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Home My WebLink AboutWORTHINGTON STORAGE - FDP220016 - SUBMITTAL DOCUMENTS - ROUND 3 - DRAINAGE REPORT FINAL DRAINAGE REPORT WORTHINGTON STORAGE APRIL 26, 2023 NORTHERNENGINEERING.COM 970.221.4158 FORT COLLINS GREELEY This Drainage Report is consciously provided as a PDF. Please consider the environment before printing this document in its entirety. When a hard copy is necessary, we recommend double-sided printing. NORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: WORTHINGTON STORAGE FORT COLLINS | GREELEY COVER LETTER April 26, 2023 City of Fort Collins Stormwater Utility 700 Wood Street Fort Collins, CO 80521 RE: FINAL DRAINAGE REPORT FOR WORTHINGTON STORAGE Dear Staff: Northern Engineering is pleased to submit this Final Drainage Report for your review. This report accompanies the combined Final Development Plan submittal for the proposed Worthington Storage project. This report has been prepared in accordance with the City of Fort Collins Stormwater Criteria Manual (FCSCM) and serves to document the stormwater impacts associated with the proposed Worthington Storage project. We understand that review by the City of Fort Collins is to assure general compliance with standardized criteria contained in the manual. If you should have any questions as you review this report, please feel free to contact us. Sincerely, NORTHERN ENGINEERING SERVICES, INC. MASON RUEBEL, PE Project Engineer NORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: WORTHINGTON STORAGE FORT COLLINS | GREELEY TABLE OF CONTENTS TABLE OF CONTENTS I. I. GENERAL LOCATION AND DESCRIPTION .......................................................... 1 II. II. DRAINAGE BASINS AND SUB-BASINS ............................................................... 4 III. III. DRAINAGE DESIGN CRITERIA .......................................................................... 4 IV. IV. DRAINAGE FACILITY DESIGN ........................................................................... 7 V. V. CONCLUSIONS .............................................................................................. 9 VI. VI. REFERENCES ................................................................................................ 9 TABLES AND FIGURES FIGURE 1: AERIAL PHOTOGRAPH ........................................................................................... 2 FIGURE 2: REGULATORY FLOODPLAINS ................................................................................ 3 TABLE 1: DETENTION POND SUMMARY ................................................................................. 8 APPENDICES APPENDIX A – HYDROLOGIC COMPUTATIONS APPENDIX B – HYDRAULIC COMPUTATIONS APPENDIX C – DETENTION POND & WATER QUALITY COMPUTATIONS APPENDIX D – EROSION CONTROL REPORT APPENDIX E – USDA SOILS REPORT APPENDIX F – EXCERPTS FROM CENTRE FOR ADVANCED TECHNOLOGY 16TH FILING MAP POCKET DR1 – DRAINAGE EXHIBIT NORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: WORTHINGTON STORAGE FORT COLLINS | GREELEY 1 | 11 I. GENERAL LOCATION AND DESCRIPTION A. LOCATION Vicinity Map Figure 1: Vicinty Map Worthington Self Storage project is located in the Southwest Quarter of Section 23, Township 7 North, Range 69 West of the 6th Principal Meridian, City of Fort Collins, County of Larimer, State of Colorado. The project site is bordered to the east by Worthington Circle. The rest of the site is surrounded by a private road and commercial development apart of the Centre for Advanced Technology 10th & 19th Filing. The nearest existing major streets to the project are Worthington Circle and Centre Ave just to the north of the project site. A 15” storm sewer conveys stormwater from the existing project site to the north in an existing piping system along Centre Avenue outletting into Spring Creek. B. DESCRIPTION OF PROPERTY The existing project site comprises of ± 3.2 acres. The existing site will be subdivided into two lots with the proposed development on Lot 1 (1.98ac) and the existing building remaining in Lot 2 (1.22ac). NORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: WORTHINGTON STORAGE FORT COLLINS | GREELEY 2 | 11 The site is currently used as asphalt parking lot with an adjacent 1-story existing building. A subsurface exploration report was completed by Triax Engineering, Inc. on June 4, 2021 (Triax Project No. D21G125). According to Triax Engineering, the site generally consists of clayey sand with groundwater at around 20-ft in depth. Underground detention chambers are proposed with this project. There will be approximately 15-ft of separation from the bottom of the system to groundwater level measured in the Soils report. Advanced Drainage Systems or Ferguson do not have a separation requirement as water is designed to flow freely between the system and adjacent soils. Groundwater levels would only affect total storage volume. The City of Fort Collins requires a minimum of 2-ft separation to groundwater. According to the United States Department of Agriculture (USDA) Natural Resources Conservation Service (NRCS) Soil Survey website: (http://websoilsurvey.nrcs.usda.gov/app/WebSoilSurvey.aspx), the site consists primarily of Nunn Clay loam (Hydrologic Soil Group C) and Kim loam (Hydrologic Soil Group B). The calculations assume a Hydrologic Soil Group of C. Hydrologic Soil Group C has a slow rate of water absorption and infiltration. The proposed development will consist of proposed 3-story enclosed mini-storage building and three other 1-story outdoor garage storage buildings. Other proposed improvements include asphalt drive aisles, sidewalks, and landscaping. There is no increase in impervious area with the proposed project. Existing detention facilities and conveyance methods will be modified and updated to meet the current Fort Collins requirements. This includes modifying the existing detention pond and the addition of underground chambers. Figure 1: Aerial Photograph NORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: WORTHINGTON STORAGE FORT COLLINS | GREELEY 3 | 11 The site is currently zoned as Employment District (E) in Fort Collins. Developments surrounding the project site are zoned as Employment as well and Neighborhood Commercial Districts to the east of Worthington Circle. The proposed uses for the project are consistent with Employment District (E). Per the Centre for Advanced Technology 10th & 16th Filing Final Drainage and Erosion Control Study, the calculated detention volume is 1.51 ac-ft which includes runoff from C.A.T 10th and the adjacent Worthington Circle. The detention storage volume is currently divided between a small detention pond and ponding in the adjacent parking lot through a series of area inlets. There is an existing 15” storm sewer in the northeast corner of the project site with a manhole and restrictor plate down-stream of the existing detention pond. The required release rate per the previous drainage report is 1.91 cfs (2-yr historic). The current release rate will be maintained, but the existing detention and conveyance will be updated to meet the current Fort Collins requirements. Stormwater is conveyed to the north to the storm network in Centre Avenue and is ultimately discharged into Spring Creek. FLOODPLAIN The subject property is not located in a FEMA or City of Fort Collins regulatory floodplain. Figure 2: Regulatory Floodplains NORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: WORTHINGTON STORAGE FORT COLLINS | GREELEY 4 | 11 II. DRAINAGE BASINS AND SUB-BASINS A. MAJOR BASIN DESCRIPTION Worthington Self Storage is within the City of Fort Collins Spring Creek major drainage basin which is centrally located in Fort Collins. The Spring Creek drainage basin extends from Horsetooth Reservoir to the confluence with the Poudre River. It encompasses 9 square miles in central Fort Collins. The basin is dominated by residential development, but also includes open space and areas of commercial development. B. SUB-BASIN DESCRIPTION The outfall for the project site is Spring Creek via the existing 15” storm sewer at the corner of Worthington Circle and the private access road. Per the C.A.T 16th Filing drainage report the existing 15” storm sewer and restrictor plate were sized to convey the calculated 2-yr historic flow (1.91 cfs) and ultimately discharges to Spring Creek. The existing crown of Worthington Circle is the existing spillway for the detention. The existing spillway elevation and location will be maintained in Worthington Circle. The finished floor elevations of the existing and proposed buildings are set 1.5-ft above the crown of Worthington Circle and about 3-ft above the 100-yr WSEL in the underground storage. The existing site can be defined with three (3) sub-basins. These include the drainage from the Centre for Advanced Technology (C.A.T) 10th Filing, Worthington Circle public ROW and the project site, C.A.T 16th Filing. The site does receive notable surface runoff from adjacent properties and is detained and released per the Centre for Advanced Technology 16th Filing Final Drainage and Erosion Control Study. Flows from C.A.T 10th Filing and Worthington Circle will be conveyed through the proposed site and detention volume will be provided onsite. An existing detention volume of 1.51 acft was calculated per the C.A.T 16th Filing report which is currently divided between an existing detention pond and ponding in the adjacent parking lot. Detention storage will be updated to current Fort Collins requirements, but the release rate will be maintained. There is no increase in impervious area with the proposed project. Historic versus proposed impervious areas are documented within Appendix C. With the modification in impervious area LID and water quality treatment will be included with the drainage design. Water quality will also be designed to include Lot 2 of the project site to allow for future development of the rest of the property without additional stormwater facilities. III. DRAINAGE DESIGN CRITERIA A. OPTIONAL REVISIONS There are no optional provisions outside of the Fort Collins Stormwater Manual (FCSM) B. STORMWATER MANAGEMENT STRATEGY The overall stormwater management strategy employed with Worthington Self Storage utilizes the “Four Step Process” to minimize adverse impacts of urbanization on receiving waters. The following is a description of how the proposed development has incorporated each step. Step 1 – Employ Runoff Reduction Practices. The first consideration taken in trying to reduce the stormwater impacts of this development is the site selection itself. By choosing an already NORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: WORTHINGTON STORAGE FORT COLLINS | GREELEY 5 | 11 developed site with public storm sewer currently in place, the burden is significantly less than developing a vacant parcel absent of any infrastructure. Worthington Self Storage aims to reduce runoff peaks, volumes and pollutant loads from frequently occurring storm events (i.e., water quality (i.e., 80th percentile) and 2-year storm events) by implementing Low Impact Development (LID) strategies. Wherever practical, runoff will be routed across landscaped areas or through underground chambers. These LID practices reduce the overall amount of impervious area, while at the same time Minimizing Directly Connected Impervious Areas (MDCIA). The combined LID/MDCIA techniques will be implemented, where practical, throughout the development, thereby slowing runoff and increasing opportunities for infiltration. Step 2 – Implement BMPs that Provide a Water Quality Capture Volume (WQCV) with Slow Release. The efforts taken in Step 1 will help to minimize excess runoff from frequently occurring storm events; however, urban development of this intensity will still have stormwater runoff leaving the site. The primary water quality treatment will occur in underground chambers. The existing movie theater site and surrounding developments do not provide water quality treatment. With this development, WQCV will be provided for 100% for the current site and all of the surrounding properties. Step 3 – Stabilize Drainageways. As stated in Section II.A, above, the site discharges into Spring Creek, however no changes to the channel are proposed with this project. While this step may not seem applicable to Worthington Self Storage, the proposed project indirectly helps achieve stabilized drainageways, nonetheless. Once again, site selection has a positive effect on stream stabilization. By developing with existing stormwater infrastructure, combined with LID and MDCIA strategies, the likelihood of bed and bank erosion is reduced. Furthermore, this project will pay one- time stormwater development fees, as well as ongoing monthly stormwater utility fees, both of which help achieve Citywide drainageway stability. Step 4 – Implement Site Specific and Other Source Control BMPs. The proposed project will provide site specific source controls and improve on historic conditions. Localized trash enclosures within the development will contain and allow for the disposal of solid waste. Standard Operating procedures (SOPs) will be implemented for BMP maintenance of detention ponds, underground chambers, and associated drainage infrastructure to remove sediment accumulation regularly and prolong the design life of the BMPs. C. DEVELOPMENT CRITERIA REFERENCE AND CONSTRAINTS The subject property is part of a Master Drainage Plan for The Centre for Advanced Technology development. An Overall Development Plan (ODP) drainage study is also submitted concurrently with this project. However, stormwater from Worthington Self Storage will generally follow historic patterns and discharge into conveyance structures established as part of the Centre for Advanced Technology 16th Filing. The subject property is an “in-fill” development project as the property is surrounded by currently developed properties and private access roads. The existing 15-inch storm drain will function as the ultimate outfall for the project site. NORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: WORTHINGTON STORAGE FORT COLLINS | GREELEY 6 | 11 D. HYDROLOGICAL CRITERIA The City of Fort Collins Rainfall Intensity-Duration-Frequency Curves, as depicted in Figure 3.4-1 of the FCSCM, serve as the source for all hydrologic computations associated with Worthington Self Storage development. Tabulated data contained in Table 3.4-1 has been utilized for Rational Method runoff calculations. The Rational Method has been employed to compute stormwater runoff utilizing coefficients contained in Tables 3.2-1, 3.2-2, and 3.2-3 of the FCSCM. The Rational Method will be used to estimate peak developed stormwater runoff from drainage basins within the developed site for the 2-year, 10-year, and 100-year design storms. Peak runoff discharges determined using this methodology have been used to check the street capacities, inlets, swales, and storm drain lines. Two separate design storms have been utilized to address distinct drainage scenarios. The first event analyzed is the “Minor” or “Initial” Storm with a 2-year recurrence interval. The second event considered is the “Major Storm” with a 100-year recurrence interval. E. HYDRAULIC CRITERIA The hydraulic analyses of street capacities, inlets, storm drain lines, culverts, and swales are per the FCSM criteria and provided during Final Plan. The following computer programs and methods were utilized: · The storm drain lines were analyzed using Hydraflow Storm Sewer Extension for AutoCAD Civil 3D. · The inlets were analyzed using the Urban Drainage Inlet and proprietary area inlet spreadsheets. · Swales and street capacities were analyzed using the Urban Drainage Channels spreadsheets. F. FLOODPLAIN REGULATIONS COMPLIANCE As previously mentioned, this project is not subject to any floodplain regulations. G. MODIFICATIONS OF CRITERIA No formal modifications are requested at this time. H. CONFORMANCE WITH WATER QUALITY TREATMENT CRITERIA City Code requires that 100% of runoff from a project site receive some sort of water quality treatment. This project proposes to provide the entire water quality treatment with underground chambers. The chambers, when constructed per Fort Collins regulations, are considered an LID treatment method. An