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Home My WebLink AboutI-25 & MULBERRY - OVERALL DEVELOPMENT PLAN - ODP220002 - SUBMITTAL DOCUMENTS - ROUND 1 - DRAINAGE REPORTODP DRAINAGE REPORT FOR I-25 & Mulberry Commercial Development Fort Collins Prepared For: Miller Mokler, LLC 6900 E. Belleview Ave, Suite 300 Greenwood Village, CO 80111 Steve Shoflick (303) 929-7002 September 2022 Project No. 39789.00 Prepared By: JR Engineering, LLC 2900 South College Avenue, Suite 3D Fort Collins, CO 80525 I-25 & Mulberry Commercial Development Fort Collins ODP Drainage Report ii TABLE OF CONTENTS TABLE OF CONTENTS ......................................................................................................................... ii APPENDIX ...................................................................................................................................... ii Engineer’s Certification Block ........................................................................................................... iii GENERAL LOCATION & EXISTING SITE DESCRIPTION .......................................................................... 1 LOCATION ..................................................................................................................................... 1 DESCRIPTION OF PROPERTY .......................................................................................................... 1 MASTER DRAINAGE BASIN DESCRIPTION ........................................................................................... 2 COOPER SLOUGH/BOXELDER DRAINAGE BASIN ............................................................................. 2 FLOODPLAIN INFORMATION ............................................................................................................. 2 FLOODPLAIN SUBMITTAL REQUIREMENTS ..................................................................................... 2 PROJECT DESCRIPTION ...................................................................................................................... 3 PROJECT SUMMARY ...................................................................................................................... 3 PROPOSED DRAINAGE FACILITIES .................................................................................................. 3 DRAINAGE BASINS AND SUB-BASINS ................................................................................................. 4 MAJOR BASINS AND SUB-BASINS ................................................................................................... 4 EXISTING SUB-BASIN DESCRIPTION ................................................................................................ 5 EXISTING OFFSITE DRAINAGE BASINS ............................................................................................ 5 DRAINAGE DESIGN CRITERIA ............................................................................................................. 6 REGULATIONS ............................................................................................................................... 6 MINIMIZATION OF THE DCIA ......................................................................................................... 6 DEVELOPMENT CRITERIA REFERENCE AND CONSTRAINTS ............................................................. 6 HYDROLOGIC CRITERIA .................................................................................................................. 6 HYDRAULIC CRITERIA ..................................................................................................................... 7 FLOODPLAIN REGULATIONS COMPLIANCE ..................................................................................... 7 CONCLUSIONS ................................................................................................................................... 7 COMPLIANCE WITH STANDARDS ................................................................................................... 7 REFERENCES ...................................................................................................................................... 8 APPENDIX Appendix A – Figures Appendix B – SWMM Results Appendix C – Hydraulic Calculations Appendix D – Maps I-25 & Mulberry Commercial Development Fort Collins ODP Drainage Report iii Engineer’s Certification Block I hereby attest that this report for the ODP drainage design for the I-25 & Mulberry Commercial Development Fort Collins was prepared by me or under my direct supervision, in accordance with the provisions of the Fort Collins Stormwater Criteria Manual. I understand that the City of Fort Collins does not and will not assume liability for drainage facilities designed by others. Timothy J. Halopoff, PE, CFM Registered Professional Engineer State of Colorado No. 37953 I-25 & Mulberry Commercial Development Fort Collins ODP Drainage