. Runoff Coefficient (leave this blank to accept a calculated value), C5 = Bypass (Carry-Over) Flow from upstream Subcatchments, Qb = 0.0 0.0 cfs Total Design Peak Flow, Q = 0.5 1.9 cfs <--- FILL IN THIS SECTION OR… FILL IN THE SECTIONS BELOW. <--- DESIGN PEAK FLOW FOR ONE-HALF OF STREET OR GRASS-LINED CHANNEL BY THE RATIONAL METHOD DIBC Drainage Improvements 5' Type R Sump Inlet DP3a Site is Urban Site is Non-Urban Show Details Site Type: Street Inlets Area Inlets in a Median Flows Developed For: Sump Inlet DP3a.xlsm, Q-Peak 4/19/2016, 11:59 AM Project: Inlet ID: Gutter Geometry (Enter data in the blue cells) Maximum Allowable Width for Spread Behind Curb TBACK = 23.0 ft Side Slope Behind Curb (leave blank for no conveyance credit behind curb) SBACK = 0.250 ft/ft Manning's Roughness Behind Curb (typically between 0.012 and 0.020) nBACK = 0.013 Height of Curb at Gutter Flow Line HCURB = 6.00 inches Distance from Curb Face to Street Crown TCROWN = 33.0 ft Gutter Width W = 2.00 ft Street Transverse Slope SX = 0.040 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 = 0.016 Minor Storm Major Storm Max. Allowable Spread for Minor & Major Storm TMAX = 18.0 18.0 ft Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX = 6.0 6.0 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 Major storm max. allowable capacity GOOD - greater than flow given on sheet 'Q-Peak' ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm) DIBC Drainage Improvements 5' Type R Sump Inlet DP3a (Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread) Minor storm max. allowable capacity GOOD - greater than flow given on sheet 'Q-Peak' Sump Inlet DP3a.xlsm, Q-Allow 4/19/2016, 12:00 PM Project = Inlet ID = Design Information (Input) MINOR MAJOR Type of Inlet 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 6.0 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) = 5.00 5.00 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 2.3-3.6) Cw (C) = 3.60 3.60 Curb Opening Orifice Coefficient (typical value 0.60 - 0.70) Co (C) = 0.67 0.67 MINOR MAJOR Total Inlet Interception Capacity (assumes clogged condition) Qa = 5.4 5.4 cfs Inlet Capacity IS GOOD for Minor and Major Storms (>Q PEAK) Q PEAK REQUIRED = 0.5 1.9 cfs INLET IN A SUMP OR SAG LOCATION DIBC Drainage Improvements 5' Type R Sump Inlet DP3a CDOT Type R Curb Opening H-Vert H-Curb W Lo (C) Lo (G) Wo WP Override Depths Sump Inlet DP3a.xlsm, Inlet In Sump 4/19/2016, 12:00 PM Worksheet Protected Project: Inlet ID: Design Flow: ONLY if already determined through other methods: Minor Storm Major Storm (local peak flow for 1/2 of street OR grass-lined channel): *QKnown = 0.3 1.1 cfs * If you enter values in Row 14, skip the rest of this sheet and proceed to sheet Q-Allow or Area Inlet. Geographic Information: (Enter data in the blue cells): Subcatchment Area = Acres Percent Imperviousness = % NRCS Soil Type = A, B, C, or D Slope (ft/ft) Length (ft) Overland Flow = Channel Flow = Rainfall Information: Intensity I (inch/hr) = C1 * P 1 / ( C2 + Tc ) ^ C 3 Minor Storm Major Storm Design Storm Return Period, Tr = years Return Period One-Hour Precipitation, P1 = inches C1 = C2 = C3 = User-Defined Storm Runoff Coefficient (leave this blank to accept a calculated value), C = User-Defined 5-yr. Runoff Coefficient (leave this blank to accept a calculated value), C5 = Bypass (Carry-Over) Flow from upstream Subcatchments, Qb = 0.0 0.0 cfs Total Design Peak Flow, Q = 0.3 1.1 cfs <--- FILL IN THIS SECTION OR… FILL IN THE SECTIONS BELOW. <--- DESIGN PEAK FLOW FOR ONE-HALF OF STREET OR GRASS-LINED CHANNEL BY THE RATIONAL METHOD DIBC Drainage Improvements 5' Type R Sump Inlet DP3 Site is Urban Site is Non-Urban Show Details Site Type: Street Inlets Area Inlets in a Median Flows Developed For: Sump Inlet DP3.xlsm, Q-Peak 4/19/2016, 11:57 AM Project: Inlet ID: Gutter Geometry (Enter data in the blue cells) Maximum Allowable Width for Spread Behind Curb TBACK = 23.0 ft Side Slope Behind Curb (leave blank for no conveyance credit behind curb) SBACK = 0.250 ft/ft Manning's Roughness Behind Curb (typically between 0.012 and 0.020) nBACK = 0.013 Height of Curb at Gutter Flow Line HCURB = 6.00 inches Distance from Curb Face to Street Crown TCROWN = 33.0 ft Gutter Width W = 2.00 ft Street Transverse Slope SX = 0.040 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 = 0.016 Minor Storm Major Storm Max. Allowable Spread for Minor & Major Storm TMAX = 18.0 18.0 ft Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX = 6.0 6.0 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 Major storm max. allowable capacity GOOD - greater than flow given on sheet 'Q-Peak' ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm) DIBC Drainage Improvements 5' Type R Sump Inlet DP3 (Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread) Minor storm max. allowable capacity GOOD - greater than flow given on sheet 'Q-Peak' Sump Inlet DP3.xlsm, Q-Allow 4/19/2016, 11:58 AM Project = Inlet ID = Design Information (Input) MINOR MAJOR Type of Inlet 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 6.0 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) = 5.00 5.00 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 2.3-3.6) Cw (C) = 3.60 3.60 Curb Opening Orifice Coefficient (typical value 0.60 - 0.70) Co (C) = 0.67 0.67 MINOR MAJOR Total Inlet Interception Capacity (assumes clogged condition) Qa = 5.4 5.4 cfs Inlet Capacity IS GOOD for Minor and Major Storms (>Q PEAK) Q PEAK REQUIRED = 0.3 1.1 cfs INLET IN A SUMP OR SAG LOCATION DIBC Drainage Improvements 5' Type R Sump Inlet DP3 CDOT Type R Curb Opening H-Vert H-Curb W Lo (C) Lo (G) Wo WP Override Depths Sump Inlet DP3.xlsm, Inlet In Sump 4/19/2016, 11:59 AM Worksheet Protected Project: Inlet ID: Design Flow: ONLY if already determined through other methods: Minor Storm Major Storm (local peak flow for 1/2 of street OR grass-lined channel): *QKnown = 0.3 1.2 cfs * If you enter values in Row 14, skip the rest of this sheet and proceed to sheet Q-Allow or Area Inlet. Geographic Information: (Enter data in the blue cells): Subcatchment Area = Acres Percent Imperviousness = % NRCS Soil Type = A, B, C, or D Slope (ft/ft) Length (ft) Overland Flow = Channel Flow = Rainfall Information: Intensity I (inch/hr) = C1 * P 1 / ( C2 + Tc ) ^ C 3 Minor Storm Major Storm Design Storm Return Period, Tr = years Return Period One-Hour Precipitation, P1 = inches C1 = C2 = C3 = User-Defined Storm Runoff Coefficient (leave this blank to accept a calculated value), C = User-Defined 5-yr. Runoff Coefficient (leave this blank to accept a calculated value), C5 = Bypass (Carry-Over) Flow from upstream Subcatchments, Qb = 0.0 0.0 cfs Total Design Peak Flow, Q = 0.3 1.2 cfs <--- FILL IN THIS SECTION OR… FILL IN THE SECTIONS BELOW. <--- DESIGN PEAK FLOW FOR ONE-HALF OF STREET