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HomeMy WebLinkAboutPlans - Stormwater Management Plan - 01/29/2025STORMWATER MANAGEMENT PLAN Bloom Filing Six Fort Collins, CO Prepared for: MIC TDC Mulberry St Fort Collins LLC Dean Barber Dbarber@TDC-DEV.com Prepared by: 16911 Potts Place Mead, CO 80542 Phone: 970.217.9148 Project Number: 1061-3 January 29, 2025 Stormwater Management Plan Bloom Filing Six Located within the Southwest Quarter of Section 9, Township 7 North, Range 68 West of the 6th P.M. City of Fort Collins, County of Larimer, State of Colorado TABLE OF CONTENTS Page I. INTRODUCTION 2 A. Site Location B. Site Description C. Proposed Project Description D. Stormwater Quality Statement E. Stormwater Management Plan Objective F. Proposed Schedule II. SITE DESCRIPTION AND ACTIVITIES 4 A. Description of Construction Activities B. Expected Sequence for Major Activities C. Area Estimates D. Existing Vegetation E. Location and Description of Potential Pollution Sources/Discharges F. Receiving Waters III. BMPs FOR STORMWATER POLLUTION PREVENTION 7 A. Erosion and Sediment Controls B. Erosion Control Sequencing C. Materials Handling and Spill Prevention IV. ADDITIONAL CONTROLS 13 V. FINAL STABILIZATION AND LONG-TERM STORMWATER QUALITY 14 VI. INSPECTION AND MAINTENANCE PROCEDURES 14 VII. REFERENCES 16 VIII. APPENDICES 17 Stormwater Management Plan Bloom Filing Six, Fort Collins, CO 2 I. INTRODUCTION A. Site Location: The proposed development is located in the southwest quarter of Section 9, Township 7 North, Range 68 West, of the 6th Principal Meridian, City of Fort Collins, County of Larimer, State of Colorado. Furthermore, the project is north of Mulberry Street (and the Frontage Road) and east of Delozier Drive. The legal description of the property will be Bloom Filing Six. The subject site is currently vacant and has been overlot graded generally according to the Bloom Filing One construction improvements. B. Site Description: The subject area of this Stormwater Management Plan (SWMP) consists of roughly 96,620 s.f. (2.2 acres). The subject area generally contains the proposed Bloom Filing Six access road, detention pond and areas for grading. The proposed construction will consist of one phase and will be limited to detention pond grading, access road construction, curb/gutter, onsite sidewalk and landscaping. The Bloom Filing Six development will provide low impact development (LID) measures, water quality and detention for the improvements within Bloom Filing Six. The subject site is bound by Bloom Filing one to the north, Mulberry Street/Mulberry Street Frontage Road to the south and existing subdivisions on the west and east. The existing frontage road and adjacent swale generally slope at +/-0.5% from west to east. There is a high point in the roadway and swale near the southeastern corner of Bloom Filing Six. The Frontage Road in this area is not crowned and runoff generally flows from south to north across the Frontage Road. Runoff from the Frontage Road and Colorado Department of Transportation (CDOT) right-of- way reaches the existing swale north of the Frontage Road and flows from west to east. Runoff will continue across the property to the east and reach the Lake Canal. The Lake Canal is not on the State of Colorado’s Section 303(d) list of impaired waters. According to the Natural Resources Conversation Service (NRCS) Web Soil Survey, the native soils in this area are Ascalon Sandy Loam, 0 to 3 percent slope (Map Unit Symbol #7), which is a Type B soil; Garrett Loam, 0 to 1 percent slopes (Map Unit Symbol #40), which is a Type B soil; and, Nunn Clay Loam, wet, 1 to 3 percent slopes (Map Unit Symbol #76), which is a Type C soil. Please refer to the NRCS soils information in the Appendix. Stormwater Management Plan Bloom Filing Six, Fort Collins, CO 3 Please refer to the NRCS soils information in the Appendix. Existing drainage facilities near or adjacent to the site include existing curb & gutter and storm drainage infrastructure south of the subject site. There is an existing irrigation ditch (Lake Canal) along the northern property line for Bloom Filing Six. The Lake Canal continues to the southeast and is located east of the Bloom Filing Six Frontage Road Improvements. C. Proposed Project Description: The subject area of this Stormwater Management Plan (SWMP) consists of roughly 96,620 s.f. (2.2 acres). The subject area generally contains the proposed Bloom Filing Six access road, detention pond and areas for grading. The proposed construction will consist of one phase and will be limited to detention pond grading, access road construction, curb/gutter, onsite sidewalk and landscaping. Roughly 0.4 acres off-site will be disturbed for Frontage Road Improvements which are included in a CDOT SWMP. D. Stormwater Quality Statement Stormwater quality best management practices (BMPs) shall be implemented to minimize soil erosion, sedimentation, increased pollutant loads and stormwater impacts resulting from land disturbing activity associated with construction of the subject site and also minimize pollution of the downstream receiving waters. E. Stormwater Management Plan Objective The objective of this Stormwater Management Plan (SWMP) for the Bloom Filing Six, is to identify the BMPs which, when implemented, will meet the requirements of the City of Fort Collins standards. The SWMP goal is to identify possible pollutant sources that may contribute pollutants to stormwater as well as identify BMPs that, when implemented, will reduce or eliminate any possible impacts to water quality. 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. The SWMP is a “living” document which should be modified and updated through the course of site construction. Pollutant sources should be continuously evaluated during construction. BMPs should be selected, monitored, documented, implemented and pollutant sources be re-evaluated (and the process continued) through the construction lifecycle. Stormwater Management Plan Bloom Filing Six, Fort Collins, CO 4 A current copy of the SWMP shall be kept onsite at all times. A person familiar with the SWMP and on-site construction activities and clean-up procedures should be designated as the Qualified Stormwater Manager (QSM) for the site. QSM for the Project TBD QSM for the Contractor TBD The QSM will be responsible for (but not limited to) inspections and inspection reports, personnel training, regulatory agency contact, SWMP implementation and revisions, field notebooks, and record keeping of employee activities, contacts, and notifications. The stormwater management plan shall be implemented and installed by the QSM. The QSM for the Project and QSM for the Contractor shall perform the stormwater management inspections and keep appropriate records and logs for the inspections. F. Proposed Schedule Below is a proposed project schedule for the subject development and associated activities. Mobilization 7 days Site Grading for Roadway and Drainage/Detention Improvements 14 days Utility Construction 14 days The total expected construction timeframe for the project is 35 days. Appropriate stormwater management activities shall be in place prior to the commencement of major on-site activities. II. SITE DESCRIPTION AND ACTIVITIES A. Description of Construction Activities Construction activities will include: · Installation of initial BMPs; · Site grading operations; · Utility installations; · Construction of drainage conveyances including necessary swales and grading; · Installation of BMPs within swales; · Final site surfacing; · Final surface stabilization and site clean-up/demobilization. Stormwater Management Plan Bloom Filing Six, Fort Collins, CO 5 B. Expected Sequence for Major Activities The expected sequence for major construction activities includes: · Installation of initial BMPs; · Overlot grading, existing drainage conveyances shall be maintained; · Installation of onsite utilities; · Final site grading; · Final surface stabilization, including paving and landscaping. C. Area Estimates The subject area of this Stormwater Management Plan (SWMP) consists of roughly 96,620 s.f. (2.2 acres). The subject area generally contains the proposed Bloom Filing Six access road, detention pond and areas for grading. The proposed construction will consist of one phase and will be limited to detention pond grading, access road construction, curb/gutter, onsite sidewalk and landscaping. No buildings will be constructed as part of this SWMP. Roughly 0.4 acres off-site will be disturbed for Frontage Road Improvements which are included in a CDOT SWMP. D. Existing Vegetation The existing onsite vegetation consists of existing landscaping such as native grass and weeds. The existing ground cover is slightly conducive to minor erosion during major storm events. The existing vegetation cover for landscape areas onsite is estimated to be roughly 70%, based on visual observation. E. Location and Description of Potential Pollution Sources/Discharges