Report 1 GENERAL LOCATION & EXISTING SITE DESCRIPTION LOCATION The site is located in the North East Quarter of the South West Quarter of Section 10, Township 7 North, Range 68 West of the 6th Principal Meridian in the City of Fort Collins, Larimer County, Colorado. The site is located adjacent to Interstate 25 and East Mulberry Street. More specifically, the site is a 46.92 acre property that is currently undeveloped, and was previously used as farmland. Sunstate Equipment, LLC lies directly southeast of the site. Directly to the east of this site across Cloverleaf Way is the Cloverleaf Community. Across Mulberry Street to the south lies Air Care Colorado as well as a number of other commercial developments. The subject property is located within the Boxelder Cooper Slough Master Drainage Basin. DESCRIPTION OF PROPERTY The I-25 & Mulberry Commercial Development site is 46.92 acres at the northeast corner of I-25 & Mulberry. The existing site is currently undeveloped, low lying flat land. The existing site generally slopes from north to southwest with slopes ranging between 0.60% and 1%. Due to the minimal slopes that exist on and around the site, minimal slopes are required in swales and storm pipe in the proposed condition. The property is generally covered with sparse native grasses. There is a ditch along the east property boundary that drains from the northeast corner to the southeast corner to an existing 24” CMP south of the site, that outfalls to a large swale along the south side of Mulberry Street to Boxelder Creek, which is located approximately 700 feet east of the site. The ditch receives the majority of the runoff from the Cloverleaf Development east of the property. The site is tributary to the Boxelder Creek Master Drainage Basin. There is a drainage swale starting from the northwest corner of the site traversing down to the most southern site corner adjacent to the Sunstate property. The swale receives runoff generated from roadways and properties to the north of the site that are detained inadvertently at the railroad crossing the frontage road, north of the site. Offsite flows currently collect in a depressed area on the land southwest of the site that has an on-site area inlet. The inlet captures some of the runoff and slowly conveys it south across Mulberry, through the Aircare Center out to Boxelder Creek. There is direct runoff received via sheet flow from the Industrial site directly north of the property. See Exhibit A in Appendix A. I-25 & Mulberry Commercial Development Fort Collins ODP Drainage Report 2 MASTER DRAINAGE BASIN DESCRIPTION COOPER SLOUGH/BOXELDER DRAINAGE BASIN The subject property is located within the Boxelder Cooper Slough Master Drainage Basin. The Boxelder Creek and Cooper Slough Basins encompass approximately 265 square miles; beginning north of the Colorado/Wyoming border and extending southward into east Fort Collins, where they end at the Cache la Poudre River. The basins are primarily characterized by farmland with isolated areas of mixed-use estate residential development and limited commercial development. It is anticipated the lower part of the basin will undergo urbanization in the future. The I-25 & Mulberry Commercial Development site is generally located east and central in the master drainage basin. Previously, the City of Fort Collins and Larimer County performed stream restoration and habitat improvements within Boxelder Creek that were completed by the Boxelder Stormwater Authority north of the I-25 & Mulberry Commercial Development’s primary outfall but not directly adjacent to the site. There are no further storm detention improvements necessary adjacent to the site. FLOODPLAIN INFORMATION FLOODPLAIN SUBMITTAL REQUIREMENTS The site is on FEMA FIRM panel 08069C1003G & 08069C0984H. The site currently lies within FEMA Zone X; areas which are determined to be outside the 0.2% annual chance floodplain. The site was previously located in site AE. The site is not located within a FEMA regulated floodplain. The Boxelder Stormwater Authority has completed improvements upstream of this site and the resulting floodplain mapping was approved by FEMA as of Feb 21st 2019. The I-25 & Mulberry site has been removed from the Boxelder Creek floodplain. The revised floodplain boundary map from FCMaps can be found in Appendix A. I-25 & Mulberry Commercial Development Fort Collins ODP Drainage Report 3 PROJECT DESCRIPTION PROJECT SUMMARY The I-25 & Mulberry Commercial Development is composed of approximately 46.92 acres of land currently zoned IL-light industrial. The property has been submitted to the City of Fort Collins for request for Annexation and Zoning. The request has been made in order to change the current IL zoning to both CS- Service Commercial and CG-General Commercial zoning. The entirety of the site will be used for various commercial and industrial uses. Southeast of the site is the Sunstate Equipment