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HomeMy WebLinkAboutReports - Erosion Control - 11/19/2025 Stormwater Management Plan (Erosion Control Report) Fort Collins Southeast Community Center Rock Creek Drive Fort Collins, CO 80528 November 19, 2025 CE Project No.: 326-034-24 Prepared by: 123 N College Avenue, Suite 200 Fort Collins, CO 80524 970.818.8999 clarkenersen.com Engineer of Record: Shane Boyle, PE Prepared for Owner: The City of Fort Collins 222 LaPorte Avenue, Fort Collins, Colorado 80521 Contractor: GH Phipps Construction 4800 Innovation Drive Fort Collins, Colorado 80525 Engineer Certification of Erosion Control Report Shane Boyle, P.E. Registered Professional Engineer State of Colorado No. 40185 Contents SWMP Objectives 2 Project Description and Nature of Construction 3 Project Location 3 Existing Site Conditions 4 Proposed Construction Activities 4 Important Site Volumes 5 Potential Pollutant Sources 6 Construction Control Measures 8 Temporary Control Measures 8 Permanent Control Measures 10 Erosion control Sequencing 10 Sequence 1 – Initial Erosion Control Measures 10 Sequence 2 – Interim Erosion Control Measures 11 Sequence 3 – Final Erosion Control Measures 12 Maintenance and Inspection Requirements 12 Final Vegetation and Stabilization 13 References 13 APPENDIX A. 14 Erosion Control Plans 14 APPENDIX B. 15 Drainage Plans 15 2 SWMP OBJECTIVES The objective of the Stormwater Management Plan (SWMP) for the Fort Collins Southeast Community Center is to determine the Best Management Practices (BMP’s) which will be implemented on the project site to effectively limit and/or eliminate the amount of sediment leaving the site during construction activities. The chosen BMP’s will meet the requirements of the Colorado Department of Public Health & Environment, Water Quality Control Division. According to Appendix A of the State of Colorado General Permit Application and Stormwater Management Plan Guidance for Stormwater Discharges Associated with Construction Activity (2019) and the City of Fort Collins Storm Drainage Design Criteria, the SWMP goal is to, “describe appropriate controls and measures to improve water quality by reducing pollutants in storm water discharges and ensure compliance with the requirements of the storm water permit. The SWMP must be completed and implemented at the time the project breaks ground, and revised, if necessary, as construction proceeds to accurately reflect the conditions and practices at the site.” During the construction process, the SWMP is a “living” document that can and will be modified and updated as construction activities take place. The SWMP should reflect all current site conditions at all times. The SWMP document shall be kept on site at all times with all updates and changes. A SWMP Administrator will be responsible for, but not limited to, inspections and inspection reports, personnel training, regulatory agency contact, field notebooks, SWMP implementation and revisions, and record keeping of employee activities, contacts, and notifications. Pollutant sources should be evaluated continuously and proper BMP’s should be selected, documented, and implemented as site conditions change throughout the course of construction. 3 PROJECT DESCRIPTION AND NATURE OF CONSTRUCTION Project Location The Fort Collins Southeast Community Center (referred herein as “the site”) is located on the southeast corner of Ziegler Road and Rock Creek Drive, directly west of Fossil Ridge High School. The site is located within the west line of the southwest quarter of section 4, township 6 north, range 68 west of the 6 th Principal Meridian in the City of Fort Collins, County of Larimer, State of Colorado. The site is located on parcel number 8604000933 with coordinates of 40.51499° N,105.01886° W. Image 1 shows a vicinity map of the parcel. Image 1. Aerial Image (Google Earth July 2025) PROJECT LOCATION ROCK CREEK DRIVE ZI E G L E R R O A D 4 Existing Site Conditions The site is currently undeveloped and in its natural condition of natural grasses and weeds. There are no structures or infrastructure located on the site and has only been used for agriculture in the past. Below is a breakdown of the existing conditions: Soil Type – According to the Natural Resources Conservation (NRCS) web soil survey and report, the site is composed 100% of nunn clay loam, 0 to 1 percent slopes. Grades – Most of the site has a slope of 5% or less. On the south side of the site there is a depression that has maximum slopes of 13%-14%. Ground Cover – The site had previously been used for agricultural purposes prior to 1999. The site has not been used since then and is now covered with natural grasses and weeds. Utilities – The site currently does not have any existing utilities on the property. All utilities currently have infrastructure in the adjacent