Potential pollution sources include the following: a) disturbed and stored soils; b) vehicle tracking of sediments, c) management of contaminated soils, d) loading and unloading operations, e) outdoor storage activities, f) vehicle and equipment maintenance and fueling, g) significant dust or particulate generating processes (saw cutting material, including dust), h) routine maintenance activities involving fertilizers and pesticides, i) on-site waste management, j) concrete truck/equipment washing, k) dedicated asphalt, concrete batch plants or masonry mixing stations and l) non-industrial waste sources (such as worker trash and portable toilets). A description for each item is provided below: a) Disturbed and Stored Soils: On-site soils will be disturbed by site work, but should not be contaminated by pollutants. Control measures could include, but Stormwater Management Plan Bloom Filing Six, Fort Collins, CO 6 not be limited to, earthen berms, silt fence or other perimeter controls around the soils. b) Vehicle Tracking of Sediments: This will be controlled by the vehicle tracking control as shown on the Sediment and Erosion Control Plan. c) Management of Contaminated Soil: Contaminated soil is not expected within the project area. Furthermore, soil will not be contaminated by the contractor during the project. Should soil be contaminated during construction, i) the contaminating activity should be halted immediately, ii) the appropriate personnel for the Owner or regulatory agencies shall be notified, and iii) the handling of the contaminated soil shall be in accordance with applicable State and/or Federal regulations. d) Loading and Unloading Operations: Management of the loading and unloading operations will control potential pollution for this item. Loading and unloading shall only occur in areas with perimeter controls such as an earthen berm, silt fence or other perimeter controls have been installed. Any pollution observed during loading and unloading will be resolved immediately and appropriate personnel notified. e) Outdoor Storage Activities: Erodible building materials and fertilizers are not applicable to this project. No chemicals should be stored onsite for the construction activities of this project. f) Vehicle and Equipment Maintenance and fueling: This project will be completed in a single phase of site construction. Construction equipment will be fueled on and off site and is expected to be limited to the vehicles associated with this type of construction. Control measures for maintenance and fueling include, but are not limited to, i) secondary containment and cover where appropriate, ii) drip pans and absorbents shall be provided under vehicles with leaks, and iii) oil and oil waste shall be disposed of in accordance with appropriate requirements. Spill kits shall be readily available and near the maintenance and fueling area. Fuel for construction vehicles shall be stored on another vehicle or in the staging area with secondary containment. g) Significant Dust or Particulate Generating Processes: Clearing, grubbing, onsite grading and final surface stabilization have the potential for dust generation. Control measures may include the use of water trucks, hand spraying and silt fence around the perimeter of the area. Also, the contractor will be saw cutting for utility installation. The silica mud slush that is a result of this operation shall be vacuumed and discharged in the concrete washout area. h) Routine Maintenance Activities involving Fertilizers and Pesticides: This item is not applicable to this project. i) On-Site Waste Management: Project waste piles and liquid wastes are not applicable to this project. Dumpsters will be provided on-site for material waste. j) Concrete Truck/Equipment Washing: A concrete washout area will be installed as shown on the Sediment & Erosion Control Plans. k) Dedicated Asphalt, Concrete Batch Plant or Masonry Mixing Station: No asphalt or concrete will be produced on-site. l) Non-Industrial Waste Sources: Portable toilets will be present on-site and shall be emptied once per week. Stormwater Management Plan Bloom Filing Six, Fort Collins, CO 7 Refer to the Sediment & Erosion Control Plan for the location of the proposed staging area. The staging/stockpile area may be moved during construction due to site conditions and to maintain separation from stormwater conveyances and as site conditions warrant. F. Receiving Waters Runoff for the subject area flows to the existing conveyances adjacent to the project and eventually to Lake Canal, north and east of the site. Runoff from this project generally flows from south to north. A small portion of the subject site will flow from north to south to CDOT right-of-way. The receiving water for the project is Timnath Reservoir, which is located southeast of the subject site, via the Lake Canal. III. BMPs FOR STORMWATER POLLUTION PREVENTION A. Erosion and Sediment Controls Once construction activity begins, BMPs intended to contain sediment and erosion onsite shall be installed, inspected, maintained and replaced as necessary. Such controls shall be functional before upslope land disturbance begins. At a minimum, the BMPs shown on the Sediment & Erosion Control Plans shall be installed. The BMPs shall be supplemented as determined by onsite conditions in order to control sediment, pollutant discharge and ensure public safety. The following temporary and permanent BMPs shall be installed and maintained to control onsite erosion and prevent sediment transport off-site during construction activities. Temporary BMPs • Temporary Seeding is the establishment of a temporary vegetative cover on a graded area that will be exposed for longer than 14 days. Temporary seeding can be used on areas requiring temporary protection that will eventually need permanent vegetation at the completion of the construction or it can be used for areas that will be re-disturbed after a period of inactivity. Refer to the next page for the City of Fort Collins Seeding Mix. Stormwater Management Plan Bloom Filing Six, Fort Collins, CO 8 Seeding Mix Stormwater Management Plan Bloom Filing Six, Fort Collins, CO 9 • Vehicle Tracking Control (shown as VTC on the Sediment & Erosion Control Plan) is a stabilized stone pad located at points of ingress and egress on a construction site and acts as a temporary BMP. The stone pad is designed to reduce the amount of mud transported onto public roads by construction traffic by removing mud and sediment from the vehicle’s wheels when it drives over the gravel pad. These areas are limited to the minimum number necessary to provide functional construction access and installed prior to overlot grading activities. Whenever the construction entrance exists onto a public road, the road shall be cleaned at the end of each day. • Rock Sock (shown as RS on the Sediment & Erosion Control Plan) is a temporary BMP that is constructed of straw or small rocks that have been wrapped by wire mesh or geotextile to form an elongated cylindrical filter. Rock Socks are typically used either as concentrated velocity control or as part of inlet protection. Rock socks can be used along small, concentrated flow paths to control localized sediment loading and minimize scour caused by high velocities. • Sediment Control Log (shown as SCL on the Sediment & Erosion Control Plan) is a temporary BMP that is constructed of straw or small rocks that have been wrapped by geotextile to form an elongated cylindrical filter. Sediment Control Logs are typically used either as concentrated velocity control or as part of inlet protection. Sediment control logs can be used along small, concentrated flow paths to control localized sediment loading and minimize scour caused by high velocities. • Concrete Washout Area (shown as CWA on the Sediment & Erosion Control Plan) is a designated area designed to receive wash water from washing of tools and concrete mixer chutes, liquid concrete waste from dump trucks, mobile batch mixers, or pump trucks that acts as a temporary BMP. Concrete washout areas must be designated on all sites that will generate concrete wash water or liquid concrete waste from onsite concrete mixing or concrete delivery. Concrete washout activities must be conducted in a manner that does not contribute pollutants to surface waters or stormwater runoff. Concrete washout areas may be lined or unlined excavated pits in the ground, commercially manufactured prefabricated washout containers, or aboveground holding areas constructed of berms, sandbags, or straw bales with a plastic liner. • Silt Fence (shown as SF on the Sediment & Erosion Control Plan) is a temporary BMP that is typically used as filter structures in areas of sheet water flow such as landscape slopes. A silt fence is a geotextile fabric attached to wooden posts and trenched into the ground. A silt fence can be used where runoff is conveyed from a disturbed area as sheet flow. Silt fence is not designed to receive concentrated flow or to be