property. To the north is both the RMT Overland and Cactus Wellhead businesses. West of the site is I-25 and east of the site is the Cloverleaf Community. PROPOSED DRAINAGE FACILITIES The I-25 & Mulberry Commercial Development will need to construct drainage facilities to manage on site drainage, as well as manage the storm drainage from various areas of offsite flows. The Site will be divided into 3 main drainage basins. (See proposed drainage Map in Appendix D) Basin A is composed of approximately 7.84 acres located in the northwestern portion of the site. This area will be composed of roadway, parking lot area and commercial/industrial buildings. Runoff generated within this area will be conveyed via curb & gutter, sheet flow and storm pipes to a proposed detention facility called Pond A designed in order to reduce a portion of the runoff before ultimately discharging the flow into Pond B. Pond A is currently sized using SWMM to hold 1.7 acre-ft and not overflow during a 100-year rainfall event.. Basin B is composed of approximately 31.65 Acres located in the southeastern portion of the site. This area will be composed of roadway, parking lot area and commercial/industrial buildings. Runoff generated within this area will be conveyed via curb & gutter, sheet flow and storm pipes to a proposed detention facility called Pond B. Pond B will be a water quality/detention facility designed to treat site runoff. This pond has also been designed large enough to receive the offsite runoff generated from the property to the north of the site as well as the Cloverleaf Community to the East. A trapezoidal channel with a 2’ concrete pan at its base was designed to convey the offsite flows through the pond. The channel runs at 0.5% from the pond outfall structure north along the eastern edge of the property to the northern property line than east to the existing concrete pan discharging into the site from the north. A 48” RCP pipe has been designed as the pond outfall to Boxelder Creek to the east. The pipe has been designed to I-25 & Mulberry Commercial Development Fort Collins ODP Drainage Report 4 discharge 88 cfs with 5.5’ of head within the detention pond. The Boxelder Ditch Company has been contacted, and determined that Boxelder Creek Could receive up to the existing condition runoff untreated into the ditch which is approximately 92cfs. Pond B is currently sized to hold 12.0 acre-ft. Basin C is composes approximately 7.75 acres and is located in the western portion of the site. This area will be composed of parking lot area and commercial/retail buildings. Runoff generated within this area will be conveyed via sheet flow and trapezoidal channel to a proposed detention facility called Pond C. Pond C has been designed as a water quality/detention facility. Pond C will discharge into a proposed pipe along the decommissioned frontage road to an existing 24” storm pipe that crosses Mulberry, conveying flows to a large drainage ditch along the south side of Mulberry. The existing ditch along Mulberry runs east to Boxelder Creek. The existing 24” pipe will have 2-3 additional 24” RCPs or equivalent added across Mulberry in order to reduce flooding that occurs in the existing condition at Mulberry/Frontage intersection as well as act as an appropriate outfall for pond C. Pond C is currently sized to hold 1.2 acre- ft. LID systems such as sand filters, vegetative buffers, bioretention/bioswales, and raingardens will be incorporated into the overall commercial/industrial areas during project development plans in order to hit the 50% required LID treatment of impervious areas. DRAINAGE BASINS AND SUB-BASINS MAJOR BASINS AND SUB-BASINS The proposed I-25 & Mulberry Commercial Development site is located in the Boxelder Creek/ Cooper Slough basin. The Boxelder Creek/ Cooper Slough drainage basin extends along the east end of Fort Collins; from the basin beginning north of the Colorado/ Wyoming border extending southward into east Fort Collins, ending at the Cache la Poudre. It encompasses 265 square miles in the City of Fort Collins and Larimer County. Historically, the basin consisted of agricultural land with isolated areas of mixed-use residential development and limited commercial development. It is anticipated the lower part of the basin will experience significant urbanization. Most of the projects are located at the northwest and southwest I-25 & Mulberry Commercial Development Fort Collins ODP Drainage Report 5 corners of State Highway 14 and I-25, where the majority of the existing damage to structures is anticipated, which includes this I-25 & Mulberry Commercial Development. EXISTING SUB-BASIN DESCRIPTION There are offsite areas that flow across the proposed development site. The existing drainage basins within the site flow to the southwest of the site. The existing sub-basins can be found on the Offsite SWMM Map located in Appendix D. EXISTING OFFSITE DRAINAGE BASINS