streets and will be brought into the site. Storm Drainage / Irrigation Facilities – The site currently does not have any existing storm drainage infrastructure or irrigation facilities. Both storm drainage and irrigation will be connected to existing infrastructure in the adjacent streets. A geotechnical report was completed for the site and the results showed existing clayey sand and sandy clay underlain by claystone bedrock that was encountered at depths ranging from 19’ to 28’ depending on the test hole. Groundwater was found at depths ranging from 15’ to 18’ and are not suspected to be an issue for the proposed project. The site is approximately 10.4 acres located to the southeast of Ziegler Road and Rock Creek Drive. The current drainage pattern generally surface flows to the southeast. The closest receiving water is McClelland’s Creek and is approximately 0.25 miles away via existing storm sewer pipe infrastructure. Proposed Construction Activities This project will disturb approximately 10.4 acres of the property owned by the City of Fort Collins. The project will all be completed at once and there will not be phases as part of this project. Construction activities will take place on-site only; there will be no off-site disturbance. Before any construction is to take place, BMPs will be placed where needed. Once BMPs are in place, the initial clearing, grubbing, and overlot grading will be completed. Once the overlot grading has been done, the proposed utilities will be installed. The proposed utilities include an underground storm sewer system (pipe, manholes, inlets, and water quality control features), sanitary sewer mains and services, water/fire line mains and services, underground electric, gas lines, and fiber optic lines. After utilities are installed, construction of the building, parking lot, curb and gutter, sidewalks, and detention pond will occur. When construction activities conclude, the remaining disturbed 5 areas on the site will be seeded to help reduce any potential erosion and transportation of sediment from the site. Here is a list of the main construction aspects in the order of occurrence for the project: 1) Erosion control measures are installed where needed. 2) The site is cleared and grubbed. 3) Any extra topsoil is removed and stockpiled. 4) Grading for entire site is done, including the detention pond along the west and south sides of the site. 5) Any additional erosion control measures are installed for the detention pond or current ones are maintained. 6) Utilities are installed with open trenching and connections to existing utilities are made. 7) Additional erosion control measures are installed for storm sewer facilities and maintenance of existing control measures is done. 8) The subgrade is prepped and final grading of the site is completed to prepare for building pads and hard surfaces. 9) Concrete curb and gutter, drainage pans, sidewalks, concrete pads, pathways, asphalt paving, and building foundation is installed. 10) Once hard surfaces are installed, more erosion control measures are implemented to control change in drainage paths and current erosion control measures are maintained. 11) Installation of project lighting and striping in the parking lot is completed. 12) Landscaping will then be completed including plants, trees, and sod. Any disturbed areas not to be landscaped per the landscape plan will be seeded for revegetation efforts to help stabilize the ground and minimize erosion. 13) Any erosion control measures that will be permanent on the site will then be installed and temporary erosion control measures will be removed. 14) Final site clean up will occur and any punch list items will be addressed. There are not any environmental impacts to surrounding properties expected during the course of construction. A Stormwater Management Plan (SWMP) Permit will be required through the State of Colorado before any construction activities take place. Important Site Volumes The table below shows cut and fill volumes for the entirety of the project. Total Site Area Staging/Stockpiling Existing Imperviousness Cut (CY) Fill (CY) Net (CY) 10.4 AC 1.0 AC 0% 7,405 26,642 19,237 6 POTENTIAL POLLUTANT SOURCES Below is a list of potential pollutant sources that are expected on the site as well as means and methods to contain and eliminate chances of these sources being transported off site and to downstream receiving waters. 