used as a filter fabric. Typical uses include: down slope of a disturbed area to accept sheet flow, along the perimeter of a receiving water such as a stream, pond or wetland, and at the perimeter of a construction site. Stormwater Management Plan Bloom Filing Six, Fort Collins, CO 10 • Wind Borne Sediment and Dust Control measures shall be provided during the construction process to control wind borne sediment. During grading activities, water shall be applied to the disturbed soils for the purpose of maintaining cohesion with clay type soils and also to meet moisture requirements for compaction of disturbed soils. Other measures of mitigation for wind erosion may include the timely installation of seed and mulch following the establishment of final grade, and the timely installation of pavement following completion of utility trenching operations and curb construction. Permanent BMPs • Permanent Seeding and Mulching is the establishment of a permanent perennial vegetation such as trees, shrubs, vines, grasses/sod, or legumes on exposed areas for final permanent stabilization in order to provide stabilization of the soil by holding soil particles in place. It also reduces stormwater runoff velocity, maintains sheet flow, protects the soil surface from erosion, promotes infiltration of runoff, and improves wildlife habitat. The landscape plans for the site show the permanent seeding and plantings. The landscape areas are shown as LS on the Sediment & Erosion Control Plan. Refer to the City of Fort Collins Native Upland Seed Mix shown above for proposed seed mix. • Preservation of existing vegetation should occur where no construction activity is expected to occur. Preservation of natural vegetation is generally a permanent BMP and is applicable to construction sites with pre-existing vegetation. B. Erosion Control Sequencing The following is the proposed erosion control sequencing: Prior to Construction Preserve Existing Vegetation – Before construction commencement, areas that are not disturbed by construction activity should be preserved as needed with construction fencing, silt fencing, or other means to keep vehicular traffic out of the area to be left undisturbed. Silt Fence – Before earth disturbing activities, silt fence shall be placed downstream of areas where runoff from construction activities are expected to occur. In particular for this site, silt fence shall be placed downstream of the proposed stockpile area (if applicable). Vehicle Tracking Control – Before construction commencement but after a portion of asphalt demolition, vehicle tracking control shall be placed at points of ingress and egress. Stormwater Management Plan Bloom Filing Six, Fort Collins, CO 11 Vehicle Tracking Control should also be placed at the stockpile area exits (if applicable). During Construction Wind Borne Sediment and Dust Control – Wind borne sediment and dust control measures should be implemented during grading activities. Temporary Seeding – The landscaped areas shall be permanently seeded/planted at the end of construction. However, if the roadways/concrete apron do not have base course placed on them or the construction site is left disturbed without permanent stabilization 14 days after grading, temporary seeding shall be required. Permanent Seeding – Permanent seeding or landscaping shall be placed immediately in areas that are final graded and where little future disturbance is expected. In particular, permanent seeding should be included in the landscaped areas, and other areas that are not to be disturbed as part of construction. Post Construction Please refer to Final Stabilization and Long-term Stormwater Quality described below. C. Materials Handling and Spill Prevention The site development shall include the appropriate construction staging areas. Stormwater runoff generated from the staging areas shall be routed to a temporary sedimentation area where runoff shall be contained and filtered before being discharged off site. Reference the approved Sediment & Erosion Control Plan for the location of the staging area. The staging/stockpile area(s) may be moved to a location no closer than 100’ from a stormwater conveyance. Vehicle tracking control should be placed at the stockpile area entrance/exit and silt fence should surround it. If the stockpile/staging area(s) is moved, the SWMP should be updated. An effort by the Contractor shall be made to store only enough material required to complete the project. It is expected that only small pick-ups with diesel will be used for onsite refueling of vehicles. Any spill will be cleaned appropriately and according to the State of Colorado regulations. No other fueling operations are expected to be performed onsite. No truck or equipment washing will be conducted onsite. Vehicle cleaning will be performed off-site. An onsite portable toilet will be located prior to the beginning of construction. Also, an onsite dumpster for trash generated from the project will be located near the onsite staging area. Stormwater Management Plan Bloom Filing Six, Fort Collins, CO 12 Chemicals, fuels, lubricants, and paints typical with utility construction stored on-site shall be in water-tight containers and covered as necessary and stored in a bermed area, a storage building, or within a vehicle to act as secondary containment. Storage of onsite materials including fertilizers, waterline, sanitary sewer, and storm sewer shall be covered and placed on pallets to prevent direct contact with the ground and potential surface runoff. CDPHE requires that any hazardous material spill be reported when any of the following conditions occur: · Over 25 gallons of petroleum is spilled; · 5 CCs of Mercury are spilled; · Any and all raw sewage release; · Any or all State waters are impacted. If any of the above criteria is met or exceeded, the Colorado Department of Public Health and Environment, Local Emergency Planning committee, downstream users and other agencies (MS4s) shall be notified. The CDPHE shall be notified by telephone within 24 hours or the occurrence. In addition, written notification describing the spill and the clean up procedures used shall be sent to the agencies no later than five (5) days following the spill. If a spill does not meet the above criteria, reporting is not mandatory. WQCD Toll Free 24-hour Environmental Emergency Spill Reporting Line: 1-877-518-5608 When any spill occurs: · Notify the Qualified Stormwater Manager (QSM) and controlling operator of the site immediately following a hazardous spill. · The QSM shall be the 24-hour contact for the project. · Documentation of the spill should occur and the appropriate clean-up procedures. · At a minimum the following should be documented:  Nature of spill;  Quantity of spill;  Date/time spill occurred;  Agency notification if necessary;  Clean-up procedures used;  Daily monitoring (7 days) after clean-up;  Photographs of the incident area and subsequent clean-up;  Interview(s) with any witnesses of the event. General guidelines for clean-up procedures: · Immediately control or stop the release or spill;  Mitigate the spill as necessary with a spill prevention kit;  Obtain approved secondary containers to store any absorbents that are used; Stormwater Management Plan Bloom Filing Six, Fort Collins, CO 13  The spill shall be reported to the QSM and Responsible Person on the construction site for determination if further action or reporting is required or if emergency action or notification is appropriate. General Spill Control Practices: In addition to the good housekeeping and material management practice, the following practices shall be followed for spill prevention and cleanup: · Equipment and materials necessary for spill cleanup may include but are not be limited to: brooms, dust pans, mops, rags, gloves, goggles, absorbent powder/cat litter, sand, sawdust, and plastic and metal trash containers specifically for this purpose. The location of spill cleanup materials and equipment shall be identified on the site map and updated if necessary during construction. · The operator will inform the jobsite personnel that if a spill of any size occurs they are to always notify the QSM and, depending on the nature and severity of the spill, the QSM will contact the CDPHE, downstream users and other regulatory agencies. Hazardous waste disposal (that is not typical to this type of construction) is not included within this SWMP. OSHA standards shall be followed. Concrete and asphalt batch plants are not anticipated on this site and thus are not included in this SWMP. In the event of a spill or accident, it shall be contained and disposed of so that it will not flow from the site or soak into the soil. Once construction is completed, concrete waste and contaminated soil shall be disposed of properly. The QSM should be notified of all spills and appropriate action taken. IV. ADDITIONAL CONTROLS Solid waste materials, including disposable materials incidental to the major construction activities, shall