Currently the site collects offsite runoff from 3 locations: the northwest corner via a side road ditch (Q100 = 12.7 cfs), sheet flow from the north parking (Q100 = 54.8 cfs) and the east side of the property from various pans coming from the Cloverleaf Area (Q100 = 251.0cfs). Existing runoff from the northwest will be captured in a culvert and piped under the proposed configuration of the Frontage Road back to the existing channel located just off of the western property boundary. This flow is conveyed to the existing channel, south of Pond C where it will be captured in a Type C inlet and routed to the proposed quad 24” RCP or equivalent under Mulberry. The Runoff from the property north of the site will be contained within a 2’-4’ deep trapezoidal channel that runs from the middle of the north end of the site to the eastern property line, then south into proposed detention Pond B. Offsite flows coming into the site via existing concrete pans and sheet flow from the Cloverleaf Development to the east will be captured in the same trapezoidal channel along the eastern property line into Pond B. All offsite runoff is ultimately conveyed to Boxelder Creek. Offsite flows were evaluated utilizing EPA SWMM Version 5.1. A map summarizing the SWMM model and flows can be found in Appendix D. The results from the SWMM modeling as well as all flows entering the site for the 100-year storm event can be found within Appendix B. Other offsite flows and upstream basins were evaluated utilizing SWMM in order to accurately represent the off-site flows that enter the site. The SWMM results as well as an offsite basin map can be found in Appendix D. I-25 & Mulberry Commercial Development Fort Collins ODP Drainage Report 6 DRAINAGE DESIGN CRITERIA REGULATIONS This report was prepared to meet or exceed the City of Fort Collins stormwater criteria. The City of Fort Collins Stormwater Criteria Manual (dated 2018)(FCSCM) and the Urban Drainage Flood Control District’s (UDFCD) Drainage Criteria Manual (USDCM) Volumes 1, 2 and 3 were referenced as guidelines for this design. MINIMIZATION OF THE DCIA UDFCD recommends the Four Step Process to protect receiving waters. The four step process incorporates reducing runoff volume, treating water quality capture volume, stabilizing streams, and implementing long-term source controls. Volume reduction is an important part of the Four Step Process and is fundamental to effective stormwater management. Per City criteria, a minimum of 75 percent of new impervious surface area must be treated by a Low-Impact Development (LID) best management practice (BMP). The proposed LID BMPs will have the effect of slowing runoff through the site lot and increasing infiltration and rainfall interception by encouraging infiltration and careful selection of vegetative cover. The improvements will decrease the runoff coefficient from the site and are expected to have no adverse impact on the timing, quantity, or quality of stormwater runoff. DEVELOPMENT CRITERIA REFERENCE AND CONSTRAINTS The master drainage report for the Boxelder Creek Drainage Basin was prepared by ICON Engineering, Inc. April 9th, 2002. I-25 & Mulberry Commercial Development falls within element 30 in the SWMM file associated with the master drainage report. The development of the I-25 & Mulberry site must not have a negative impact on downstream discharges, volumes and water surface elevations. The elements directly downstream from the I-25 & Mulberry Commercial Development site are elements 47 and 29 from the master SWMM file. HYDROLOGIC CRITERIA SWMM was utilized in conjunction with The City of Fort Collins Stormwater Criteria Manual to determine basin runoff characteristics and rainfall intensities. I-25 & Mulberry Commercial Development Fort Collins ODP Drainage Report 7 HYDRAULIC CRITERIA The ultimate I-25 & Mulberry Commercial Development storm drainage system will be designed to convey the minor and major storm events through the property with the proposed inlets, storm sewer pipes, and swales for the flows being calculated by this report. Per the requirements provided by the City of Fort Collins Storm Drainage Design Criteria and Construction Manual, all inlets and storm pipes will be designed to convey the 100-year storm flows. During the major storm event, (developed condition 100- year storm) the accumulated water depth in the water quality/detention ponds will be held to a maximum level of six inches below all building finished floor elevations. FLOODPLAIN REGULATIONS COMPLIANCE As previously stated, the I-25 & Mulberry Commercial Development site is outside of the City of Fort Collins Boxelder Creek flood plain. The City of Fort Collins reanalyzed the Boxelder Creek floodplain and the BFEs (Base Flood Elevations) for Boxelder Creek near the site. Those BFE’s were used for the purposes of this report. CONCLUSIONS COMPLIANCE WITH STANDARDS The hydrologic and water quality calculations