exhibit is provided in Appendix C detailing treatment areas and methods. I. CONFORMANCE WITH LOW IMPACT DEVELOPMENT (LID) The project site will conform with the requirement to treat a minimum of 75% of the project site using a LID technique. LID treatment will be provided by underground chambers. Please see Appendix C for LID design information, table, and exhibit(s). Due to the use of underground detention, 100% of the onsite and offsite impervious area will be treated using the underground chamber treatment method. NORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: WORTHINGTON STORAGE FORT COLLINS | GREELEY 7 | 11 IV. DRAINAGE FACILITY DESIGN A. GENERAL CONCEPT The main objective of Worthington Storage drainage design is to maintain existing drainage patterns, while not adversely impacting adjacent properties. There are off-site flows impacting the existing property that are accounted for in the basins described below. A list of tables and figures used within this report can be found in the Table of Contents at the front of the document. The tables and figures are located within the sections to which the content best applies. The project site will be divided into two detention areas and analyzed separately. The two detention areas will tie to the same 15-inch storm drain outfall, and the historic release rate will be split between the two detention areas. Detention Area 1 will be to the north of the main building and include Stormtech Basins 1 & 2 and R-Tank Basin 1. Detention Area 2 will be to the south of the main building and include Stormtech Basins 3, 4 & 5 and R-Tank Basins 2 & 3. Drainage for the project site has been analyzed using seven (7) drainage sub-basins. The drainage patterns anticipated for the basins are further described below. Basin A1 Basin A1 is approximately 0.23 acres and consists of landscaping area and sidewalk in the northeast corner of the site. An area inlet will collect runoff from this basin. A water quality weir will be installed, and water quality treatment will be provided for 100% of Basin A1 (Stormtech Basin 1). Detention will be provided by the R-Tank stormwater system (R-Tank Basin 1) and discharged into the existing 15-inch storm drain outfall. Basin A2 Basin A2 is approximately 0.31 acres and consists of a portion of the parking lot in the northeast corner of the site and adjacent landscaping area. Offsite flow from C.A.T 10th Filing is conveyed in a concrete pan from the north and collected in a proposed curb inlet. The inlet will discharge into underground chambers (Stormtech Basin 2). A water quality weir will be installed, and water quality treatment will be provided for 100% of Basin A2. Detention will be provided by the R-tank stormwater system (R-Tank Basin 1). The detention pond will discharge into the existing 15-inch storm drain outfall. Basin B1 Basin A2 is approximately 1.47 acres and consists of a portion of the proposed building and existing cinema saver building. Runoff from this basin will sheet flow to valley pans in the center of the proposed private access roads. Flow will be collected by an area inlet and discharge into underground chambers. Offsite flow from Basin OS2 is conveyed via curb & gutter and concrete pan from the west and collected in the proposed area inlet. A water quality weir will be installed, and water quality treatment will be provided for 100% of Basin B1 (Stormtech Basin 4). Detention will be provided by the R-Tank and Stormtech stormwater system (Stormtech Basin 5 & R-Tank Basin 2 & 3). Basin B2 Basin B2 is approximately 1.14 acres and consists of a portion of the proposed building and existing cinema saver building. Runoff from this basin will be collected by a proposed NORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: WORTHINGTON STORAGE FORT COLLINS | GREELEY 8 | 11 curb inlet along the private access road. A water quality weir will be installed, and water quality treatment will be provided for 100% of Basin B2 (Stormtech Basin 3). Detention will be provided by the R-Tank and Stormtech stormwater system (Stormtech Basin 5 & R- Tank Basin 2 & 3). Basin OS1 Basin OS1 is approximately 1.93 acres. This basin consists of the existing Centre for Advanced Technology 10th Filing development. The basin will maintain historic drainage patterns from northwest to southeast. Runoff from this basin will sheet flow from the existing structures and parking lots and collect in an existing concrete pan which will tie into Basin A2 and discharge into a proposed curb inlet. Water quality treatment will be provided for 100% of Basin OS1, and detention will be provided by the R-tank and Stormtech stormwater system. Basin OS2 Basin OS2 is approximately 1.57 acres and consists of the existing residential buildings along Shields St and a portion of a private access road along the west side of the site. The basin will generally maintain historic drainage patterns from the southwest to the northeast. Runoff from this basin will sheet flow and collect in a proposed area inlet in Basins B1. Water quality treatment will be provided for 100% of Basin OS2, and detention will be provided by the R-tank and Stormtech stormwater system. Basin OS3 Basin OS3 is approximately 0.32 acres and consists of Worthington Circle. The basin will generally maintain historic drainage patterns. Runoff from this basin will collect in the existing curb and gutter and discharge into a type R inlet at the north corner of the project site. Water quality treatment will be provided for 100% of Basin OS3, and detention will be provided by the R-tank and Stormtech stormwater system. A full-size copy of the Drainage Exhibit can be found in the Map Pocket at the end of this report. B. SPECIFIC DETAILS The Worthington Self Storage project will be utilizing a combination of R-tank modules and Stormtech for detention and Stormtech chambers to fullfill the treatment requirements. Worthington Self Storage will be providing 100% WQCV using LID measures. Detention Summary Description Required Detention Volume (ft3) Design Detention Volume (ft3) Required WQCV (ft3) Design WQCV Volume (ft3) Combined WQCV & Detention Design Total (ft3) Release Rate (cfs) Detention Area 1 30,101 30,138 2,487 2,975 33,113 0.25 Detention Area 2 36,226 36,922 3,777 4,375 41,297 1.66 Totals 66,327 67,060 6,264 7,350 74,410 1.91 Existing -- -- -- -- -- 1.91 Table 1: Detention & WQCV Summary NORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: WORTHINGTON STORAGE FORT COLLINS | GREELEY 9 | 11 CONCLUSIONS C. COMPLIANCE WITH STANDARDS The proposed drainage design for the Worthington Self Storage complies with the City of Fort Collins Stormwater Criteria Manual. The drainage design proposed complies with the City of Fort Collins’ Master Drainage Plan for the Spring Creek Basin. The proposed drainage design complies with the Master Drainage Plan for the existing Centre for Advanced Technology Development (CAT). There are no regulatory floodplains associated with the development The drainage plan and stormwater measurements proposed with Worthington Self Storage are compliant with all applicable State and Federal regulations. D. DRAINAGE CONCEPT 1. The drainage design proposed with this project will effectively limit any potential damage or erosion associated with its stormwater runoff. All existing downstream drainage facilities are expected to not be impacted negatively by this development. 2. The Worthington Storage project will maintain the release rate per the CAT 16th Filing Drainage Report. The existing drainage design has been updated to current City of Fort Collins Standards. This project site provides 100% water quailty treatment through underground chambers. The site meets the requirements set forth by the City of Fort Collins for Low Impact Development (LID) by providing 100% total impervious area being treated through LID treatment. The drainage design will bring the project site and immediate offsite areas into compliance with the current Fort Collins water quality and LID standards. V. REFERENCES 1. City of Fort Collins Landscape Design Guidelines for Stormwater and Detention Facilities, November 5, 2009, BHA Design, Inc. with City of Fort Collins Utility Services. 2. Final Drainage and Erosion Control Study for Cinema Savers Centre for Advanced Technology Sixteenth Filing., RBD, Inc., Fort Collins, Colorado, March 22, 1994. 3. Fort Collins Stormwater Criteria Manual, City of Fort Collins, Colorado, as adopted by Ordinance No. 159, 2018, and referenced in Section 26-500 of the City of Fort Collins Municipal Code. 4. Soils Resource Report for Larimer County Area, Colorado, Natural Resources Conservation Service, United States Department of Agriculture. 5. Urban Storm Drainage Criteria Manual, Volumes 1-3, Urban Drainage and Flood Control District, Wright-McLaughlin Engineers, Denver, Colorado, Revised April 2008. NORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: WORTHINGTON SELF STORAGE FORT COLLINS | GREELEY APPENDIX APPENDIX A HYDROLOGIC COMPUTATIONS Runoff Coefficient1 Percent Impervious1 Project: Location: 0.95 100%Calc. By: 0.95 90%Date: 0.85 90% 0.55 50% 0.20 2% 0.20 2% Basin ID Basin Area (sq.ft.) Basin Area (acres) Asphalt (sq. ft.) Concrete (Sq. Ft.) Asphalt, Concrete (sq.ft.) Asphalt, Concrete (acres) Rooftop (sq.ft.) Rooftop (acres) Lawns, Clayey Soil, Flat Slope < 2% (sq.ft.) Lawns, Clayey Soil, Flat Slope < 2% (acres) Percent Impervious C2*Cf Cf = 1.00 C5*Cf Cf = 1.00 C10*Cf Cf = 1.00 C100*Cf Cf = 1.25 A1 10,174 0.23 0 844 844 0.02 0 0.00 9,330 0.21 10%0.26 0.26 0.26 0.33 A2 13,706 0.31 8651 364 9015 0.21 775 0.02 3,916 0.09 71%0.74 0.74 0.74 0.92 B1 63,888 1.47 26032 3983 30015 0.69 25,663 0.59 8,210 0.19 83%0.85 0.85 0.85 1.00 B2 49,771 1.14 14736 3227 17963 0.41 26,543 0.61 5,265 0.12 84%0.87 0.87 0.87 1.00 OS1 84,018 1.93 46681 0 46681 1.07 10,987 0.25 26,350 0.60 68%0.71 0.71 0.71 0.89 OS2 68,407 1.57 12776 0 12776 0.29 7,812 0.18 47,819 1.10 30%0.43 0.43 0.43 0.53 OS3 14,104 0.32 10004 1405 11409 0.26 0 0.00 2,695 0.06 81%0.81 0.81 0.81 1.00 Detention Area 1 (A1,A2,OS1, OS3)122,002 2.80 65336 2613 67949 1.56 11,762 0.27 42,291 0.97 65%0.69 0.69 0.69 0.86 Detention Area 2 (B1,B2,OS2)182,065 4.18 53544 7210 60754 1.39 60,018 1.38 61,293 1.41 64%0.70 0.70 0.70 0.87 ALL BASINS (A1,A2,B1,B2,OS1,O S2,OS3)304,067 6.98 118880 9823 128703 2.95 71,780 1.65 103,584 2.38 64%0.69 0.69 0.69 0.87 Combined Basins Offsite Basins Lawns and Landscaping: 2) Composite Runoff Coefficient adjusted per Table 3.2-3 of the Fort Collins Stormwater Manual (FCSM). Lawns, Clayey Soil, Flat Slope < 2% USDA SOIL TYPE: C Undeveloped: Greenbelts, Agriculture Composite Runoff Coefficient2 1) Runoff coefficients per Tables 3.2-1 & 3.2 of the FCSM. Percent impervious per Tables 4.1-2 & 4.1-3 of the FCSM. DEVELOPED RUNOFF COEFFICIENT CALCULATIONS Asphalt, Concrete Rooftop Residential: High Density Residential: Low Density Streets, Parking Lots, Roofs, Alleys, and Drives: Character of Surface:Worthington Storage Fort Collins M. Ruebel March 7, 2023 Where: n = Roughness Coefficient R = Hydraulic Radius (feet) S = Longitudinal Slope, feet/feet Length (ft) Slope (%) Ti 2-Yr (min) Ti 10-Yr (min) Ti 100-Yr (min) Length (ft) Slope (%)Surface Flow Area3 (sq.ft.) WP3 (ft)R (ft)V (ft/s) Tt (min) Max. Tc (min) Comp. Tc 2-Yr (min) Tc 2-Yr (min) Comp. Tc 10-Yr (min) Tc 10-Yr (min) Comp. Tc 100- Yr (min) Tc 100-Yr (min) a1 A1 20 2.00%5.56 5.56 5.13 90 2.00%Swale (8:1)0.04 8.00 16.12 0.50 3.30 0.45 10.61 6.02 6.02 6.02 6.02 5.58 5.58 a2 A2 35 2.00%3.20 3.20 1.58 108 0.50%Valley Pan 0.02 6.00 10.25 0.59 4.92 0.37 10.79 3.56 5.00 3.56 5.00 1.95 5.00 b1 B1 12 2.00%1.27 1.27 0.51 260 0.50%Valley Pan 0.02 6.00 10.25 0.59 4.92 0.88 11.51 2.15 5.00 2.15 5.00 1.40 5.00 b2 B2 150 2.00%4.17 4.17 1.82 76 0.50%Gutter 0.02 3.61 19.18 0.19 1.73 0.73 11.26 4.90 5.00 4.90 5.00 2.55 5.00 os1 OS1 160 2.00%7.23 7.23 3.88 190 1.00%Valley Pan 0.02 6.00 10.25 0.59 6.95 0.46 11.94 7.69 7.69 7.69 7.69 4.33 5.00 os2 OS2 150 1.33%14.04 14.04 11.83 190 3.79%Gutter 0.02 3.61 19.18 0.19 6.35 0.50 11.89 14.54 11.89 14.54 11.89 12.32 11.89 os3 OS3 20 2.00%1.95 1.95 0.66 340 1.00%Gutter 0.02 3.61 19.18 0.19 3.26 1.74 12.00 3.68 5.00 3.68 5.00 2.40 5.00 a Detention Area 1 (A1,A2,OS1, OS3)160 2.00%7.70 7.70 4.46 190 1.00%Gutter 0.02 3.61 19.18 0.19 2.45 1.29 11.94 8.99 8.99 8.99 8.99 5.75 5.75 b Detention Area 2 (B1,B2,OS2)150 1.33%8.38 8.38 4.75 190 3.79%Gutter 0.02 3.61 19.18 0.19 4.77 0.66 11.89 9.05 9.05 9.05 9.05 5.42 5.42 Combined Basins Offsite Basins Design Point Basin ID Overland Flow Channelized Flow Time of Concentration NotesV = Velocity (ft/sec)WP = Wetted Perimeter (ft) DEVELOPED TIME OF CONCENTRATION COMPUTATIONS Location: Maximum Tc:Overland Flow, Time of Concentration: Channelized Flow, Velocity:Channelized Flow, Time of Concentration: Worthington Storage Fort Collins M. Ruebel March 7, 2023 Project: Calculations By: Date: (Equation 3.3-2 per Fort Collins Stormwater Manual)𝑅𝑖=1.87 1.1 −𝐶∗𝐶𝑓𝐿 𝑅ൗ13 𝑉=1.49 𝑛∗𝑅2/3 ∗𝑅(Equation 5-4 per Fort Collins) 𝑅𝑐=𝐿 180 +10 (Equation 3.3-5 per Fort Collins Stormwater Manual) 𝑅𝑡=𝐿 𝑉∗60 (Equation 5-5 per Fort Collins 1)Add 5000 to all elevations. 2) Per Fort Collins Stormwater Manual, minimum Tc = 5 min. 3) Assume a water depth of 6" and a typical curb and gutter per Larimer County Urban Street Standard Detail 701 for curb and gutter channelized flow. Assume a water depth of 1', fixed side slopes, and a triangular swale section for grass channelized flow. Assume a water depth of 1', 4:1 side slopes, and a 2' wide valley pan for channelized flow in a valley pan. Tc2 Tc10 Tc100 C2 C10 C100 I2 I10 I100 Q2 Q10 Q100 a1 A1 0.23 6.0 6.0 5.6 0.3 0.3 0.3 2.7 4.6 9.6 0.2 0.3 0.7 a2 A2 0.31 5.0 5.0 5.0 0.7 0.7 0.9 2.9 4.9 10.0 0.7 1.1 2.9 b1 B1 1.47 5.0 5.0 5.0 0.9 0.9 1.0 2.9 4.9 10.0 3.6 6.1 14.6 b2 B2 1.14 5.0 5.0 5.0 0.9 0.9 1.0 2.9 4.9 10.0 2.8 4.8 11.4 os1 OS1 1.93 7.7 7.7 5.0 0.7 0.7 0.9 2.5 4.2 10.0 3.4 5.8 17.1 os2 OS2 1.57 11.9 11.9 11.9 0.4 0.4 0.5 2.1 3.6 7.3 1.4 2.4 6.1 os3 OS3 0.32 5.0 5.0 5.0 0.8 0.8 1.0 2.9 4.9 10.0 0.7 1.3 3.2 a Detention Area 1 2.80 9.0 9.0 5.8 0.7 0.7 0.9 2.4 4.0 9.6 4.5 7.8 23.3 b Detention Area 2 4.18 9.0 9.0 5.4 0.7 0.7 0.9 2.3 3.9 10.0 6.7 11.5 36.3 Combined Basins DEVELOPED DIRECT RUNOFF COMPUTATIONS Intensity (in/hr)Flow (cfs) Worthington Storage M. Ruebel March 7, 2023 Design Point Basin Area (acres) Runoff CTc (Min) Offsite Basins Date: Fort Collins Project: Location: Calc. By: Rational Equation: Q = CiA (Equation 6-1 per MHFD) Intensity, I, from Fig. 3.4.1 Fort Collins Stormwater Manual. FORT COLLINS STORMWATER CRITERIA MANUAL Hydrology Standards (Ch. 5) 3.0 Rational Method 3.4 Intensity-Duration-Frequency Curves for Rational Method Page 8 Table 3.4-1. IDF Table for Rational Method Duration (min) Intensity 2-year (in/hr) Intensity 10-year (in/hr) Intensity 100-year (in/hr) Duration (min) Intensity 2-year (in/hr) Intensity 10-year (in/hr) Intensity 100-year (in/hr) 5 2.85 4.87 9.95 39 1.09 1.86 3.8 6 2.67 4.56 9.31 40 1.07 1.83 3.74 7 2.52 4.31 8.80 41 1.05 1.80 3.68 8 2.40 4.10 8.38 42 1.04 1.77 3.62 9 2.30 3.93 8.03 43 1.02 1.74 3.56 10 2.21 3.78 7.72 44 1.01 1.72 3.51 11 2.13 3.63 7.42 45 0.99 1.69 3.46 12 2.05 3.50 7.16 46 0.98 1.67 3.41 13 1.98 3.39 6.92 47 0.96 1.64 3.36 14 1.92 3.29 6.71 48 0.95 1.62 3.31 15 1.87 3.19 6.52 49 0.94 1.6 3.27 16 1.81 3.08 6.30 50 0.92 1.58 3.23 17 1.75 2.99 6.10 51 0.91 1.56 3.18 18 1.70 2.90 5.92 52 0.9 1.54 3.14 19 1.65 2.82 5.75 53 0.89 1.52 3.10 20 1.61 2.74 5.60 54 0.88 1.50 3.07 21 1.56 2.67 5.46 55 0.87 1.48 3.03 22 1.53 2.61 5.32 56 0.86 1.47 2.99 23 1.49 2.55 5.20 57 0.85 1.45 2.96 24 1.46 2.49 5.09 58 0.84 1.43 2.92 25 1.43 2.44 4.98 59 0.83 1.42 2.89 26 1.4 2.39 4.87 60 0.82 1.4 2.86 27 1.37 2.34 4.78 65 0.78 1.32 2.71 28 1.34 2.29 4.69 70 0.73 1.25 2.59 29 1.32 2.25 4.60 75 0.70 1.19 2.48 30 1.30 2.21 4.52 80 0.66 1.14 2.38 31 1.27 2.16 4.42 85 0.64 1.09 2.29 32 1.24 2.12 4.33 90 0.61 1.05 2.21 33 1.22 2.08 4.24 95 0.58 1.01 2.13 34 1.19 2.04 4.16 100 0.56 0.97 2.06 35 1.17 2.00 4.08 105 0.54 0.94 2.00 36 1.15 1.96 4.01 110 0.52 0.91 1.94 37 1.16 1.93 3.93 115 0.51 0.88 1.88 38 1.11 1.89 3.87 120 0.49 0.86 1.84 FORT COLLINS STORMWATER CRITERIA MANUAL Hydrology Standards (Ch. 5) 3.0 Rational Method 3.4 Intensity-Duration-Frequency Curves for Rational Method Page 9 Figure 