be collected in containers. The containers shall be emptied periodically and hauled away from the site. Water used to establish and maintain grass, for dust control, and for other purposes during the construction phase must originate from a public water supply or private well approved by the CDPHE unless otherwise approved. Sanitary facilities shall be provided at the site throughout construction activities. They shall be utilized by construction personnel and serviced regularly by a commercial operator. Loading and Unloading Operations: Steps should be taken to minimize the movement of soil from the site. Contractors and laborers shall park along the street near the site as opposed to on the lot itself to prevent unwanted tracking of soil from the site. When loading/unloading equipment from vehicles, load/unload at the driveway or along the street near the site, to minimize the movement of soil from the site. Stormwater Management Plan Bloom Filing Six, Fort Collins, CO 14 Construction Employee Parking: To the extent practical, construction employee parking will be off-site or away from the construction area. V. FINAL STABILIZATION AND LONG-TERM STORMWATER QUALITY Final stabilization is reached when all soil disturbing activities at the site have been completed and vegetative cover has been established with a density of at least 70 percent of pre-disturbance levels or when equivalent permanent erosion reduction methods have been utilized. Final stabilization shall be performed in accordance with City of Fort Collins standards and the project documents. Upon final stabilization, temporary BMPs may be removed. Final, permanent stabilization will be achieved through implementing the site improvements on the approved construction drawings as well as the approved landscape plan for the proposed development. Permanent water quality for Bloom Filing Six will be provided through the proposed LID, water quality and detention pond. The detention pond release will be through the proposed structure and into Lake Canal. The Bloom Filing Six improvements will be released to the proposed detention pond and detained/treated runoff will reach the Lake Canal. Runoff that flows south will drain in the existing roadside swale and eventually reach the Lake Canal. VI. INSPECTION AND MAINTENANCE PROCEDURES The temporary BMP’s shall be inspected and documented at a minimum of once every 14 days and within 24 hours after each precipitation or snowmelt event. The SWMP shall be kept up-to-date with inspection records, maintenance procedures, and changes. Records should include complete inspection reports for each inspection, maintenance and repair reports as a result of the inspections, and records of maintenance as indicated in the State of Colorado standards, City of Fort Collins standards, manufacturer’s specifications, or other acceptable sources. A record-keeping system is recommended in managing inspection and maintenance reports and should include all maintenance records, spill response, weather conditions, training, correspondence, etc. Preventative maintenance also involves the regular inspection and testing of equipment, timely maintenance of the equipment, and complete records of the maintenance and inspections of the equipment. The maintenance and inspection records should be kept on site and made available upon request. Inspections must include the observation of the construction site perimeter, runoff discharge points, disturbed areas, staging areas (including concrete washout areas and fueling areas), erosion and sediment control measures identified in Stormwater Management Plan Bloom Filing Six, Fort Collins, CO 15 this SWMP, and any other structural BMP’s that may require maintenance. The inspection must determine if there is evidence of or potential for pollutants to enter the drainage system and if they should be modified, replaced, or amended. The following are possible maintenance procedures: • Upon inspection, erosion and sediment control measures determined to be in need of repair shall be maintained as soon as possible on items or areas identified in the inspection report. Most repairs shall be completed immediately. • Locations where vehicles enter or exit the site shall be inspected for evidence of sediment being tracked off-site by construction traffic. Such sediment shall be removed by the end of every working day. • Seeded areas shall be checked to see that grass coverage is maintained. Areas shall be watered, fertilized and reseeded as necessary. • It is the responsibility of the QSM to maintain effective pollutant discharge controls. Actual physical site conditions or contractor practices could make it necessary to install more control than are shown on the approved Sediment & Erosion Control Plan. For example, localized concentrations of surface runoff or unusually steep areas could require additional erosion control devices. Assessing the need for and implementing additional controls will be a continuing aspect of the SWMP until final stabilization. The intent of this Plan is to control water-borne and liquid pollutant discharges by some combination of interception, filtration, and containment. Parties implementing this plan must remain alert to the need to periodically refine and update the plan in order to accomplish the intended goals. • The contractor shall immediately clean-up any construction materials inadvertently deposited on existing streets, sidewalks or other public rights-of-way and make sure streets and walkways are cleaned at the end of each working day. Stormwater Management Plan Bloom Filing Six, Fort Collins, CO 16 VII. REFERENCES 1. Urban Drainage and Flood Control District, Drainage Criteria Manual Volumes 1, Revised August 2018, Volume 2, Revised September 2017 and the Volume 3, dated November 2010 and Updated October 2019. 2. Colorado Discharge Permit System (CDPS) General Permit COR 400000, Stormwater Discharges Associated with Construction Activity, Revised January 2021, by Colorado Department of Public Health and Environment. Stormwater Management Plan Bloom Filing Six, Fort Collins, CO 17 VIII.APPENDICIES  Vicinity Map  FEMA Information  Existing Soil Information  Best Management Practices (BMP) Schedule  Construction Stormwater Site Inspection Report  Construction BMP Fact Sheets  Drainage Plan  Sediment & Erosion Control Plan  CDPHE Permit (Placeholder) Vicinity Map © 2023 Microsoft Corporation © 2023 TomTom TRACT II, BLOOM FILING ONE FORT COLLINS, CO VICINITY MAP JLB C: \ U s e r s \ t r o y \ D r o p b o x \ I 2 \ P r o j e c t s \ 1 0 6 1 - 3 B l o o m \ D W G \ S h e e t s \ B l o o m _ C V . d w g , 1 2 / 1 9 / 2 0 2 3 1 : 4 5 : 3 9 P M , D W G T o P D F . p c 3 FEMA Information National Flood Hazard Layer FIRMette 0 500 1,000 1,500 2,000250 Feet Ü SEE FIS REPORT FOR DETAILED LEGEND AND INDEX MAP FOR FIRM PANEL LAYOUT SPECIAL FLOOD HAZARD AREAS Without Base Flood Elevation (BFE) Zone A, V, A99 With BFE or DepthZone AE, AO, AH, VE, AR Regulatory Floodway 0.2% Annual Chance Flood Hazard, Areas of 1% annual chance flood with average depth less than one foot or with drainage areas of less than one square mileZone X Future Conditions 1% Annual Chance Flood HazardZone X Area with Reduced Flood Risk due to Levee. See Notes.Zone X Area with Flood Risk due to LeveeZone D NO SCREEN Area of Minimal Flood Hazard Zone X Area of Undetermined Flood HazardZone D Channel, Culvert, or Storm Sewer Levee, Dike, or Floodwall Cross Sections with 1% Annual Chance 17.5 Water Surface Elevation Coastal Transect Coastal Transect Baseline Profile Baseline Hydrographic Feature Base Flood Elevation Line (BFE) Effective LOMRs Limit of Study Jurisdiction Boundary Digital Data Available No Digital Data Available Unmapped This map complies with FEMA's standards for the use of digital flood maps if it is not void as described below. The basemap shown complies with FEMA's basemap accuracy standards The flood hazard information is derived directly from the authoritative NFHL web services provided by FEMA. This map was exported on 12/13/2023 at 9:33 PM and does not reflect changes or amendments subsequent to this date and time. The NFHL and effective information may change or become superseded by new data over time. This map image is void if the one or more of the following map elements do not appear: basemap imagery, flood zone labels, legend, scale bar, map creation date, community identifiers, FIRM panel number, and FIRM effective date. Map images for unmapped and unmodernized areas cannot be used for regulatory purposes. Legend OTHER AREAS OF FLOOD HAZARD OTHER AREAS GENERAL STRUCTURES OTHER FEATURES MAP PANELS 8 B 20.2 The pin displayed on the map is an approximate point selected by the user and does not represent an authoritative property location. 