OR GRASS-LINED CHANNEL BY THE RATIONAL METHOD DIBC Drainage Improvements 5' Type R Sump Inlet DP11 Site is Urban Site is Non-Urban Show Details Site Type: Street Inlets Area Inlets in a Median Flows Developed For: Sump Inlet DP11.xlsm, Q-Peak 4/19/2016, 12:01 PM Project: Inlet ID: Gutter Geometry (Enter data in the blue cells) Maximum Allowable Width for Spread Behind Curb TBACK = 23.0 ft Side Slope Behind Curb (leave blank for no conveyance credit behind curb) SBACK = 0.250 ft/ft Manning's Roughness Behind Curb (typically between 0.012 and 0.020) nBACK = 0.013 Height of Curb at Gutter Flow Line HCURB = 6.00 inches Distance from Curb Face to Street Crown TCROWN = 33.0 ft Gutter Width W = 2.00 ft Street Transverse Slope SX = 0.040 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 = 0.016 Minor Storm Major Storm Max. Allowable Spread for Minor & Major Storm TMAX = 18.0 18.0 ft Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX = 6.0 6.0 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 Major storm max. allowable capacity GOOD - greater than flow given on sheet 'Q-Peak' ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm) DIBC Drainage Improvements 5' Type R Sump Inlet DP11 (Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread) Minor storm max. allowable capacity GOOD - greater than flow given on sheet 'Q-Peak' Sump Inlet DP11.xlsm, Q-Allow 4/19/2016, 12:01 PM Project = Inlet ID = Design Information (Input) MINOR MAJOR Type of Inlet 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 6.0 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) = 5.00 5.00 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 2.3-3.6) Cw (C) = 3.60 3.60 Curb Opening Orifice Coefficient (typical value 0.60 - 0.70) Co (C) = 0.67 0.67 MINOR MAJOR Total Inlet Interception Capacity (assumes clogged condition) Qa = 5.4 5.4 cfs Inlet Capacity IS GOOD for Minor and Major Storms (>Q PEAK) Q PEAK REQUIRED = 0.3 1.2 cfs INLET IN A SUMP OR SAG LOCATION DIBC Drainage Improvements 5' Type R Sump Inlet DP11 CDOT Type R Curb Opening H-Vert H-Curb W Lo (C) Lo (G) Wo WP Override Depths Sump Inlet DP11.xlsm, Inlet In Sump 2/16/2016, 2:12 PM Worksheet Protected Project: Inlet ID: Design Flow: ONLY if already determined through other methods: Minor Storm Major Storm (local peak flow for 1/2 of street OR grass-lined channel): *QKnown = 0.3 1.4 cfs * If you enter values in Row 14, skip the rest of this sheet and proceed to sheet Q-Allow or Area Inlet. Geographic Information: (Enter data in the blue cells): Subcatchment Area = Acres Percent Imperviousness = % NRCS Soil Type = A, B, C, or D Slope (ft/ft) Length (ft) Overland Flow = Channel Flow = Rainfall Information: Intensity I (inch/hr) = C1 * P 1 / ( C2 + Tc ) ^ C 3 Minor Storm Major Storm Design Storm Return Period, Tr = years Return Period One-Hour Precipitation, P1 = inches C1 = C2 = C3 = User-Defined Storm Runoff Coefficient (leave this blank to accept a calculated value), C = User-Defined 5-yr. Runoff Coefficient (leave this blank to accept a calculated value), C5 = Bypass (Carry-Over) Flow from upstream Subcatchments, Qb = 0.0 0.0 cfs Total Design Peak Flow, Q = 0.3 1.4 cfs <--- FILL IN THIS SECTION OR… FILL IN THE SECTIONS BELOW. <--- DESIGN PEAK FLOW FOR ONE-HALF OF STREET OR GRASS-LINED CHANNEL BY THE RATIONAL METHOD DIBC Drainage Improvements 5' Type R Sump Inlet DP16 Site is Urban Site is Non-Urban Show Details Site Type: Street Inlets Area Inlets in a Median Flows Developed For: Sump Inlet DP16.xlsm, Q-Peak 4/19/2016, 12:02 PM Project: Inlet ID: Gutter Geometry (Enter data in the blue cells) Maximum Allowable Width for Spread Behind Curb TBACK = 23.0 ft Side Slope Behind Curb (leave blank for no conveyance credit behind curb) SBACK = 0.250 ft/ft Manning's Roughness Behind Curb (typically between 0.012 and 0.020) nBACK = 0.013 Height of Curb at Gutter Flow Line HCURB = 6.00 inches Distance from Curb Face to Street Crown TCROWN = 33.0 ft Gutter Width W = 2.00 ft Street Transverse Slope SX = 0.040 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 = 0.016 Minor Storm Major Storm Max. Allowable Spread for Minor & Major Storm TMAX = 18.0 18.0 ft Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX = 6.0 6.0 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 Major storm max. allowable capacity GOOD - greater than flow given on sheet 'Q-Peak' ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm) DIBC Drainage Improvements 5' Type R Sump Inlet DP16 (Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread) Minor storm max. allowable capacity GOOD - greater than flow given on sheet 'Q-Peak' Sump Inlet DP16.xlsm, Q-Allow 4/19/2016, 12:02 PM Project = Inlet ID = Design Information (Input) MINOR MAJOR Type of Inlet 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 6.0 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) = 5.00 5.00 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 2.3-3.6) Cw (C) = 3.60 3.60 Curb Opening Orifice Coefficient (typical value 0.60 - 0.70) Co (C) = 0.67 0.67 MINOR MAJOR Total Inlet Interception Capacity (assumes clogged condition) Qa = 5.4 5.4 cfs Inlet Capacity IS GOOD for Minor and Major Storms (>Q PEAK) Q PEAK REQUIRED = 0.3 1.4 cfs INLET IN A SUMP OR SAG LOCATION DIBC Drainage Improvements 5' Type R Sump Inlet DP16 CDOT Type R Curb Opening H-Vert H-Curb W Lo (C) Lo (G) Wo WP Override Depths Sump Inlet DP16.xlsm, Inlet In Sump 2/16/2016, 2:13 PM Plan View NE CO-12 CO-11 CO-6 CO-5 CO-4 CO-34 CO-39 CO-44 CO-45 O-9 FES 11-1 O-3 FES 3-1 O-2 FES 2-1 O-1a FES 1-3 DP1 INLET 1-6 INLET 1-5 DP8 PON C OUTLET FES 1-2 DP3 INLET 3-2 DP3A INLET 3-3 INLET 2A-3 INLET 2A-4 INLET 2A-1 INLET 2A-2 INLET 2-3 DP6 INLET 2-4 DP2 INLET 1-4 DP4 INLET 10A-1 DP5 INLET 10A-2 DP7 MH 2-2 27 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA Page 1 of 1 +1-203-755-1666 4/19/2016 Bentley StormCAD V8i (SELECTseries 3) 3972700StormCAD.stsw Bentley Systems, Inc. Haestad Methods Solution Center [08.11.03.84] Plan View SE CO-25 CO-21 CO-18 CO-17 CO-16 CO-15 CO-14 CO-13 CO-12 CO-11 CO-6 CO-5 CO-4 CO-38 CO-39 O-9 FES 11-1 O-4 FES 4-1 O-6 FES 6-1 O-3 FES 3-1 O-2 FES 2-1 O-1a FES 1-3 O-1 FES 1-1 O-5 EX. INLET 5-1 POND A OTLET 5-6 INLET 11-2 DP9 INLET 11-3 DP8 PON C OUTLET FES 1-2 DP3 INLET 3-2 DP3A INLET 3-3 INLET 2A-3 INLET 2A-4 INLET 2A-1 INLET 2A-2 INLET 2-3 DP6 INLET 2-4 DP11 INLET 4-2 DP10 INLET 7-1 DP12 INLET 6-2 DP7 MH 2-2 MH 5-5 MH 5-4 MH 5-3 MH 5-2 27 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA Page 1 of 1 +1-203-755-1666 4/19/2016 Bentley StormCAD V8i (SELECTseries 3) 3972700StormCAD.stsw Bentley Systems, Inc. Haestad Methods Solution Center [08.11.03.84] Plan View SW CO-25 CO-24 CO-22 CO-21 CO-14 CO-13 CO-12 CO-6 CO-5 CO-4 CO-35 CO-34 CO-37 CO-38 CO-39 O-9 FES 11-1 O-10 FES 10-1 O-4 FES 4-1 O-6 FES 6-1 O-3 FES 3-1 O-2 FES 2-1 O-1a