1) Disturbed and stored soils: The soils stockpiled from grading and the utility excavation and topsoil stockpiles will be stored in the designated area for the duration of the project. These stockpiles shall not exceed 10’ in height and will be located at least 50’ from any proposed or existing storm sewer inlets as well as the proposed on- site detention pond. These stockpiles shall be seeded if they are to remain for longer than 30 days. Silt fence or straw waddles shall be installed around the perimeter of the stockpiles in order to prevent rainfall events from transporting sediment away from the stockpiles. To prevent heavy erosion, any disturbed areas of the site shall be surface roughened. The proposed stockpiling / staging location will be determined on-site and drawn on the SWMP plans part of the interim sequence of erosion control measures. 2) Vehicle tracking of sediments: A vehicle tracking control pad will be required at the entrance to the site during construction activities to reduce tracking sediment onto the adjacent streets. It is anticipated for the construction access for the property to be from Ziegler Road. At the end of each day, the contractor shall sweep Ziegler Road of sediment that may have accumulated throughout the work day. 3) Management of contaminated soils: If the contractor encounters contaminated soils during the construction process, they shall stop construction immediately and notify the appropriate government authorities in accordance with good construction safety and practice. There are not any known contaminated soils on the site. 4) Loading and unloading operations: There will be loading and unloading taking place on the site. Truck access shall be limited to the disturbed areas on the site as much as possible. BMPs shall be installed in all necessary places to minimize sediment leaving the site. 5) Outdoor storage of construction materials, building materials, fertilizers, and chemicals: Onsite material storage, including building materials, fertilizers, and chemicals, will be covered and placed on pallets to prevent direct contact with the ground and potential surface runoff. 6) Bulk storage of materials: There will be no bulk storage of materials on site for this project. 7) Vehicle and equipment maintenance and fueling: 7 Vehicle and equipment maintenance shall not be performed on adjacent public streets. If possible, vehicle and equipment maintenance shall occur off site. If maintenance must occur on site, it shall be performed on the hard surface or gravel areas at least 50’ from any stormwater feature (curb inlets, storm sewer system, swales, water quality, etc.). 8) Significant dust or particulate generating processes: The contractor shall comply with all applicable City of Fort Collins air pollution control requirements. The contractor shall take all applicable actions to minimize atmospheric pollution and take reasonable precautions which include, but are not limited to: a. Using water to control dust for construction processes such as demolition, grading, and grubbing of the land. b. Open-bodied trucks transporting materials being covered when in motion to minimize airborne dust. c. Require lower speeds for all vehicles entering, exiting, and driving within the project limits in order to reduce the amount of dust being disturbed by moving vehicles. 9) Routine maintenance activities involving fertilizers, pesticides, detergents, fuels, solvents, and oils: All fertilizers, pesticides, detergents, fuels, solvents, and oils will be stored in watertight containers and covered as necessary. These items will be stored in a bermed area, storage building, or in a vehicle to serve as secondary containment. 10) On-site waste management practices: Any solid waste materials shall go in the on-site dumpster that has a cover. These dumpers will be emptied and trucked off site periodically during construction activities. Waste piles shall be surrounded or covered by silt fence or straw waddles at all times. Liquid waste shall be in covered containers and disposed of properly. 11) Concrete truck/equipment washing, including the concrete truck chute and associated fixtures and equipment: There will be a dedicated washout area within the disturbed area of the project site. The contractor shall use this washout area only and make sure no runoff is able to leave the site and enter adjacent streets, storm sewers, etc. 12) Dedicated asphalt and concrete batch plants: There will be no dedicated asphalt or concrete batch plants on this project. 13) Non-industrial waste sources such as worker trash and portable toilets: Worker trash shall be disposed of in on-site dumpers and the site shall have no trash at the end of each work day. Portable toilets shall only be used by construction personnel and are to be maintained regularly. Portable toilets must be a minimum of 5’ from the curb and at least 50’ away from any storm sewer inlet. If they are placed on a hard surface, a containment pan or secondary containment BMP must be in place. All portable toilets must be anchored down, regardless of location, per manufacturers recommendations. 