1:6,000 105°1'28"W 40°35'10"N 105°0'51"W 40°34'43"N Basemap Imagery Source: USGS National Map 2023 B-1 Existing Soil Information Soil Map—Larimer County Area, Colorado (Tract II, Bloom Filing One) Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 12/13/2023 Page 1 of 3 44 9 2 2 7 0 44 9 2 3 1 0 44 9 2 3 5 0 44 9 2 3 9 0 44 9 2 4 3 0 44 9 2 4 7 0 44 9 2 5 1 0 44 9 2 5 5 0 44 9 2 5 9 0 44 9 2 2 7 0 44 9 2 3 1 0 44 9 2 3 5 0 44 9 2 3 9 0 44 9 2 4 3 0 44 9 2 4 7 0 44 9 2 5 1 0 44 9 2 5 5 0 44 9 2 5 9 0 498250 498290 498330 498370 498410 498450 498490 498250 498290 498330 498370 498410 498450 498490 40° 35' 2'' N 10 5 ° 1 ' 1 4 ' ' W 40° 35' 2'' N 10 5 ° 1 ' 4 ' ' W 40° 34' 52'' N 10 5 ° 1 ' 1 4 ' ' W 40° 34' 52'' N 10 5 ° 1 ' 4 ' ' W N Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 13N WGS84 0 50 100 200 300 Feet 0 20 40 80 120 Meters Map Scale: 1:1,570 if printed on A portrait (8.5" x 11") sheet. Soil Map may not be valid at this scale. B-2 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 18, Aug 24, 2023 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Jul 2, 2021—Aug 25, 2021 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. Soil Map—Larimer County Area, Colorado (Tract II, Bloom Filing One) Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 12/13/2023 Page 2 of 3 B-3 Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI 7 Ascalon sandy loam, 0 to 3 percent slopes 3.6 51.3% 40 Garrett loam, 0 to 1 percent slopes 3.1 44.8% 76 Nunn clay loam, wet, 1 to 3 percent slopes 0.3 3.9% Totals for Area of Interest 7.0 100.0% Soil Map—Larimer County Area, Colorado Tract II, Bloom Filing One Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 12/13/2023 Page 3 of 3 B-4 Hydrologic Soil Group—Larimer County Area, Colorado (Tract II, Bloom Filing One) Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 12/13/2023 Page 1 of 4 44 9 2 2 7 0 44 9 2 3 1 0 44 9 2 3 5 0 44 9 2 3 9 0 44 9 2 4 3 0 44 9 2 4 7 0 44 9 2 5 1 0 44 9 2 5 5 0 44 9 2 5 9 0 44 9 2 2 7 0 44 9 2 3 1 0 44 9 2 3 5 0 44 9 2 3 9 0 44 9 2 4 3 0 44 9 2 4 7 0 44 9 2 5 1 0 44 9 2 5 5 0 44 9 2 5 9 0 498250 498290 498330 498370 498410 498450 498490 498250 498290 498330 498370 498410 498450 498490 40° 35' 2'' N 10 5 ° 1 ' 1 4 ' ' W 40° 35' 2'' N 10 5 ° 1 ' 4 ' ' W 40° 34' 52'' N 10 5 ° 1 ' 1 4 ' ' W 40° 34' 52'' N 10 5 ° 1 ' 4 ' ' W N Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 13N WGS84 0 50 100 200 300 Feet 0 20 40 80 120 Meters Map Scale: 1:1,570 if printed on A portrait (8.5" x 11") sheet. Soil Map may not be valid at this scale. B-5 MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Rating Polygons A A/D B B/D C C/D D Not rated or not available Soil Rating Lines A A/D B B/D C C/D D Not rated or not available Soil Rating Points A A/D B B/D C C/D D Not rated or not available 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 18, Aug 24, 2023 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Jul 2, 2021—Aug 25, 2021 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. Hydrologic Soil Group—Larimer County Area, Colorado (Tract II, Bloom Filing One) Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 12/13/2023 Page 2 of 4 B-6 Hydrologic Soil Group Map unit symbol Map unit name Rating Acres in AOI Percent of AOI 7 Ascalon sandy loam, 0 to 3 percent slopes B 3.6 51.3% 40 Garrett loam, 0 to 1 percent slopes B 3.1 44.8% 76 Nunn clay loam, wet, 1 to 3 percent slopes C 0.3 3.9% Totals for Area of Interest 7.0 100.0% Description Hydrologic soil groups are based on estimates of runoff potential. Soils are assigned to one of four groups according to the rate of water infiltration when the soils are not protected by vegetation, are thoroughly wet, and receive precipitation from long-duration storms. The soils in the United States are assigned to four groups (A, B, C, and D) and three dual classes (A/D, B/D, and C/D). The groups are defined as follows: Group A. Soils having a high infiltration rate (low runoff potential) when thoroughly wet. These consist mainly of deep, well drained to excessively drained sands or gravelly sands. These soils have a high rate of water transmission. Group B. Soils having a moderate infiltration rate when thoroughly wet. These consist chiefly of moderately deep or deep, moderately well drained or well drained soils that have moderately fine texture to moderately coarse texture. These soils have a moderate rate of water transmission. Group C. Soils having a slow infiltration rate when thoroughly wet. These consist chiefly of soils having a layer that impedes the downward movement of water or soils of moderately fine texture or fine texture. These soils have a slow rate of water transmission. Group D. Soils having a very slow infiltration rate (high runoff potential) when thoroughly wet. These consist chiefly of clays that have a high shrink-swell potential, soils that have a high water table, soils that have a claypan or clay layer at or near the surface, and soils that are shallow over nearly impervious material. These soils have a very slow rate of water transmission. If a soil is assigned to a dual hydrologic group (A/D, B/D, or C/D), the first letter is for drained areas and the second is for undrained areas. Only the soils that in their natural condition are in group D are assigned to dual classes. Hydrologic Soil Group—Larimer County Area, Colorado Tract II, Bloom Filing One Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 12/13/2023 Page 3 of 4 B-7 Rating Options Aggregation Method: Dominant Condition Component Percent Cutoff: None Specified Tie-break Rule: Higher Hydrologic Soil Group—Larimer County Area, Colorado Tract II, Bloom Filing One Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 12/13/2023 Page 4 of 4 B-8 Best Management Practices (BMP) Schedule BMP Gantt ChartSediment & Erosion Control Detail Construction Phases Best Management Practice (BMP's)Mobilization Demolition Grading Utilitiy Installation Flat Work Installation Vertical Installation Landscape Demobilization Structural "Installation" Silt Fence Barriers* Contour Furrows (Ripping/Disking) Sediment Trap/Filter Vehicle Tracking Pad* Flow Barriers (Wattles)* Inlet Filter Bags*Any prior inlets that could use protecting. Rock Bags*Any prior inlets that could use protecting. Terracing Stream Flow Diversion* Rip Rap Collecting Asphalt/Concrete Saw Cutting Waste *All BMP's to be removed once construction is complete. Vegetative Temporary Seeding Planting Any time the site will sit dormant long14 than 30 days. Mulching/Sealant Any time the site will sit dormant longer than 30 days. Permanent Seeding Planting Sod Installation Rolled Products: Netting/Blankets/Mats Any time the site will sit dormant longer than 30 days. Other: Any time the site will sit dormant for longer than 14 days. Any time the site will sit dormant for longer than 14 days. Any time the site will sit dormant for longer than 14 days. Construction Stormwater Site Inspection Report CONSTRUCTION STORMWATER SITE INSPECTION REPORT Facility Name Permittee Date of Inspection Weather Conditions Permit Certification # Disturbed Acreage Phase of Construction Inspector Title Inspector Name Is the above inspector a qualified stormwater manager? (permittee is responsible for ensuring that the inspector is a qualified stormwater manager) INSPECTION FREQUENCY Check the box that describes the minimum inspection frequency utilized when conducting each inspection At least one inspection every 7 calendar days 24 hours after the end of any precipitation or snowmelt event that causes surface erosions • • • • If yes, describe below. INSPECTION REQUIREMENTS* *Use the attached Control Measures Requiring Routine Maintenance and Inadequate Control Measures Requiring Corrective Action forms to document results of this assessment that trigger either maintenance or corrective actions AREAS TO BE INSPECTED NO YES Document related maintenance, inadequate control measures and corrective actions Inadequate Control Measures Requiring Corrective Action form Other: ____________________ CONTROL MEASURES REQUIRING ROUTINE MAINTENANCE Definition: Any control measure that is still operating in accordance with its design and the requirements of the permit, but requires maintenance to prevent a breach of the control measure. These items are not subject to the corrective action requirements as specified in Part I.B.1.c of the permit. Are there control measures requiring maintenance? Date Observed Location Control Measure Maintenance Required INADEQUATE CONTROL MEASURES REQUIRING CORRECTIVE ACTION Definition: Any control measure that is not designed or implemented in accordance with the requirements of the permit and/or any control measure that is not implemented to operate in accordance with its design. This includes control measures that have not been implemented for pollutant sources. If it is infeasible to install or repair the control measure immediately after discovering the deficiency the reason must be documented and a schedule included to return the control measure to effective operating condition as possible. Are there inadequate control measures requiring corrective action? Are there additional control measures needed that were not in place at the time of inspection? Date Discovered