3.4-1. Rainfall IDF Curve – Fort Collins NORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: WORTHINGTON SELF STORAGE FORT COLLINS | GREELEY APPENDIX APPENDIX B HYDRAULIC COMPUTATIONS NNORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: WORTHINGTON SELF STORAGE FORT COLLINS | GREELEY APPENDIX INLET CALCULATIONS Project #: Project Name: Project Loc.: Design Flowrate Upstream Flowrate Total Flowrate Allowable Flowrate Overflow Design Flowrate Upstream Flowrate Total Flowrate Allowable Flowrate Overflow Design Flowrate Upstream Flowrate Total Flowrate Allowable Flowrate Overflow Inlet C3 Designed for Basins A2 & OS1.Triple Combination 4.10 cfs 0.00 cfs 4.10 cfs 10.50 cfs 0.00 cfs 6.90 cfs 0.00 cfs 6.90 cfs 22.20 cfs 0.00 cfs 20.00 cfs 0.00 cfs 20.00 cfs 22.20 cfs 0.00 cfs Inlet D3 Designed for Basin A1 FC Single Area Inlet 0.20 cfs 0.00 cfs 0.20 cfs 5.11 cfs 0.00 cfs 0.30 cfs 0.00 cfs 0.30 cfs 5.11 cfs 0.00 cfs 0.70 cfs 0.00 cfs 0.70 cfs 5.11 cfs 0.00 cfs Inlet D4 Designed for Basin OS3.5' Type-R 0.70 cfs 0.00 cfs 0.70 cfs 5.40 cfs 0.00 cfs 1.30 cfs 0.00 cfs 1.30 cfs 10.70 cfs 0.00 cfs 3.20 cfs 0.00 cfs 3.20 cfs 10.70 cfs 0.00 cfs Inlet E3 Designed for Basin B2.Double Combination 2.80 cfs 0.00 cfs 2.80 cfs 5.30 cfs 0.00 cfs 4.80 cfs 0.00 cfs 4.80 cfs 15.10 cfs 0.00 cfs 11.40 cfs 0.00 cfs 11.40 cfs 15.10 cfs 0.00 cfs Inlet F2-1 Designed for Basins B1 & OS2.FC Quad Area Inlet 5.00 cfs 0.00 cfs 5.00 cfs 19.27 cfs 0.00 cfs 8.50 cfs 0.00 cfs 8.50 cfs 21.55 cfs 0.00 cfs 20.70 cfs 0.00 cfs 20.70 cfs 21.55 cfs 0.00 cfs INLET CAPACITIES SUMMARY Inlet Type Inlet and Area Drain Capacities 2-Year 100-Year 1853-001 Worthington Storage Fort Collins, Colorado Basins / Design Notes 10-Year Project: Inlet ID: Gutter Geometry: Maximum Allowable Width for Spread Behind Curb TBACK =18.0 ft Side Slope Behind Curb (leave blank for no conveyance credit behind curb)SBACK =0.050 ft/ft Manning's Roughness Behind Curb (typically between 0.012 and 0.020)nBACK =0.012 Height of Curb at Gutter Flow Line HCURB =6.00 inches Distance from Curb Face to Street Crown TCROWN =24.0 ft Gutter Width W =2.00 ft Street Transverse Slope SX =0.020 ft/ft Gutter Cross Slope (typically 2 inches over 24 inches or 0.083 ft/ft)SW =0.083 ft/ft Street Longitudinal Slope - Enter 0 for sump condition SO =0.000 ft/ft Manning's Roughness for Street Section (typically between 0.012 and 0.020)nSTREET =0.012 Minor Storm Major Storm Max. Allowable Spread for Minor & Major Storm TMAX =15.0 15.0 ft Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX =6.0 12.0 inches Check boxes are not applicable in SUMP conditions 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 MHFD-Inlet, Version 5.01 (April 2021) ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm) (Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread) Worthington Self Storage Inlet C3 MHFD-Inlet_v5.01.xlsm, Inlet C3 3/7/2023, 6:53 PM Design Information (Input)MINOR MAJOR Type of Inlet Type = Local Depression (additional to continuous gutter depression 'a' from above)alocal =3.00 3.00 inches Number of Unit Inlets (Grate or Curb Opening)No =2 2 Water Depth at Flowline (outside of local depression)Ponding Depth =6.0 9.0 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 2.3-3.7)Cw (C) =3.60 3.60 Curb Opening Orifice Coefficient (typical value 0.60 - 0.70)Co (C) =0.67 0.67 Low Head Performance Reduction (Calculated)MINOR MAJOR Depth for Grate Midwidth dGrate =N/A N/A ft Depth for Curb Opening Weir Equation dCurb =0.33 0.58 ft Combination Inlet Performance Reduction Factor for Long Inlets RFCombination =0.57 0.85 Curb Opening Performance Reduction Factor for Long Inlets RFCurb =0.93 1.00 Grated Inlet Performance Reduction Factor for Long Inlets RFGrate =N/A N/A MINOR MAJOR Total Inlet Interception Capacity (assumes clogged condition)Qa =10.5 22.2 cfs Inlet Capacity IS GOOD for Minor and Major Storms(>Q PEAK)Q PEAK REQUIRED =4.1 20.0 cfs CDOT Type R Curb Opening INLET IN A SUMP OR SAG LOCATION MHFD-Inlet, Version 5.01 (April 2021) H-VertH-Curb W Lo (C) Lo (G) Wo WP CDOT Type R Curb Opening Override Depths MHFD-Inlet_v5.01.xlsm, Inlet C3 3/7/2023, 6:53 PM Inlet Name:Inlet D3 Project: 10-Year Design Flow (cfs)0.30 Location: 100-Year Design Flow (cfs)0.70 Calc. By: Type of Grate:2.67 Length of Grate (ft):1.98 5,051.53 Width of Grate (ft):1.35 0.50 Depth Above Inlet (ft)Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs)Notes 0.00 5,051.53 0.00 0.00 0.00 0.10 5,051.63 0.32 2.27 0.32 10-Year Storm 0.17 5,051.70 0.70 2.96 0.70 100-Year Storm 0.27 5,051.80 1.40 3.73 1.40 0.37 5,051.90 2.25 4.37 2.25 0.47 5,052.00 3.22 4.92 3.22 0.57 5,052.10 4.30 5.42 4.30 0.64 5,052.17 5.11 5.75 5.11 Overflow into Street 0.67 5,052.20 5.48 5.88 5.48 0.77 5,052.30 6.75 6.30 6.75 0.87 5,052.40 8.11 6.70 6.70 0.97 5,052.50 9.54 7.07 7.07 Depth vs. Flow Fort Collins Area Inlet 1853-001 Worthington Self Storage M. Ruebel Reduction Factor: AREA INLET PERFORMANCE CURVE Governing Equations If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters Rim Elevation (ft): Open Area of Grate (ft2): 0.00 2.00 4.00 6.00 8.00 10.00 12.00 0.00 0.20 0.40 0.60 0.80 1.00 1.20Discharge (cfs)Stage (ft) Stage -Discharge Curves Series1 Series2 At low flow dephs, the inlet will act like a weir governed by the following equation: * where P = 2(L + W) * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of the inlet grate * where H corresponds to the depth of water above the centroid of the cross-sectional area (A). 𝑃=3.0𝑃𝐻1.5 𝑃=0.67𝐴(2𝑔𝐻)0.5 NORTHERNENGINEERING.COM | 970.221.4158 FORT COLLINS | GREELEY Project: Inlet ID: Gutter Geometry: Maximum Allowable Width for Spread Behind Curb TBACK =15.7 ft Side Slope Behind Curb (leave blank for no conveyance credit behind curb)SBACK =ft/ft Manning's Roughness Behind Curb (typically between 0.012 and 0.020)nBACK =0.020 Height of Curb at Gutter Flow Line HCURB =6.00 inches Distance from Curb Face to Street Crown TCROWN =15.7 ft Gutter Width W =2.00 ft Street Transverse Slope SX =0.042 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 =0.012 Minor Storm Major Storm Max. Allowable Spread for Minor & Major Storm TMAX =15.0 15.0 ft Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX =6.0 12.0 inches Check boxes are not applicable in SUMP conditions 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 MHFD-Inlet, Version 5.01 (April 2021) ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm) (Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread) Worthington Self Storage Inlet D4 1 Design Information (Input)MINOR MAJOR Type of Inlet Type = Local Depression (additional to continuous gutter depression 'a' from above)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 9.0 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 2.3-3.7)Cw (C) =3.60 3.60 Curb Opening Orifice Coefficient (typical value 0.60 - 0.70)Co (C) =0.67 0.67 Low Head Performance Reduction (Calculated)MINOR MAJOR Depth for Grate Midwidth dGrate =N/A N/A ft Depth for Curb Opening Weir Equation dCurb =0.33 0.58 ft Combination Inlet Performance Reduction Factor for Long Inlets RFCombination =0.77 1.00 Curb Opening Performance Reduction Factor for Long Inlets RFCurb =1.00 1.00 Grated Inlet Performance Reduction Factor for Long Inlets RFGrate =N/A N/A MINOR MAJOR Total Inlet Interception Capacity (assumes clogged condition)Qa =5.4 10.7 cfs Inlet Capacity IS GOOD for Minor and Major Storms(>Q PEAK)Q PEAK REQUIRED =0.7 3.2 cfs CDOT Type R Curb Opening INLET IN A SUMP OR SAG LOCATION MHFD-Inlet, Version 5.01 (April 2021) H-VertH-Curb W Lo (C) Lo (G) Wo WP CDOT Type R Curb Opening Override Depths 1 Project: Inlet ID: Gutter Geometry: Maximum Allowable Width for Spread Behind Curb TBACK =13.0 ft Side Slope Behind Curb (leave blank for no conveyance credit behind curb)SBACK =0.020 ft/ft Manning's Roughness Behind Curb (typically between 0.012 and 0.020)nBACK =0.012 Height of Curb at Gutter Flow Line HCURB =6.00 inches Distance from Curb Face to Street Crown TCROWN =15.0 ft Gutter Width W = 2.00 ft Street Transverse Slope SX =0.020 ft/ft Gutter Cross Slope (typically 2 inches over 24 inches or 0.083 ft/ft)SW =0.083 ft/ft Street Longitudinal Slope - Enter 0 for sump condition SO =0.000 ft/ft Manning's Roughness for Street Section (typically between 0.012 and 0.020)nSTREET =0.012 Minor Storm Major Storm Max. Allowable Spread for Minor & Major Storm TMAX =15.0 15.0 ft Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX =6.0 12.0 inches Check boxes are not applicable in SUMP conditions 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 MHFD-Inlet, Version 5.01 (April 2021) ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm) (Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread) Worthington Self Storage Inlet E3 MHFD-Inlet_v5.01.xlsm, Inlet E3 4/25/2023, 10:23 PM Design Information (Input)MINOR MAJOR Type of Inlet Type = Local Depression (additional to continuous gutter depression 'a' from above)alocal =2.00 2.00 inches Number of Unit Inlets (Grate or Curb Opening)No = 2 2 Water Depth at Flowline (outside of local depression) Ponding Depth = 6.0 9.0 inches Grate Information MINOR MAJOR Length of a Unit Grate Lo (G) =3.00 3.00 feet Width of a Unit Grate Wo =1.73 1.73 feet Area Opening Ratio for a Grate (typical values 0.15-0.90)Aratio =0.43 0.43 Clogging Factor for a Single Grate (typical value 0.50 - 0.70)Cf (G) =0.50 0.50 Grate Weir Coefficient (typical value 2.15 - 3.60)Cw (G) =3.30 3.30 Grate Orifice Coefficient (typical value 0.60 - 0.80)Co (G) =0.60 0.60 Curb Opening Information MINOR MAJOR Length of a Unit Curb Opening Lo (C) =3.00 3.00 feet Height of Vertical Curb Opening in Inches Hvert =6.50 6.50 inches Height of Curb Orifice Throat in Inches Hthroat =5.25 5.25 inches Angle of Throat (see USDCM Figure ST-5)Theta = 0.00 0.00 degrees Side Width for Depression Pan (typically the gutter width of 2 feet)Wp =2.00 2.00 feet Clogging Factor for a Single Curb Opening (typical value 0.10)Cf (C) =0.10 0.10 Curb Opening Weir Coefficient (typical value 2.3-3.7)Cw (C) =3.70 3.70 Curb Opening Orifice Coefficient (typical value 0.60 - 0.70)Co (C) =0.66 0.66 Low Head Performance Reduction (Calculated)MINOR MAJOR Depth for Grate Midwidth dGrate =0.523 0.773 ft Depth for Curb Opening Weir Equation dCurb =0.33 0.58 ft Combination Inlet Performance Reduction Factor for Long Inlets RFCombination =0.71 1.00 Curb Opening Performance Reduction Factor for Long Inlets RFCurb =1.00 1.00 Grated Inlet Performance Reduction Factor for Long Inlets RFGrate =0.71 1.00 MINOR MAJOR Total Inlet Interception Capacity (assumes clogged condition)Qa =5.3 15.1 cfs Inlet Capacity IS GOOD for Minor and Major Storms(>Q PEAK)Q PEAK REQUIRED =2.8 11.4 cfs CDOT/Denver 13 Combination INLET IN A SUMP OR SAG LOCATION MHFD-Inlet, Version 5.01 (April 2021) H-VertH-Curb W Lo (C) Lo (G) Wo WP CDOT/Denver 13 Combination Override Depths MHFD-Inlet_v5.01.xlsm, Inlet E3 4/25/2023, 10:23 PM Inlet Name:Inlet F2-1 Project: 10-Year Design Flow (cfs)8.50 Location: 100-Year Design Flow (cfs)20.70 Calc. By: Type of Grate:10.69 Length of Grate (ft):7.92 5,051.69 Width of Grate (ft):1.35 0.50 Depth Above Inlet (ft)Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs)Notes 0.00 5,051.69 0.00 0.00 0.00 0.20 5,051.89 2.49 12.85 2.49 0.40 5,052.09 7.04 18.17 7.04 2-Year Storm 0.60 5,052.29 12.92 22.25 12.92 10-Year Storm 0.80 5,052.49 19.90 25.70 19.90 100-Year Storm 1.00 5,052.69 27.81 28.73 28.73 1.20 5,052.89 36.56 31.47 31.47 1.40 5,053.09 46.07 33.99 33.99 1.60 5,053.29 56.28 36.34 36.34 1.80 5,053.49 67.16 38.55 38.55 2.00 5,053.69 78.66 40.63 40.63 2.20 5,053.89 90.75 42.61 42.61 AREA INLET PERFORMANCE CURVE Governing Equations If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters Rim Elevation (ft): Open Area of Grate (ft2): Depth vs. Flow Fort Collins Area Inlet 1853-001 Worthington Self Storage M. Ruebel Reduction Factor: 0.00 10.00 20.00 30.00 40.00 50.00 60.00 70.00 80.00 90.00 100.00 0.00 0.50 1.00 1.50 2.00 2.50Discharge (cfs)Stage (ft) Stage - Discharge Curves Series1 Series2 Atlow flow dephs, the inlet will act like a weir governed by the following equation: * where P = 2(L + W) * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of the inlet grate * where H corresponds to the depth of water above the centroid of the cross-sectional area (A). = 3.0 . = 0.67 (2 ). NORTHERNENGINEERING.COM | 970.221.4158 FORT COLLINS | GREELEY NNORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: TIMBER LARK RESIDENTIAL FORT COLLINS | GREELEY APPENDIX STORM SEWER CALCULATIONS (100-YEAR) NNORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: WORTHINGTON SELF STORAGE FORT COLLINS | GREELEY APPENDIX STORM SEWER CALCULATIONS (2-YEAR/WQ) INLET TO STORMTECH ISOLATOR ROW NORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: WORTHINGTON SELF STORAGE FORT COLLINS | GREELEY APPENDIX APPENDIX C DETENTION POND & WATER QUALITY COMPUTATIONS Project Number:Project:Worthington Storage Project Location:Date:April 25, 2023 Description Historic Site 1.91 cfs Description Detention Area 1 0.25 cfs Detention Area 2 1.66 cfs Total release rate 1.91 cfs Required release rate 1.91 cfs Underground Vault R-Tank Basin 1 30,138 cu. ft. R-Tank Basin 2 19,024 cu. ft. R-Tank Basin 3 11,195 cu. ft. Stormtech Basin 5 6,703 cu. ft. Total of Detention Area 1 30,138 cu. ft. Req. Vol. of Detention Area 1 30,101 cu. ft. Total of Detention Area 2 36,922 cu. ft. Req. Vol. of Detention Area 2 36,226 cu. ft. Underground Vault Chambers Required Notes Stormtech Basin 1 525 cu. ft. 3 - MC 3500 Design water quality volume for Basins A1 & OS3. Req. Vol. Stormtech Basin 1 408 cu. ft. Required water quality volume for Basins A1 & OS3. Stormtech Basin 2 2,450 cu. ft. 14 - MC 3500 Design water quality volume for Basins A2 & OS1. Req. Vol. Stormtech Basin 2 2,079 cu. ft. Required water quality volume for Basins A2 & OS1. Stormtech Basin 3 1,575 cu. ft. 16 - MC 3500 Design water quality volume for Basins B2. Req. Vol. Stormtech Basin 3 1,410 cu. ft. Required water quality volume for Basins B2. Stormtech Basin 4 2,800 cu. ft. 9 - MC 3500 Design water quality volume for Basin B1 & OS2. Req. Vol. Stormtech Basin 4 2,367 cu. ft. Required water quality volume for Basin B1 & OS2. Release rate for Detention Area 2. Total design volume of R-Tanks in Detention Area 1. Total design volume of R-Tanks in Detention Area 2. Summary of Water Quality Volumes per Stormtech Basin Volume Required detention volume of Detention Area 1. Required detention volume of Detention Area 2. Release rate for Detention Area 2. Total release rate for Detention Areas 1 and 2. Notes Release rate for Detention Area 1. Release rate for Detention Area 2. Notes: RELEASE RATE AND SUMMARY OF DETENTION VOLUMES 1853-001 Fort Colins Historic Release Rate Q100 Developed Release Rate Release rate per Centre for Advanced Technology 10th & 16th. Notes Release rate per Centre for Advanced Technology 10th & 16th. Summary of Detention Volumes per R-Tank Basin Volume Notes Q100 Release rate for Detention Area 1 (R-Tank Basin 1) Release rate for Detention Area 2 (R-Tank Basin 2, 3 & Stormtech Basin 5) 1) Detention Area 1 includesBasins A1, A2, OS1, and OS3. 2) Detention Area 2 includes Basins B1, B2, and OS2. 