FES 1-3 O-1 FES 1-1 DP15 INLET 10B-1 INLET 10-5 INLET 10-9 INLET 10-10 INLET 10-8 INLET 10-7 POND A OTLET 5-6 INLET 11-2 DP9 INLET 11-3 DP8 PON C OUTLET FES 1-2 INLET 2A-3 INLET 2A-4 INLET 2A-1 INLET 2A-2 INLET 2-3 DP6 INLET 2-4 DP13 INLET 10-2 INLET 10-3 INLET 10-4 DP4 INLET 10A-1 DP5 INLET 10A-2 DP17 INLET 8-1 POND B OUTLET 8-3 DP16 INLET 8-2 DP11 INLET 4-2 DP10 INLET 7-1 DP12 INLET 6-2 MH 10-6 DP7 MH 2-2 27 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA Page 1 of 1 +1-203-755-1666 4/19/2016 Bentley StormCAD V8i (SELECTseries 3) 3972700StormCAD.stsw Bentley Systems, Inc. Haestad Methods Solution Center [08.11.03.84] 2 Yr Results J-loss Coeff N-value Pipe Velocity Down (ft/s) Velocity Up (ft/s) Velocity Avg (ft/s) EGL Down (ft) EGL Up (ft) HGL Down (ft) HGL Up (ft) Invert Down (ft) Invert Up (ft) Line Slope (ft/ft) Line Length (ft) Line Size (in) Capacity (Design) (cfs) Flow (cfs) Label CO-2 1.70 8.60 18.0 108.5 0.004 4,917.14 4,916.71 4,917.63 4,917.16 4,917.81 4,917.39 3.79 3.39 3.79 0.010 0.700 CO-3 3.40 17.82 21.0 92.2 0.007 4,915.81 4,915.12 4,916.48 4,915.64 4,916.73 4,916.14 5.71 4.01 5.71 0.010 0.500 CO-4 0.30 3.26 12.0 50.4 0.005 4,919.60 4,919.35 4,919.83 4,919.56 4,919.90 4,919.66 2.59 2.26 2.59 0.010 1.500 CO-5 0.60 3.27 12.0 66.3 0.005 4,919.15 4,918.82 4,919.47 4,919.17 4,919.59 4,919.26 3.17 2.75 2.49 0.010 0.700 CO-6 0.90 3.23 12.0 22.6 0.005 4,918.62 4,918.51 4,919.02 4,918.87 4,919.17 4,919.06 3.52 3.09 3.52 0.010 1.000 CO-7 0.10 3.27 12.0 22.1 0.005 4,919.23 4,919.12 4,919.36 4,919.24 4,919.40 4,919.29 1.88 1.69 1.88 0.010 1.500 CO-8 0.10 3.21 12.0 20.9 0.005 4,918.92 4,918.82 4,919.17 4,919.17 4,919.17 4,919.17 1.85 0.67 0.41 0.010 0.700 CO-9 0.10 3.23 12.0 30.9 0.005 4,919.29 4,919.14 4,919.42 4,919.26 4,919.46 4,919.31 1.86 1.69 1.86 0.010 1.500 CO-10 0.10 3.27 12.0 24.1 0.005 4,918.94 4,918.82 4,919.16 4,919.17 4,919.17 4,919.17 1.88 0.76 0.41 0.010 0.700 CO-11 0.50 3.26 12.0 28.3 0.005 4,916.72 4,916.58 4,917.01 4,917.02 4,917.12 4,917.05 3.00 2.61 1.51 0.010 1.500 CO-12 0.70 3.18 12.0 16.9 0.005 4,916.58 4,916.50 4,916.93 4,916.82 4,917.06 4,916.98 3.25 2.87 3.24 0.010 0.700 CO-13 1.70 5.87 15.0 12.3 0.005 4,916.50 4,916.44 4,917.02 4,916.91 4,917.21 4,917.16 4.14 3.54 4.02 0.010 0.500 CO-14 0.50 8.77 18.0 164.9 0.007 4,913.40 4,912.25 4,913.66 4,912.53 4,913.75 4,912.60 2.69 2.41 2.24 0.013 0.500 CO-15 0.50 8.84 18.0 317.6 0.007 4,912.25 4,910.00 4,912.51 4,910.28 4,912.60 4,910.35 2.70 2.41 2.24 0.013 0.150 CO-16 0.50 8.84 18.0 301.8 0.007 4,910.00 4,907.86 4,910.26 4,908.10 4,910.35 4,908.22 2.70 2.41 2.70 0.013 0.150 CO-17 0.50 9.51 18.0 11.0 0.008 4,907.66 4,907.57 4,907.92 4,907.80 4,908.01 4,907.93 2.85 2.41 2.85 0.013 0.450 CO-18 0.50 74.94 42.0 9.0 0.006 4,905.57 4,905.52 4,905.78 4,905.72 4,905.85 4,905.80 2.21 2.13 2.21 0.013 0.450 100 Yr Results J-loss Coeff N-value Pipe Velocity Down (ft/s) Velocity Up (ft/s) Velocity Avg (ft/s) EGL Down (ft) EGL Up (ft) HGL Down (ft) HGL Up (ft) Invert Down (ft) Invert Up (ft) Line Slope (ft/ft) Line Length (ft) Line Size (in) Capacity (Design) (cfs) Flow (cfs) Label CO-2 7.30 8.60 18.0 108.5 0.004 4,917.14 4,916.71 4,918.20 4,917.76 4,918.66 4,918.23 5.46 5.46 5.54 0.010 0.700 CO-3 14.30 17.82 21.0 92.2 0.007 4,915.81 4,915.12 4,917.21 4,916.32 4,917.96 4,917.35 8.24 6.91 8.11 0.010 0.500 CO-4 1.20 3.26 12.0 50.4 0.005 4,919.60 4,919.35 4,920.06 4,920.00 4,920.24 4,920.08 3.84 3.38 2.20 0.010 1.500 CO-5 2.30 3.27 12.0 66.3 0.005 4,919.15 4,918.82 4,919.82 4,919.77 4,920.08 4,919.91 4.50 4.10 2.98 0.010 0.700 CO-6 3.20 3.23 12.0 22.6 0.005 4,918.62 4,918.51 4,919.43 4,919.28 4,919.77 4,919.66 4.69 4.72 4.95 0.010 1.000 CO-7 0.25 3.27 12.0 22.1 0.005 4,919.23 4,919.12 4,919.78 4,919.78 4,919.78 4,919.78 2.46 0.57 0.46 0.010 1.500 CO-8 0.50 3.21 12.0 20.9 0.005 4,918.92 4,918.82 4,919.77 4,919.77 4,919.78 4,919.78 2.97 0.70 0.65 0.010 0.700 CO-9 0.25 3.23 12.0 30.9 0.005 4,919.29 4,919.14 4,919.78 4,919.78 4,919.78 4,919.78 2.44 0.66 0.47 0.010 1.500 CO-10 0.50 3.27 12.0 24.1 0.005 4,918.94 4,918.82 4,919.77 4,919.77 4,919.78 4,919.78 3.01 0.72 0.65 0.010 0.700 CO-11 1.90 3.26 12.0 28.3 0.005 4,916.72 4,916.58 4,917.62 4,917.58 4,917.72 4,917.67 4.30 2.56 2.42 0.010 1.500 CO-12 3.00 3.18 12.0 16.9 0.005 4,916.58 4,916.50 4,917.35 4,917.24 4,917.68 4,917.60 4.61 4.62 4.80 0.010 0.700 CO-13 6.90 5.87 15.0 12.3 0.005 4,916.50 4,916.44 4,917.64 4,917.49 4,918.18 4,918.10 5.62 5.89 6.25 0.010 0.500 CO-14 0.50 8.77 18.0 164.9 0.007 4,913.40 4,912.25 4,913.66 4,912.53 4,913.75 4,912.60 2.69 2.41 2.24 0.013 0.500 CO-15 0.50 8.84 18.0 317.6 0.007 4,912.25 4,910.00 4,912.51 4,910.28 4,912.60 4,910.35 2.70 2.41 2.24 0.013 0.150 CO-16 0.50 8.84 18.0 301.8 0.007 4,910.00 4,907.86 4,910.26 4,908.10 4,910.35 4,908.22 2.70 2.41 2.70 0.013 0.150 CO-17 0.50 9.51 18.0 11.0 0.008 4,907.66 4,907.57 4,907.92 4,907.80 4,908.01 4,907.93 2.85 2.41 2.85 0.013 0.450 CO-18 0.50 74.94 42.0 9.0 0.006 4,905.57 4,905.52 4,905.78 4,905.72 4,905.85 4,905.80 2.21 2.13 2.21 0.013 0.450 Subdivision: 0 Project Name: Windsong Location: Fort Collins Project No.: 39727.00 Calculated By: BAB Checked By: 0 Date: 4/20/16 FES 1-3 FES 11-1 FES 1-1 FES 6-1 FES 4-1 FES 10-1 Q100 (cfs) 7.3 0.9 14.3 1.7 6.9 3.7 Flows are the greater of proposed vs. future D or H (in) 18 12 21 12 15 12 W (ft) Slope (%) 0.40 0.50 0.75 0.50 0.50 0.50 Yn (in) 4.13 2.88 6.48 3.41 5.64 4.74 Yt (ft) Unknown Unknown Unknown Unknown Unknown Unknown If "Unknown" Yt/D=0.4 Yt/D, Yt/H 0.40 0.40 0.40 0.40 0.40 0.40 Per Chapter 9, Section 3.2.3 Supercritical (yes/no) no no no no no no Da, Ha (in) * Da=0.5(D+Yn), Ha=0.5(H+Yn) d50 (in), Required 0.34 0.06 0.56 0.12 0.38 0.26 Required Riprap Size L L L L L L Fig. 9-38 or Fig. 9-36 Use Riprap Size L L L L L L d50 (in) 9 9 9 9 9 9 Table MD-7 Expansion Factor, 1/(2 tanT) 4.50 4.50 4.50 4.50 4.50 4.50 Fig. 9-35 OR 9-36 T 0.11 0.11 0.11 0.11 0.11 0.11 Erosive Soils? No No No No No No At 0.95 0.11 1.86 0.23 0.90 0.48 At=Q/V Lp 0.3 -3.2 4.1 -1.9 2.5 0.9 L=(1/(2 tan q))(At/Yt - D) Min Length (ft) 4.5 3.0 5.3 3.0 3.8 3.0 Min L=3D or 3H Max Length (ft) 15.0 10.0 17.5 10.0 12.5 10.0 Max L=10D or 10H Min Bottom Width, T (ft) 3.1 1.3 4.4 1.6 3.0 2.2 T=2*(Lp*tanT)+W Design Length (ft) 4.5 3.0 5.3 3.0 3.8 3.0 Design Width (ft) 3.1 1.3 4.4 1.6 3.0 2.2 Riprap Depth (in) 18 18 18 18 18 18 Depth=2(d50) Type II Base Depth (in) 6 6 6 6 6 6 *Not used if Soil Riprap Cutoff Wall No No No No No No Cutoff Wall Depth (ft) Depth of Riprap and Base Cutoff Wall Width (ft) Note: No Type II Base to be used if Soil Riprap is specified within the plans * For use when the flow in the culvert is supercritical (and less than full). STORM DRAIN SYSTEM PIPE OUTFALL RIPRAP SIZING CALCULATIONS X:\3970000.all\3972700\Excel\Drainage\3972700 Drainage_Calcs_v2.0.xlsm Page 1 of 2 4/19/2016 Windsong