Location Description of Inadequate Control Measure Description of Corrective Action discovered? YES/NO Date Corrected REPORTING REQUIREMENTS The permittee shall report the following circumstances orally within twenty-four (24) hours from the time the permittee becomes aware of the circumstances, and shall mail to the division a written report containing the information requested within five (5) working days after becoming aware of the following circumstances. The division may waive the written report required if the oral report has been received within 24 hours. All Noncompliance Requiring 24-Hour Notification per Part II.L.6 of the Permit a. Endangerment to Health or the Environment Circumstances leading to any noncompliance which may endanger health or the environment regardless of the cause of the incident (See Part II.L.6.a of the Permit) This category would primarily result from the discharge of pollutants in violation of the permit b. Numeric Effluent Limit Violations o Circumstances leading to any unanticipated bypass which exceeds any effluent limitations (See Part II.L.6.b of the Permit) o Circumstances leading to any upset which causes an exceedance of any effluent limitation (See Part II.L.6.c of the Permit) o Daily maximum violations (See Part II.L.6.d of the Permit) Numeric effluent limits are very uncommon in certifications under the COR400000 general permit. This category of noncompliance only applies if numeric effluent limits are included in a permit certification. Has there been an incident of noncompliance requiring 24-hour notification? Date and Time of Location Description of Noncompliance Description of Corrective Action 24 Hour Oral Date of 5 Day Written Notification * *Attach copy of 5 day written notification to report. Indicate if written notification was waived, including the name of the division personnel who granted waiver. After adequate corrective action(s) and maintenance have been taken, or where a report does not identify any incidents requiring corrective action or maintenance, the individual(s) designated as the Qualified Stormwater Manager, shall sign and certify the below statement: “I verify that, to the best of my knowledge and belief, all corrective action and maintenance items identified during the inspection are complete, and the site is currently in compliance with the permit.” ______________________________________ _______________________________________ Name of Qualified Stormwater Manager Title of Qualified Stormwater Manager ______________________________________ _______________________________________ Signature of Qualified Stormwater Manager Date Notes/Comments Construction BMP Fact Sheets Temporary and Permanent Seeding (TS/PS) EC-2 June 2012 Urban Drainage and Flood Control District TS/PS-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph TS/PS -1. Equipment used to drill seed. Photo courtesy of Douglas County. Description Temporary seeding can be used to stabilize disturbed areas that will be inactive for an extended period. Permanent seeding should be used to stabilize areas at final grade that will not be otherwise stabilized. Effective seeding includes preparation of a seedbed, selection of an appropriate seed mixture, proper planting techniques, and protection of the seeded area with mulch, geotextiles, or other appropriate measures. Appropriate Uses When the soil surface is disturbed and will remain inactive for an extended period (typically 30 days or longer), proactive stabilization measures should be implemented. If the inactive period is short-lived (on the order of two weeks), techniques such as surface roughening may be appropriate. For longer periods of inactivity, temporary seeding and mulching can provide effective erosion control. Permanent seeding should be used on finished areas that have not been otherwise stabilized. Typically, local governments have their own seed mixes and timelines for seeding. Check jurisdictional requirements for seeding and temporary stabilization. Design and Installation Effective seeding requires proper seedbed preparation, selection of an appropriate seed mixture, use of appropriate seeding equipment to ensure proper coverage and density, and protection with mulch or fabric until plants are established. The USDCM Volume 2 Revegetation Chapter contains detailed seed mix, soil preparations, and seeding and mulching recommendations that may be referenced to supplement this Fact Sheet. Drill seeding is the preferred seeding method. Hydroseeding is not recommended except in areas where steep slopes prevent use of drill seeding equipment, and even in these instances it is preferable to hand seed and mulch. Some jurisdictions do not allow hydroseeding or hydromulching. Seedbed Preparation Prior to seeding, ensure that areas to be revegetated have soil conditions capable of supporting vegetation. Overlot grading can result in loss of topsoil, resulting in poor quality subsoils at the ground surface that have low nutrient value, little organic matter content, few soil microorganisms, rooting restrictions, and conditions less conducive to infiltration of precipitation. As a result, it is typically necessary to provide stockpiled topsoil, compost, or other Temporary and Permanent Seeding Functions Erosion Control Yes Sediment Control No Site/Material Management No EC-2 Temporary and Permanent Seeding (TS/PS) TS/PS-2 Urban Drainage and Flood Control District June 2012 Urban Storm Drainage Criteria Manual Volume 3 soil amendments and rototill them into the soil to a depth of 6 inches or more. Topsoil should be salvaged during grading operations for use and spread on areas to be revegetated later. Topsoil should be viewed as an important resource to be utilized for vegetation establishment, due to its water-holding capacity, structure, texture, organic matter content, biological activity, and nutrient content. The rooting depth of most native grasses in the semi-arid Denver metropolitan area is 6 to 18 inches. At a minimum, the upper 6 inches of topsoil should be stripped, stockpiled, and ultimately respread across areas that will be revegetated. Where topsoil is not available, subsoils should be amended to provide an appropriate plant-growth medium. Organic matter, such as well digested compost, can be added to improve soil characteristics conducive to plant growth. Other treatments can be used to adjust soil pH conditions when needed. Soil testing, which is typically inexpensive, should be completed to determine and optimize the types and amounts of amendments that are required. If the disturbed ground surface is compacted, rip or rototill the surface prior to placing topsoil. If adding compost to the existing soil surface, rototilling is necessary. Surface roughening will assist in placement of a stable topsoil layer on steeper slopes, and allow infiltration and root penetration to greater depth. Prior to seeding, the soil surface should be rough and the seedbed should be firm, but neither too loose nor compacted. The upper layer of soil should be in a condition suitable for seeding at the proper depth and conducive to plant growth. Seed-to-soil contact is the key to good germination. Seed Mix for Temporary Vegetation To provide temporary vegetative cover on disturbed areas which will not be paved, built upon, or fully landscaped or worked for an extended period (typically 30 days or more), plant an annual grass appropriate for the time of planting and mulch the planted areas. Annual grasses suitable for the Denver metropolitan area are listed in Table TS/PS-1. These are to be considered only as general recommendations when specific design guidance for a particular site is not available. Local governments typically specify seed mixes appropriate for their jurisdiction. Seed Mix for Permanent Revegetation To provide vegetative cover on disturbed areas that have reached final grade, a perennial grass mix should be established. Permanent seeding should be performed promptly (typically within 14 days) after reaching final grade. Each site will have different characteristics and a landscape professional or the local jurisdiction should be contacted to determine the most suitable seed mix for a specific site. In lieu of a specific recommendation, one of the perennial grass mixes appropriate for site conditions and growth season listed in Table TS/PS-2 can be used. The pure live seed (PLS) rates of application recommended in these tables are considered to be absolute minimum rates for seed applied using proper drill-seeding equipment. If desired for wildlife habitat or landscape diversity, shrubs such as rubber rabbitbrush (Chrysothamnus nauseosus), fourwing saltbush (Atriplex canescens) and skunkbrush sumac (Rhus trilobata) could be added to the upland seedmixes at 0.25, 0.5 and 1 pound PLS/acre, respectively. In riparian zones, planting root stock of such species as American plum (Prunus americana), woods rose (Rosa woodsii), plains cottonwood (Populus sargentii), and willow (Populus spp.) may be