1 TFUD UD UDUDUDUDUDUD EUD UD XXXCVAULTELECELECCELECEDDDTCONTROLIRRGXVAULTF.O.b2b1OS3OS1OS21.93 ac.OS11.57 ac.OS20.31 ac.A21.47 ac.B11.14 ac.B20.33 ac.OS30.23 ac.A1a2R-TANKBASIN 2R-TANKBASIN 1STORMTECHBASIN 1STORMTECHBASIN 2R-TANKBASIN 1STORMTECHBASIN 4STORMTECHBASIN 3STORMTECHBASIN 5R-TANKBASIN 3a1DRAWN BY:SCALE:DATE:DETENTION AREA EXHIBITSHEET NO:FORT COLLINS: 301 North Howes Street, Suite 100, 80521GREELEY: 820 8th Street, 80631ENGINEERNGIEHTRONRN970.221.4158northernengineering.comP:\1853-001\DWG\DRNG\1853-001_DET.DWG WORTHINGTON ENCLOSED MINI-STORAGEFORT COLLINSCOLORADOMCR1" = 70'12/21/2022W O R T H I N G T O N C I R C L E PROPOSED STORM SEWERPROPOSED CURB & GUTTERPROPERTY BOUNDARYPROPOSED INLETADESIGN POINTDRAINAGE BASIN LABELDRAINAGE BASIN BOUNDARYALEGEND:FOR DRAINAGE REVIEW ONLYNOT FOR CONSTRUCTION( IN FEET )1 inch = ft.Feet0707070LOT 1LOT 2PROPOSED BASINw/ WQ WEIRPROPOSED BOXw/ WQ WEIRPROPOSED BASINw/WQ WEIRPROPOSED BASINw/ WQ WEIRDETENTION AREA 1 MC-3500 STORMTECH CHAMBERS(ISOLATOR ROW)DETENTION AREA 2R-TANK STORMWATER MODULESDeveloped Release RateDescriptionQ100NotesDetention Area 10.25cfsRelease rate for Detention Area 1 (R-Tank Basin 1)Detention Area 21.66cfsRelease rate for Detention Area 2 (R-Tank Basin 2, 3 & Stormtech Basin 5)Total release rate1.91cfsTotal release rate for Detention Areas 1 and 2.Required release rate1.91cfsRelease rate per Centre for Advanced Technology 10th & 16th.Summary of Detention Volumes per R-Tank BasinUnderground VaultVolumeNotesR-Tank Basin 130,138cu. ft.Release rate for Detention Area 1.R-Tank Basin 219,024cu. ft.Release rate for Detention Area 2.R-Tank Basin 311,195cu. ft.Release rate for Detention Area 2.Stormtech Basin 56,703cu. ft.Release rate for Detention Area 2.Total of Detention Area 130,138cu. ft.Total design volume of R-Tanks in Detention Area 1.Req. Vol. of Detention Area 130,101cu. ft.Required detention volume of Detention Area 1.Total of Detention Area 236,922cu. ft.Total design volume of R-Tanks in Detention Area 2.Req. Vol. of Detention Area 236,226cu. ft.Required detention volume of Detention Area 2.Summary of Water Quality Volumes per Stormtech BasinUnderground VaultVolumeChambersRequiredNotesStormtech Basin 1525cu. ft.3 - MC 3500Design water quality volume for Basins A1 & OS3.Req. Vol. Stormtech Basin 1408cu. ft.Required water quality volume for Basins A1 & OS3.Stormtech Basin 22,450cu. ft.14 - MC 3500Design water quality volume for Basins A2 & OS1.Req. Vol. Stormtech Basin 22,079cu. ft.Required water quality volume for Basins A2 & OS1.Stormtech Basin 31,575cu. ft.16 - MC 3500Design water quality volume for Basins B2.Req. Vol. Stormtech Basin 31,410cu. ft.Required water quality volume for Basins B2.Stormtech Basin 42,800cu. ft.9 - MC 3500Design water quality volume for Basin B1 & OS2.Req. Vol. Stormtech Basin 42,367cu. ft.Required water quality volume for Basin B1 & OS2. NNORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: TIMBER LARK RESIDENTIAL FORT COLLINS | GREELEY APPENDIX DETENTION AREA 1 Date:03/07/23 Pond No.: 1 100-yr WQCV 0 ft3 0.86 Quantity Detention 30101 ft3 2.80 acres Total Volume 30101 ft3 0.25 cfs Total Volume 0.691 ac-ft Time Time Ft.Collins 100-yr Intensity Q100 Inflow (Runoff) Volume Outflow (Release) Volume Storage Detention Volume (mins)(secs)(in/hr)(cfs)(ft3)(ft3)(ft3) 5 300 9.95 24.0 7188 75 7113 10 600 7.72 18.6 11154 150 11004 15 900 6.52 15.7 14130 225 13905 20 1200 5.60 13.5 16182 300 15882 25 1500 4.98 12.0 17988 375 17613 30 1800 4.52 10.9 19591 450 19141 35 2100 4.08 9.8 20632 525 20107 40 2400 3.74 9.0 21614 600 21014 45 2700 3.46 8.3 22496 675 21821 50 3000 3.23 7.8 23334 750 22584 55 3300 3.03 7.3 24078 825 23253 60 3600 2.86 6.9 24793 900 23893 65 3900 2.72 6.5 25544 975 24569 70 4200 2.59 6.2 26194 1050 25144 75 4500 2.48 6.0 26873 1125 25748 80 4800 2.38 5.7 27509 1200 26309 85 5100 2.29 5.5 28123 1275 26848 90 5400 2.21 5.3 28737 1350 27387 95 5700 2.13 5.1 29236 1425 27811 100 6000 2.06 5.0 29763 1500 28263 105 6300 2.00 4.8 30341 1575 28766 110 6600 1.94 4.7 30832 1650 29182 115 6900 1.89 4.6 31403 1725 29678 120 7200 1.84 4.4 31901 1800 30101 Detention Pond Calculation | FAA Method Project: Project Location: Calculations By: Worthington Storage Fort Collins, Colorado M. Ruebel Detention Area 1 Developed "C" = Area (A)= Max Release Rate = Input Variables Results Design Point Required Detention Volume Design Storm 1 Project Name Date 4/25/2023 City/County State CO Designed By MCR Primary Unit HD Triple Base Material Stone XD Stack 1 Base Thickness 6 in Backfill Material Stone Secondary Unit HD Triple+Mini XD Stack 60 Primary Unit Invert 5045.74 Treatment Row Unit Top Backfill Thickness 12 in Load Rating HS-20 Secondary Unit Invert 5045.74 Finished Surface Type Asphalt Top Backfill Thickness 12 in R-Unit Footprint 5,560.50 sf Access Unit Invert 100.00 R-Unit Units 1806.00 Top Backfill Thickness 12 in R-Unit Perimeter 649.50 ft. Use Stone Storage Yes R-Unit Footprint 2,263.00 sf Use Stone Base for Storage Yes R-Unit Units 735.00 Use Stone Cover for Storage Yes Stone Void Ratio 40% Excavation Footprint 6,906.01 sf Excavation Perimeter 579.00 ft.Treatment Unit Footprint 00.00 sf R-Unit Units 0.00 Treatment Unit Perimeter 00.00 ft. Geogrid Footprint 8,678.81 sf Geogrid Material ACF BX-12 # of Maintenance Ports 7 # of Inspection Ports 2 Material N080 Non-Woven Geotextile Optional Bottom Yes Material N080 Non-Woven Geotextile Location Top Yes Top Bottom Yes Bottom Sides Yes Sides Secondary Elevations 30 mil. PVCGeotextile Excavation Wrap Liner Liner Material Geotextile Unit Wrap Treatment Row Port Quantities Loading Criteria Primary Units Primary Elevations Treatment Row Units Secondary Units (Duel Height System) Access Unit Elevations R-TANK SUBSURFACE STORAGE SYSTEM DESIGN TOOL R-Unit Inputs Base and Top Backfill Material Worthington Storage - R-TANK BASIN 1 Fort Collins Total R-Unit Footprint and Perimeter Secondary R-Unit Footprint Excavation Footprint and Perimeter Geogrid Footprint Stone Storage Page 1 of 3 Project Name Worthington Storage - R-TANK BASIN 1 Date 4/25/2023 Location Fort Collins, CO Designed By MCR Unit Inv.Unit Top Top Stone Min. Grade Max Grade 5045.74 5049.94 5050.94 5051.61 5056.93 5045.74 5050.66 5051.66 5052.33 5057.65 Storage Capcacity Desired Storage Volume Total Volume Provided in R-Unit: Total Volume Provided in Stone: Provided Storage Volume: Elev.Volume Surplus Units Number of Primary Units: Number of Secondary Units: # of Maintenance Ports: Number of Access Units: # of Inspection Ports: Required Backfill Material: Estimated Geotextile Unit Wrap:(1770 sy) Estimated Geotextile Excavation Wrap:(2240 sy) Estimated Liner:(0 sy) Estimated Geogrid:(1109 sy) Estimated Treatment Row Wrap:(0 sy) Estimated Treatment Row Base Fabric:(0 sy) Treatment Units 1 Input Elev. Output Vol. Full Storage 735 30,101 cf Full Storage Capacity Stage Volume Capacity System Quantities Difference = 1,071 Primary Units 30,138.87 cf 6,403.61 cf 23,735.26 cf System Storage Capacities Base Inv. 5,045.24 5,045.24Secondary Units 0 sf System Elevations R-TANK SUBSURFACE STORAGE SYSTEM DESIGN TOOL Elevations 9,981 sf 0 sf 7 0 sf 15,926 sf 20,160 sf 0 2 593 cy Page 2 of 3 Project Name Worthington Storage - R-TANK BASIN 1 Date 4/25/2023 Location Fort Collins, CO Designed By MCR Total Volume Provided in R-Unit: Total Volume Provided in Stone: Provided Storage Volume: Stage Storage Increment 0.50 ft Elevation Volume 5,045.24 0.00 5,045.74 1,381.20 5,046.24 4,291.54 5,046.74 7,201.88 5,047.24 10,112.22 5,047.74 13,022.56 5,048.24 15,932.90 5,048.74 18,843.24 5,049.24 21,753.58 5,049.74 24,663.92 5,050.24 26,469.95 5,050.74 28,863.78 5,051.24 29,757.18 5,051.66 30,138.87 R-Unit Stage Storage Table R-TANK SUBSURFACE STORAGE SYSTEM DESIGN TOOL System Storage Capacities 23,735.26 cf 6,403.61 cf 30,138.87 cf Page 3 of 3 Project Number: Project Name: Project Location: Pond No:Calc. By:M. Ruebel Orifice Dia (in):1 7/8 Orifice Area (sf):0.02 Orifice invert (ft):5,044.99 Orifice Coefficient:0.65 Elevation Stage (ft)Velocity (ft/s)Flow Rate (cfs)Comments 5,044.99 0.00 0.00 0.00 5,045.49 0.50 3.69 0.07 5,045.99 1.00 5.21 0.10 5,046.49 1.50 6.39 0.12 5,046.99 2.00 7.37 0.14 5,047.49 2.50 8.24 0.15 5,047.99 3.00 9.03 0.17 5,048.49 3.50 9.75 0.18 5,048.99 4.00 10.43 0.19 5,049.49 4.50 11.06 0.21 5,049.99 5.00 11.66 0.22 5,050.49 5.50 12.23 0.23 5,050.99 6.00 12.77 0.24 5,051.34 6.35 13.14 0.25 5,051.49 6.50 13.29 0.25 5,051.66 6.67 13.47 0.25 100-Year Storm/Top of R-Tank Basin 1 Orifice Rating Curve ORIFICE RATING CURVE 1853-001 Worthington Storage Fort Collins Detention Area 1 Orifice Design Data Detention Area 1 NORTHERNENGINEERING.COM | 970.221.4158 FORT COLLINS | GREELEY Stormwater Facility Name: Facility Location & Jurisdiction: User Input: Watershed Characteristics User Defined User Defined User Defined User Defined Selected BMP Type =EDB Stage [ft]Area [ft^2]Stage [ft]Discharge [cfs] Watershed Area =2.80 acres 0.00 4,291 0.00 0.00 Watershed Length =400 ft 1.00 4,291 1.00 0.10 Watershed Length to Centroid =200 ft 2.00 5,820 2.00 0.14 Watershed Slope =0.020 ft/ft 3.00 5,820 3.00 0.17 Watershed Imperviousness =65.0%percent 4.00 7,641 4.00 0.20 Percentage Hydrologic Soil Group A =0.0%percent 5.00 4,716 5.00 0.22 Percentage Hydrologic Soil Group B =0.0%percent 6.00 3,287 6.00 0.24 Percentage Hydrologic Soil Groups C/D =100.0%percent 6.40 381 6.40 0.25 Target WQCV Drain Time =40.0 hours User Input 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 =N/A 0.98 1.36 1.71 2.31 2.91 in CUHP Runoff Volume =0.059 0.136 0.215 0.293 0.436 0.581 acre-ft Inflow Hydrograph Volume =N/A 0.136 0.215 0.293 0.436 0.581 acre-ft Time to Drain 97% of Inflow Volume =42.0 43.1 45.0 47.7 52.9 58.3 hours Time to Drain 99% of Inflow Volume =55.2 56.2 58.2 60.8 66.1 71.4 hours Maximum Ponding Depth =0.61 1.22 1.86 2.42 3.44 4.30 ft Maximum Ponded Area =0.10 0.11 0.13 0.13 0.15 0.16 acres Maximum Volume Stored =0.060 0.121 0.196 0.271 0.410 0.551 acre-ft Once CUHP has been run and the Stage-Area-Discharge information has been provided, click 'Process Data' to interpolate the Stage-Area-Volume-Discharge data and generate summary results in the table below. Once this is complete, click 'Print to PDF'. Stormwater Detention and Infiltration Design Data Sheet Worthington Storage - Detention Area 1 Fort Collins, CO SDI-Design Data v2.00, Released January 2020 Location for 1-hr Rainfall Depths (use dropdown): After providing required inputs above including 1-hour rainfall depths, click 'Run CUHP' to generate runoff hydrographs using the embedded Colorado Urban Hydrograph Procedure. Detention 1_SDI_Design_Data_v2.00 (State Compliance Time).xlsm, Design Data 3/8/2023, 3:42 AM Booleans for Message Booleans for CUHP Watershed L:W 1 CUHP Inputs Complete Watershed Lc:L 1 CUHP Results Calculated Watershed Slope FALSE Time Interval RunOnce 1 CountA 1 Draintime Coeff 1.0 User Precip 1 Equal SA Inputs 1 Equal SD Inputs 1 Stormwater Detention and Infiltration Design Data Sheet 0 2 4 6 8 10 12 14 0.1 1 10FLOW [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 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 0.1 1 10 100PONDING DEPTH [ft]DRAIN TIME [hr] 100YR 50YR 10YR 5YR 2YR WQCV Detention 1_SDI_Design_Data_v2.00 (State Compliance Time).xlsm, Design Data 3/8/2023, 3:42 AM NNORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: TIMBER LARK RESIDENTIAL FORT COLLINS | GREELEY APPENDIX DETENTION AREA 2 Date:03/07/23 Pond No.: 2 100-yr WQCV 0 ft3 0.87 Quantity Detention 36226 ft3 4.18 acres Total Volume 36226 ft3 1.66 cfs Total Volume 0.832 ac-ft Time Time Ft.Collins 100-yr Intensity Q100 Inflow (Runoff) Volume Outflow (Release) Volume Storage Detention Volume (mins)(secs)(in/hr)(cfs)(ft3)(ft3)(ft3) 5 300 9.95 36.2 10855 498 10357 10 600 7.72 28.1 16845 996 15849 15 900 6.52 23.7 21340 1494 19846 20 1200 5.60 20.4 24438 1992 22446 25 1500 4.98 18.1 27165 2490 24675 30 1800 4.52 16.4 29587 2988 26599 35 2100 4.08 14.8 31158 3486 27672 40 2400 3.74 13.6 32642 3984 28658 45 2700 3.46 12.6 33973 4482 29491 50 3000 3.23 11.7 35239 4980 30259 55 3300 3.03 11.0 36362 5478 30884 60 3600 2.86 10.4 37442 5976 31466 65 3900 2.72 9.9 38577 6474 32103 70 4200 2.59 9.4 39559 6972 32587 75 4500 2.48 9.0 40584 7470 33114 80 4800 2.38 8.7 41545 7968 33577 85 5100 2.29 8.3 42472 8466 34006 90 5400 2.21 8.0 43399 8964 34435 95 5700 2.13 7.7 44152 9462 34690 100 6000 2.06 7.5 44948 9960 34988 105 6300 2.00 7.3 45821 10458 35363 110 6600 1.94 7.1 46563 10956 35607 115 6900 1.89 6.9 47425 11454 35971 120 7200 1.84 6.7 48178 11952 36226 Detention Pond Calculation | FAA Method Project: Project Location: Calculations By: Worthington Storage Fort Collins, Colorado M. Ruebel Detention Area 2 Developed "C" = Area (A)= Max Release Rate = Input Variables Results Design Point Required Detention Volume Design Storm 1 Project Name Date 3/7/2023 City/County State CO Designed By MCR Primary Unit HD Double+Mini Base Material Stone XD Stack 1 Base Thickness 6 in Backfill Material Stone Secondary Unit XD Stack 60 Primary Unit Invert 5046.35 Treatment Row Unit Top Backfill Thickness 12 in Load Rating HS-20 Secondary Unit Invert 100.00 Finished Surface Type Asphalt Top Backfill Thickness 12 in R-Unit Footprint 4,458.00 sf Access Unit Invert 100.00 R-Unit Units 1447.92 Top Backfill Thickness 12 in R-Unit Perimeter 325.00 ft. Use Stone Storage Yes R-Unit Footprint Use Stone Base for Storage Yes R-Unit Units 0.00 Use Stone Cover for Storage Yes Stone Void Ratio 40% Excavation Footprint 5,124.00 sf Excavation Perimeter 341.00 ft.Treatment Unit Footprint 00.00 sf R-Unit Units 0.00 Treatment Unit Perimeter 00.00 ft. Geogrid Footprint 5,788.29 sf Geogrid Material ACF BX-12 # of Maintenance Ports 4 # of Inspection Ports 0 Material N080 Non-Woven Geotextile Optional Bottom Yes Material N080 Non-Woven Geotextile Location Top Yes Top Bottom Yes Bottom Sides Yes Sides Secondary Elevations 30 mil. PVCGeotextile Excavation Wrap Liner Liner Material Geotextile Unit Wrap Treatment Row Port Quantities Loading Criteria Primary Units Primary Elevations Treatment Row Units Secondary Units (Duel Height System) Access Unit Elevations R-TANK SUBSURFACE STORAGE SYSTEM DESIGN TOOL R-Unit Inputs Base and Top Backfill Material Worthington Storage - R-TANK BASIN 2 Fort Collins Total R-Unit Footprint and Perimeter Secondary R-Unit Footprint Excavation Footprint and Perimeter Geogrid Footprint Stone Storage Page 1 of 3 Project Name Worthington Storage - R-TANK BASIN 2 Date 3/7/2023 Location Fort Collins, CO Designed By MCR Unit Inv.Unit Top Top Stone Min. Grade Max Grade 5046.35 5049.89 5050.89 5051.56 5056.88 Storage Capcacity Detention Area 2 Desired Storage Volume Total Volume Provided in R-Unit: Total Volume Provided in Stone: Provided Storage Volume: Elev.Volume Additional Units Req. Number of Primary Units: Number of Secondary Units: # of Maintenance Ports: Number of Access Units: # of Inspection Ports: Required Backfill Material: Estimated Geotextile Unit Wrap:(1286 sy) Estimated Geotextile Excavation Wrap:(1529 sy) Estimated Liner:(0 sy) Estimated Geogrid:(740 sy) Estimated Treatment Row Wrap:(0 sy) Estimated Treatment Row Base Fabric:(0 sy) Treatment Units 27 Input Elev. Output Vol. Full Storage 0 19,372 cf Full Storage Capacity Stage Volume Capacity System Quantities Difference = 1,448 Primary Units 19,024.72 cf 4,018.34 cf 15,006.37 cf System Storage Capacities Base Inv. 5,045.85 Secondary Units 0 sf System Elevations R-TANK SUBSURFACE STORAGE SYSTEM DESIGN TOOL Elevations 6,657 sf 0 sf 4 0 sf 11,578 sf 13,763 sf 0 0 372 cy Page 2 of 3 Project Name Worthington Storage - R-TANK BASIN 2 Date 3/7/2023 Location Fort Collins, CO Designed By MCR Total Volume Provided in R-Unit: Total Volume Provided in Stone: Provided Storage Volume: Stage Storage Increment 0.50 ft Elevation Volume 5,045.85 0.00 5,046.35 1,024.80 5,046.85 3,275.55 5,047.35 5,526.30 5,047.85 7,777.05 5,048.35 10,027.80 5,048.85 12,278.55 5,049.35 14,529.30 5,049.85 16,780.05 5,050.35 16,975.11 5,050.85 18,935.90 5,050.89 19,024.71 R-Unit Stage Storage Table R-TANK SUBSURFACE STORAGE SYSTEM DESIGN TOOL System Storage Capacities 15,006.37 cf 4,018.34 cf 19,024.72 cf Page 3 of 3 Project Name Date 3/7/2023 City/County State CO Designed By JKB Primary Unit HD Double Base Material Stone XD Stack 1 Base Thickness 6 in Backfill Material Stone Secondary Unit XD Stack 60 Primary Unit Invert 5047.80 Treatment Row Unit Top Backfill Thickness 12 in Load Rating HS-20 Secondary Unit Invert 100.00 Finished Surface Type Asphalt Top Backfill Thickness 12 in R-Unit Footprint 3,069.00 sf Access Unit Invert 100.00 R-Unit Units 996.78 Top Backfill Thickness 12 in R-Unit Perimeter 317.00 ft. Use Stone Storage Yes R-Unit Footprint Use Stone Base for Storage Yes R-Unit Units 0.00 Use Stone Cover for Storage Yes Stone Void Ratio 40% Excavation Footprint 3,721.00 sf Excavation Perimeter 334.00 ft.Treatment Unit Footprint 00.00 sf R-Unit Units 0.00 Treatment Unit Perimeter 00.00 ft. Geogrid Footprint 3,484.65 sf Geogrid Material ACF BX-12 # of Maintenance Ports 4 # of Inspection Ports 0 Material N080 Non-Woven Geotextile Optional Bottom Yes Material N080 Non-Woven Geotextile Location Top Yes Top Bottom Yes Bottom Sides Yes Sides Total R-Unit Footprint and Perimeter Secondary R-Unit Footprint Excavation Footprint and Perimeter Geogrid Footprint Stone Storage Access Unit Elevations R-TANK SUBSURFACE STORAGE SYSTEM DESIGN TOOL R-Unit Inputs Base and Top Backfill Material