were performed using the required methods as outlined in the City of Fort Collins Stormwater Criteria Manual. The proposed drainage improvements meet or exceed the City’s requirements. It should be noted that due to extremely gradual slopes in the existing site conditions (<1%), it is likely that proposed swales, curb & gutter, and surface grades will meet minimum slopes and likely need to incorporate concrete pans in many areas on-site. I-25 & Mulberry Commercial Development Fort Collins ODP Drainage Report 8 REFERENCES Fort Collins Stormwater Criteria Manual; City of Fort Collins, Colorado, December 2018. Urban Storm Drainage Criteria Manual (Volumes 1, 2, and 3); Urban Drainage and Flood Control District, June 2001. I-25 & Mulberry Commercial Development Fort Collins ODP Drainage Report APPENDIX A – FIGURES A Westrian Company VICINITY MAP SITE COOPER SLOUGH BASIN PROPOSED STREAM RESTORATION AND HABITAT IMPROVEMENTS Drake Rd Prospect St Mulberry St 14 I 25 Timberline RdLemay AveLemay AveTimberline RdI 25 14 Vine Dr 0 2,500 5,0001,250 Feet Proposed Stream Restoration and Habitat Improvements Legend Cooper Slough Subbasins Proposed Stream Restoration and Habitat Improvements Proposed Stream Restoration and Habitat Improvements A Westrian Company I-25 AND MULBERRY EXHIBIT A AREA 9: SITE SOUTHERN ULTIMATE OUTFALL VIEW: NORTH AREA 1: 18" CMP VIEW: NORTH AREA 3: 18" RCP VIEW: NORTH AREA 2: VINE INLET VIEW: NORTHWEST AREA 4: RAILROAD CULVERT VIEW: SOUTH AREA 6: DRAINAGE PAN FROM CLOVERLEAF VIEW: SOUTHWEST AREA 8: 24" CULVERT UNDER HWY 14 VIEW: SOUTH AREA 7: ON-SITE AREA INLET VIEW: NORTH AREA 10: SITE EASTERN ULTIMATE OUTFALL AREA 5: CULVERT INTO SITE E HWY 14 E VINE DR MAPLE COTTONWOOD LOCUST BIRCH 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²/DULPHU&RXQW\$UHD&RORUDGR 1DWXUDO5HVRXUFHV &RQVHUYDWLRQ6HUYLFH :HE6RLO6XUYH\ 1DWLRQDO&RRSHUDWLYH6RLO6XUYH\ 3DJHRI 5DWLQJ2SWLRQV $JJUHJDWLRQ0HWKRG'RPLQDQW&RQGLWLRQ &RPSRQHQW3HUFHQW&XWRII1RQH6SHFLILHG 7LHEUHDN5XOH+LJKHU +\GURORJLF6RLO*URXS²/DULPHU&RXQW\$UHD&RORUDGR 1DWXUDO5HVRXUFHV &RQVHUYDWLRQ6HUYLFH :HE6RLO6XUYH\ 1DWLRQDO&RRSHUDWLYH6RLO6XUYH\ 3DJHRI 18,0563,009.3FCMaps Floodplain & FloodwayThis map is a user generated static output from the City of Fort Collins FCMapsInternet mapping site and is for reference only. Data layers that appear on thismap may or may not be accurate, current, or otherwise reliable.City of Fort Collins - GIS2,286.01:WGS_1984_Web_Mercator_Auxiliary_SphereFeet2,286.00 1,143.00NotesLegend13,719FEMA FloodplainFEMA High Risk - FloodwayFEMA High Risk - 100 YearFEMA Moderate Risk - 100 / 500 YearCity FloodplainsCity High Risk - FloodwayCity High Risk - 100 YearCity Moderate Risk - 100 YearCity LimitsWorld Hillshade 400 North Link Lane | Fort Collins, Colorado 80524 Telephone: 970-206-9455 Fax: 970-206-9441 September 21, 2022 Miller United 6900 E Belleview Avenue Suite 300 Greenwood Village, Colorado 80111 Attn: Mr. Steven Shoflick Subject: Piezometer Installation and Groundwater Measurements NE I-25 & Mulberry Fort Collins, Colorado CTL|T Project Number: FC10289-112 CTL|Thompson, Inc. is performing a groundwater monitoring study at the NE I-25 and Mulberry development in Fort Collins, Colorado. This letter presents the most recentgroundwater measurements from the piezometers at this site. On April 8, 2022, eight monitoring holes were drilled at the locations shown on Figure 1 using hollow and solid-stem augers and a truck-mounted drill rig. The monitoring holes were fitted with PVC piezometers to facilitate monthly groundwater measurements. On April 10, 2022, CTL|T began monitoring the piezometers at the site. Table A summarizes our groundwater measurements to date. As of September 19th, 2022, crops present on the site had been harvested. This site activity destroyed piezometers TH-4, TH-5, and TH-7. We appreciate the opportunity to work with you on this project. If you have any additional questions or concerns, please contact the undersigned. Sincerely, CTL|THOMPSON, INC. R.B. “Chip” Leadbetter, III, PE Spencer A. Schram, PE Senior Geotechnical Engineer Geotechnical Project Manager TH-5 TH-4 TH-3 TH-7 TH-2 Mulberry Street / CO-14 Cloverleaf WayTH-8 TH-6 TH-1Interstate 25Frontage RoadPr o po s ed R oa dwa y s MULBERRY STREET CLOVERLEAF WAYI25LEGEND: INDICATES APPROXIMATE LOCATION OF EXPLORATORY BORING TH-1 VICINITY MAP (FORT COLLINS, CO) NOT TO SCALE MILLER UNITED NE I-25 & MULBERRY CTL I T PROJECT NO. FC10289-112 FIGURE 1 Locations of Monitoring Wells 300'150' APPROXIMATE SCALE: 1" = 300' 0' Table ADepth to Groundwater (feet)9/19/228/15/227/11/226/7/225/10/224/11/22TH-17.98.99.29.79.88.3TH-26.98.18.38.97.97.4TH-36.38.28.68.68.67.4TH-4-*7.77.77.88.67.4TH-5-*6.16.05.96.06.2TH-65.65.55.45.55.55.1TH-7-*6.06.06.26.05.6TH-84.55.55.25.55.04.6*Indicates Monitoring Well destroyed by crop harvestCTL | T PROJECT NO. FC10289-112NE I-25 & MULBERRYMILLER UNITED I-25 & Mulberry Commercial Development Fort Collins