considered. On non-topsoiled upland sites, a legume such as Ladak alfalfa at 1 pound PLS/acre can be included as a source of nitrogen for perennial grasses. Temporary and Permanent Seeding (TS/PS) EC-2 June 2012 Urban Drainage and Flood Control District TS/PS-3 Urban Storm Drainage Criteria Manual Volume 3 Seeding dates for the highest success probability of perennial species along the Front Range are generally in the spring from April through early May and in the fall after the first of September until the ground freezes. If the area is irrigated, seeding may occur in summer months, as well. See Table TS/PS-3 for appropriate seeding dates. Table TS/PS-1. Minimum Drill Seeding Rates for Various Temporary Annual Grasses Speciesa (Common name) Growth Seasonb Pounds of Pure Live Seed (PLS)/acrec Planting Depth (inches) 1. Oats Cool 35 - 50 1 - 2 2. Spring wheat Cool 25 - 35 1 - 2 3. Spring barley Cool 25 - 35 1 - 2 4. Annual ryegrass Cool 10 - 15 ½ 5. Millet Warm 3 - 15 ½ - ¾ 6. Sudangrass Warm 5–10 ½ - ¾ 7. Sorghum Warm 5–10 ½ - ¾ 8. Winter wheat Cool 20–35 1 - 2 9. Winter barley Cool 20–35 1 - 2 10. Winter rye Cool 20–35 1 - 2 11. Triticale Cool 25–40 1 - 2 a Successful seeding of annual grass resulting in adequate plant growth will usually produce enough dead-plant residue to provide protection from wind and water erosion for an additional year. This assumes that the cover is not disturbed or mowed closer than 8 inches. Hydraulic seeding may be substituted for drilling only where slopes are steeper than 3:1 or where access limitations exist. When hydraulic seeding is used, hydraulic mulching should be applied as a separate operation, when practical, to prevent the seeds from being encapsulated in the mulch. b See Table TS/PS-3 for seeding dates. Irrigation, if consistently applied, may extend the use of cool season species during the summer months. c Seeding rates should be doubled if seed is broadcast, or increased by 50 percent if done using a Brillion Drill or by hydraulic seeding. EC-2 Temporary and Permanent Seeding (TS/PS) TS/PS-4 Urban Drainage and Flood Control District June 2012 Urban Storm Drainage Criteria Manual Volume 3 Table TS/PS-2. Minimum Drill Seeding Rates for Perennial Grasses Commona Name Botanical Name Growth Seasonb Growth Form Seeds/ Pound Pounds of PLS/acre Alakali Soil Seed Mix Alkali sacaton Sporobolus airoides Cool Bunch 1,750,000 0.25 Basin wildrye Elymus cinereus Cool Bunch 165,000 2.5 Sodar streambank wheatgrass Agropyron riparium 'Sodar' Cool Sod 170,000 2.5 Jose tall wheatgrass Agropyron elongatum 'Jose' Cool Bunch 79,000 7.0 Arriba western wheatgrass Agropyron smithii 'Arriba' Cool Sod 110,000 5.5 Total 17.75 Fertile Loamy Soil Seed Mix Ephriam crested wheatgrass Agropyron cristatum 'Ephriam' Cool Sod 175,000 2.0 Dural hard fescue Festuca ovina 'duriuscula' Cool Bunch 565,000 1.0 Lincoln smooth brome Bromus inermis leyss 'Lincoln' Cool Sod 130,000 3.0 Sodar streambank wheatgrass Agropyron riparium 'Sodar' Cool Sod 170,000 2.5 Arriba western wheatgrass Agropyron smithii 'Arriba' Cool Sod 110,000 7.0 Total 15.5 High Water Table Soil Seed Mix Meadow foxtail Alopecurus pratensis Cool Sod 900,000 0.5 Redtop Agrostis alba Warm Open sod 5,000,000 0.25 Reed canarygrass Phalaris arundinacea Cool Sod 68,000 0.5 Lincoln smooth brome Bromus inermis leyss 'Lincoln' Cool Sod 130,000 3.0 Pathfinder switchgrass Panicum virgatum 'Pathfinder' Warm Sod 389,000 1.0 Alkar tall wheatgrass Agropyron elongatum 'Alkar' Cool Bunch 79,000 5.5 Total 10.75 Transition Turf Seed Mixc Ruebens Canadian bluegrass Poa compressa 'Ruebens' Cool Sod 2,500,000 0.5 Dural hard fescue Festuca ovina 'duriuscula' Cool Bunch 565,000 1.0 Citation perennial ryegrass Lolium perenne 'Citation' Cool Sod 247,000 3.0 Lincoln smooth brome Bromus inermis leyss 'Lincoln' Cool Sod 130,000 3.0 Total 7.5 Temporary and Permanent Seeding (TS/PS) EC-2 June 2012 Urban Drainage and Flood Control District TS/PS-5 Urban Storm Drainage Criteria Manual Volume 3 Table TS/PS-2. Minimum Drill Seeding Rates for Perennial Grasses (cont.) Common Name Botanical Name Growth Seasonb Growth Form Seeds/ Pound Pounds of PLS/acre Sandy Soil Seed Mix Blue grama Bouteloua gracilis Warm Sod-forming bunchgrass 825,000 0.5 Camper little bluestem Schizachyrium scoparium 'Camper' Warm Bunch 240,000 1.0 Prairie sandreed Calamovilfa longifolia Warm Open sod 274,000 1.0 Sand dropseed Sporobolus cryptandrus Cool Bunch 5,298,000 0.25 Vaughn sideoats grama Bouteloua curtipendula 'Vaughn' Warm Sod 191,000 2.0 Arriba western wheatgrass Agropyron smithii 'Arriba' Cool Sod 110,000 5.5 Total 10.25 Heavy Clay, Rocky Foothill Seed Mix Ephriam crested wheatgrassd Agropyron cristatum 'Ephriam' Cool Sod 175,000 1.5 Oahe Intermediate wheatgrass Agropyron intermedium 'Oahe' Cool Sod 115,000 5.5 Vaughn sideoats gramae Bouteloua curtipendula 'Vaughn' Warm Sod 191,000 2.0 Lincoln smooth brome Bromus inermis leyss 'Lincoln' Cool Sod 130,000 3.0 Arriba western wheatgrass Agropyron smithii 'Arriba' Cool Sod 110,000 5.5 Total 17.5 a All of the above seeding mixes and rates are based on drill seeding followed by crimped straw mulch. These rates should be doubled if seed is broadcast and should be increased by 50 percent if the seeding is done using a Brillion Drill or is applied through hydraulic seeding. Hydraulic seeding may be substituted for drilling only where slopes are steeper than 3:1. If hydraulic seeding is used, hydraulic mulching should be done as a separate operation. b See Table TS/PS-3 for seeding dates. c If site is to be irrigated, the transition turf seed rates should be doubled. d Crested wheatgrass should not be used on slopes steeper than 6H to 1V. e Can substitute 0.5 lbs PLS of blue grama for the 2.0 lbs PLS of Vaughn sideoats grama. EC-2 Temporary and Permanent Seeding (TS/PS) TS/PS-6 Urban Drainage and Flood Control District June 2012 Urban Storm Drainage Criteria Manual Volume 3 Table TS/PS-3. Seeding Dates for Annual and Perennial Grasses Annual Grasses (Numbers in table reference species in Table TS/PS-1) Perennial Grasses Seeding Dates Warm Cool Warm Cool January 1–March 15   March 16–April 30 4 1,2,3   May 1–May 15 4  May 16–June 30 4,5,6,7 July 1–July 15 5,6,7 July 16–August 31 September 1–September 30 8,9,10,11 October 1–December 31   Mulch Cover seeded areas with mulch or an appropriate rolled erosion control product to promote establishment of vegetation. Anchor mulch by crimping, netting or use of a non-toxic tackifier. See the Mulching BMP Fact Sheet for additional guidance. Maintenance and Removal Monitor and observe seeded areas to identify areas of poor growth or areas that fail to germinate. Reseed and mulch these areas, as needed. An area that has been permanently seeded should have a good stand of vegetation within one growing season if irrigated and within three growing seasons without irrigation in Colorado. Reseed portions of the site that fail to germinate or remain bare after the first growing season. Seeded areas may require irrigation, particularly during extended dry periods. Targeted weed control may also be necessary. Protect seeded areas from construction equipment and vehicle access. Good Housekeeping Practices (GH) MM-3 November 2010 Urban Drainage and Flood Control District GH-1 Urban Storm Drainage Criteria Manual Volume 3 Photographs GH-1 and GH-2. Proper materials storage and secondary containment for fuel tanks are important good housekeeping practices. Photos courtesy of CDOT and City of Aurora. Description Implement construction site good housekeeping practices to prevent pollution associated with solid, liquid and hazardous construction-related materials and wastes. Stormwater Management Plans (SWMPs) should clearly specify BMPs including these good housekeeping practices:  Provide for waste management.  Establish proper building material staging areas.  Designate paint and concrete washout areas.  Establish proper equipment/vehicle fueling and maintenance practices.  Control equipment/vehicle washing and allowable non- stormwater discharges.  