at Rock Creek Final Drainage Report APPENDIX D – WATER QUALITY/DETENTION CALCULATIONS Subdivision: 0 Project Name: Windsong Location: Fort Collins Project No.: 39727.00 Calculated By: BAB Checked By: 0 Date: 4/20/16 Basin Area (ac) % Imp. A1 0.39 64.6% A2 0.50 71.1% A3 0.11 67.0% A4 0.18 59.1% A5 0.24 90.0% A6 0.24 90.0% A7 0.10 90.0% A8 0.19 6.8% A9 0.09 72.6% A10 0.02 39.2% A11 0.12 84.1% A12 0.29 47.2% B1 0.04 13.7% B2 0.21 12.8% B3 0.08 65.1% B4 0.14 75.5% B5 0.02 20.2% C6 0.20 94.1% Total 3.16 63.9% WQCV Drain Time (hr): 40 Coefficient, a (Table 3-2): 1.0 WQCV (in): 0.25 WQCV (ac-ft): 0.07 Detention Pond Tributary Areas WQ Detention/ Basins Treated by LID X:\3970000.all\3972700\Excel\Drainage\3972700 Drainage_Calcs_v2.0.xlsm Page 1 of 1 4/19/2016 Project: Basin ID: Design Information (Input): Design Information (Input): Catchment Drainage Imperviousness Ia = 63.90 percent Catchment Drainage Imperviousness I a = 63.90 percent Catchment Drainage Area A = 3.160 acres Catchment Drainage Area A = 3.160 acres Predevelopment NRCS Soil Group Type = C A, B, C, or D Predevelopment NRCS Soil Group Type = C A, B, C, or D Return Period for Detention Control T = 2 years (2, 5, 10, 25, 50, or 100) Return Period for Detention Control T = 100 years (2, 5, 10, 25, 50, or 100) Time of Concentration of Watershed Tc = 4 minutes Time of Concentration of Watershed Tc = 4 minutes Allowable Unit Release Rate q = 0.158 cfs/acre Allowable Unit Release Rate q = 0.158 cfs/acre One-hour Precipitation P1 = 0.82 inches One-hour Precipitation P 1 = 2.86 inches Design Rainfall IDF Formula i = C1* P1 /(C2+Tc )^C3 Design Rainfall IDF Formula i = C1 * P1/(C2 +Tc)^C3 Coefficient One C1 = 28.50 Coefficient One C 1 = 28.50 Coefficient Two C2 = 10 Coefficient Two C 2 = 10 Coefficient Three C3 = 0.786 Coefficient Three C 3 = 0.786 Determination of Average Outflow from the Basin (Calculated): Determination of Average Outflow from the Basin (Calculated): Runoff Coefficient C = 0.44 Runoff Coefficient C = 0.65 Inflow Peak Runoff Qp-in = 4.19 cfs Inflow Peak Runoff Qp-in = 21.60 cfs Allowable Peak Outflow Rate Qp-out = 0.50 cfs Allowable Peak Outflow Rate Qp-out = 0.50 cfs Mod. FAA Minor Storage Volume = 3,300 cubic feet Mod. FAA Major Storage Volume = 28,633 cubic feet Mod. FAA Minor Storage Volume = 0.076 acre-ft Mod. FAA Major Storage Volume = 0.657 acre-ft 5 <- Enter Rainfall Duration Incremental Increase Value Here (e.g. 5 for 5-Minutes) Rainfall Rainfall Inflow Adjustment Average Outflow Storage Rainfall Rainfall Inflow Adjustment Average Outflow Storage Duration Intensity Volume Factor Outflow Volume Volume Duration Intensity Volume Factor Outflow Volume Volume minutes inches / hr acre-feet "m" cfs acre-feet acre-feet minutes inches / hr acre-feet "m" cfs acre-feet acre-feet (input) (output) (output) (output) (output) (output) (output) (input) (output) (output) (output) (output) (output) (output) 0 0.00 0.000 0.00 0.00 0.000 0.000 0 0.00 0.000 0.00 0.00 0.000 0.000 5 2.78 0.027 0.85 0.43 0.003 0.024 5 9.70 0.137 0.85 0.43 0.003 0.134 10 2.22 0.042 0.68 0.34 0.005 0.038 10 7.74 0.219 0.68 0.34 0.005 0.214 15 1.86 0.053 0.62 0.31 0.006 0.047 15 6.49 0.276 0.62 0.31 0.006 0.269 20 1.61 0.062 0.59 0.29 0.008 0.054 20 5.63 0.318 0.59 0.29 0.008 0.310 25 1.43 0.068 0.57 0.28 0.010 0.059 25 4.98 0.353 0.57 0.28 0.010 0.343 30 1.29 0.074 0.56 0.28 0.012 0.062 30 4.49 0.381 0.56 0.28 0.012 0.369 35 1.17 0.079 0.55 0.27 0.013 0.065 35 4.09 0.405 0.55 0.27 0.013 0.392 40 1.08 0.083 0.54 0.27 0.015 0.068 40 3.77 0.426 0.54 0.27 0.015 0.411 45 1.00 0.086 0.54 0.27 0.017 0.070 45 3.49 0.445 0.54 0.27 0.017 0.428 50 0.94 0.090 0.54 0.27 0.018 0.071 50 3.26 0.462 0.54 0.27 0.018 0.443 55 0.88 0.093 0.53 0.27 0.020 0.072 55 3.06 0.477 0.53 0.27 0.020 0.457 60 0.83 0.095 0.53 0.26 0.022 0.073 60 2.89 0.491 0.53 0.26 0.022 0.469 65 0.78 0.098 0.53 0.26 0.024 0.074 65 2.74 0.503 0.53 0.26 0.024 0.480 70 0.75 0.100 0.53 0.26 0.025 0.075 70 2.60 0.515 0.53 0.26 0.025 0.490 75 0.71 0.102 0.52 0.26 0.027 0.075 75 2.48 0.527 0.52 0.26 0.027 0.500 80 0.68 0.104 0.52 0.26 0.029 0.075 80 2.37 0.537 0.52 0.26 0.029 0.508 85 0.65 0.106 0.52 0.26 0.030 0.076 85 2.27 0.547 0.52 0.26 0.030 0.516 90 0.63 0.108 0.52 0.26 0.032 0.076 90 2.18 0.556 0.52 0.26 0.032 0.524 95 0.60 0.110 0.52 0.26 0.034 0.076 95 2.10 0.565 0.52 0.26 0.034 0.531 100 0.58 0.111 0.52 0.26 0.036 0.076 100 2.03 0.573 0.52 0.26 0.036 0.538 105 0.56 0.113 0.52 0.26 0.037 0.075 105 1.96 0.581 0.52 0.26 0.037 0.544 110 0.54 0.114 0.52 0.26 0.039 0.075 110 1.89 0.589 0.52 0.26 0.039 0.550 115 0.53 0.116 0.52 0.26 0.041 0.075 115 1.83 0.596 0.52 0.26 0.041 0.555 120 0.51 0.117 0.51 0.26 0.042 0.075 120 1.78 0.603 0.51 0.26 0.042 0.561 125 0.49 0.118 0.51 0.26 0.044 0.074 125 1.72 0.610 0.51 0.26 0.044 0.566 Project: Basin ID: DETENTION VOLUME BY THE MODIFIED FAA METHOD Windsong at Rock Creek Pond A/B UDFCD DETENTION BASIN VOLUME ESTIMATING WORKBOOK Version 2.35, Released January 2015 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0 50 100 150 200 250 300 350 Volume (acre-feet) Duration (Minutes) Inflow and Outflow Volumes vs. Rainfall Duration Minor Storm Inflow Volume Minor Storm Outflow Volume Minor Storm Storage Volume Major Storm Inflow Volume Major Storm Outflow Volume Major Storm Storage Volume UD-Detention - Pond A.xls, Modified FAA 2/16/2016, 2:40 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 = 4,920.55 feet Pipe/Vertical Orifice Entrance Invert Elevation Elev: Invert = 4,915.00 feet Required Peak Flow through Orifice at Design Depth Q = 0.50 cfs Pipe/Vertical Orifice Diameter (inches) Dia = 18.0 inches Orifice Coefficient Co = 0.63 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 = 19.4 cfs Percent of Design Flow = 3890% Calculation of Orifice Flow Condition Half Central Angle (0<Theta<3.1416) Theta = 0.49 rad Flow area Ao = 0.04 sq ft Top width of Orifice (inches) To = 8.50 inches Height from Invert of Orifice to Bottom of Plate (feet) Yo = 0.09 feet Elevation of Bottom of Plate Elev Plate Bottom Edge = 4,915.09 feet Resultant Peak Flow Through Orifice at Design Depth Qo = 0.5 cfs Width of Equivalent Rectangular Vertical Orifice Equivalent Width = 0.44 feet Centroid Elevation of Equivalent Rectangular Vertical Orifice Equiv. Centroid El. = 4,915.05 feet Windsong at Rock Creek Pond A RESTRICTOR PLATE SIZING FOR CIRCULAR VERTICAL ORIFICES UD-Detention - Pond A.xls, Restrictor Plate 4/19/2016, 12:21 PM Project: Basin ID: Design Information (Input): #1 Horiz. #2 Horiz. #1 Vert. #2 Vert. Circular Opening: Diameter in Inches Dia. = inches OR Rectangular Opening: Width in Feet W = 2.92 0.44 ft. Length (Height for Vertical) L or H = 2.92 0.09 ft. Percentage of Open Area After Trash Rack Reduction % open = 65 100 % Orifice Coefficient Co = 0.63 0.63 Weir Coefficient Cw = 3.00 Orifice Elevation (Bottom for Vertical) Eo = 4915.00 4,915.00 ft. Calculation of Collection Capacity: Net Opening Area (after Trash Rack Reduction) Ao = 5.54 0.04 sq. ft. OPTIONAL: User-Overide Net Opening Area Ao = sq. ft. Perimeter as Weir Length Lw = 9.64 ft. OPTIONAL: User-Overide Weir Length Lw = ft. Top Elevation of Vertical Orifice Opening, Top = 4915.09 ft. Center Elevation of Vertical Orifice Opening, Cen = 4915.05 ft. Horizontal Orifices Vertical Orifices Labels Water WQCV #1 Horiz. #1 Horiz. #2 Horiz. #2 Horiz. #1 Vert. #2 Vert. Total Target Volumes for WQCV, Minor, Surface Plate/Riser Weir Orifice Weir Orifice Collection Collection Collection for WQCV, Minor, & Major Storage Elevation Flow Flow Flow Flow Flow Capacity Capacity Capacity & Major Storage W.S. Elevations ft cfs cfs cfs cfs cfs cfs cfs cfs Volumes (input) (linked) (User-linked) (output) (output) (output) (output) (output) (output) (output) (link for goal seek) 4915.