8 14) Saw cutting and grinding: Tie into existing utilities shall be the only time saw cutting and/or grinding will be done. The tie ins will occur in city ROW, not on the project site. Water suppression should be used to reduce transport of dust and any loose material shall be removed and disposed of off-site. 15) Non-storm water discharge: Any non-storm water discharge, including, but not limited to, irrigation to establish seeding and waterline flushing. The contractor shall manage this runoff using BMP’s mentioned in this report (i.e. straw waddles, silt fence, concrete washout areas, surface roughening, etc.) CONSTRUCTION CONTROL MEASURES Best Management Practices (BMPs) are put in place before, during, and after construction to minimize sediment leaving the site. The BMPs are to be inspected and maintained on a daily basis during the course of construction activities. The erosion control maps in Appendix A shows where the BMPs will be installed and at what point during construction. The following temporary and permanent BMPs will be used on this project to control on-site erosion and prevent sediment from leaving the site during construction. Temporary Control Measures  Inlet Protection – Helps prevent sediment, soil, and debris from the site to enter the storm drain inlets. These consist of a sediment filter around an inlet and/or upstream of an inlet. Storm water flows through the inlet protection to the drain but any debris, sediment, or soil is filtered out. Both proposed and existing storm sewer inlets shall have inlet protection at the time the construction occurs.  Silt Fence – A woven synthetic permeable fabric fence that filters runoff from the site. Silt fence shall be installed before any construction activities occur. The site perimeter, where applicable, shall have silt fence. Most importantly, it is placed downstream of areas where runoff is expected to happen from construction activities. Silt fence will be installed per manufacturer’s recommendations. Silt fence is to be used in areas of sheet flow, not concentrated flow. In places of concentrated flow, alternative BMPs will be used to help minimize sediment leaving the site.  Staging Areas – Area to perform vehicle fueling, concrete truck washout, material storage and transfer, equipment maintenance and cleaning, and any other construction activities will be provided a minimum of 100’ from any storm water conveyance. These areas will be maintained and isolated that will allow for contaminants to be concentrated in one area and removed from the site as necessary. The concrete washout area shall be designed so washout water cannot leave the location, nor shall storm water runoff wash concrete from the location. 9  Straw Wattles – Used for inlet protection, curbside check dams, swale protection, bottom of slopes, and limits of property boundaries. Straw wattles consist of a netted “tube” filled with straw, excelsior, or coconut fiber that helps filter sediment and debris from the runoff so sediment is not leaving the site. Straw wattles require proper installation and maintenance to ensure their performance.  Rock Socks – Similar to straw wattles, rock socks are used for inlet protection, curbside check dams, or the limits of property boundaries. Rock socks are wire “tubes” filled with rocks and require proper installation and maintenance to ensure their performance.  Check Dams – Used in drainage channels as grade control structures to help minimize erosive nature of stormwater by lowering flow velocity. Check dams require proper installation and maintenance to ensure their performance.  Street Sweeping – Sediment that has tracked out onto roadways are to be removed using street sweeping at the end of each day. The main reason to street sweep is to ensure sediment doesn’t get washed into the storm drain systems. All paved roads surrounding the project site should be inspected at least once a day, if not more frequently.  Saw Cutting Pollution Prevention – Dust from concrete saw cutting and asphalt cutting can migrate into existing storm sewer systems. All slurry and cuttings shall be vacuumed during saw cutting activities and shall not be left on pavement surface overnight. The vacuumed debris shall be disposed of properly to ensure it does not enter storm sewer systems.  Surface Roughening – Performed to help minimize wind erosion on the project site. When slopes are created on site, a technique is used to “groove” the slope to help reduce erosion potential by decreasing runoff velocities, reducing the length of sheet flow trapping sediment, and increasing filtration of water into the soil.  Temporary Seeding – Vegetative cover will be put down on any graded area exposed for longer than 30 days. Usually used on areas that will get permanent vegetation later in the project, the seed mix is 100% smooth brome at a minimum application rate of 30 pls/lbs/acre. Reference the plans for fertilizer and mulch that shall be included in the temporary seeding process.  