Worthington Storage - R-TANK BASIN 3 Fort Collins Loading Criteria Primary Units Primary Elevations Treatment Row Units Secondary Units (Duel Height System) Geotextile Excavation Wrap Liner Liner Material Geotextile Unit Wrap Treatment Row Port Quantities Secondary Elevations 30 mil. PVC Page 1 of 3 Project Name Worthington Storage - R-TANK BASIN 3 Date 3/7/2023 Location Fort Collins, CO Designed By JKB Unit Inv.Unit Top Top Stone Min. Grade Max Grade 5047.80 5050.62 5051.62 5052.29 5057.61 Storage Capcacity Detention Area 2 Desired Storage Volume Total Volume Provided in R-Unit: Total Volume Provided in Stone: Provided Storage Volume: Elev.Volume Additional Units Req. Number of Primary Units: Number of Secondary Units: # of Maintenance Ports: Number of Access Units: # of Inspection Ports: Required Backfill Material: Estimated Geotextile Unit Wrap:(899 sy) Estimated Geotextile Excavation Wrap:(1135 sy) Estimated Liner:(0 sy) Estimated Geogrid:(445 sy) Estimated Treatment Row Wrap:(0 sy) Estimated Treatment Row Base Fabric:(0 sy) 4,007 sf 0 sf 4 0 sf 8,087 sf 10,218 sf 0 0 275 cy Secondary Units 0 sf System Elevations R-TANK SUBSURFACE STORAGE SYSTEM DESIGN TOOL Elevations Primary Units 11,195.20 cf 2,968.49 cf 8,226.71 cf System Storage Capacities Base Inv. 5,047.30 System Quantities Difference = 997 Treatment Units 31 Input Elev. Output Vol. Full Storage 0 11,543 cf Full Storage Capacity Stage Volume Capacity Page 2 of 3 Project Name Worthington Storage - R-TANK BASIN 3 Date 3/7/2023 Location Fort Collins, CO Designed By JKB Total Volume Provided in R-Unit: Total Volume Provided in Stone: Provided Storage Volume: Stage Storage Increment 0.50 ft Elevation Volume 5,047.30 0.00 5,047.80 744.20 5,048.30 2,332.38 5,048.80 3,920.55 5,049.30 5,508.73 5,049.80 7,096.90 5,050.30 8,685.08 5,050.80 9,706.80 5,051.30 10,716.43 5,051.62 11,195.20 R-TANK SUBSURFACE STORAGE SYSTEM DESIGN TOOL System Storage Capacities 8,226.71 cf 2,968.49 cf 11,195.20 cf R-Unit Stage Storage Table Page 3 of 3 User Inputs Chamber Model: MC-3500 Outlet Control Structure: Yes Project Name: Stormtech Basin 3 Engineer: Mason undefined Project Location: Colorado Measurement Type: Imperial Required Storage Volume: 6500 cubic ft. Stone Porosity: 40% Stone Foundation Depth: 9 in. Stone Above Chambers: 12 in. Average Cover Over Chambers: 18 in. Design Constraint Dimensions:(20 ft. x 160 ft.) Results System Volume and Bed Size Installed Storage Volume: 6703.29 cubic ft. Storage Volume Per Chamber: 109.90 cubic ft. Number Of Chambers Required: 33 Number Of End Caps Required: 4 Chamber Rows: 2 Maximum Length:131.51 ft. Maximum Width: 15.93 ft. Approx. Bed Size Required: 2041.60 square ft. System Components Amount Of Stone Required: 280 cubic yards Volume Of Excavation (Not Including Fill): 416 cubic yards Total Non-woven Geotextile Required:761 square yards Woven Geotextile Required (excluding Isolator Row): 17 square yards Woven Geotextile Required (Isolator Row): 147 square yards Total Woven Geotextile Required:164 square yards Impervious Liner Required:0 square yards Project Number: Project Name: Project Location: Pond No:Calc. By:M. Ruebel Orifice Dia (in):4 13/16 Orifice Area (sf):0.13 Orifice invert (ft):5,045.51 Orifice Coefficient:0.65 Elevation Stage (ft)Velocity (ft/s)Flow Rate (cfs)Comments 5,045.51 0.00 0.00 0.00 5,046.01 0.50 3.69 0.47 5,046.51 1.00 5.21 0.66 5,047.01 1.50 6.39 0.81 5,047.51 2.00 7.37 0.94 5,048.01 2.50 8.24 1.05 5,048.51 3.00 9.03 1.15 5,049.01 3.50 9.75 1.24 5,049.51 4.00 10.43 1.33 5,050.01 4.50 11.06 1.41 5,050.51 5.00 11.66 1.48 5,050.75 5.24 11.93 1.52 5,051.01 5.50 12.23 1.56 Top of R-Tank Basin 2 5,051.25 5.74 12.49 1.59 Top of Stormtech Basin 5 5,051.51 6.00 12.77 1.62 5,051.62 6.11 12.89 1.64 100-Year Storm/R-Tank Basin 3 Orifice Rating Curve ORIFICE RATING CURVE 1853-001 Worthington Storage Fort Collins Detention Area 2 Orifice Design Data Detention Area 2 NORTHERNENGINEERING.COM | 970.221.4158 FORT COLLINS | GREELEY Stormwater Facility Name: Facility Location & Jurisdiction: User Input: Watershed Characteristics User Defined User Defined User Defined User Defined Selected BMP Type =EDB Stage [ft]Area [ft^2]Stage [ft]Discharge [cfs] Watershed Area =4.18 acres 0.00 5,161 0.00 0.00 Watershed Length =550 ft 1.00 5,161 1.00 0.71 Watershed Length to Centroid =200 ft 2.00 8,521 2.00 1.01 Watershed Slope =0.020 ft/ft 3.00 9,024 3.00 1.23 Watershed Imperviousness =63.0%percent 4.00 9,024 4.00 1.42 Percentage Hydrologic Soil Group A =0.0%percent 5.00 4,766 5.00 1.59 Percentage Hydrologic Soil Group B =0.0%percent 5.40 1,118 5.40 1.65 Percentage Hydrologic Soil Groups C/D =100.0%percent Target WQCV Drain Time =40.0 hours User Input 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 =N/A 0.98 1.36 1.71 2.31 2.91 in CUHP Runoff Volume =0.086 0.197 0.315 0.432 0.646 0.863 acre-ft Inflow Hydrograph Volume =N/A 0.197 0.315 0.432 0.646 0.863 acre-ft Time to Drain 97% of Inflow Volume =7.2 8.0 8.4 9.0 10.3 11.4 hours Time to Drain 99% of Inflow Volume =9.4 10.2 10.7 11.3 12.4 13.7 hours Maximum Ponding Depth =0.73 1.02 1.62 2.12 3.09 4.05 ft Maximum Ponded Area =0.12 0.12 0.17 0.20 0.21 0.20 acres Maximum Volume Stored =0.086 0.121 0.207 0.298 0.495 0.694 acre-ft Once CUHP has been run and the Stage-Area-Discharge information has been provided, click 'Process Data' to interpolate the Stage-Area-Volume-Discharge data and generate summary results in the table below. Once this is complete, click 'Print to PDF'. Stormwater Detention and Infiltration Design Data Sheet Worthington Storage - Detention Area 2 Fort Collins, CO SDI-Design Data v2.00, Released January 2020 Location for 1-hr Rainfall Depths (use dropdown): After providing required inputs above including 1-hour rainfall depths, click 'Run CUHP' to generate runoff hydrographs using the embedded Colorado Urban Hydrograph Procedure. Detention 2_SDI_Design_Data_v2.00 (State Compliance Time).xlsm, Design Data 3/8/2023, 3:40 AM Booleans for Message Booleans for CUHP Watershed L:W 1 CUHP Inputs Complete Watershed Lc:L 1 CUHP Results Calculated Watershed Slope FALSE Time Interval RunOnce 1 CountA 1 Draintime Coeff 1.0 User Precip 1 Equal SA Inputs 1 Equal SD Inputs 1 Stormwater Detention and Infiltration Design Data Sheet 0 2 4 6 8 10 12 14 16 18 20 0.1 1 10FLOW [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 0.5 1 1.5 2 2.5 3 3.5 4 4.5 0.1 1 10 100PONDING DEPTH [ft]DRAIN TIME [hr] 100YR 50YR 10YR 5YR 2YR WQCV Detention 2_SDI_Design_Data_v2.00 (State Compliance Time).xlsm, Design Data 3/8/2023, 3:40 AM NNORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: TIMBER LARK RESIDENTIAL FORT COLLINS | GREELEY APPENDIX LID CALCULATIONS SSSCVAULTELECSSSELECCELECEDDTCONTROLIRRGXXVAULTF.O.XXXXSSSCVAULTELECSSSELECCELECEDDTCONTROLIRRGXXVAULTF.O.DRAWN BY:SCALE:DATE:EXISTING VS PROPOSEDIMPERVIOUS AREASHEET NO:FORT COLLINS: 301 North Howes Street, Suite 100, 80521GREELEY: 820 8th Street, 80631ENGINEERNGIEHTRONRN970.221.4158northernengineering.comP:\1853-001\DWG\DRNG\1853-001_IMPV.DWG 2525 WORTHINGTON MINI-STORAGEFORT COLLINSCOLORADOMCREXISTINGPROPOSED( IN FEET )01 INCH = 60 FEET6060ROOFTOPCONCRETEASPHALTSURFACEAREA (SF)% IMPERV.IMPERV.AREA (SF)19,2207,17986,223100%100%100%112,622TOTAL=19,2207,17986,223GRAVEL040%01" = 60'5/18/2022IMP 1LANDSCAPING27,0230%0ROOFTOPCONCRETEASPHALTSURFACEAREA (SF)% IMPERV.IMPERV.AREA (SF)52,9838,35249,971100%100%100%111,306TOTAL=52,9838,35249,971GRAVEL040%0LANDSCAPING28,3390%0WO R T H I N G T O N C I R C L E WO R T H I N G T O N C I R C L E TFUD UD UDUDUDUDUDUD EUD UD XXXCVAULTELECELECCELECEDDDTCONTROLIRRGXVAULTF.O.a1b2b1OS3OS1OS21.93 ac.OS11.57 ac.OS20.31 ac.A21.47 ac.B11.14 ac.B20.33 ac.OS30.23 ac.A1a2R-TANKBASIN 2R-TANKBASIN 1STORMTECHBASIN 1STORMTECHBASIN 2R-TANKBASIN 1STORMTECHBASIN 4STORMTECHBASIN 3STORMTECHBASIN 5R-TANKBASIN 3DRAWN BY:SCALE:DATE:WQ EXHIBITSHEET NO:FORT COLLINS: 301 North Howes Street, Suite 100, 80521GREELEY: 820 8th Street, 80631ENGINEERNGIEHTRONRN970.221.4158northernengineering.comP:\1853-001\DWG\DRNG\1853-001_LID.DWG WORTHINGTON ENCLOSED MINI-STORAGEFORT COLLINSCOLORADOMCR1" = 70'12/21/2022LID 1W O R T H I N G T O N C I R C L E PROPOSED STORM SEWERPROPOSED CURB & GUTTERPROPERTY BOUNDARYPROPOSED INLETADESIGN POINTDRAINAGE BASIN LABELDRAINAGE BASIN BOUNDARYALEGEND:FOR DRAINAGE REVIEW ONLYNOT FOR CONSTRUCTION( IN FEET )1 inch = ft.Feet0707070LOT 1LOT 2PROPOSED BASINw/ WQ WEIRPROPOSED BOXw/ WQ WEIRPROPOSEDWATER QUALITYSTRUCTUREPROPOSED BASINw/ WQ WEIRR-TANK STORMWATER MODULESMC-3500 STORMTECH CHAMBERS(ISOLATOR ROW)Water Quality Treatment SummaryBasinWQCV(ft3)SummaryA1 & OS34083 - MC-3500 (Stormtech Basin 1)A2 & OS1207914 - MC-3500 (Stormtech Basin 2)B1 & OS2236716 - MC-3500 (Stormtech Basin 4)B214109 - MC-3500 (Stormtech Basin 3)LID Site Summary - Onsite Total SiteTotal On-Site Area137,538ft2Total On-Site Impervious Area106,054ft2Total Onsite Impervious Area without LID Treatment0ft2Total Onsite Treated Area106,054ft2Percent On-site Impervious Treated by LID100.00%Detention SummaryBasinVolume (cuft)R-Tank Basin 130,138R-Tank Basin 219,024R-Tank Basin 311,195Stormtech Basin 56,703Total67,060 Vault ID Total Required WQ Volume (cf) Flow, WQ (cfs) Chamber Type Chamber Release Ratea (cfs) Chamber Volumeb (cf) Installed Chamber w/ Aggregatec (cf) Minimum No. of Chambersd Total Release Ratee (cfs) Required Storage Volume by FAA Method (cf) Mimimum No. of Chambersf Provided Number of Chambers Provided Release Rate (cfs) Storage Provided within the Chambersg (cf) Total Installed System Volumeh (cf) Isolator Row A1 & OS3 408 0.45 MC-3500 0.038 109.90 175.00 3 0.11 269 3 3 0.11 330 525 a. Release rate per chamber, limited by flow through geotextile with accumulated sediment. Q=0.0022(cfs/sf)*(Floor Area of Chamber) *Flow rate based on 1/2 of Nov 07 Q MAX in Figure 17 of UNH Testing Report b. Volume within chamber only, not accounting for void spaces in surrounding aggregate. c. Volume includes chamber and void spaces (40%) in surrounding aggregate, per chamber unit. d. Number of chambers required to provide full WQCV within total installed system, including aggregate. e. Release rate per chamber times number of chambers. f. Number of chambers required to provide required FAA storage volume stored within the chamber only (no aggregate storage). g. Volume provided in chambers only (no aggregate storage). This number must meet or exceed the required FAA storage volume. h. System volume includes total number of chambers, plus surrounding aggregate. This number must meet or exceed the required WQCV. Chamber Configuration Summary P:\1853-001\Drainage\LID\Final\1853-001 Chamber Summary_A1_OS3.xlsx STORMTECH BASIN 1 Project Title Date: Project Number Calcs By: City Basins 0.8 WQCV = Watershed inches of Runoff (inches)51% a = Runoff Volume Reduction (constant) i = Total imperviousness Ratio (i = Iwq/100)0.167 in A =0.56 ac V = 0.0078 ac-ft V = Water Quality Design Volume (ac-ft) WQCV = Water Quality Capture Volume (inches) A = Watershed Area (acres) Worthington Storage March 7, 2023 1853-001 M. Ruebel Fort Collins A1 & OS3 408 cu. ft. Drain Time a = i = WQCV = Figure EDB-2 - Water Quality Capture Volume (WQCV), 80th Percentile Runoff Event 0.231 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5 00.10.20.30.40.50.60.70.80.91WQCV (watershed inches)Total Imperviousness Ratio (i = Iwq/100) Water Quality Capture Volume 6 hr 12 hr 24 hr 40 hr ()iii78.019.10.91aWQCV 23 +−= ()iii78.019.10.91aWQCV 23 +−= AV*12 WQCV   = 12 hr STORMTECH BASIN 1 Pond No : A1 &OS3 WQ 0.58 5.00 min 269 ft3 0.56 acres 0.01 ac-ft Max Release Rate =0.11 cfs Time (min) Ft Collins WQ Intensity (in/hr) Inflow Volume (ft3) Outflow Adjustment Factor QWQ (cfs) Outflow Volume (ft3) Storage Volume (ft3) 5 1.425 139 1.00 0.11 33 106 10 1.105 215 1.00 0.11 66 149 15 0.935 273 0.67 0.07 66 207 20 0.805 314 0.63 0.07 83 231 25 0.715 348 0.60 0.07 99 249 30 0.650 380 0.58 0.06 116 265 35 0.585 399 0.57 0.06 132 267 40 0.535 417 0.56 0.06 149 269 45 0.495 434 0.56 0.06 165 269 50 0.460 448 0.55 0.06 182 267 55 0.435 466 0.55 0.06 198 268 60 0.410 479 0.54 0.06 215 265 65 0.385 488 0.54 0.06 231 257 70 0.365 498 0.54 0.06 248 250 75 0.345 504 0.53 0.06 264 240 80 0.330 514 0.53 0.06 281 234 85 0.315 522 0.53 0.06 297 225 90 0.305 535 0.53 0.06 314 221 95 0.290 537 0.53 0.06 330 207 100 0.280 546 0.53 0.06 347 199 105 0.270 552 0.52 0.06 363 189 110 0.260 557 0.52 0.06 380 178 115 0.255 571 0.52 0.06 396 175 120 0.245 573 0.52 0.06 413 160 *Note: Using the method described in FCSCM Chapter 6 Section 2.3 DETENTION POND CALCULATION; MODIFIED FAA METHOD w/ Ft Collins IDF Input Variables Results Required Detention Volume Fort Collins, Colorado 1853-001 Worthington Storage Project Number : Project Name : Isolator Row A1 & OS3 A = Tc = Project Location : Design Point C = Design Storm Page 1 of 1 1853-001 Chamber Summary_A1_OS3.xlsx STORMTECH BASIN 1 Project Number:Pond No: Project Name:Calc. By: Project Location: Q=3.3LH1.5 Length (L)=2.00 ft 5,051.88 ft Weir Elev. =5,049.42 ft 5,046.77 ft Depth Above Crest - H (ft) Elevation (ft) Freeboard (ft) Flow (cfs) 0.00 5,049.42 2.46 0.00 0.15 5,049.57 2.31 0.38 0.30 5,049.72 2.16 1.08 0.45 5,049.87 2.01 1.99 0.60 5,050.02 1.86 3.07 0.72 5,050.14 1.74 4.03 0.75 5,050.17 1.71 4.29 0.90 5,050.32 1.56 5.64 1.00 5,050.42 1.46 6.60 1.10 5,050.52 1.36 7.61 1.20 5,050.62 1.26 8.68 1.30 5,050.72 1.16 9.78 2.46 5,051.88 0.00 25.47 Rim of Basin 100-Year Storm SHARP-CRESTED WEIR 1853-001 Stormtech Basin 1 Worthington Storage M. Ruebel 100-Year Storm = 4.0 cfs LID Weir in Basin D2 Input Parameters: Basin Rim Elev. = Basin Invert Elev. = Depth vs. Flow: Governing Equations: This equation can be used to derive the stage-discharge relationship for a sharp crested weir where the depth of flow is small compared to the length of weir. Reference 1) Hydrologic Analysis and Design, Richard H McCuen, Prentice Hall, 1989. Pg.549. Fort Collins, Colorado * where Q is flow rate in CFS * where L is the crest length of the weir (FT) * where H is the height of flow over the crest (FT) Notes NORTHERNENGINEERING.COM | 970.221.4158 FORT COLLINS | GREELEY STORMTECH BASIN 1 Vault ID Total Required WQ Volume (cf) Flow, WQ (cfs) Chamber Type Chamber Release Ratea (cfs) Chamber Volumeb (cf) Installed Chamber w/ Aggregatec (cf) Minimum No. of Chambersd Total Release Ratee (cfs) Required Storage Volume by FAA Method (cf) Mimimum No. of Chambersf Provided Number of Chambers Provided Release Rate (cfs) Storage Provided within the Chambersg (cf) Total Installed System Volumeh (cf) Isolator Row A2 & OS1 2079 0.35 MC-3500 0.038 109.90 175.00 12 0.45 1361 13 14 0.53 1539 2450 a. Release rate per chamber, limited by flow through geotextile with accumulated sediment. Q=0.0022(cfs/sf)*(Floor Area of Chamber) *Flow rate based on 1/2 of Nov 07 Q MAX in Figure 17 of UNH Testing Report b. Volume within chamber only, not accounting for void spaces in surrounding aggregate. c. Volume includes chamber and void spaces (40%) in surrounding aggregate, per chamber unit. d. Number of chambers required to provide full WQCV within total installed system, including aggregate. e. Release rate per chamber times number of chambers. f. Number of chambers required to provide required FAA storage volume stored within the chamber only (no aggregate storage). g. Volume provided in chambers only (no aggregate storage). This number must meet or exceed the required FAA storage volume. h. System volume includes total number of chambers, plus surrounding aggregate. This number must meet or exceed the required WQCV. Chamber Configuration Summary P:\1853-001\Drainage\LID\Final\1853-001 Chamber Summary_A2_OS1.xlsx STORMTECH BASIN 2 Project Title Date: Project Number Calcs By: City Basins 0.8 WQCV = Watershed inches of Runoff (inches)68% a = Runoff Volume Reduction (constant) i = Total imperviousness Ratio (i = Iwq/100)0.213 in A =2.24 ac V = 0.0398 ac-ft V = Water Quality Design Volume (ac-ft) WQCV = Water Quality Capture Volume (inches) A = Watershed Area (acres) 2079 cu. ft. Drain Time a = i = WQCV = Figure EDB-2 - Water Quality Capture Volume (WQCV), 80th Percentile Runoff Event Worthington Storage March 7, 2023 1853-001 M. Ruebel Fort Collins A2&OS1 0.231 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5 00.10.20.30.40.50.60.70.80.91WQCV (watershed inches)Total Imperviousness Ratio (i = Iwq/100) Water Quality Capture Volume 6 hr 12 hr 24 hr 40 hr ()iii78.019.10.91aWQCV 23 +−= ()iii78.019.10.91aWQCV 23 +−= AV*12 WQCV   = 12 hr STORMTECH BASIN 2 Pond No : A2&OS1 WQ 0.72 5.00 min 1361 ft3 2.24 acres 0.03 ac-ft Max Release Rate =0.53 cfs Time (min) Ft Collins WQ Intensity (in/hr) Inflow Volume (ft3) Outflow Adjustment Factor QWQ (cfs) Outflow Volume (ft3) Storage Volume (ft3) 5 1.425 689 1.00 0.53 159 530 10 1.105 1069 1.00 0.53 318 751 15 0.935 1357 0.67 0.35 318 1039 20 0.805 1558 0.63 0.33 398 1160 25 0.715 1730 0.60 0.32 477 1253 30 0.650 1887 0.58 0.31 557 1330 35 0.585 1981 0.57 0.30 636 1345 40 0.535 2071 0.56 0.30 716 1355 45 0.495 2156 0.56 0.29 795 1361 50 0.460 2226 0.55 0.29 875 1351 55 0.435 2315 0.55 0.29 954 1361 60 0.410 2380 0.54 0.29 1034 1347 65 0.385 2422 0.54 0.29 1113 1309 70 0.365 2472 0.54 0.28 1193 1280 75 0.345 2504 0.53 0.28 1272 1232 80 0.330 2555 0.53 0.28 1352 1203 85 0.315 2591 0.53 0.28 1431 1160 90 0.305 2656 0.53 0.28 1511 1146 95 0.290 2666 0.53 0.28 1590 1076 100 0.280 2710 0.53 0.28 1670 1040 105 0.270 2743 0.52 0.28 1749 994 110 0.260 2768 0.52 0.28 1829 939 115 0.255 2838 0.52 0.28 1908 930 120 0.245 2845 0.52 0.28 1988 857 *Note: Using the method described in FCSCM Chapter 6 Section 2.3 A = Tc = Project Location : Design Point C = Design Storm DETENTION POND CALCULATION; MODIFIED FAA METHOD w/ Ft Collins IDF Input Variables Results Required Detention Volume Fort Collins, Colorado 1853-001 Worthington Storage Project Number : Project Name : Isolator Row A2&OS1 Page 1 of 1 1853-001 Chamber Summary_A2_OS1.xlsx STORMTECH BASIN 2 Project Number:Pond No: Project Name:Calc. By: Project Location: Q=3.3LH1.5 Length (L)=4.00 ft 5,051.98 ft Weir Elev. =5,049.73 ft 5,046.09 ft Depth Above Crest - H (ft) Elevation (ft) Freeboard (ft) Flow (cfs) 0.00 5,049.73 2.25 0.00 0.25 5,049.98 2.00 1.65 0.50 5,050.23 1.75 4.67 0.75 5,050.48 1.50 8.57 1.00 5,050.73 1.25 13.20 1.25 5,050.98 1.00 18.45 1.50 5,051.23 0.75 24.25 1.75 5,051.48 0.50 30.56 2.00 5,051.73 0.25 37.34 2.10 5,051.83 0.15 40.17 2.20 5,051.93 0.05 43.07 2.30 5,052.03 -0.05 46.04 2.25 5,051.98 0.00 44.55 100-Year Storm = 20.0 cfs LID Weir in Basin C2 Input Parameters: Basin Rim Elev. = Depth vs. Flow: Governing Equations: This equation can be used to derive the stage-discharge relationship for a sharp crested weir where the depth of flow is small compared to the length of weir. Reference 1) Hydrologic Analysis and Design, Richard H McCuen, Prentice Hall, 1989. Pg.549. Fort Collins, Colorado * where Q is flow rate in CFS * where L is the crest length of the weir (FT) * where H is the height of flow over the crest (FT) Notes Basin Invert Elev. = SHARP-CRESTED WEIR 1853-001 Stormtech Basin 2 Worthington Storage M. Ruebel Rim of Basin 100-Year Storm NORTHERNENGINEERING.COM | 970.221.4158 FORT COLLINS | GREELEY STORMTECH BASIN 2 Vault ID Total Required WQ Volume (cf) Flow, WQ (cfs) Chamber Type Chamber Release Ratea (cfs) Chamber Volumeb (cf) Installed Chamber w/ Aggregatec (cf) Minimum No. of Chambersd Total Release Ratee (cfs) Required Storage Volume by FAA Method (cf) Mimimum No. of Chambersf Provided Number of Chambers Provided Release Rate (cfs) Storage Provided within the Chambersg (cf) Total Installed System Volumeh (cf) Isolator Row B2 1410 0.45 MC-3500 0.038 109.90 175.00 9 0.34 816 8 9 0.34 989 1575 a. Release rate per chamber, limited by flow through geotextile with accumulated sediment. Q=0.0022(cfs/sf)*(Floor Area of Chamber) *Flow rate based on 1/2 of Nov 07 Q MAX in Figure 17 of UNH Testing Report b. Volume within chamber only, not accounting for void spaces in surrounding aggregate. c. Volume includes chamber and void spaces (40%) in surrounding aggregate, per chamber unit. d. Number of chambers required to provide full WQCV within total installed system, including aggregate. e. Release rate per chamber times number of chambers. f. Number of chambers required to provide required FAA storage volume stored within the chamber only (no aggregate storage). g. Volume provided in chambers only (no aggregate storage). This number must meet or exceed the required FAA storage volume. h. System volume includes total number of chambers, plus surrounding aggregate. This number must meet or exceed the required WQCV. Chamber Configuration Summary P:\1853-001\Drainage\LID\Final\1853-001 Chamber Summary_B2.xlsx STORMTECH BASIN 3 Project Title Date: Project Number Calcs By: City Basins 0.8 WQCV = Watershed inches of Runoff (inches)84% a = Runoff Volume Reduction (constant) i = Total imperviousness Ratio (i = Iwq/100)0.284 in A =1.14 ac V = 0.0270 ac-ft V = Water Quality Design Volume (ac-ft) WQCV = Water Quality Capture Volume (inches) A = Watershed Area (acres) 1410 cu. ft. Drain Time a = i = WQCV = Figure EDB-2 - Water Quality Capture Volume (WQCV), 80th Percentile Runoff Event Worthington Storage March 7, 2023 1853-001 M. Ruebel Fort Collins B2 0.231 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5 00.10.20.30.40.50.60.70.80.91WQCV (watershed inches)Total Imperviousness Ratio (i = Iwq/100) Water Quality Capture Volume 6 hr 12 hr 24 hr 40 hr ()iii78.019.10.91aWQCV 23 +−= ()iii78.019.10.91aWQCV 23 +−= AV*12 WQCV   = 12 hr STORMTECH BASIN 3 Pond No : B2 WQ 0.87 5.00 min 816 ft3 1.14 acres 0.02 ac-ft Max Release Rate =0.34 cfs Time (min) Ft Collins WQ Intensity (in/hr) Inflow Volume (ft3) Outflow Adjustment Factor QWQ (cfs) Outflow Volume (ft3) Storage Volume (ft3) 5 1.425 424 1.00 0.34 102 322 10 1.105 658 1.00 0.34 204 454 15 0.935 835 0.67 0.23 204 631 20 0.805 958 0.63 0.21 255 703 25 0.715 1064 0.60 0.20 306 758 30 0.650 1160 0.58 0.20 357 803 35 0.585 1218 0.57 0.19 408 810 40 0.535 1273 0.56 0.19 459 814 45 0.495 1326 0.56 0.19 510 816 50 0.460 1369 0.55 0.19 561 808 55 0.435 1424 0.55 0.19 612 812 60 0.410 1464 0.54 0.18 663 801 65 0.385 1489 0.54 0.18 714 775 70 0.365 1520 0.54 0.18 765 755 75 0.345 1540 0.53 0.18 816 724 80 0.330 1571 0.53 0.18 867 704 85 0.315 1593 0.53 0.18 918 675 90 0.305 1633 0.53 0.18 969 664 95 0.290 1639 0.53 0.18 1020 619 100 0.280 1666 0.53 0.18 1071 595 105 0.270 1687 0.52 0.18 1122 565 110 0.260 1702 0.52 0.18 1173 529 115 0.255 1745 0.52 0.18 1224 521 120 0.245 1750 0.52 0.18 1275 475 *Note: Using the method described in FCSCM Chapter 6 Section 2.3 A = Tc = Project Location : Design Point C = Design Storm DETENTION POND CALCULATION; MODIFIED FAA METHOD w/ Ft Collins IDF Input Variables Results Required Detention Volume Fort Collins, Colorado 1853-001 Worthington Storage Project Number : Project Name : Isolator Row B2 Page 1 of 1 1853-001 Chamber Summary_B2.xlsx STORMTECH BASIN 3 Project Number:Pond No: Project Name:Calc. By: Project Location: Q=3.3LH1.5 Length (L)=4.00 ft 5,051.95 ft Weir Elev. =5,050.18 ft 5,046.41 ft Depth Above Crest - H (ft) Elevation (ft) Freeboard (ft) Flow (cfs) 0.00 5,050.18 1.77 0.00 0.25 5,050.43 1.52 1.65 0.50 5,050.68 1.27 4.67 0.75 5,050.93 1.02 8.57 1.00 5,051.18 0.77 13.20 1.25 5,051.43 0.52 18.45 1.44 5,051.62 0.33 22.81 1.50 5,051.68 0.27 24.25 1.75 5,051.93 0.02 30.56 2.00 5,052.18 -0.23 37.34 2.15 5,052.33 -0.38 41.61 2.30 5,052.48 -0.53 46.04 1.77 5,051.95 0.00 31.08 Basin Invert Elev. = Rim of Basin 100-Year Storm SHARP-CRESTED WEIR 1853-001 Stormtech Basin 3 Worthington Storage M. Ruebel 100-Year Storm = 11.4 cfs LID Weir in Basin E4 Input Parameters: Basin Rim Elev. = Depth vs. Flow: Governing Equations: This equation can be used to derive the stage-discharge relationship for a sharp crested weir where the depth of flow is small compared to the length of weir. Reference 1) Hydrologic Analysis and Design, Richard H McCuen, Prentice Hall, 1989. Pg.549. Fort Collins, Colorado * where Q is flow rate in CFS * where L is the crest length of the weir (FT) * where H is the height of flow over the crest (FT) Notes NORTHERNENGINEERING.COM | 970.221.4158 FORT COLLINS | GREELEY STORMTECH BASIN 3 Vault ID Total Required WQ Volume (cf) Flow, WQ (cfs) Chamber Type Chamber Release Ratea (cfs) Chamber Volumeb (cf) Installed Chamber w/ Aggregatec (cf) Minimum No. of Chambersd Total Release Ratee (cfs) Required Storage Volume by FAA Method (cf) Mimimum No. of Chambersf Provided Number of Chambers Provided Release Rate (cfs) Storage Provided within the Chambersg (cf) Total Installed System Volumeh (cf) Isolator Row B1&OS2 2367 2.50 MC-3500 0.038 109.90 175.00 14 0.53 1669 16 16 0.60 1758 2800 a. Release rate per chamber, limited by flow through geotextile with accumulated sediment. Q=0.0022(cfs/sf)*(Floor Area of Chamber) *Flow rate based on 1/2 of Nov 07 Q MAX in Figure 17 of UNH Testing Report b. Volume within chamber only, not accounting for void spaces in surrounding aggregate. c. Volume includes chamber and void spaces (40%) in surrounding aggregate, per chamber unit. d. Number of chambers required to provide full WQCV within total installed system, including aggregate. e. Release rate per chamber times number of chambers. f. Number of chambers required to provide required FAA storage volume stored within the chamber only (no aggregate storage). g. Volume provided in chambers only (no aggregate storage). This number must meet or exceed the required FAA storage volume. h. System volume includes total number of chambers, plus surrounding aggregate. This number must meet or exceed the required WQCV. Chamber Configuration Summary P:\1853-001\Drainage\LID\Final\1853-001 Chamber Summary_B1_OS2.xlsx STORMTECH BASIN 4 Project Title Date: Project Number Calcs By: City Basins 0.8 WQCV = Watershed inches of Runoff (inches)56% a = Runoff Volume Reduction (constant) i = Total imperviousness Ratio (i = Iwq/100)0.179 in A =3.04 ac V = 0.0453 ac-ft V = Water Quality Design Volume (ac-ft) WQCV = Water Quality Capture Volume (inches) A = Watershed Area (acres) Worthington Storage March 7, 2023 1853-001 M. Ruebel Fort Collins B1 & OS2 2367 cu. ft. Drain Time a = i = WQCV = Figure EDB-2 - Water Quality Capture Volume (WQCV), 80th Percentile Runoff Event 0.231 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5 00.10.20.30.40.50.60.70.80.91WQCV (watershed inches)Total Imperviousness Ratio (i = Iwq/100) Water Quality Capture Volume 6 hr 12 hr 24 hr 40 hr ()iii78.019.10.91aWQCV 23 +−= ()iii78.019.10.91aWQCV 23 +−= AV*12 WQCV   = 12 hr STORMTECH BASIN 4 Pond No : B1&OS2 WQ 0.63 5.00 min 1669 ft3 3.04 acres 0.04 ac-ft Max Release Rate =0.60 cfs Time (min) Ft Collins WQ Intensity (in/hr) Inflow Volume (ft3) Outflow Adjustment Factor QWQ (cfs) Outflow Volume (ft3) Storage Volume (ft3) 5 1.425 819 1.00 0.60 180 639 10 1.105 1270 1.00 0.60 360 910 15 0.935 1612 0.67 0.40 360 1252 20 0.805 1850 0.63 0.38 450 1400 25 0.715 2054 0.60 0.36 540 1514 30 0.650 2241 0.58 0.35 630 1611 35 0.585 2353 0.57 0.34 720 1633 40 0.535 2459 0.56 0.34 810 1649 45 0.495 2560 0.56 0.33 900 1660 50 0.460 2643 0.55 0.33 990 1653 55 0.435 2749 0.55 0.33 1080 1669 60 0.410 2827 0.54 0.33 1170 1657 65 0.385 2876 0.54 0.32 1260 1616 70 0.365 2936 0.54 0.32 1350 1586 75 0.345 2973 0.53 0.32 1440 1533 80 0.330 3034 0.53 0.32 1530 1504 85 0.315 3077 0.53 0.32 1620 1457 90 0.305 3154 0.53 0.32 1710 1444 95 0.290 3166 0.53 0.32 1800 1366 100 0.280 3218 0.53 0.32 1890 1328 105 0.270 3258 0.52 0.31 1980 1278 110 0.260 3286 0.52 0.31 2070 1216 115 0.255 3370 0.52 0.31 2160 1210 120 0.245 3378 0.52 0.31 2250 1128 *Note: Using the method described in FCSCM Chapter 6 Section 2.3 DETENTION POND CALCULATION; MODIFIED FAA METHOD w/ Ft Collins IDF Input Variables Results Required Detention Volume Fort Collins, Colorado 1853-001 Worthington Storage Project Number : Project Name : Isolator Row B1&OS2 A = Tc = Project Location : Design Point C = Design Storm Page 1 of 1 1853-001 Chamber Summary_B1_OS2.xlsx STORMTECH BASIN 4 Project Number:Pond No: Project Name:Calc. By: Project Location: Q=3.3LH1.5 Length (L)=5.00 ft 5,051.88 ft Weir Elev. =5,050.18 ft 5,046.66 ft Depth Above Crest - H (ft) Elevation (ft) Freeboard (ft) Flow (cfs) 0.00 5,050.18 1.70 0.00 0.10 5,050.28 1.60 0.52 0.20 5,050.38 1.50 1.48 0.30 5,050.48 1.40 2.71 0.40 5,050.58 1.30 4.17 0.50 5,050.68 1.20 5.83 0.60 5,050.78 1.10 7.67 0.70 5,050.88 1.00 9.66 0.80 5,050.98 0.90 11.81 0.90 5,051.08 0.80 14.09 1.00 5,051.18 0.70 16.50 1.25 5,051.43 0.45 23.06 1.50 5,051.68 0.20 30.31 1.70 5,051.88 0.00 36.57 Basin Invert Elev. = 100-Year Storm = 20.7 cfs LID Weir in Concrete Box F2 Input Parameters: Basin Rim Elev. = Depth vs. Flow: Governing Equations: This equation can be used to derive the stage-discharge relationship for a sharp crested weir where the depth of flow is small compared to the length of weir. Reference 1) Hydrologic Analysis and Design, Richard H McCuen, Prentice Hall, 1989. Pg.549. Fort Collins, Colorado * where Q is flow rate in CFS * where L is the crest length of the weir (FT) * where H is the height of flow over the crest (FT) Notes SHARP-CRESTED WEIR 1853-001 Stormtech Basin 4 Worthington Storage F. Wegert Rim of Basin 100-Year Storm NORTHERNENGINEERING.COM | 970.221.4158 FORT COLLINS | GREELEY STORMTECH BASIN 4 NORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: WORTHINGTON SELF STORAGE FORT COLLINS | GREELEY APPENDIX APPENDIX D EROSION CONTROL REPORT NORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: WORTHINGTON SELF STORAGE FORT COLLINS | GREELEY EROSION CONTROL REPORT EROSION CONTROL REPORT A comprehensive Erosion and Sediment Control Plan (along with associated details) has been included with the final construction drawings. It should be noted; however, any such Erosion and Sediment Control Plan serves only as a general guide to the Contractor. Staging and/or phasing of the BMPs depicted, and additional or different BMPs from those included may be necessary during construction, or as required by the authorities having jurisdiction. It shall be the responsibility of the Contractor to ensure erosion control measures are properly maintained and followed. The Erosion and Sediment Control Plan is intended to be a living document, constantly adapting to site conditions and needs. The Contractor shall update the location of BMPs as they are installed, removed, or modified in conjunction with construction activities. It is imperative to appropriately reflect the current site conditions at all times. The Erosion and Sediment Control Plan shall address both temporary measures to be implemented during construction, as well as permanent erosion control protection. Best Management Practices from the Volume 3, Chapter 7 – Construction BMPs will be utilized. Measures may include, but are not limited to, silt fencing and/or wattles along the disturbed perimeter, gutter protection in the adjacent roadways, and inlet protection at existing and proposed storm inlets. Vehicle tracking control pads, spill containment and clean-up procedures, designated concrete washout areas, dumpsters, and job site restrooms shall also be provided by the Contractor. Grading and Erosion Control Notes can be found on Sheet CS2 of the Utility Plans. The Final Utility Plans will also contain a full-size Erosion Control Plan as well as a separate sheet dedicated to Erosion Control Details. In addition to this report and the referenced plan sheets, the Contractor shall be aware of, and adhere to, the applicable requirements outlined in any existing Development Agreement(s) of record, as well as the Development Agreement, to be recorded prior to issuance of the Development Construction Permit. Also, the Site Contractor for this project may be required to secure a Stormwater Construction General Permit from the Colorado Department of Public Health and Environment (CDPHE), Water Quality Control Division – Stormwater Program, before commencing any earth disturbing activities. Prior to securing said permit, the Site Contractor shall develop a comprehensive Storm Water Management Plan (SWMP) pursuant to CDPHE requirements and guidelines. The SWMP will further describe and document the ongoing activities, inspections, and maintenance of construction BMPs. NNORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: TIMBER LARK RESIDENTIAL FORT COLLINS | GREELEY APPENDIX APPENDIX E USDA SOILS REPORT United States Department of Agriculture A product of the National Cooperative Soil Survey, a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local participants Custom Soil Resource Report for Larimer County Area, Colorado