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 4915.50 0.00 10.22 19.66 0.00 0.00 0.14 0.00 0.14 4916.00 0.00 28.91 27.80 0.00 0.00 0.20 0.00 0.20 4916.50 0.00 53.11 34.04 0.00 0.00 0.24 0.00 0.24 4917.01 0.00 82.38 39.41 0.00 0.00 0.28 0.00 0.28 2 YR 4917.07 0.00 86.09 39.99 0.00 0.00 0.29 0.00 0.29 4917.50 0.00 114.27 43.95 0.00 0.00 0.31 0.00 0.31 4918.00 0.00 150.21 48.15 0.00 0.00 0.34 0.00 0.34 4918.50 0.01 189.29 52.00 0.00 0.00 0.37 0.00 0.37 4919.00 0.02 231.26 55.59 0.00 0.00 0.40 0.00 0.40 4919.50 0.04 275.95 58.97 0.00 0.00 0.42 0.00 0.42 4920.00 0.06 323.20 62.16 0.00 0.00 0.45 0.00 0.45 100 YR 4920.54 0.07 376.95 65.43 0.00 0.00 0.47 0.00 0.47 4921.00 0.08 424.86 68.09 0.00 0.00 0.49 0.00 0.49 #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A Project: Basin ID: Windsong at Rock Creek Pond A/B STAGE-DISCHARGE SIZING OF THE WEIRS AND ORIFICES (INLET CONTROL) 4915.27 4916.27 4917.27 4918.27 4919.27 4920.27 4921.27 4922.27 0 0.1 0.2 0.3 0.4 0.5 0.6 Stage (feet, elev.) Discharge (cfs) STAGE-DISCHARGE CURVE FOR THE OUTLET STRUCTURE UD-Detention - Pond A.xls, Outlet 4/19/2016, 12:44 PM Project: Basin ID: 75.96 4.00000 Design Information (input): Bottom Length of Weir L = 19.50 feet Angle of Side Slope Weir Angle = 75.96 degrees Elev. for Weir Crest EL. Crest = 4,920.55 feet Coef. for Rectangular Weir Cw = 3.33 Coef. for Trapezoidal Weir Ct = 2.60 Calculation of Spillway Capacity (output): Water Rect. Triangle Total Total Surface Weir Weir Spillway Pond Elevation Flowrate Flowrate Release Release ft. cfs cfs cfs cfs (linked) (output) (output) (output) (output) 4915.00 0.00 0.00 0.00 0.00 4915.50 0.00 0.00 0.00 0.00 4916.00 0.00 0.00 0.00 0.00 4916.50 0.00 0.00 0.00 0.00 4917.01 0.00 0.00 0.00 0.00 4917.07 0.00 0.00 0.00 0.00 4917.50 0.00 0.00 0.00 0.00 4918.00 0.00 0.00 0.00 0.00 4918.50 0.00 0.00 0.00 0.00 4919.00 0.00 0.00 0.00 0.00 4919.50 0.00 0.00 0.00 0.00 4920.00 0.00 0.00 0.00 0.00 4920.54 0.00 0.00 0.00 0.00 4921.00 19.60 1.41 21.01 21.01 #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A #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-DISCHARGE SIZING OF THE SPILLWAY Windsong at Rock Creek Pond A 0 0.2 0.4 0.6 0.8 1 4915.27 4916.27 4917.27 4918.27 4919.27 4920.27 4921.27 4922.27 0 5 10 15 20 25 Storage (Acre-Feet) Stage (feet, elev.) Pond Discharge (cfs) STAGE-STORAGE-DISCHARGE CURVES FOR THE POND TOTAL DISCHARGE SPILLWAY DISCHARGE POND STORAGE UD-Detention - Pond A.xls, Spillway 4/19/2016, 12:22 PM Subdivision: 0 Project Name: Windsong Location: Fort Collins Project No.: 39727.00 By: BAB Volume=1/3 x Depth x (A+B+(A*B)^0.5) Checked By: 0 A - Upper Surface Date: 4/20/16 B - Lower Surface Pond A & B Volume Stage Stage Elevation Stage Surface Area Stage Volume Cumulative Volume Cumulative Volume (square feet) (cubic feet) (cubic feet) (acre feet) 0.00 4915.00 7 0 0 0.00 1.00 4916.00 1,671 595 595 0.01 2.00 4917.00 3,291 2,435 3,030 0.07 3.00 4918.00 5,523 4,359 7,389 0.17 4.00 4919.00 7,987 6,717 14,106 0.32 5.00 4920.00 9,453 8,710 22,816 0.52 6.00 4921.00 11,811 10,610 33,426 0.77 Volume (acre feet) Volume Water Surface Elevation Water Quality 0.07 4917.01 2-Year Detention 0.076 4917.07 100-Year Detention 0.657 4920.55 POND VOLUME CALCULATIONS X:\3970000.all\3972700\Excel\Drainage\3972700 Drainage_Calcs_v2.0.xlsm Page 1 of 2 4/19/2016 Subdivision: 0 Project Name: Windsong Location: Fort Collins Project No. 39727.00 By: BAB Checked By: 0 Date: 4/20/16 POND VOLUME CALCULATIONS 4914.00 4915.00 4916.00 4917.00 4918.00 4919.00 4920.00 4921.00 4922.00 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 Elevation (ft) Pond Volume (ac-ft) Pond Stage-Storage X:\3970000.all\3972700\Excel\Drainage\3972700 Drainage_Calcs_v2.0.xlsm Page 2 of 2 4/19/2016 Stormwater Facility Name: Facility Location & Jurisdiction: User (Input) Watershed Characteristics User Defined User Defined User Defined User Defined Watershed Slope = 0.005 ft/ft Stage [ft] Area [ft^2] Stage [ft] Discharge [cfs] Watershed Length-to-Width Ratio = 1.00 L:W 0.00 7 0.00 0.00 Watershed Area = 3.16 acres 1.00 1,671 1.00 0.00 Watershed Imperviousness = 63.9% percent 2.00 3,291 2.00 0.00 Percentage Hydrologic Soil Group A = 0.0% percent 3.00 5,523 3.00 0.34 Percentage Hydrologic Soil Group B = 0.0% percent 4.00 7,987 4.00 0.40 Percentage Hydrologic Soil Groups C/D = 100.0% percent 5.00 9,453 5.00 0.45 6.00 11,811 6.00 0.50 User Input 17 User Input: Detention Basin Characteristics WQCV Design Drain Time = 40.00 hours After completing and printing this worksheet to a pdf, go to: https://maperture.digitaldataservices.com/gvh/?viewer=cswdif create a new stormwater facility, and attach the pdf of this worksheet to that record. Routed Hydrograph Results Design Storm Return Period = WQCV 2 Year 5 Year 10 Year 50 Year 100 Year One-Hour Rainfall Depth = 0.53 0.82 1.40 2.86 in Calculated Runoff Volume = 0.065 0.133 0.000 0.279 0.000 0.671 acre-ft OPTIONAL Override Runoff Volume = acre-ft Inflow Hydrograph Volume = 0.064 0.133 #N/A 0.278 #N/A 0.670 acre-ft Time to Drain 97% of Inflow Volume = >119 >119 #N/A >119 #N/A >119 hours Time to Drain 99% of Inflow Volume = >119 >119 #N/A >119 #N/A >119 hours Maximum Ponding Depth = 1.84 2.48 #N/A 3.45 #N/A 5.34 ft Maximum Ponded Area = 0.069 0.100 #N/A 0.152 #N/A 0.235 acres Maximum Volume Stored = 0.064 0.118 #N/A 0.239 #N/A 0.608 acre-ft Stormwater Detention and Infiltration Design Data Sheet Windsong at Rock Creek Pond A & B Location for 1-hr Rainfall Depths (use dropdown): Workbook Protected Worksheet Protected 3972700 SDI_Design_Data_v1.01 Pond A&B.xlsm, Design Data 2/22/2016, 9:28 AM Doing_Clear_Formatting Yes = CountA= 1 0 1 2 3 #N/A #N/A 0 1 2 3 #N/A #N/A Check Data Set 0 Check Data Set 0 Stormwater Detention and Infiltration Design Data Sheet Area Discharge 0 2 4 6 8 10 12 14 16 0.1 1 10 FLOW [cfs] TIME [hr] 100YR IN 100YR