Vehicle Tracking Control Pad – Any entry and exit used for construction activity purposes shall have a vehicle tracking control pad to help minimize the amount of sediment leaving the site and deposited on adjacent streets from vehicles/trucks. Any stockpile area exits will also have a vehicle tracking pad to help minimize tracking mud around the site.  Dust Control and Wind Borne Sediment Control – During the grading process, water will be applied to the disturbed soil to help minimize the dust and sediment put into the air. This will also help with moisture requirements for compaction of the disturbed soils. 10 Permanent Control Measures  Grass-Lined Swales – Used to channel water to the detention pond, grass-lined swales help infiltration to occur and lowers the velocity of storm water runoff. With a lower velocity, the occurrence of erosion is lessened as well.  Permanent Seeding and Planting – Trees, shrubs, vines, grass/sod, or legumes are part of the permanent stabilization of the ground by holding the soil in place. The purpose of permanent landscaping is to promote infiltration of runoff, maintains sheet flow, reduces storm water runoff velocity, protects the soil surface from erosion, and improves wildlife habitat.  Water Quality Outlet Structure – Placed at the outlet of the detention pond, this allows water to be filtered before entering the larger storm sewer system and minimizing any sediment going into local bodies of water. EROSION CONTROL SEQUENCING Erosion control measures for the project will be implemented in 3 main sequences, initial, interim, and final. The initial sequence BMPs will be installed before any construction activities occur on-site. The interim sequence BMPs will be implemented throughout the course of construction activities as needed. The final sequence BMPs will include all permanent erosion control measures needed for the site that have not been installed in the initial or interim sequences. Erosion control sequence maps can be found in the Appendix and details which sequence each BMP falls under. Certain BMPs are not drawn on the SWMP maps and will be required by the contractor to draw them in on-site where they are located during the construction process. Sequence 1 – Initial Erosion Control Measures  Silt Fence – The perimeter of the construction site will have silt fence installed where able. The most important areas are downstream areas where runoff from construction activities are expected to occur.  Staging Area – Concrete washout area, fueling area, and other staging areas will need to be at least 100’ from any storm water conveyance and must be drawn on the SWMP maps when location is determined on-site.  Vehicle Tracking Control Pad – To be placed at any and all construction entrances and exits on the construction site as well as at the exit of any staging areas. 11  Construction Fence – To be placed at the contractor’s discretion to limit access to construction equipment and personal vehicles for public safety.  Staging/Stockpiles – Area where excess topsoil will be stockpiled will need to be designated on the SWMP maps on-site when area is determined. This area also must be surrounded by silt fence and/or straw wattles.  Inlet Protection – All existing storm sewer inlets shall have inlet protection to minimize sediment from construction to enter the existing storm sewer. These include any inlets on the adjacent roadways that might receive any surface runoff from the project site. Sequence 2 – Interim Erosion Control Measures All erosion control measures installed in sequence 1 shall remain in place and be functional during the course of construction activities. The following erosion control measures shall be installed in addition to those previously mentioned in sequence 1.  Wind Borne Sediment and Dust Control – During grading activities, water shall be placed on soil to minimize wind borne sediment and dust kicking up into the air.  Inlet Protection – Straw wattles will be placed at all storm sewer curb inlets immediately after the inlets have been installed.  Swale Protection – Straw wattles and check dams need to be implemented in the swale immediately after rough grading has occurred.  Slope Protection – Once rough grading is done, surface roughening shall be done to protect slopes from erosion.  Temporary Seeding – If disturbed areas are to be left exposed for 30 days or more, temporary seeding is required.  Outlet Protection – This will need to be placed immediately downstream of any and all storm sewer outfalls.  Concrete Washout Area – A location for the concrete washout area will be designated on-site and will need to be maintained for the entire duration of the project. 