ODP Drainage Report APPENDIX B – SWMM RESULTS Conduit Surcharge SummaryHoursHours Hours Hours Above HoursBoth Ends Upstream Downstream Normal CapacityConduit Full Full Full Flow Limited24_Out 14.07 14.07 14.07 14.12 14.07SWMM 5Page 1 Link Flow SummaryMaximum Day of Hour of Maximum Max / Max /|Flow| Maximum Maximum |Velocity| Full FullLink Type CFS Flow Flow ft/sec Flow DepthIrr_Ditch1 CONDUIT 6.64 0 03:44 2.39 0.08 0.34Irr_Ditch2 CONDUIT 55.55 0 00:58 3.14 0.18 0.41N_Field CONDUIT 61.36 0 00:47 1.89 0.19 0.42Irr_Ditch3 CONDUIT 61.75 0 00:43 3.85 0.11 0.37Irr_Ditch4 CONDUIT 146.25 0 00:43 3.47 0.40 0.67Irr_Ditch5 CONDUIT 201.26 0 00:45 4.01 0.51 0.75Irr_Ditch6 CONDUIT 250.10 0 00:45 5.30 0.27 0.5824_Out CONDUIT 3.39 0 14:26 2.08 1.08 1.00Out_RR DUMMY 12.72 0 03:44Out_Vine DUMMY 6.64 0 03:29Out_ExPnd DUMMY 14.64 0 03:11Out_Swale DUMMY 5.99 0 03:11MulberryOverflow DUMMY 0.00 0 00:00SWMM 5Page 1 Node Depth SummaryMaximumAverage Maximum Maximum Day of Hour of ReportedDepth Depth HGL Maximum Maximum DepthNode Type Feet Feet Feet Depth Depth FeetNode_1 JUNCTION 0.08 0.67 4964.01 0 03:29 0.67Node_3 JUNCTION 0.11 1.40 4943.50 0 00:47 1.37Node_2 JUNCTION 0.01 1.40 4945.02 0 00:40 1.25Node_4 JUNCTION 0.02 1.53 4945.31 0 00:40 1.42Node_5 JUNCTION 0.04 2.71 4941.37 0 00:42 2.63Node_6 JUNCTION 0.04 3.01 4940.23 0 00:43 2.97Node_7 JUNCTION 0.04 2.99 4937.99 0 00:45 2.99Node_8 JUNCTION 0.64 5.00 4936.50 0 00:21 5.00outfall OUTFALL 0.00 0.00 4930.00 0 00:00 0.00Outfall_2 OUTFALL 0.00 0.00 4930.50 0 00:00 0.00Outfall_3 OUTFALL 0.23 1.50 4932.00 0 00:23 1.50RR STORAGE 0.50 3.22 4946.34 0 03:44 3.22Vine STORAGE 0.30 3.31 4966.65 0 03:29 3.31EXSite STORAGE 0.53 3.48 4932.56 0 03:11 3.48SWMM 5Page 1 Node Flooding SummaryTotal MaximumMaximum Day of Hour of Flood PondedHours Rate Maximum Maximum Volume VolumeNode Flooded CFS Flooding Flooding 10^6 gal 1000 ft³Node_8 14.07 266.40 0 00:45 6.268 0.000SWMM 5Page 1 Node Inflow SummaryMaximum MaximumLateral Total FlowLateral Total Day of Hour of Inflow Inflow BalanceInflow Inflow Maximum Maximum Volume Volume ErrorNode Type CFS CFS Inflow Inflow 10^6 gal 10^6 gal %Node_1 JUNCTION 0.00 6.64 0 03:29 0 2.15 0.000Node_3 JUNCTION 0.00 67.49 0 00:47 0 8 0.000Node_2 JUNCTION 73.95 73.95 0 00:40 1.2 1.2 0.000Node_4 JUNCTION 65.21 65.21 0 00:40 1.15 1.15 0.000Node_5 JUNCTION 91.71 148.18 0 00:42 1.62 2.78 0.000Node_6 JUNCTION 63.35 203.76 0 00:43 1.1 3.88 0.000Node_7 JUNCTION 59.32 251.21 0 00:44 1.06 4.94 0.000Node_8 JUNCTION 27.66 269.54 0 00:45 0.79 7.79 -0.000outfall OUTFALL 0.00 14.64 0 03:11 0 8.88 0.000Outfall_2 OUTFALL 0.00 0.00 0 00:00 0 0 0.000Outfall_3 OUTFALL 0.00 3.39 0 14:26 0 1.52 0.000RR STORAGE 89.54 92.34 0 01:00 4.64 6.79 0.016Vine STORAGE 53.91 53.91 0 00:40 2.15 2.15 0.029EXSite STORAGE 84.46 125.25 0 00:56 2.91 10.9 0.018SWMM 5Page 1 Outfall Loading SummaryFlow Avgerage Maximum TotalFrequency Flow Flow VolumeOutfall Node % CFS CFS 10^6 galoutfall 35.08 7.77 14.64 8.877Outfall_2 0.00 0.00 0.00 0.000Outfall_3 31.79 1.47 3.39 1.523SWMM 5Page 1 Subcatchment Runoff SummaryTotal Total Total Total Imperv Perv Total Total PeakPrecip Runon Evap Infil Runoff Runoff Runoff Runoff RunoffSubcatchment in in in in in in in 10^6 gal CFSEX2 3.67 0.00 0.00 2.43 0.07 1.17 1.24 4.64 89.54EX1 3.67 0.00 0.00 2.57 0.18 0.91 1.09 2.15 53.91EX4 3.67 0.00 0.00 2.19 0.11 1.37 1.48 2.04 47.88EX3 3.67 0.00 0.00 0.80 2.15 0.67 2.82 1.20 73.95EX5 3.67 0.00 0.00 0.95 2.15 0.52 2.67 0.86 38.67EX6 3.67 0.00 0.00 0.84 2.15 0.63 2.78 1.15 65.21EX7 3.67 0.00 0.00 0.84 2.15 0.63 2.78 1.62 91.71EX8 3.67 0.00 0.00 0.96 2.15 0.51 2.66 1.10 63.35EX9 3.67 0.00 0.00 1.11 1.79 0.73 2.52 1.06 59.32EX10 3.67 0.00 0.00 2.41 0.36 0.89 1.25 0.79 27.66SWMM 5Page 1 Subcatchment Runoff SummaryRunoffSubcatchment CoeffEX2 0.338EX1 0.298EX4 0.404EX3 0.770EX5 0.728EX6 0.757EX7 0.757EX8 0.726EX9 0.687EX10 0.341SWMM 5Page 2 Storage Volume SummaryAverage Average Evaporation Exfiltration Maximum Maximum Day of Hour of MaximumStorage Volume Percent Loss Loss Volume Percent Maximum Maximum OutflowUnit 1000 ft³ Full % % 1000 ft³ Full Volume Volume CFSRR 61.543 9 0 0 551.435 81 0 03:44 12.72Vine 13.158 1 0 0 212.109 15 0 03:29 6.64EXSite 44.254 2 0 0 451.713 19 0 03:11 20.63SWMM 5Page 1 Node Inflow SummaryMaximum MaximumLateral Total FlowLateral Total Day of Hour of Inflow Inflow BalanceInflow Inflow Maximum Maximum Volume Volume ErrorNode Type CFS CFS Inflow Inflow 10^6 gal 10^6 gal %Node_4 JUNCTION 58.89 115.55 0 00:42 1.05 2.15 0.000Node_5 JUNCTION 82.82 186.71 0 00:43 1.47 3.62 0.000Node_6 JUNCTION 57.03 234.31 0 00:44 0.987 4.61 0.000Node_7 JUNCTION 59.32 280.55 0 00:45 1.06 5.66 0.00010 JUNCTION 66.21 66.21 0 00:40 1.1 1.1 -0.00011 JUNCTION 0.00 10.26 0 01:10 0 0.605 0.00012 JUNCTION 0.00 10.26 0 01:10 0 0.605 0.00013 JUNCTION 0.00 10.26 0 01:09 0 0.606 0.00014 JUNCTION 0.00 10.26 0 01:11 0 0.604 0.00015 JUNCTION 166.50 166.50 0 00:40 2.79 2.79 0.00018 JUNCTION 22.60 24.98 0 00:40 