OUT 50YR IN 50YR OUT 10YR IN 10YR OUT 5YR IN 5YR OUT 2YR IN 2YR OUT WQCV IN WQCV OUT 0 1 2 3 4 5 6 0.1 1 10 100 PONDING DEPTH [ft] DRAIN TIME [hr] 100YR 50YR 10YR 5YR 2YR WQCV 3972700 SDI_Design_Data_v1.01 Pond A&B.xlsm, Design Data 2/22/2016, 9:28 AM Sheet 1 of 2 Designer: Company: Date: Project: Location: 1. Basin Storage Volume A) Effective Imperviousness of Tributary Area, Ia Ia = 69.2 % (100% if all paved and roofed areas upstream of sand filter) B) Tributary Area's Imperviousness Ratio (i = Ia/100) i = 0.692 C) Water Quality Capture Volume (WQCV) Based on 12-hour Drain Time WQCV = 0.24 watershed inches WQCV= 0.9 * (0.91* i3 - 1.19 * i2 + 0.78 * i) D) Contributing Watershed Area (including sand filter area) Area = 79,886 sq ft E) Water Quality Capture Volume (WQCV) Design Volume VWQCV = 1,626 cu ft VWQCV = WQCV / 12 * Area F) For Watersheds Outside of the Denver Region, Depth of d6 = 0.82 in Average Runoff Producing Storm G) For Watersheds Outside of the Denver Region, VWQCV OTHER = 3,102 cu ft Water Quality Capture Volume (WQCV) Design Volume H) User Input of Water Quality Capture Volume (WQCV) Design Volume VWQCV USER = cu ft (Only if a different WQCV Design Volume is desired) 2. Basin Geometry A) WQCV Depth DWQCV = 2.52 ft B) Sand Filter Side Slopes (Horizontal distance per unit vertical, Z = 4.00 ft / ft 4:1 or flatter preferred). Use "0" if sand filter has vertical walls. C) Mimimum Filter Area (Flat Surface Area) AMin = 689 sq ft D) Actual Filter Area AActual = 800 sq ft E) Volume Provided VT = 8043 cu ft 3. Filter Material 4. Underdrain System A) Are underdrains provided? B) Underdrain system orifice diameter for 12 hour drain time i) Distance From Lowest Elevation of the Storage y = 2.0 ft Volume to the Center of the Orifice ii) Volume to Drain in 12 Hours Vol12 = 3,102 cu ft iii) Orifice Diameter, 3/8" Minimum DO = 1 - 1 / 4 in Windsong Fort Collins Pond C Design Procedure Form: Sand Filter (SF) JR Engineering April 19, 2016 Choose One Choose One 18" CDOT Class C Filter Material Other (Explain): YES NO 3972700 UD-BMP_v3.03 Pond C Sand Filter.xlsm, SF 4/19/2016, 12:11 PM Sheet 2 of 2 Designer: Company: Date: Project: Location: 5. Impermeable Geomembrane Liner and Geotextile Separator Fabric A) Is an impermeable liner provided due to proximity of structures or groundwater contamination? 6-7. Inlet / Outlet Works A) Describe the type of energy dissipation at inlet points and means of conveying flows in excess of the WQCV through the outlet Notes: Design Procedure Form: Sand Filter (SF) JR Engineering April 19, 2016 Windsong Fort Collins Pond C Choose One YES NO 3972700 UD-BMP_v3.03 Pond C Sand Filter.xlsm, SF 4/19/2016, 12:11 PM Sheet 1 of 2 Designer: Company: Date: Project: Location: 1. Basin Storage Volume A) Effective Imperviousness of Tributary Area, Ia Ia = 54.1 % (100% if all paved and roofed areas upstream of sand filter) B) Tributary Area's Imperviousness Ratio (i = Ia/100) i = 0.541 C) Water Quality Capture Volume (WQCV) Based on 12-hour Drain Time WQCV = 0.20 watershed inches WQCV= 0.9 * (0.91* i3 - 1.19 * i2 + 0.78 * i) D) Contributing Watershed Area (including sand filter area) Area = 33,412 sq ft E) Water Quality Capture Volume (WQCV) Design Volume VWQCV = 546 cu ft VWQCV = WQCV / 12 * Area F) For Watersheds Outside of the Denver Region, Depth of d6 = 0.82 in Average Runoff Producing Storm G) For Watersheds Outside of the Denver Region, VWQCV OTHER = 1,041 cu ft Water Quality Capture Volume (WQCV) Design Volume H) User Input of Water Quality Capture Volume (WQCV) Design Volume VWQCV USER = cu ft (Only if a different WQCV Design Volume is desired) 2. Basin Geometry A) WQCV Depth DWQCV = 0.47 ft B) Sand Filter Side Slopes (Horizontal distance per unit vertical, Z = 4.00 ft / ft 4:1 or flatter preferred). Use "0" if sand filter has vertical walls. C) Mimimum Filter Area (Flat Surface Area) AMin = 231 sq ft D) Actual Filter Area AActual = 1050 sq ft E) Volume Provided VT = 10399 cu ft 3. Filter Material 4. Underdrain System A) Are underdrains provided? B) Underdrain system orifice diameter for 12 hour drain time i) Distance From Lowest Elevation of the Storage y = 2.0 ft Volume to the Center of the Orifice ii) Volume to Drain in 12 Hours Vol12 = 1,041 cu ft iii) Orifice Diameter, 3/8" Minimum DO = 11 / 16 in Windsong Fort Collins Pond B Design Procedure Form: Sand Filter (SF) JR Engineering April 19, 2016 Choose One Choose One 18" CDOT Class C Filter Material Other (Explain): YES NO 3972700 UD-BMP_v3.03 Pond B Sand Filter.xlsm, SF 4/19/2016, 12:09 PM Sheet 2 of 2 Designer: Company: Date: Project: Location: 5. Impermeable Geomembrane Liner and Geotextile Separator Fabric A) Is an impermeable liner provided due to proximity of structures or groundwater contamination? 6-7. Inlet / Outlet Works A) Describe the type of energy dissipation at inlet points and means of conveying flows in excess of the WQCV through the outlet Notes: Design Procedure Form: Sand Filter (SF) JR Engineering April 19, 2016 Windsong Fort Collins Pond B Choose One YES NO 3972700 UD-BMP_v3.03 Pond B Sand Filter.xlsm, SF 4/19/2016, 12:09 PM Windsong at Rock Creek Final Drainage Report APPENDIX E – MAPS City of Fort Collins, Colorado UTILITY PLAN APPROVAL CityDate Engineer WaterDate & Wastewater Utility StormwaterDate Utility ParksDate & Recreation TrafficDate Engineer Date EnvironmentalDate Planner Date Tributary Area Percent tc Q 2 Sub-basin (acres) Impervious C2 (min) (cfs) EX1 2.99 2% 0.10 23.3 0.4 EX2 0.17 2% 0.10 14.2 0.0 EX3 0.19 2% 0.10 6.8 0.0 OF1 2.30 2% 0.10 23.7 0.3 Existing BASIN SUMMARY TABLE City of Fort Collins, Colorado UTILITY PLAN APPROVAL CityDate Engineer WaterDate & Wastewater Utility StormwaterDate Utility ParksDate & Recreation TrafficDate Engineer Date EnvironmentalDate Planner Date Tributary Area Percent tc Q5 Q100 Sub-basin (acres) Impervious C2 C100 (min) (cfs) (cfs) A1 0.39 65% 0.66 0.83 5.0 0.7 3.1 A2 0.50 71% 0.72 0.90 5.5 1.0 4.2 A3 0.11 67% 0.75 0.93 5.0 0.2 1.0 A4 0.18 59% 0.64 0.80 5.0 0.3 1.4 A5 0.24 90% 0.95 1.00 5.0 0.6 2.3 A6 0.24 90% 0.95 1.00 5.0 0.6 2.3 A7 0.10 90% 0.95 1.00 5.0 0.3 1.0 A8 0.19 7% 0.12 0.15 5.0 0.1 0.3 A9 0.09 73% 0.77 0.96 5.0 0.2 0.8 A10 0.02 39% 0.42 0.53 5.0 0.0 0.1 A11 0.12 84% 0.85 1.00 5.0 0.3 1.1 A12 0.29 47% 0.49 0.61 5.0 0.4 1.7 B1 0.04 14% 0.19 0.23 5.0 0.0 0.1 B2 0.21 13% 0.18 0.22 7.2 0.1 0.4 B3 0.08 65% 0.70 0.88 5.0 0.2 0.7 B4 0.14 75% 0.78 0.97 5.0 0.3 1.4 B5 0.02 20% 0.24 0.30 7.2 0.0 0.1 C1 0.06 25% 0.30 0.37 5.0 0.0 0.2 C2 0.13 26% 0.31 0.39 5.3 0.1 0.5 C3 0.10 33% 0.38 0.48 5.0 0.1 0.4 C4 0.09 22% 0.27 0.33 5.0 0.1 0.3 C5 0.05 80% 0.82 1.00 5.0 0.1 0.4 C6 0.20 94% 0.92 1.00 5.0 0.5 1.9 BASIN SUMMARY TABLE Top of Pond Volume WS Release Volume WS WS Release Elevation (acres) (ft) (cfs) (acres) (ft) (ft) (cfs) (ft) Pond A 0.452 - 0.45 