12 Sequence 3 – Final Erosion Control Measures Some erosion control measures from sequences 1 and 2 may still be in place until permanent seeding is at 70% density of pre-existing natural vegetation. Other erosion control measures will have been removed if they are not needed anymore (i.e. vehicle tracking control pad since the paving will be completed).  Permanent Seeding – Landscaping shall be placed immediately in areas that are final graded and should not be disturbed by continued construction work. This will limit the amount of erosion in most areas. MAINTENANCE AND INSPECTION REQUIREMENTS The temporary control measures will be inspected and documented by the SWMP administrator at a minimum of once every 14 days and after each precipitation or snowmelt event. The SWMP will be kept up-to-date with inspection records, maintenance procedures, and changes as the project progresses. Records should include complete inspection reports for each inspection, maintenance, and/or repair. A record-keeping system is recommended in managing inspection and maintenance reports and should include all maintenance records, spill responses, weather conditions, training, and correspondence. Equipment maintenance is included in preventative maintenance and should also be included in regular inspection and testing. Records of this maintenance and inspections shall be recorded and made available upon request. Areas that must be included in observation are the construction site perimeter, runoff discharge points, disturbed areas, staging areas, concrete washout areas, fueling areas, erosion and sediment control measures identified in the SWMP plans, and any other structural BMPs that may require maintenance. If the inspection determines there is evidence of or potential for pollutants to enter the storm sewer system, they must be modified, replaced, or added to immediately. Some recommended maintenance procedures include, but are not limited to:  Areas where vehicles enter and/or exit the site shall be inspected for evidence of sediment being tracked off the project site by construction vehicles. This sediment should be cleaned up by sweeping the roadway before it can be conveyed to any receiving storm water systems or local receiving waters.  Erosion control measures are to be inspected and any that are found to be in need of maintenance or repair shall be maintained or repaired as soon as practical. It is necessary to maintain effectiveness of any and all erosion control measures.  Seeded areas will need to be checked to ensure that grass coverage is maintained by watering, fertilizing and reseed as needed. 13 FINAL VEGETATION AND STABILIZATION The site has been deemed vegetated and stabilized when all soil disturbing activities on the project site have been completed and at least 70% of pre-disturbance levels of vegetation have been achieved. Once final stabilization has been met, all temporary BMPs can be removed and properly disposed of. The final landscape details can be found on the landscape plans and need to be implemented before final stabilization has been attained. REFERENCES  City of Fort Collins Stormwater Criteria Manual, as adopted by the City Council of the City of Fort Collins, as referenced in Section 26-500 of the Code of the City of Fort Collins, Revised December 2018.  State of Colorado, Stormwater Discharges Associated with Construction Activity, Stormwater Management Plan Preparation Guides, www.colorado.com.  Urban Storm Drainage Criteria Manuals 2 and 3, Urban Drainage and Flood Control District, Denver, Colorado, November 2010 as currently (February 2018) amended. 14 APPENDIX A. Erosion Control Plans I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R IRR IRR IRR IRR IRR IRR IRR I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R IR R IR R I R R FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S UGE UGE UGE UGE UGE UGE UGE UGEUGEUGE UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UGE UGE UG E UG E UGE UGE UG E UG E UG E UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE D D S S OH E OH E OH E OH E OH E OH E OH E OH E OH E OH E OH E SSSSSS SS SS SS SS SS SS SS SS SS SS SS SS SS STOP MB D D IRR IRR I R R I R R I R R IR R IRR UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UGE UGE ZI E G L E R R O A D ROCK CREEK DRIVE 4919 4920 4921 49 2 2 49 2 3 49 2 4 49 1 9 4919 4920 4921 4918 4919 492 0 4921 49 1 5 4916 4917 49 1 8 491 9 49 2 0 49 2 1 491 6 49 1 7 49 1 8 49 1 9 49 2 0 49 2 1 49 2 2 49 1 4 49 1 4 49 1 5 49 1 5 49 1 6 49 1 6 491 7 49 1 7 49 1 8 49 1 8 491 8 491 9 49 2 0 49 2 1 PROPERTY LINE PROPERTY LINE PROPERTY LINE VEHICLE TRACKING CONTROL CONCRETE WASHOUT S F S F S F S F S F S F S F S F S F SF SF SF SF SF SF SF SF SF S F S F S F S F S F S F SF SF SF SF SF SF SF SF SF S F S F S F S F S F S F S F SF SILT FENCE LIMITS OF GRADING SILT FENCE LIMITS OF GRADING PROPERTY LINE SEDIMENT TRAP SCOURSTOP (TYP.) CE No.: 11 / 1 8 / 2 0 2 5 8 : 3 9 : 2 0 A M Pl o t T i m e S t a m p : DRAFT PREPARED FOR PRELIMINARY SUBMISSION AND REVIEW ONLY -- NOT FOR CONSTRUCTION. \\ c e - c o - s r v - 0 0 4 \ 3 0 0 - 3 9 9 \ 3 2 6 - 0 3 4 - 2 4 F o C o S o u t h e a s t C o m m u n i t y C e n t e r \ 0 3 ) A u t o C A D \ 3 2 6 0 3 4 - C 3 . 