0.299 0.958 0.00019 JUNCTION 12.21 36.75 0 00:41 0.329 1.29 0.00020 JUNCTION 0.00 4.00 0 00:47 0 0.659 0.00021 JUNCTION 0.00 92.00 0 01:24 0 9.05 0.000MulberryChannel OUTFALL 0.00 36.48 0 00:41 0 1.29 0.000Boxelder OUTFALL 0.00 92.02 0 02:27 0 9.05 0.000PondA STORAGE 39.77 39.77 0 00:40 0.607 0.607 0.174PondC STORAGE 52.68 52.68 0 00:40 0.66 0.66 0.069PondB STORAGE 0.00 432.33 0 00:46 0 9.06 0.101SWMM 5Page 1 Outfall Loading SummaryFlow Avgerage Maximum TotalFrequency Flow Flow VolumeOutfall Node % CFS CFS 10^6 galMulberryChannel 11.45 3.45 36.48 1.286Boxelder 34.96 7.94 92.02 9.048SWMM 5Page 1 Subcatchment Runoff SummaryTotal Total Total Total Imperv Perv Total Total PeakPrecip Runon Evap Infil Runoff Runoff Runoff Runoff RunoffSubcatchment in in in in in in in 10^6 gal CFSEX3 3.67 0.00 0.00 1.05 1.80 0.79 2.58 1.10 66.21EX6 3.67 0.00 0.00 1.11 1.79 0.73 2.52 1.05 58.89EX7 3.67 0.00 0.00 1.11 1.79 0.73 2.52 1.47 82.82EX8 3.67 0.00 0.00 1.25 1.79 0.59 2.38 0.99 57.03EX9 3.67 0.00 0.00 1.11 1.79 0.73 2.52 1.06 59.32EX10 3.67 0.00 0.00 1.84 0.36 1.46 1.82 0.33 12.21B1 3.67 0.00 0.00 0.35 2.87 0.38 3.25 2.79 166.50A1 3.67 0.00 0.00 0.72 2.23 0.67 2.90 0.61 39.77C1 3.67 0.00 0.00 0.49 2.52 0.62 3.13 0.66 52.68EX11 3.67 0.00 0.00 0.69 2.16 0.79 2.94 0.30 22.60SWMM 5Page 1 Subcatchment Runoff SummaryRunoffSubcatchment CoeffEX3 0.704EX6 0.687EX7 0.687EX8 0.649EX9 0.687EX10 0.497B1 0.886A1 0.791C1 0.854EX11 0.802SWMM 5Page 2 Storage Volume SummaryAverage Average Evaporation Exfiltration Maximum Maximum Day of Hour of MaximumStorage Volume Percent Loss Loss Volume Percent Maximum Maximum OutflowUnit 1000 ft³ Full % % 1000 ft³ Full Volume Volume CFSPondA 0.451 0 0 0 31.544 32 0 01:09 10.26PondC 2.001 3 0 0 61.818 80 0 02:07 4.00PondB 12.114 2 0 0 555.306 88 0 01:58 92.00SWMM 5Page 1 Link Flow SummaryMaximum Day of Hour of Maximum Max / Max /|Flow| Maximum Maximum |Velocity| Full FullLink Type CFS Flow Flow ft/sec Flow DepthIrr_Ditch3 CONDUIT 113.73 0 00:44 3.69 0.27 0.56Irr_Ditch4 CONDUIT 185.69 0 00:44 4.19 0.43 0.69Irr_Ditch5 CONDUIT 232.27 0 00:45 3.79 0.67 0.8413 CONDUIT 10.26 0 01:10 4.17 0.50 0.5014 CONDUIT 10.26 0 01:10 4.44 0.46 0.4815 CONDUIT 4.00 0 04:13 3.31 0.11 0.2317 CONDUIT 24.76 0 00:41 5.47 0.46 0.4818 CONDUIT 36.48 0 00:41 5.47 0.55 0.5319 CONDUIT 10.26 0 01:11 4.46 0.28 0.3620 CONDUIT 161.55 0 00:42 5.37 0.50 0.7321 CONDUIT 10.26 0 01:11 8.99 0.10 0.2222 CONDUIT 92.02 0 02:27 16.26 0.74 0.6423 CONDUIT 278.82 0 00:46 3.52 0.28 0.5624 CONDUIT 61.33 0 00:43 3.68 0.30 0.614 DUMMY 4.00 0 00:476 DUMMY 92.00 0 01:248 DUMMY 10.26 0 01:09SWMM 5Page 1 Node Depth SummaryMaximumAverage Maximum Maximum Day of Hour of ReportedDepth Depth HGL Maximum Maximum DepthNode Type Feet Feet Feet Depth Depth FeetNode_4 JUNCTION 0.03 2.26 4939.73 0 00:42 2.18Node_5 JUNCTION 0.04 2.78 4937.85 0 00:43 2.75Node_6 JUNCTION 0.05 3.37 4936.40 0 00:44 3.36Node_7 JUNCTION 0.05 3.40 4934.90 0 00:45 3.4010 JUNCTION 0.02 1.90 4944.10 0 00:40 1.7211 JUNCTION 0.03 1.19 4937.53 0 01:10 1.1912 JUNCTION 0.03 1.25 4937.91 0 01:10 1.2513 JUNCTION 0.03 1.25 4938.25 0 01:09 1.2514 JUNCTION 0.03 1.08 4936.24 0 01:11 1.0815 JUNCTION 0.03 2.23 4938.23 0 00:40 2.1018 JUNCTION 0.05 1.69 4933.57 0 00:40 1.4619 JUNCTION 0.05 1.68 4933.18 0 00:41 1.4820 JUNCTION 0.04 0.68 4934.18 0 00:47 0.6821 JUNCTION 0.11 2.87 4933.37 0 01:24 2.87MulberryChannel OUTFALL 0.03 1.05 4931.55 0 00:41 0.96Boxelder OUTFALL 0.11 2.87 4929.68 0 02:27 2.87PondA STORAGE 0.03 1.80 4938.80 0 01:09 1.79PondC STORAGE 0.11 2.67 4936.17 0 02:07 2.67PondB STORAGE 0.17 5.66 4936.16 0 01:58 5.66SWMM 5Page 1 Subdivision:0Project Name:1-25 & MulberryLocation:Fort CollinsProject No.:39737.01By:AJHVolume=1/3 x Depth x (A+B+(A*B)^0.5)Checked By:0A - Upper SurfaceDate:9/30/22B - Lower SurfaceStage Stage Elevation Stage Surface Area Stage Volume Cumulative Volume Cumulative Volume(square feet) (cubic feet) (cubic feet) (acre feet)0.00 4930.50 200 0 0 0.001.00 4931.00 1,085 584 584 0.012.00 4932.00 30,721 12,526 13,110 0.303.00 4933.00 106,618 64,856 77,966 1.794.00 4934.00 186,834 144,862 222,828 5.125.00 4935.00 202,308 194,518 417,346 9.585.50 4935.50 208,879 102,791 520,137 11.94POND VOLUME CALCULATIONSPOND BX:\3970000.all\3978900\Excel\Drainage\3978900 Existing Calcs.xlsmPage 1 of 2 10/3/2022 Subdivision:0Project Name:1-25 & MulberryLocation:Fort CollinsProject No.39737.01By:AJHChecked By:0Date:9/30/22POND VOLUME CALCULATIONS4930.004931.004932.004933.004934.004935.004936.00-2.00 0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00Elevation (ft)Pond Volume (ac-ft)Pond Stage-StorageX:\3970000.all\3978900\Excel\Drainage\3978900 Existing Calcs.xlsmPage 2 of 2 10/3/2022 Subdivision:0Project Name:1-25 & MulberryLocation:Fort CollinsProject No.:39737.01By:AJHVolume=1/3 x Depth x (A+B+(A*B)^0.5)Checked By:0A - Upper SurfaceDate:9/30/22B - Lower SurfaceStage Stage Elevation Stage Surface Area Stage Volume Cumulative Volume Cumulative Volume(square feet) (cubic feet) (cubic feet) (acre feet)0.00 4933.50 50 0 0 0.001.00 4934.00 18,463 6,491 6,491 0.152.00 4935.00 33,906 25,796 32,287 0.742.50 4935.50 42,204 37,979 51,277 1.18POND VOLUME CALCULATIONSPOND CX:\3970000.all\3978900\Excel\Drainage\3978900 Existing Calcs.xlsmPage 1 of 2 9/30/2022 Subdivision:0Project Name:1-25 & MulberryLocation:Fort CollinsProject No.39737.01By:AJHChecked By:0Date:9/30/22POND VOLUME CALCULATIONS4933.004933.504934.004934.504935.004935.504936.000.