4920.55 0.5 - - 4920.55 21.7 4921.55 Pond B 0.205 0.023 0.205 4920.55 4.5 0.023 4918.47 - - 4921.00 Pond C - 0.078 - - 14.3 0.078 4919.02 - - 4920.00 Total 0.657 0.101 - - - - - - - - Detention Pond Summary Table Storage Volume Required (acre-ft) WQCV Required (acre-ft) 100-yr Emergency Overflow Pond WQCV DETENTION POND B DETENTION POND A POND C City of Fort Collins, Colorado UTILITY PLAN APPROVAL CityDate Engineer WaterDate & Wastewater Utility StormwaterDate Utility ParksDate & Recreation TrafficDate Engineer Date EnvironmentalDate Planner Date WINDSONG AT ROCK CREEK IMPERVIOUS AREA TREATMENT PLAN City of Fort Collins, Colorado UTILITY PLAN APPROVAL CityDate Engineer WaterDate & Wastewater Utility StormwaterDate Utility ParksDate & Recreation TrafficDate Engineer Date EnvironmentalDate Planner Date New Impervious Area 90,342 sq. ft. Required Minimum Impervious Area to be Treated 45,171 sq. ft. (=50% of new impervious area) Area of Paver Section #1 7,322 sq. ft. Run-on area for Paver Section #1 (1.0:1) 8,534 sq. ft. Area of Sand Filter Pond C 7,234 sq. ft. Impervious Area Treated by LID Treatment Method #2- Sand Filter Pond C (8.0:1) 58,174 sq. ft. Area of Sand Filter Pond B 5,813 sq. ft. Impervious Area Treated by LID Treatment Method #3- Sand Filter Pond B (3.0:1) 17,402 sq. ft. Total Impervious Area Treated 84,110 sq. ft. Actual % of New Impervious Area Treated 93.1% New Pavement Area 33,178 sq. ft. Required Minimum Area of Porous Pavement (=25% of new pavement area) 8,295 sq. ft. Area of Paver Section #1 7,322 sq. ft. Total Porous Pavement Area 7,322 sq. ft. Actual % of Porous Pavement Provided 22.1% 50% On-Site Treatment by LID Requirement Porous Pavement Requirement STAGE-DISCHARGE SIZING OF THE SPILLWAY Windsong at Rock Creek Pond A UD-Detention - Pond A.xls, Spillway 4/19/2016, 12:22 PM #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A #N/A #N/A #N/A #N/A #N/A #N/A 0.00 #N/A Routing 3: Single Stage - Water flows through WQCV plate and #1 horizontal opening into #1 vertical opening. This flow will be applied to culvert sheet (#2 vertical & horizontal openings is not used). STAGE-DISCHARGE SIZING OF THE WEIRS AND ORIFICES (INLET CONTROL) Windsong at Rock Creek Pond A/B Current Routing Order is #3 W.S. EL. WQ W.S. EL. Minor W.S. EL. Major WQ H1 H2 V1 V2 Routing Order #1 (Standard) V1 W.S. EL. WQ W.S. EL. Design Storm WQ H1 Routing Order #3 (Single Stage) Routing Order #4 V2 V1 H1 WQ W.S. EL. Major W.S. EL. Minor W.S. EL. WQ W.S. EL. Emergency Spillway Emergency Overflow into Pipe- H2 V2 H1 WQ W.S. EL. Major W.S. EL. Minor W.S. EL. WQ V1 Routing Order #2 UD-Detention - Pond A.xls, Outlet 4/19/2016, 12:44 PM 130 0.48 0.120 0.51 0.26 0.046 0.074 130 1.68 0.617 0.51 0.26 0.046 0.571 135 0.47 0.121 0.51 0.26 0.048 0.073 135 1.63 0.623 0.51 0.26 0.048 0.575 140 0.46 0.122 0.51 0.26 0.049 0.073 140 1.59 0.629 0.51 0.26 0.049 0.580 145 0.44 0.123 0.51 0.26 0.051 0.072 145 1.55 0.635 0.51 0.26 0.051 0.584 150 0.43 0.124 0.51 0.26 0.053 0.072 150 1.51 0.641 0.51 0.26 0.053 0.588 155 0.42 0.125 0.51 0.26 0.055 0.071 155 1.47 0.646 0.51 0.26 0.055 0.592 160 0.41 0.126 0.51 0.26 0.056 0.070 160 1.44 0.651 0.51 0.26 0.056 0.595 165 0.40 0.127 0.51 0.25 0.058 0.069 165 1.41 0.657 0.51 0.25 0.058 0.599 170 0.39 0.128 0.51 0.25 0.060 0.069 170 1.38 0.662 0.51 0.25 0.060 0.602 175 0.39 0.129 0.51 0.25 0.061 0.068 175 1.35 0.667 0.51 0.25 0.061 0.605 180 0.38 0.130 0.51 0.25 0.063 0.067 180 1.32 0.672 0.51 0.25 0.063 0.608 185 0.37 0.131 0.51 0.25 0.065 0.066 185 1.29 0.676 0.51 0.25 0.065 0.611 190 0.36 0.132 0.51 0.25 0.067 0.066 190 1.27 0.681 0.51 0.25 0.067 0.614 195 0.36 0.133 0.51 0.25 0.068 0.065 195 1.24 0.685 0.51 0.25 0.068 0.617 200 0.35 0.134 0.51 0.25 0.070 0.064 200 1.22 0.690 0.51 0.25 0.070 0.620 205 0.34 0.135 0.51 0.25 0.072 0.063 205 1.20 0.694 0.51 0.25 0.072 0.622 210 0.34 0.135 0.51 0.25 0.073 0.062 210 1.18 0.698 0.51 0.25 0.073 0.625 215 0.33 0.136 0.51 0.25 0.075 0.061 215 1.15 0.702 0.51 0.25 0.075 0.627 220 0.33 0.137 0.51 0.25 0.077 0.060 220 1.13 0.706 0.51 0.25 0.077 0.629 225 0.32 0.138 0.51 0.25 0.079 0.059 225 1.12 0.710 0.51 0.25 0.079 0.632 230 0.31 0.139 0.51 0.25 0.080 0.058 230 1.10 0.714 0.51 0.25 0.080 0.634 235 0.31 0.139 0.51 0.25 0.082 0.057 235 1.08 0.718 0.51 0.25 0.082 0.636 240 0.30 0.140 0.51 0.25 0.084 0.056 240 1.06 0.722 0.51 0.25 0.084 0.638 245 0.30 0.141 0.51 0.25 0.085 0.055 245 1.05 0.725 0.51 0.25 0.085 0.640 250 0.30 0.141 0.51 0.25 0.087 0.054 250 1.03 0.729 0.51 0.25 0.087 0.642 255 0.29 0.142 0.51 0.25 0.089 0.053 255 1.02 0.732 0.51 0.25 0.089 0.643 260 0.29 0.143 0.51 0.25 0.091 0.052 260 1.00 0.736 0.51 0.25 0.091 0.645 265 0.28 0.143 0.51 0.25 0.092 0.051 265 0.99 0.739 0.51 0.25 0.092 0.647 270 0.28 0.144 0.51 0.25 0.094 0.050 270 0.97 0.743 0.51 0.25 0.094 0.649 275 0.27 0.145 0.51 0.25 0.096 0.049 275 0.96 0.746 0.51 0.25 0.096 0.650 280 0.27 0.145 0.51 0.25 0.097 0.048 280 0.95 0.749 0.51 0.25 0.097 0.652 285 0.27 0.146 0.51 0.25 0.099 0.047 285 0.93 0.752 0.51 0.25 0.099 0.653 290 0.26 0.147 0.51 0.25 0.101 0.046 290 0.92 0.756 0.51 0.25 0.101 0.655 295 0.26 0.147 0.51 0.25 0.103 0.045 295 0.91 0.759 0.51 0.25 0.103 0.656 300 0.26 0.148 0.51 0.25 0.104 0.043 300 0.90 0.762 0.51 0.25 0.104 0.657 Mod. FAA Minor Storage Volume (cubic ft.) = 3,300 Mod. FAA Major Storage Volume (cubic ft.) = 28,633 Mod. FAA Minor Storage Volume (acre-ft.) = 0.0758 Mod. FAA Major Storage Volume (acre-ft.) = 0.6573 DETENTION VOLUME BY THE MODIFIED FAA METHOD Windsong at Rock Creek Pond A/B Determination of MAJOR Detention Volume Using Modified FAA Method (For catchments less than 160 acres only. For larger catchments, use hydrograph routing method) (NOTE: for catchments larger than 90 acres, CUHP hydrograph and routing are recommended) UDFCD DETENTION BASIN VOLUME ESTIMATING WORKBOOK Version 2.35, Released January 2015 Determination of MINOR Detention Volume Using Modified FAA Method UD-Detention - Pond A.xls, Modified FAA 2/16/2016, 2:40 PM CO-19 1.70 3.30 12.0 11.8 0.005 4,915.69 4,915.63 4,916.24 4,916.15 4,916.47 4,916.42 4.24 3.80 4.17 0.010 1.500 CO-21 0.10 3.23 12.0 24.7 0.005 4,918.07 4,917.95 4,918.20 4,918.07 4,918.24 4,918.12 1.86 1.69 1.86 0.010 0.700 CO-22 4.50 3.57 12.0 11.8 0.006 4,917.57 4,917.50 4,920.27 4,920.16 4,920.78 4,920.67 5.73 5.73 5.73 0.010 1.500 CO-24 5.80 3.30 12.0 35.5 0.005 4,917.30 4,917.12 4,919.57 4,919.01 4,920.42 4,919.86 7.38 7.38 7.38 0.010 0.700 CO-25 5.80 3.29 12.0 43.6 0.005 4,916.92 4,916.70 4,918.59 4,917.91 4,919.44 4,918.75 7.38 7.38 7.38 0.010 0.500 CO-28 0.05 3.24 12.0 26.6 0.005 4,918.78 4,918.65 4,921.21 4,921.21 4,921.21 4,921.21 0.06 0.06 0.06 0.010 0.700 CO-29 0.08 3.25 12.0 16.3 0.005 4,918.65 4,918.57 4,921.21 4,921.21 4,921.21 4,921.21 0.10 0.10 0.10 0.010 0.500 CO-31 3.70 3.22 12.0 22.8 0.005 4,918.29 