1 0 - E r o s i o n C o n t r o l . d w g Fi l e L o c a t i o n / N a m e : Architecture Engineering Planning Landscape Architecture Commissioning clarkenersen.com Kansas City, Missouri Lincoln, Nebraska Lawrence, Kansas Portland, Oregon Fort Collins, Colorado Omaha, Nebraska Charleston, South Carolina PDP/FDP Submittal - Round 1 Southeast Community Center Rock Creek Dr & Ziegler Rd Fort Collins, CO 80528 326-034-24 11/19/2025 Initial Erosion Control Plan C3.10SCALE: 1" = 50' INITIAL EROSION CONTROL PLAN 0'25'50'100' PROPOSED CONTOUR EXISTING CONTOUR APPROXIMATE LIMITS OF GRADING LEGEND EROSION CONTROL - SILT FENCE SF SF FLOWLINE MH MH MH MH MH MH MH MH MH MH FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S UGE UGE UGE UGE UGE UGE UGE UGEUGEUGE UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UGE UGE UG E UG E UGE UGE UG E UG E UG E UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE D D S S OH E OH E OH E OH E OH E OH E OH E OH E OH E OH E OH E SSSSSS SS SS SS SS SS SS SS SS SS SS SS SS SS STOP MB D D UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UGE UGE ZI E G L E R R O A D ROCK CREEK DRIVE 4921 4921 49 1 5 49 1 8 4916 4920 4922 49 2 1 49 2 0 49 1 6 4915 4917 4919 4916 4918 49 1 4 49124914 4916 4914 4917 49 1 9 492 0 49 1 8 4919 4920 4921 49 2 2 49 2 3 49 2 4 49 1 9 4919 4920 4921 4918 4919 492 0 4921 49 1 5 4916 4917 49 1 8 491 9 49 2 0 49 2 1 491 6 49 1 7 49 1 8 49 1 9 49 2 0 49 2 1 49 2 2 49 1 4 49 1 4 49 1 5 49 1 5 49 1 6 49 1 6 491 7 49 1 7 49 1 8 49 1 8 491 8 491 9 49 2 0 49 2 1 PROPERTY LINE PROPERTY LINE PROPERTY LINE VEHICLE TRACKING CONTROL CONCRETE WASHOUT IP S F S F S F S F S F S F S F S F S F SF SF SF SF SF SF SF SF SF S F S F S F S F S F S F SF SF SF SF SF SF SF SF SF S F S F S F S F S F S F S F SF SILT FENCE LIMITS OF GRADING SILT FENCE LIMITS OF GRADING PROPERTY LINE IP IP IP IP IP IP IP IP IP IP SEDIMENT TRAP SCOURSTOP (TYP.) CE No.: 11 / 1 8 / 2 0 2 5 8 : 3 9 : 2 2 A M Pl o t T i m e S t a m p : DRAFT PREPARED FOR PRELIMINARY SUBMISSION AND REVIEW ONLY -- NOT FOR CONSTRUCTION. \\ c e - c o - s r v - 0 0 4 \ 3 0 0 - 3 9 9 \ 3 2 6 - 0 3 4 - 2 4 F o C o S o u t h e a s t C o m m u n i t y C e n t e r \ 0 3 ) A u t o C A D \ 3 2 6 0 3 4 - C 3 . 1 0 - E r o s i o n C o n t r o l . d w g Fi l e L o c a t i o n / N a m e : Architecture Engineering Planning Landscape Architecture Commissioning clarkenersen.com Kansas City, Missouri Lincoln, Nebraska Lawrence, Kansas Portland, Oregon Fort Collins, Colorado Omaha, Nebraska Charleston, South Carolina PDP/FDP Submittal - Round 1 Southeast Community Center Rock Creek Dr & Ziegler Rd Fort Collins, CO 80528 326-034-24 11/19/2025 Interim Erosion Control Plan C3.11SCALE: 1" = 50' INTERIM EROSION CONTROL PLAN 0'25'50'100' PROPOSED CONTOUR EXISTING CONTOUR APPROXIMATE LIMITS OF GRADING LEGEND EROSION CONTROL - SILT FENCE SF SF FLOWLINE IP EROSION CONROL - INLET PROTECTION INLET PROTECTION MH MH MH MH MH MH MH MH MH MH FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S UGE UGE UGE UGE UGE UGE UGE UGEUGEUGE UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UGE UGE UG E UG E UGE UGE UG E UG E UG E UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE D D S S OH E OH E OH E OH E OH E OH E OH E OH E OH E OH E OH E SSSSSS SS SS SS SS SS SS SS SS SS SS SS SS SS STOP MB D D UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UGE UGE ZI E G L E R R O A D ROCK CREEK DRIVE 4921 4921 49 1 5 49 1 8 4916 4920 4922 49 2 1 49 2 0 49 1 6 4915 4917 4919 4916 4918 49 1 4 49124914 4916 4914 4917 49 1 9 492 0 49 1 8 4919 4920 4921 49 2 2 49 2 3 49 2 4 49 1 9 4919 4920 4921 4918 4919 492 0 4921 49 1 5 4916 4917 49 1 8 491 9 49 2 0 49 2 1 491 6 49 1 7 49 1 8 49 1 9 49 2 0 49 2 1 49 2 2 49 1 4 49 1 4 49 1 5 49 1 5 49 1 6 49 1 6 491 7 49 1 7 49 1 8 49 1 8 491 8 491 9 49 2 0 49 2 1 PROPERTY LINE PROPERTY LINE PROPERTY LINE PROPERTY LINE SCOURSTOP (TYP.) CE No.: 11 / 1 8 / 2 0 2 5 8 : 3 9 : 2 5 A M Pl o t T i m e S t a m p : DRAFT PREPARED FOR PRELIMINARY SUBMISSION AND REVIEW ONLY -- NOT FOR CONSTRUCTION. \\ c e - c o - s r v - 0 0 4 \ 3 0 0 - 3 9 9 \ 3 2 6 - 0 3 4 - 2 4 F o C o S o u t h e a s t C o m m u n i t y C e n t e r \ 0 3 ) A u t o C A D \ 3 2 6 0 3 4 - C 3 . 