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40Elevation (ft)Pond Volume (ac-ft)Pond Stage-StorageX:\3970000.all\3978900\Excel\Drainage\3978900 Existing Calcs.xlsmPage 2 of 2 9/30/2022 Subdivision:0 Project Name:1-25 & Mulberry Location:Fort Collins Project No.:39737.01 Calculated By:AJH Checked By:0 Date:9/30/22 Basin Area (ac)% Imp. A 31.65 80.0% Total 31.65 80.0% WQCV Drain Time (hr):40 Coefficient, a (Table 3-2):1.0 WQCV (in):0.33 WQCV (ac-ft):0.87 Detention Pond Tributary Areas POND B X:\3970000.all\3978900\Excel\Drainage\3978900 Existing Calcs.xlsm Page 1 of 1 9/30/2022 Subdivision:0 Project Name:1-25 & Mulberry Location:Fort Collins Project No.:39737.01 Calculated By:AJH Checked By:0 Date:9/30/22 Basin Area (ac)% Imp. C1 7.75 70.0% Total 7.75 70.0% WQCV Drain Time (hr):40 Coefficient, a (Table 3-2):1.0 WQCV (in):0.28 WQCV (ac-ft):0.18 Detention Pond Tributary Areas POND C X:\3970000.all\3978900\Excel\Drainage\3978900 Existing Calcs.xlsm Page 1 of 1 9/30/2022 Subdivision:0Project Name:1-25 & MulberryLocation:Fort CollinsProject No.:39737.01By:AJHVolume=1/3 x Depth x (A+B+(A*B)^0.5)Checked By:0A - Upper SurfaceDate:9/30/22B - Lower SurfaceStage Stage Elevation Stage Surface Area Stage Volume Cumulative Volume Cumulative Volume(square feet) (cubic feet) (cubic feet) (acre feet)0.00 4937.00 0 0 0 0.001.00 4938.00 20,391 6,797 6,797 0.162.00 4939.00 36,614 28,109 34,906 0.802.50 4939.50 38,202 37,405 72,311 1.66POND VOLUME CALCULATIONSPOND AX:\3970000.all\3978900\Excel\Drainage\3978900 Existing Calcs.xlsmPage 1 of 2 9/30/2022 Subdivision:0Project Name:1-25 & MulberryLocation:Fort CollinsProject No.39737.01By:AJHChecked By:0Date:9/30/22POND VOLUME CALCULATIONS4936.504937.004937.504938.004938.504939.004939.504940.000.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80Elevation (ft)Pond Volume (ac-ft)Pond Stage-StorageX:\3970000.all\3978900\Excel\Drainage\3978900 Existing Calcs.xlsmPage 2 of 2 9/30/2022 I-25 & Mulberry Commercial Development Fort Collins ODP Drainage Report APPENDIX C – HYDRAULIC CALCULATIONS Culvert Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc.Wednesday, Sep 28 2022 24Inch CPP EX Outfall Invert Elev Dn (ft) = 4927.28 Pipe Length (ft) = 366.00 Slope (%) = 0.49 Invert Elev Up (ft) = 4929.08 Rise (in) = 24.0 Shape = Circular Span (in) = 24.0 No. Barrels = 1 n-Value = 0.013 Culvert Type = Circular Corrugate Metal Pipe Culvert Entrance = Mitered to slope (C) Coeff. K,M,c,Y,k = 0.021, 1.33, 0.0463, 0.75, 0.7 Embankment Top Elevation (ft) = 4948.00 Top Width (ft) = 135.00 Crest Width (ft) = 20.00 Calculations Qmin (cfs) = 5.00 Qmax (cfs) = 50.00 Tailwater Elev (ft) = 0.00 Highlighted Qtotal (cfs) = 23.00 Qpipe (cfs) = 23.00 Qovertop (cfs) = 0.00 Veloc Dn (ft/s) = 8.06 Veloc Up (ft/s) = 7.32 HGL Dn (ft) = 4928.99 HGL Up (ft) = 4932.83 Hw Elev (ft) = 4934.25 Hw/D (ft) = 2.58 Flow Regime = Outlet Control Culvert Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Wednesday, Sep 28 2022 48 Inch Pond C Outfall Invert Elev Dn (ft) = 4927.50 Pipe Length (ft) = 1010.00 Slope (%) = 0.30 Invert Elev Up (ft) = 4930.50 Rise (in) = 48.0 Shape = Circular Span (in) = 48.0 No. Barrels = 1 n-Value = 0.013 Culvert Type = Circular Concrete Culvert Entrance = Square edge w/headwall (C) Coeff. K,M,c,Y,k = 0.0098, 2, 0.0398, 0.67, 0.5 Embankment Top Elevation (ft) = 4936.00 Top Width (ft) = 1000.00 Crest Width (ft) = 20.00 Calculations Qmin (cfs) = 40.00 Qmax (cfs) = 150.00 Tailwater Elev (ft) = (dc+D)/2 Highlighted Qtotal (cfs) = 88.00 Qpipe (cfs) = 88.00 Qovertop (cfs) = 0.00 Veloc Dn (ft/s) = 7.69 Veloc Up (ft/s) = 7.00 HGL Dn (ft) = 4930.92 HGL Up (ft) = 4934.74 Hw Elev (ft) = 4935.14 Hw/D (ft) = 1.16 Flow Regime = Inlet Control I-25 & Mulberry Commercial Development Fort Collins ODP Drainage Report APPENDIX D – MAPS A Westrian Company I-25 & MULBERRY - OVERALL DEVELOPMENT PLANFORT COLLINS, COLORADOPOND A - 1.66 AC-FTINV: 4937.00POND B - 11.72 AC-FTINV: 4930.50POND C - 1.20 AC-FTINV: 4933.50MULBERRY STREETCLOVERLEAF WAYEX FRONTAGE RDMAPLECOTTONWOODLOCUSTBIRCHI-25ASPENWILLOWOFFSITE FLOW:12.7 CFSOFFSITE FLOW:54.8 CFSCUMULATIVE OFFSITE FLOWCLOVERLEAF:251.0 CFSSPRUCE LNFRONTAGE ROAD (COLLECTOR) A Westrian Company I-25 & MULBERRY - ODP EXISTING CONDITIONS CONCEPTUAL DRAINAGE EXHIBIT MULBERRY STREETI-25CLOVERLEAF WAYNE FRON T A G E R D MAPLE COTTONWOOD LOCUST BIRCH SPRUCE RAILROAD TRACKSI-25I-25HWY 14 E VINE DR B D INADVERTENT DETENTION INADVERTENT DETENTION INADVERTENT DETENTION A C