4,918.18 4,919.82 4,919.67 4,920.16 4,920.02 4.71 4.71 4.71 0.010 1.500 CO-32 3.70 3.24 12.0 16.3 0.005 4,918.18 4,918.10 4,919.43 4,919.33 4,919.78 4,919.67 4.71 4.71 4.71 0.010 0.700 CO-33 4.10 3.27 12.0 34.1 0.005 4,918.10 4,917.93 4,919.12 4,918.79 4,919.54 4,919.30 5.22 5.22 5.73 0.010 0.500 CO-34 2.30 3.26 12.0 50.4 0.005 4,919.89 4,919.64 4,922.00 4,921.87 4,922.13 4,922.00 2.93 2.93 2.93 0.010 1.500 CO-35 3.70 3.27 12.0 66.3 0.005 4,919.44 4,919.11 4,921.63 4,921.21 4,921.97 4,921.55 4.71 4.71 4.71 0.010 0.700 CO-37 0.70 3.27 12.0 78.3 0.005 4,918.74 4,918.35 4,919.33 4,919.33 4,919.36 4,919.34 3.31 1.45 0.90 0.010 1.500 CO-38 0.90 3.27 12.0 68.2 0.005 4,918.83 4,918.49 4,919.60 4,919.59 4,919.63 4,919.61 3.56 1.38 1.15 0.010 1.500 CO-39 0.90 3.24 12.0 38.9 0.005 4,918.49 4,918.30 4,918.89 4,918.66 4,919.04 4,918.85 3.53 3.09 3.53 0.010 1.000 CO-40 0.03 3.24 12.0 18.4 0.005 4,918.97 4,918.88 4,921.21 4,921.21 4,921.21 4,921.21 0.03 0.03 0.03 0.010 1.500 CO-41 0.04 3.21 12.0 20.9 0.005 4,918.88 4,918.78 4,921.21 4,921.21 4,921.21 4,921.21 0.05 0.05 0.05 0.010 0.500 CO-42 3.70 3.32 12.0 27.3 0.005 4,918.57 4,918.43 4,920.86 4,920.69 4,921.21 4,921.03 4.71 4.71 4.71 0.010 1.000 CO-43 3.70 3.28 12.0 27.9 0.005 4,918.43 4,918.29 4,920.51 4,920.34 4,920.86 4,920.68 4.71 4.71 4.71 0.010 0.500 CO-44 3.10 2.92 12.0 98.0 0.004 4,918.07 4,917.68 4,919.74 4,919.30 4,919.98 4,919.55 3.95 3.95 3.95 0.010 1.500 CO-45 3.10 2.92 12.0 135.8 0.004 4,917.68 4,917.14 4,919.13 4,918.53 4,919.38 4,918.77 3.95 3.95 3.95 0.010 0.700 27 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203- Page 1 of 1 755-1666 4/19/2016 Bentley StormCAD V8i (SELECTseries 3) 3972700StormCAD.stsw Bentley Systems, Inc. Haestad Methods Solution Center [08.11.03.84] CO-19 0.40 3.30 12.0 11.8 0.005 4,915.69 4,915.63 4,915.95 4,915.87 4,916.04 4,915.99 2.84 2.45 2.83 0.010 1.500 CO-21 0.03 3.23 12.0 24.7 0.005 4,918.07 4,917.95 4,918.14 4,918.02 4,918.16 4,918.04 1.30 1.23 1.30 0.010 0.700 CO-22 1.20 3.57 12.0 11.8 0.006 4,917.57 4,917.50 4,918.03 4,917.91 4,918.21 4,918.15 4.10 3.38 3.95 0.010 1.500 CO-24 1.40 3.30 12.0 35.5 0.005 4,917.30 4,917.12 4,917.80 4,917.57 4,918.00 4,917.83 4.03 3.56 4.03 0.010 0.700 CO-25 1.40 3.29 12.0 43.6 0.005 4,916.92 4,916.70 4,917.42 4,917.16 4,917.62 4,917.41 4.02 3.56 4.02 0.010 0.500 CO-28 0.02 3.24 12.0 26.6 0.005 4,918.78 4,918.65 4,919.12 4,919.12 4,919.12 4,919.12 1.14 0.09 0.06 0.010 0.700 CO-29 0.03 3.25 12.0 16.3 0.005 4,918.65 4,918.57 4,919.12 4,919.12 4,919.12 4,919.12 1.30 0.08 0.07 0.010 0.500 CO-31 0.90 3.22 12.0 22.8 0.005 4,918.29 4,918.18 4,918.69 4,918.68 4,918.84 4,918.76 3.51 3.09 2.28 0.010 1.500 CO-32 0.90 3.24 12.0 16.3 0.005 4,918.18 4,918.10 4,918.58 4,918.57 4,918.73 4,918.67 3.53 3.09 2.47 0.010 0.700 CO-33 0.90 3.27 12.0 34.1 0.005 4,918.10 4,917.93 4,918.50 4,918.29 4,918.65 4,918.48 3.55 3.09 3.55 0.010 0.500 CO-34 0.60 3.26 12.0 50.4 0.005 4,919.89 4,919.64 4,920.21 4,919.93 4,920.33 4,920.09 3.17 2.75 3.17 0.010 1.500 CO-35 0.90 3.27 12.0 66.3 0.005 4,919.44 4,919.11 4,919.84 4,919.47 4,919.99 4,919.67 3.55 3.09 3.55 0.010 0.700 CO-37 0.20 3.27 12.0 78.3 0.005 4,918.74 4,918.35 4,918.92 4,918.57 4,918.99 4,918.61 2.30 2.02 1.54 0.010 1.500 CO-38 0.20 3.27 12.0 68.2 0.005 4,918.83 4,918.49 4,919.37 4,919.37 4,919.38 4,919.37 2.31 0.46 0.27 0.010 1.500 CO-39 0.20 3.24 12.0 38.9 0.005 4,918.49 4,918.30 4,918.67 4,918.47 4,918.74 4,918.55 2.29 2.02 2.29 0.010 1.000 CO-40 0.01 3.24 12.0 18.4 0.005 4,918.97 4,918.88 4,919.12 4,919.12 4,919.12 4,919.12 0.93 0.14 0.07 0.010 1.500 CO-41 0.01 3.21 12.0 20.9 0.005 4,918.88 4,918.78 4,919.12 4,919.12 4,919.12 4,919.12 0.92 0.07 0.04 0.010 0.500 CO-42 0.90 3.32 12.0 27.3 0.005 4,918.57 4,918.43 4,918.97 4,918.94 4,919.12 4,919.02 3.59 3.09 2.22 0.010 1.000 CO-43 0.90 3.28 12.0 27.9 0.005 4,918.43 4,918.29 4,918.89 4,918.91 4,918.99 4,918.96 3.56 2.53 1.76 0.010 0.500 CO-44 0.70 2.92 12.0 98.0 0.004 4,918.07 4,917.68 4,918.42 4,918.12 4,918.55 4,918.19 3.06 2.87 2.11 0.010 1.500 CO-45 0.70 2.92 12.0 135.8 0.004 4,917.68 4,917.14 4,918.03 4,917.75 4,918.16 4,917.78 3.06 2.87 1.38 0.010 0.700 27 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203- Page 1 of 1 755-1666 4/19/2016 Bentley StormCAD V8i (SELECTseries 3) 3972700StormCAD.stsw Bentley Systems, Inc. Haestad Methods Solution Center [08.11.03.84] 17 B5 0.02 0.30 7.2 0.01 8.72 0.1 7.3 0.67 8.68 5.8 5.8 0.5 12 50 7.4 0.1 piped to DP11 area sump inlet 10 A10 0.02 0.53 5.0 0.01 9.70 0.1 0.1 0.5 12 24 1.5 0.3 piped to DP11 5' Type R Sump Inlet 11 A11 0.12 1.00 5.0 0.12 9.70 1.2 7.4 0.80 8.64 6.9 6.9 0.5 15 12 5.6 0.0 piped to DP12 Pond A WQ Detention Pond A 12 A12 0.29 0.61 5.0 0.18 9.70 1.7 7.4 2.52 8.62 21.7 piped to offsite MH 18 C1 0.06 0.37 5.0 0.02 9.70 0.2 0.6 0.5 594 1.5 6.4 19 C2 0.13 0.39 5.3 0.05 9.54 0.5 0.6 0.5 400 1.5 4.3 Runoff flows south to Rock Creek Drive C3 0.10 0.48 5.0 0.05 9.70 0.5 than directed east 1.0 0.3 190 2.0 1.6 Runoff flows south to Rock Creek Drive C4 0.09 0.33 5.0 0.03 9.70 0.3 than directed east Street flow offsite C5 0.05 1.00 5.0 0.05 9.70 0.5 11.7 0.18 7.26 1.3 Runoff flows to Ziegler Roand and North offsite Runoff flows to Ziegler Roand andsouth to Rock Creek Drive then directed east 39727.00 PIPE 100-Year DIRECT RUNOFF TOTAL RUNOFF STREET 4/20/16 X:\3970000.all\3972700\Excel\Drainage\3972700 Drainage_Calcs_v2.0.xlsm Page 1 of 1 4/19/2016 5' Type R Sump Inlet 11 A11 0.12 0.85 5.0 0.10 2.78 0.3 7.7 0.68 2.45 1.7 1.7 0.5 15 12 3.4 0.1 piped to DP12 Pond A WQ Detention Pond A 12 A12 0.29 0.49 5.0 0.14 2.78 0.4 7.7 2.12 2.44 5.2 piped to offsite MH 18 C1 0.06 0.30 5.0 0.02 2.78 0.1 0.6 0.1 594 1.5 6.4 19 C2 0.13 0.31 5.3 0.04 2.74 0.1 0.6 0.1 400 1.5 4.3 Runoff flows south to Rock Creek Drive C3 0.10 0.38 5.0 0.04 2.78 0.1 than directed east 1.0 0.1 190 2.0 1.6 Runoff flows south to Rock Creek Drive C4 0.09 0.27 5.0 0.02 2.78 0.1 than directed east Street flow offsite C5 0.05 0.82 5.0 0.04 2.78 0.1 11.7 0.14 2.08 0.3 4/20/16 STANDARD FORM SF-3 STORM DRAINAGE SYSTEM DESIGN (RATIONAL METHOD PROCEDURE) 2-Year 39727.00 Runoff flows to Ziegler Roand and North offsite Runoff flows to Ziegler Roand andsouth to Rock Creek Drive then directed east DIRECT RUNOFF TOTAL RUNOFF STREET PIPE X:\3970000.all\3972700\Excel\Drainage\3972700 Drainage_Calcs_v2.0.xlsm Page 1 of 1 4/19/2016 For non-urbanized basins a minimum t c of 10.0 minutes is required. Table 6-2. NRCS Conveyance Factors, K Nearly bare ground Grassed waterway Paved areas and shallow paved swales Type of Land Surface Heavy Meadow Tillage/field Short pasture and lawns STANDARD FORM SF-2 TIME OF CONCENTRATION SUB-BASIN tc CHECK 39727.00 DATA (URBANIZED BASINS) INITIAL/OVERLAND (Ti) TRAVEL TIME (Tt) X:\3970000.all\3972700\Excel\Drainage\3972700 Drainage_Calcs_v2.0.xlsm Page 1 of 1 4/19/2016