1 0 - E r o s i o n C o n t r o l . d w g Fi l e L o c a t i o n / N a m e : Architecture Engineering Planning Landscape Architecture Commissioning clarkenersen.com Kansas City, Missouri Lincoln, Nebraska Lawrence, Kansas Portland, Oregon Fort Collins, Colorado Omaha, Nebraska Charleston, South Carolina PDP/FDP Submittal - Round 1 Southeast Community Center Rock Creek Dr & Ziegler Rd Fort Collins, CO 80528 326-034-24 11/19/2025 Final Erosion Control Plan C3.12SCALE: 1" = 50' FINAL EROSION CONTROL PLAN 0'25'50'100' PROPOSED CONTOUR EXISTING CONTOUR APPROXIMATE LIMITS OF GRADING LEGEND FLOWLINE SCOURSTOP 15 APPENDIX B. Drainage Plans I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R IRR IRR IRR IRR IRR IRR IRR I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R IR R IR R I R R FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S UGE UGE UGE UGE UGE UGE UGE UGEUGEUGE UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UGE UGE UG E UG E UGE UGE UG E UG E UG E UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE D D S S OH E OH E OH E OH E OH E OH E OH E OH E OH E OH E OH E SSSSSS SS SS SS SS SS SS SS SS SS SS SS SS SS STOP MB D D IRR IRR I R R I R R I R R IR R IRR UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UGE UGE ZI E G L E R R O A D ROCK CREEK DRIVE E1 6.50 0.31 E2 3.34 0.31 E3 0.44 0.31 E4 6.50 0.31 4919 4920 4921 49 2 2 49 2 3 49 2 4 49 1 9 4919 4920 4921 4918 4919 492 0 4921 49 1 5 4916 4917 49 1 8 491 9 49 2 0 49 2 1 491 6 49 1 7 49 1 8 49 1 9 49 2 0 49 2 1 49 2 2 49 1 4 49 1 4 49 1 5 49 1 5 49 1 6 49 1 6 491 7 49 1 7 49 1 8 49 1 8 491 8 491 9 49 2 0 49 2 1 PROPERTY LINE PROPERTY LINE PROPERTY LINE PROPERTY LINE CE No.: 11 / 1 7 / 2 0 2 5 2 : 0 3 : 4 6 P M Pl o t T i m e S t a m p : DRAFT PREPARED FOR PRELIMINARY SUBMISSION AND REVIEW ONLY -- NOT FOR CONSTRUCTION. \\ c e - c o - s r v - 0 0 4 \ 3 0 0 - 3 9 9 \ 3 2 6 - 0 3 4 - 2 4 F o C o S o u t h e a s t C o m m u n i t y C e n t e r \ 0 3 ) A u t o C A D \ 3 2 6 0 3 4 - C 3 . 0 8 - D r a i n a g e B a s i n s . d w g Fi l e L o c a t i o n / N a m e : Architecture Engineering Planning Landscape Architecture Commissioning clarkenersen.com Kansas City, Missouri Lincoln, Nebraska Lawrence, Kansas Portland, Oregon Fort Collins, Colorado Omaha, Nebraska Charleston, South Carolina PDP/FDP Submittal - Round 1 Southeast Community Center Rock Creek Dr & Ziegler Rd Fort Collins, CO 80528 326-034-24 11/19/2025 Existing Conditions Drainage Plan C3.08 PROPOSED CONTOUR EXISTING CONTOUR LEGEND FLOWLINE 1 0.50 0.80 BASIN NUMBER C100 BASIN AREA MH DRAIN BASIN LIMITS PROPOSED STORM INLET PROPOSED STORM LINE PROPOSED STORM MANHOLE EXISTING STORM MANHOLE SCALE: 1" = 50' EXISTING CONDITIONS DRAINAGE PLAN 0'25'50'100' MH MH MH MH MH MH MH MH MH I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R IRR IRR IRR IRR IRR IRR IRR I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R I R R IR R IR R I R R FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S S UGE UGE UGE UGE UGE UGE UGE UGEUGEUGE UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UGE UGE UG E UG E UGE UGE UG E UG E UG E UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE UGE D D S S OH E OH E OH E OH E OH E OH E OH E OH E OH E OH E OH E SSSSSS SS SS SS SS SS SS SS SS SS SS SS SS SS STOP MB D D IRR IRR I R R I R R I R R IR R IRR UG E UG E UG E UG E UG E UG E UG E UG E UG E UG E UGE UGE ZI E G L E R R O A D ROCK CREEK DRIVE P 3 P 5 P 5 P 4 P 6 P 12 P 11 P 7 P 10 P 2 P 13 P 15 P 14 P 16 P 1 4921 4921 49 1 5 49 1 8 4916 49 1 6 4920 4922 49 2 1 49 2 0 49 1 6 4915 4917 4919 4916 4918 49 1 7 49 1 449124914 4916 4914 4917 49 1 9 492 0 49 1 8 4919 4920 4921 49 2 2 49 2 3 49 2 4 49 1 9 4919 4920 4921 4918 4919 492 0 4921 49 1 5 4916 4917 49 1 8 491 9 49 2 0 49 2 1 491 6 49 1 7 49 1 8 49 1 9 49 2 0 49 2 1 49 2 2 49 1 4 49 1 4 49 1 5 49 1 5 49 1 6 49 1 6 491 7 49 1 7 49 1 8 49 1 8 491 8 491 9 49 2 0 49 2 1 PROPERTY LINE PROPERTY LINE PROPERTY LINE PROPERTY LINE P1 0.13 0.37 P5 0.69 1.00 P8 0.41 1.00 P6 0.76 0.87 P13 0.54 0.84 P14 1.19 1.00 P15 0.64 1.00 P9 0.13 1.00 P11 0.56 1.00 P12 0.47 1.00 P4 0.70 0.36 P18 0.16 0.32 P10 0.11 0.31 P16 1.78 0.33 P17 0.13 1.00 P2 0.59 0.56 P3 0.23 0.40 P7 0.27 0.90 P19 0.56 0.51 P 8 CE No.: 11 / 1 7 / 2 0 2 5 2 : 0 3 : 0 7 P M Pl o t T i m e S t a m p : DRAFT PREPARED FOR PRELIMINARY SUBMISSION AND REVIEW ONLY -- NOT FOR CONSTRUCTION. \\ c e - c o - s r v - 0 0 4 \ 3 0 0 - 3 9 9 \ 3 2 6 - 0 3 4 - 2 4 F o C o S o u t h e a s t C o m m u n i t y C e n t e r \ 0 3 ) A u t o C A D \ 3 2 6 0 3 4 - C 3 . 0 8 - D r a i n a g e B a s i n s . d w g Fi l e L o c a t i o n / N a m e : Architecture Engineering Planning Landscape Architecture Commissioning clarkenersen.com Kansas City, Missouri Lincoln, Nebraska Lawrence, Kansas Portland, Oregon Fort Collins, Colorado Omaha, Nebraska Charleston, South Carolina PDP/FDP Submittal - Round 1 Southeast Community Center Rock Creek Dr & Ziegler Rd Fort Collins, CO 80528 326-034-24 11/19/2025 Proposed Conditions Drainage Plan C3.09 PROPOSED CONTOUR EXISTING CONTOUR LEGEND FLOWLINE 1 0.50 0.80 BASIN NUMBER C100 BASIN AREA MH DRAIN BASIN LIMITS PROPOSED STORM INLET PROPOSED STORM LINE PROPOSED STORM MANHOLE EXISTING STORM MANHOLE SCALE: 1" = 50' PROPOSED CONDITIONS DRAINAGE PLAN 0'25'50'100' P 1 DESIGN POINT