Worthington Storage Natural Resources Conservation Service February 17, 2022 Preface Soil surveys contain information that affects land use planning in survey areas. They highlight soil limitations that affect various land uses and provide information about the properties of the soils in the survey areas. Soil surveys are designed for many different users, including farmers, ranchers, foresters, agronomists, urban planners, community officials, engineers, developers, builders, and home buyers. Also, conservationists, teachers, students, and specialists in recreation, waste disposal, and pollution control can use the surveys to help them understand, protect, or enhance the environment. Various land use regulations of Federal, State, and local governments may impose special restrictions on land use or land treatment. Soil surveys identify soil properties that are used in making various land use or land treatment decisions. The information is intended to help the land users identify and reduce the effects of soil limitations on various land uses. The landowner or user is responsible for identifying and complying with existing laws and regulations. Although soil survey information can be used for general farm, local, and wider area planning, onsite investigation is needed to supplement this information in some cases. Examples include soil quality assessments (http://www.nrcs.usda.gov/wps/ portal/nrcs/main/soils/health/) and certain conservation and engineering applications. For more detailed information, contact your local USDA Service Center (https://offices.sc.egov.usda.gov/locator/app?agency=nrcs) or your NRCS State Soil Scientist (http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/contactus/? cid=nrcs142p2_053951). Great differences in soil properties can occur within short distances. Some soils are seasonally wet or subject to flooding. Some are too unstable to be used as a foundation for buildings or roads. Clayey or wet soils are poorly suited to use as septic tank absorption fields. A high water table makes a soil poorly suited to basements or underground installations. The National Cooperative Soil Survey is a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local agencies. The Natural Resources Conservation Service (NRCS) has leadership for the Federal part of the National Cooperative Soil Survey. Information about soils is updated periodically. Updated information is available through the NRCS Web Soil Survey, the site for official soil survey information. The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, reprisal, or because all or a part of an individual's income is derived from any public assistance program. (Not all prohibited bases apply to all programs.) Persons with disabilities who require 2 alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USDA's TARGET Center at (202) 720-2600 (voice and TDD). To file a complaint of discrimination, write to USDA, Director, Office of Civil Rights, 1400 Independence Avenue, S.W., Washington, D.C. 20250-9410 or call (800) 795-3272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportunity provider and employer. 3 Contents Preface....................................................................................................................2 How Soil Surveys Are Made..................................................................................5 Soil Map..................................................................................................................8 Soil Map................................................................................................................9 Legend................................................................................................................10 Map Unit Legend................................................................................................11 Map Unit Descriptions.........................................................................................11 Larimer County Area, Colorado......................................................................13 73—Nunn clay loam, 0 to 1 percent slopes.................................................13 74—Nunn clay loam, 1 to 3 percent slopes.................................................14 References............................................................................................................16 4 How Soil Surveys Are Made Soil surveys are made to provide information about the soils and miscellaneous areas in a specific area. They include a description of the soils and miscellaneous areas and their location on the landscape and tables that show soil properties and limitations affecting various uses. Soil scientists observed the steepness, length, and shape of the slopes; the general pattern of drainage; the kinds of crops and native plants; and the kinds of bedrock. They observed and described many soil profiles. A soil profile is the sequence of natural layers, or horizons, in a soil. The profile extends from the surface down into the unconsolidated material in which the soil formed or from the surface down to bedrock. The unconsolidated material is devoid of roots and other living organisms and has not been changed by other biological activity. Currently, soils are mapped according to the boundaries of major land resource areas (MLRAs). MLRAs are geographically associated land resource units that share common characteristics related to physiography, geology, climate, water resources, soils, biological resources, and land uses (USDA, 2006). Soil survey areas typically consist of parts of one or more MLRA. The soils and miscellaneous areas in a survey area occur in an orderly pattern that is related to the geology, landforms, relief, climate, and natural vegetation of the area. Each kind of soil and miscellaneous area is associated with a particular kind of landform or with a segment of the landform. By observing the soils and miscellaneous areas in the survey area and relating their position to specific segments of the landform, a soil scientist develops a concept, or model, of how they were formed. Thus, during mapping, this model enables the soil scientist to predict with a considerable degree of accuracy the kind of soil or miscellaneous area at a specific location on the landscape. Commonly, individual soils on the landscape merge into one another as their characteristics gradually change. To construct an accurate soil map, however, soil scientists must determine the boundaries between the soils. They can observe only a limited number of soil profiles. Nevertheless, these observations, supplemented by an understanding of the soil-vegetation-landscape relationship, are sufficient to verify predictions of the kinds of soil in an area and to determine the boundaries. Soil scientists recorded the characteristics of the soil profiles that they studied. They noted soil color, texture, size and shape of soil aggregates, kind and amount of rock fragments, distribution of plant roots, reaction, and other features that enable them to identify soils. After describing the soils in the survey area and determining their properties, the soil scientists assigned the soils to taxonomic classes (units). Taxonomic classes are concepts. Each taxonomic class has a set of soil characteristics with precisely defined limits. The classes are used as a basis for comparison to classify soils systematically. Soil taxonomy, the system of taxonomic classification used in the United States, is based mainly on the kind and character of soil properties and the arrangement of horizons within the profile. After the soil 5 scientists classified and named the soils in the survey area, they compared the individual soils with similar soils in the same taxonomic class in other areas so that they could confirm data and assemble additional data based on experience and research. The objective of soil mapping is not to delineate pure map unit components; the objective is to separate the landscape into landforms or landform segments that have similar use and management requirements. Each map unit is defined by a unique combination of soil components and/or miscellaneous areas in predictable proportions. Some components may be highly contrasting to the other components of the map unit. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The delineation of such landforms and landform segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, onsite investigation is needed to define and locate the soils and miscellaneous areas. Soil scientists make many field observations in the process of producing a soil map. The frequency of observation is dependent upon several factors, including scale of mapping, intensity of mapping, design of map units, complexity of the landscape, and experience of the soil scientist. Observations are made to test and refine the soil-landscape model and predictions and to verify the classification of the soils at specific locations. Once the soil-landscape model is refined, a significantly smaller number of measurements of individual soil properties are made and recorded. These measurements may include field measurements, such as those for color, depth to bedrock, and texture, and laboratory measurements, such as those for content of sand, silt, clay, salt, and other components. Properties of each soil typically vary from one point to another across the landscape. Observations for map unit components are aggregated to develop ranges of characteristics for the components. The aggregated values are presented. Direct measurements do not exist for every property presented for every map unit component. Values for some properties are estimated from combinations of other properties. While a soil survey is in progress, samples of some of the soils in the area generally are collected for laboratory analyses and for engineering tests. Soil scientists interpret the data from these analyses and tests as well as the field-observed characteristics and the soil properties to determine the expected behavior of the soils under different uses. Interpretations for all of the soils are field tested through observation of the soils in different uses and under different levels of management. Some interpretations are modified to fit local conditions, and some new interpretations are developed to meet local needs. Data are assembled from other sources, such as research information, production records, and field experience of specialists. For example, data on crop yields under defined levels of management are assembled from farm records and from field or plot experiments on the same kinds of soil. Predictions about soil behavior are based not only on soil properties but also on such variables as climate and biological activity. Soil conditions are predictable over long periods of time, but they are not predictable from year to year. For example, soil scientists can predict with a fairly high degree of accuracy that a given soil will have a high water table within certain depths in most years, but they cannot predict that a high water table will always be at a specific level in the soil on a specific date. After soil scientists located and identified the significant natural bodies of soil in the survey area, they drew the boundaries of these bodies on aerial photographs and Custom Soil Resource Report 6 identified each as a specific map unit. Aerial photographs show trees, buildings, fields, roads, and rivers, all of which help in locating boundaries accurately. Custom Soil Resource Report 7 Soil Map The soil map section includes the soil map for the defined area of interest, a list of soil map units on the map and extent of each map unit, and cartographic symbols displayed on the map. Also presented are various metadata about data used to produce the map, and a description of each soil map unit. 8 9 Custom Soil Resource Report Soil Map 4489180448920044892204489240448926044892804489300448932044893404489360448938044891804489200448922044892404489260448928044893004489320448934044893604489380491910 491930 491950 491970 491990 492010 492030 492050 491910 491930 491950 491970 491990 492010 492030 492050 40° 33' 18'' N 105° 5' 44'' W40° 33' 18'' N105° 5' 37'' W40° 33' 11'' N 105° 5' 44'' W40° 33' 11'' N 105° 5' 37'' WN Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 13N WGS84 0 50 100 200 300 Feet 0 15 30 60 90 Meters Map Scale: 1:1,070 if printed on A portrait (8.5" x 11") sheet. Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Map Unit Polygons Soil Map Unit Lines Soil Map Unit Points Special Point Features Blowout Borrow Pit Clay Spot Closed Depression Gravel Pit Gravelly Spot Landfill Lava Flow Marsh or swamp Mine or Quarry Miscellaneous Water Perennial Water Rock Outcrop Saline Spot Sandy Spot Severely Eroded Spot Sinkhole Slide or Slip Sodic Spot Spoil Area Stony Spot Very Stony Spot Wet Spot Other Special Line Features Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Larimer County Area, Colorado Survey Area Data: Version 16, Sep 2, 2021 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Aug 11, 2018—Aug 12, 2018 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Custom Soil Resource Report 10 Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI 73 Nunn clay loam, 0 to 1 percent slopes 0.0 1.1% 74 Nunn clay loam, 1 to 3 percent slopes 3.1 98.9% Totals for Area of Interest 3.1 100.0% Map Unit Descriptions The map units delineated on the detailed soil maps in a soil survey represent the soils or miscellaneous areas in the survey area. The map unit descriptions, along with the maps, can be used to determine the composition and properties of a unit. A map unit delineation on a soil map represents an area dominated by one or more major kinds of soil or miscellaneous areas. A map unit is identified and named according to the taxonomic classification of the dominant soils. Within a taxonomic class there are precisely defined limits for the properties of the soils. On the landscape, however, the soils are natural phenomena, and they have the characteristic variability of all natural phenomena. Thus, the range of some observed properties may extend beyond the limits defined for a taxonomic class. Areas of soils of a single taxonomic class rarely, if ever, can be mapped without including areas of other taxonomic classes. Consequently, every map unit is made up of the soils or miscellaneous areas for which it is named and some minor components that belong to taxonomic classes other than those of the major soils. Most minor soils have properties similar to those of the dominant soil or soils in the map unit, and thus they do not affect use and management. These are called noncontrasting, or similar, components. They may or may not be mentioned in a particular map unit description. Other minor components, however, have properties and behavioral characteristics divergent enough to affect use or to require different management. These are called contrasting, or dissimilar, components. They generally are in small areas and could not be mapped separately because of the scale used. Some small areas of strongly contrasting soils or miscellaneous areas are identified by a special symbol on the maps. If included in the database for a given area, the contrasting minor components are identified in the map unit descriptions along with some characteristics of each. A few areas of minor components may not have been observed, and consequently they are not mentioned in the descriptions, especially where the pattern was so complex that it was impractical to make enough observations to identify all the soils and miscellaneous areas on the landscape. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The objective of mapping is not to delineate pure taxonomic classes but rather to separate the landscape into landforms or landform segments that have similar use and management requirements. The delineation of such segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, however, Custom Soil Resource Report 11 onsite investigation is needed to define and locate the soils and miscellaneous areas. An identifying symbol precedes the map unit name in the map unit descriptions. Each description includes general facts about the unit and gives important soil properties and qualities. Soils that have profiles that are almost alike make up a soil series. Except for differences in texture of the surface layer, all the soils of a series have major horizons that are similar in composition, thickness, and arrangement. Soils of one series can differ in texture of the surface layer, slope, stoniness, salinity, degree of erosion, and other characteristics that affect their use. On the basis of such differences, a soil series is divided into soil phases. Most of the areas shown on the detailed soil maps are phases of soil series. The name of a soil phase commonly indicates a feature that affects use or management. For example, Alpha silt loam, 0 to 2 percent slopes, is a phase of the Alpha series. Some map units are made up of two or more major soils or miscellaneous areas. These map units are complexes, associations, or undifferentiated groups. A complex consists of two or more soils or miscellaneous areas in such an intricate pattern or in such small areas that they cannot be shown separately on the maps. The pattern and proportion of the soils or miscellaneous areas are somewhat similar in all areas. Alpha-Beta complex, 0 to 6 percent slopes, is an example. An association is made up of two or more geographically associated soils or miscellaneous areas that are shown as one unit on the maps. Because of present or anticipated uses of the map units in the survey area, it was not considered practical or necessary to map the soils or miscellaneous areas separately. The pattern and relative proportion of the soils or miscellaneous areas are somewhat similar. Alpha-Beta association, 0 to 2 percent slopes, is an example. An undifferentiated group is made up of two or more soils or miscellaneous areas that could be mapped individually but are mapped as one unit because similar interpretations can be made for use and management. The pattern and proportion of the soils or miscellaneous areas in a mapped area are not uniform. An area can be made up of only one of the major soils or miscellaneous areas, or it can be made up of all of them. Alpha and Beta soils, 0 to 2 percent slopes, is an example. Some surveys include miscellaneous areas. Such areas have little or no soil material and support little or no vegetation. Rock outcrop is an example. Custom Soil Resource Report 12 Larimer County Area, Colorado 73—Nunn clay loam, 0 to 1 percent slopes Map Unit Setting National map unit symbol: 2tlng Elevation: 4,100 to 5,700 feet Mean annual precipitation: 14 to 15 inches Mean annual air temperature: 48 to 52 degrees F Frost-free period: 135 to 152 days Farmland classification: Prime farmland if irrigated Map Unit Composition Nunn and similar soils:85 percent Minor components:15 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Nunn Setting Landform:Terraces Landform position (three-dimensional):Tread Down-slope shape:Linear Across-slope shape:Linear Parent material:Pleistocene aged alluvium and/or eolian deposits Typical profile Ap - 0 to 6 inches: clay loam Bt1 - 6 to 10 inches: clay loam Bt2 - 10 to 26 inches: clay loam Btk - 26 to 31 inches: clay loam Bk1 - 31 to 47 inches: loam Bk2 - 47 to 80 inches: loam Properties and qualities Slope:0 to 1 percent Depth to restrictive feature:More than 80 inches Drainage class:Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat):Moderately low to moderately high (0.06 to 0.20 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Calcium carbonate, maximum content:7 percent Maximum salinity:Nonsaline (0.1 to 1.0 mmhos/cm) Sodium adsorption ratio, maximum:0.5 Available water supply, 0 to 60 inches: High (about 9.1 inches) Interpretive groups Land capability classification (irrigated): 3e Land capability classification (nonirrigated): 4e Hydrologic Soil Group: C Ecological site: R067BY042CO - Clayey Plains Hydric soil rating: No Custom Soil Resource Report 13 Minor Components Heldt Percent of map unit:10 percent Landform:Terraces Landform position (three-dimensional):Tread Down-slope shape:Linear Across-slope shape:Linear Ecological site:R067BY042CO - Clayey Plains Hydric soil rating: No Wages Percent of map unit:5 percent Landform:Terraces Landform position (three-dimensional):Tread Down-slope shape:Linear Across-slope shape:Linear Ecological site:R067BY002CO - Loamy Plains Hydric soil rating: No 74—Nunn clay loam, 1 to 3 percent slopes Map Unit Setting National map unit symbol: 2tlpl Elevation: 3,900 to 5,840 feet Mean annual precipitation: 13 to 17 inches Mean annual air temperature: 50 to 54 degrees F Frost-free period: 135 to 160 days Farmland classification: Prime farmland if irrigated Map Unit Composition Nunn and similar soils:85 percent Minor components:15 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Nunn Setting Landform:Terraces Landform position (three-dimensional):Tread Down-slope shape:Linear Across-slope shape:Linear Parent material:Pleistocene aged alluvium and/or eolian deposits Typical profile Ap - 0 to 9 inches: clay loam Bt - 9 to 13 inches: clay loam Btk - 13 to 25 inches: clay loam Bk1 - 25 to 38 inches: clay loam Bk2 - 38 to 80 inches: clay loam Custom Soil Resource Report 14 Properties and qualities Slope:1 to 3 percent Depth to restrictive feature:More than 80 inches Drainage class:Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat):Moderately low to moderately high (0.06 to 0.20 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Calcium carbonate, maximum content:7 percent Maximum salinity:Nonsaline to very slightly saline (0.1 to 2.0 mmhos/cm) Sodium adsorption ratio, maximum:0.5 Available water supply, 0 to 60 inches: High (about 9.9 inches) Interpretive groups Land capability classification (irrigated): 2e Land capability classification (nonirrigated): 3e Hydrologic Soil Group: C Ecological site: R067BY042CO - Clayey Plains Hydric soil rating: No Minor Components Heldt Percent of map unit:10 percent Landform:Terraces Landform position (three-dimensional):Tread Down-slope shape:Linear Across-slope shape:Linear Ecological site:R067BY042CO - Clayey Plains Hydric soil rating: No Satanta Percent of map unit:5 percent Landform:Terraces Landform position (three-dimensional):Tread Down-slope shape:Linear Across-slope shape:Linear Ecological site:R067BY002CO - Loamy Plains Hydric soil rating: No Custom Soil Resource Report 15 References American Association of State Highway and Transportation Officials (AASHTO). 2004. Standard specifications for transportation materials and methods of sampling and testing. 24th edition. American Society for Testing and Materials (ASTM). 2005. Standard classification of soils for engineering purposes. ASTM Standard D2487-00. Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of wetlands and deep-water habitats of the United States. U.S. Fish and Wildlife Service FWS/OBS-79/31. Federal Register. July 13, 1994. Changes in hydric soils of the United States. Federal Register. September 18, 2002. Hydric soils of the United States. Hurt, G.W., and L.M. Vasilas, editors. Version 6.0, 2006. Field indicators of hydric soils in the United States. National Research Council. 1995. Wetlands: Characteristics and boundaries. Soil Survey Division Staff. 1993. Soil survey manual. Soil Conservation Service. U.S. Department of Agriculture Handbook 18. http://www.nrcs.usda.gov/wps/portal/ nrcs/detail/national/soils/?cid=nrcs142p2_054262 Soil Survey Staff. 1999. Soil taxonomy: A basic system of soil classification for making and interpreting soil surveys. 2nd edition. Natural Resources Conservation Service, U.S. Department of Agriculture Handbook 436. http:// www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053577 Soil Survey Staff. 2010. Keys to soil taxonomy. 11th edition. U.S. Department of Agriculture, Natural Resources Conservation Service. http:// www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053580 Tiner, R.W., Jr. 1985. Wetlands of Delaware. U.S. Fish and Wildlife Service and Delaware Department of Natural Resources and Environmental Control, Wetlands Section. United States Army Corps of Engineers, Environmental Laboratory. 1987. Corps of Engineers wetlands delineation manual. Waterways Experiment Station Technical Report Y-87-1. United States Department of Agriculture, Natural Resources Conservation Service. National forestry manual. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/ home/?cid=nrcs142p2_053374 United States Department of Agriculture, Natural Resources Conservation Service. National range and pasture handbook. http://www.nrcs.usda.gov/wps/portal/nrcs/ detail/national/landuse/rangepasture/?cid=stelprdb1043084 16 United States Department of Agriculture, Natural Resources Conservation Service. National soil survey handbook, title 430-VI. http://www.nrcs.usda.gov/wps/portal/ nrcs/detail/soils/scientists/?cid=nrcs142p2_054242 United States Department of Agriculture, Natural Resources Conservation Service. 2006. Land resource regions and major land resource areas of the United States, the Caribbean, and the Pacific Basin. U.S. Department of Agriculture Handbook 296. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/? cid=nrcs142p2_053624 United States Department of Agriculture, Soil Conservation Service. 1961. Land capability classification. U.S. Department of Agriculture Handbook 210. http:// www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_052290.pdf Custom Soil Resource Report 17 NORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: TIMBER LARK RESIDENTIAL FORT COLLINS | GREELEY APPENDIX APPENDIX F EXCERPTS FROM CENTRE FOR ADVANCED TECHNOLOGY 16TH FILING NORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: TIMBER LARK RESIDENTIAL FORT COLLINS | GREELEY APPENDIX MAP POCKET DR1 – DRAINAGE EXHIBIT STSTSTSTSTSTSTSTSTSTC VAULT ELEC ELEC C ELEC E D FE SD D D T CONTROL IRR GXXX TTTTTTVAULT F.O. OS2 OWNER: TALL DENTIST LLC 1001 CENTRE AVE DODSANITY LLC 1013 CENTRE AVE (EMPLOYMENT DISTRICT) OWNER: KATSCH24 LLC 1007 CENTRE AVE OWNER: AWEIDA PROPERTIES INC 2500 S SHIELDS ST OWNER: AWEIDA PROPERTIES INC 2514 S SHIELDS ST OWNER: WARPAL LLC 1044 W DRAKE RD MARKET CENTRE RETAIL ASSOCIATION OWNER: TWO PAULS LLC 932 W DRAKE RD OWNER: ROBERT WILSON 2526 WORTHINGTON CIRCLE OWNER: COLUMBINE MEDICAL REAL ESTATE LLC 915 CENTRE AVE CENTRE AVENUE WO R T H I NG TO N C I R C L E S SHIELDS STREETP R I V A T E A C C E S S R O A DPRIVATE ACCESS ROADEXISTING DETENTION POND 1 PRIVA T E A C C E S S R O A D EXISTING BUILDING 2.27 ac. H1 4.81 ac. H2 0.43 ac. H3 OS1 OS3 EXISTING 15" RCP STORM DRAIN EXISTING STORM MANHOLE AND RESTRICTOR PLATE SheetThese drawings areinstruments of serviceprovided by NorthernEngineering Services, Inc.and are not to be used forany type of constructionunless signed and sealed bya Professional Engineer inthe employ of NorthernEngineering Services, Inc.NOT FOR CONSTRUCTIONREVIEW SETENGINEERNGIEHTRONRNFORT COLLINS: 301 North Howes Street, Suite 100, 80521GREELEY: 820 8th Street, 80631970.221.4158northernengineering.comof 27WORTHINGTON SELF STORAGEDR1 HISTORIC DRAINAGE EXHIBIT26 PROPOSED CONTOUR PROPOSED STORM SEWER PROPOSED SWALE EXISTING CONTOUR PROPOSED CURB & GUTTER PROPERTY BOUNDARY PROPOSED INLET A DESIGN POINT FLOW ARROW DRAINAGE BASIN LABEL DRAINAGE BASIN BOUNDARY PROPOSED SWALE SECTION 11 NOTES: 1.REFER TO THE FINAL DRAINAGE REPORT, DATED DECEMBER 21, 2022 FOR ADDITIONAL INFORMATION. A LEGEND: FOR DRAINAGE REVIEW ONLY NOT FOR CONSTRUCTION PROPOSED 100-YR WSEL NORTH ( IN FEET ) 0 1 INCH = 40 FEET 40 40 80 120 STSTSTS S S S C S S S C D D D T CONTROL IRR GXXX TTTTTTVAULT F.O.XXXXXXXXWUDUDUDUDUD UDUDUDUD UDUDUDUDUDUD UDIRUDUDUD1.93 ac. OS1 1.57 ac. OS2 0.31 ac. A2 1.47 ac. B1 1.14 ac. B2 0.32 ac. OS3 a2 os3 os1 os2 b2 b1 PROPOSED MANHOLE CONNECTION TO EXISTING 15" STORM PROPOSED CURB INLET PROPOSED AREA INLET PROPOSED CURB INLET SITE OUTFALL PIPE 15" RCP a10.23 ac. A1 PROPOSED AREA INLET OWNER: TALL DENTIST LLC 1001 CENTRE AVE DODSANITY LLC 1013 CENTRE AVE (EMPLOYMENT DISTRICT) OWNER: KATSCH24 LLC 1007 CENTRE AVE OWNER: AWEIDA PROPERTIES INC 2500 S SHIELDS ST OWNER: AWEIDA PROPERTIES INC 2514 S SHIELDS ST OWNER: WARPAL LLC 1044 W DRAKE RD MARKET CENTRE RETAIL ASSOCIATION OWNER: TWO PAULS LLC 932 W DRAKE RD OWNER: ROBERT WILSON 2526 WORTHINGTON CIRCLE OWNER: COLUMBINE MEDICAL REAL ESTATE LLC 915 CENTRE AVE CENTRE AVENUE WO R T H I NG TO N C I R C L E S SHIELDS STREETP R I V A T E A C C E S S R O A DPRIVATE ACCESS ROADDETENTION AREA 1 (R-TANK BASIN 1 & STORMTECH BASIN 1 & 2) PRIVA T E A C C E S S R O A D EXISTING BUILDING PROPOSED BUILDING PROPOSED GARAGE PROPOSED GARAGE PROPOSED GARAGE R-TANK BASIN 3R-TANK BASIN 1 STORMTECH BASIN 1 STORMTE C H BASIN 2 R-TANK BASIN 2 DETENTION AREA 2 (R-TANK BASIN 2,3 & STORMTECH BASIN 2, 3, 4 & 5) STORMTECH BASIN 3 STORMTECH BASIN 4 STORMTECH BASIN 5 EXISTING EMERGENCY SPILLWAY CROWN OF WORTHINGTON CIRCLE SheetThese drawings areinstruments of serviceprovided by NorthernEngineering Services, Inc.and are not to be used forany type of constructionunless signed and sealed bya Professional Engineer inthe employ of NorthernEngineering Services, Inc.NOT FOR CONSTRUCTIONREVIEW SETENGINEERNGIEHTRONRNFORT COLLINS: 301 North Howes Street, Suite 100, 80521GREELEY: 820 8th Street, 80631970.221.4158northernengineering.comof 32WORTHINGTON STORAGEDR1 DRAINAGE EXHIBIT32 PROPOSED CONTOUR PROPOSED STORM SEWER PROPOSED SWALE EXISTING CONTOUR PROPOSED CURB & GUTTER PROPERTY BOUNDARY PROPOSED INLET A DESIGN POINT FLOW ARROW DRAINAGE BASIN LABEL DRAINAGE BASIN BOUNDARY PROPOSED SWALE SECTION 11 NOTES: 1.REFER TO THE FINAL DRAINAGE REPORT, DATED APRIL 26, 2023 FOR ADDITIONAL INFORMATION. A LEGEND: FOR DRAINAGE REVIEW ONLY NOT FOR CONSTRUCTION PROPOSED 100-YR WSEL NORTH ( IN FEET ) 0 1 INCH = 40 FEET 40 40 80 120 DEVELOPED DRAINAGE SUMMARY Design Point Basin ID Total Area (acres) C2 C100 2-Yr Tc (min) 100-Yr Tc (min) Q2 (cfs) Q100 (cfs) a1 A1 0.234 0.26 0.33 6.02 6.02 0.16 0.74 a2 A2 0.315 0.74 0.92 5.00 5.00 0.66 2.88 b1 B1 1.467 0.85 1.00 5.00 5.00 3.57 14.59 b2 B2 1.143 0.87 1.00 5.00 5.00 2.84 11.37 OFFSITE BASINS os1 OS1 1.929 0.71 0.89 7.69 7.69 3.39 17.15 os2 OS2 1.570 0.43 0.53 11.89 11.89 1.40 6.09 os3 OS3 0.324 0.81 1.00 5.00 5.00 0.74 3.22 CALL 2 BUSINESS DAYS IN ADVANCE BEFORE YOU DIG, GRADE, OR EXCAVATE FOR THE MARKING OF UNDERGROUND MEMBER UTILITIES. CALL UTILITY NOTIFICATION CENTER OF COLORADO Know what'sbelow. before you dig.Call R Historic Release Rate Description Q100 Notes Historic Site 1.91 cfs Release rate per Centre for Advanced Technology 10th & 16th. Developed Release Rate Description Q100 Notes Detention Area 1 0.25 cfs Release rate for Detention Area 1 (R-Tank Basin 1) Detention Area 2 1.66 cfs Release rate for Detention Area 2 (R-Tank Basin 2, 3 & Stormtech Basin 5) Total release rate 1.91 cfs Total release rate for Detention Areas 1 and 2. Required release rate 1.91 cfs Release rate per Centre for Advanced Technology 10th & 16th. Summary of Detention Volumes per R-Tank Basin Underground Vault Volume Notes R-Tank Basin 1 30,138 cu. ft.Release rate for Detention Area 1. R-Tank Basin 2 19,024 cu. ft.Release rate for Detention Area 2. R-Tank Basin 3 11,195 cu. ft.Release rate for Detention Area 2. Stormtech Basin 5 6,703 cu. ft.Release rate for Detention Area 2. Total of Detention Area 1 30,138 cu. ft.Total design volume of R-Tanks in Detention Area 1. Req. Vol. of Detention Area 1 30,101 cu. ft.Required detention volume of Detention Area 1. Total of Detention Area 2 36,922 cu. ft.Total design volume of R-Tanks in Detention Area 2. Req. Vol. of Detention Area 2 36,226 cu. ft.Required detention volume of Detention Area 2. Summary of Water Quality Volumes per Stormtech Basin Underground Vault Volume Chambers Required Notes Stormtech Basin 1 525 cu. ft.3 - MC 3500 Design water quality volume for Basins A1 & OS3. Req. Vol. Stormtech Basin 1 408 cu. ft.Required water quality volume for Basins A1 & OS3. Stormtech Basin 2 2,450 cu. ft.14 - MC 3500 Design water quality volume for Basins A2 & OS1. Req. Vol. Stormtech Basin 2 2,079 cu. ft.Required water quality volume for Basins A2 & OS1. Stormtech Basin 3 1,575 cu. ft.16 - MC 3500 Design water quality volume for Basins B2. Req. Vol. Stormtech Basin 3 1,410 cu. ft.Required water quality volume for Basins B2. Stormtech Basin 4 2,800 cu. ft.9 - MC 3500 Design water quality volume for Basin B1 & OS2. Req. Vol. Stormtech Basin 4 2,367 cu. ft.Required water quality volume for Basin B1 & OS2.