Develop a spill prevention and response plan. Acknowledgement: This Fact Sheet is based directly on EPA guidance provided in Developing Your Stormwater Pollution Prevent Plan (EPA 2007). Appropriate Uses Good housekeeping practices are necessary at all construction sites. Design and Installation The following principles and actions should be addressed in SWMPs:  Provide for Waste Management. Implement management procedures and practices to prevent or reduce the exposure and transport of pollutants in stormwater from solid, liquid and sanitary wastes that will be generated at the site. Practices such as trash disposal, recycling, proper material handling, and cleanup measures can reduce the potential for stormwater runoff to pick up construction site wastes and discharge them to surface waters. Implement a comprehensive set of waste-management practices for hazardous or toxic materials, such as paints, solvents, petroleum products, pesticides, wood preservatives, acids, roofing tar, and other materials. Practices should include storage, handling, inventory, and cleanup procedures, in case of spills. Specific practices that should be considered include: Solid or Construction Waste o Designate trash and bulk waste-collection areas on- site. Good Housekeeping Functions Erosion Control No Sediment Control No Site/Material Management Yes MM-3 Good Housekeeping Practices (GH) GH-2 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Photograph GH-3. Locate portable toilet facilities on level surfaces away from waterways and storm drains. Photo courtesy of WWE. o Recycle materials whenever possible (e.g., paper, wood, concrete, oil). o Segregate and provide proper disposal options for hazardous material wastes. o Clean up litter and debris from the construction site daily. o Locate waste-collection areas away from streets, gutters, watercourses, and storm drains. Waste- collection areas (dumpsters, and such) are often best located near construction site entrances to minimize traffic on disturbed soils. Consider secondary containment around waste collection areas to minimize the likelihood of contaminated discharges. o Empty waste containers before they are full and overflowing. Sanitary and Septic Waste o Provide convenient, well-maintained, and properly located toilet facilities on-site. o Locate toilet facilities away from storm drain inlets and waterways to prevent accidental spills and contamination of stormwater. o Maintain clean restroom facilities and empty portable toilets regularly. o Where possible, provide secondary containment pans under portable toilets. o Provide tie-downs or stake-downs for portable toilets. o Educate employees, subcontractors, and suppliers on locations of facilities. o Treat or dispose of sanitary and septic waste in accordance with state or local regulations. Do not discharge or bury wastewater at the construction site. o Inspect facilities for leaks. If found, repair or replace immediately. o Special care is necessary during maintenance (pump out) to ensure that waste and/or biocide are not spilled on the ground. Hazardous Materials and Wastes o Develop and implement employee and subcontractor education, as needed, on hazardous and toxic waste handling, storage, disposal, and cleanup. o Designate hazardous waste-collection areas on-site. o Place all hazardous and toxic material wastes in secondary containment. Good Housekeeping Practices (GH) MM-3 November 2010 Urban Drainage and Flood Control District GH-3 Urban Storm Drainage Criteria Manual Volume 3 o Hazardous waste containers should be inspected to ensure that all containers are labeled properly and that no leaks are present.  Establish Proper Building Material Handling and Staging Areas. The SWMP should include comprehensive handling and management procedures for building materials, especially those that are hazardous or toxic. Paints, solvents, pesticides, fuels and oils, other hazardous materials or building materials that have the potential to contaminate stormwater should be stored indoors or under cover whenever possible or in areas with secondary containment. Secondary containment measures prevent a spill from spreading across the site and may include dikes, berms, curbing, or other containment methods. Secondary containment techniques should also ensure the protection of groundwater. Designate staging areas for activities such as fueling vehicles, mixing paints, plaster, mortar, and other potential pollutants. Designated staging areas enable easier monitoring of the use of materials and clean up of spills. Training employees and subcontractors is essential to the success of this pollution prevention principle. Consider the following specific materials handling and staging practices: o Train employees and subcontractors in proper handling and storage practices. o Clearly designate site areas for staging and storage with signs and on construction drawings. Staging areas should be located in areas central to the construction site. Segment the staging area into sub-areas designated for vehicles, equipment, or stockpiles. Construction entrances and exits should be clearly marked so that delivery vehicles enter/exit through stabilized areas with vehicle tracking controls (See Vehicle Tracking Control Fact Sheet). o Provide storage in accordance with Spill Protection, Control and Countermeasures (SPCC) requirements and plans and provide cover and impermeable perimeter control, as necessary, for hazardous materials and contaminated soils that must be stored on site. o Ensure that storage containers are regularly inspected for leaks, corrosion, support or foundation failure, or other signs of deterioration and tested for soundness. o Reuse and recycle construction materials when possible.  Designate Concrete Washout Areas. Concrete contractors should be encouraged to use the washout facilities at their own plants or dispatch facilities when feasible; however, concrete washout commonly occurs on construction sites. If it is necessary to provide for concrete washout areas on- site, designate specific washout areas and design facilities to handle anticipated washout water. Washout areas should also be provided for paint and stucco operations. Because washout areas can be a source of pollutants from leaks or spills, care must be taken with regard to their placement and proper use. See the Concrete Washout Area Fact Sheet for detailed guidance. Both self-constructed and prefabricated washout containers can fill up quickly when concrete, paint, and stucco work are occurring on large portions of the site. Be sure to check for evidence that contractors are using the washout areas and not dumping materials onto the ground or into drainage facilities. If the washout areas are not being used regularly, consider posting additional signage, relocating the facilities to more convenient locations, or providing training to workers and contractors. When concrete, paint, or stucco is part of the construction process, consider these practices which will help prevent contamination of stormwater. Include the locations of these areas and the maintenance and inspection procedures in the SWMP. MM-3 Good Housekeeping Practices (GH) GH-4 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 o Do not washout concrete trucks or equipment into storm drains, streets, gutters, uncontained areas, or streams. Only use designated washout areas. o Establish washout areas and advertise their locations with signs. Ensure that signage remains in good repair. o Provide adequate containment for the amount of wash water that will be used. o Inspect washout structures daily to detect leaks or tears and to identify when materials need to be removed. o Dispose of materials properly. The preferred method is to allow the water to evaporate and to recycle the hardened concrete. Full service companies may provide dewatering services and should dispose of wastewater properly. Concrete wash water can be highly polluted. It should not be discharged to any surface water, storm sewer system, or allowed to infiltrate into the ground in the vicinity of waterbodies. Washwater should not be discharged to a sanitary sewer system without first receiving written permission from the system operator.  Establish Proper Equipment/Vehicle Fueling and Maintenance Practices. Create a clearly designated on-site fueling and maintenance area that is clean and dry. The on-site fueling area should have a spill kit, and staff should know how to use it. If possible, conduct vehicle fueling and maintenance activities in a covered area. Consider the following practices to help prevent the discharge of pollutants to stormwater from equipment/vehicle fueling and maintenance. Include the locations of designated fueling and maintenance areas and inspection and maintenance procedures in the SWMP. o Train employees and subcontractors in proper fueling procedures (stay with vehicles during fueling, proper use of pumps, emergency shutoff valves, etc.). o Inspect on-site vehicles and equipment regularly for leaks, equipment damage, and other service problems. o Clearly designate vehicle/equipment service areas away from drainage facilities and watercourses to prevent stormwater run-on and runoff. o Use drip pans, drip cloths, or absorbent pads when replacing spent fluids. o Collect all spent fluids, store in appropriate labeled containers in the proper storage areas, and recycle fluids whenever possible.  Control Equipment/Vehicle Washing and Allowable Non-Stormwater Discharges. Implement practices to prevent contamination of surface and groundwater from equipment and vehicle wash water. Representative practices include: o Educate employees and subcontractors on proper washing procedures. o Use off-site washing facilities, when available. o Clearly mark the washing areas and inform workers that all washing must occur in this area. o Contain wash water and treat it using BMPs. Infiltrate washwater when possible, but maintain separation from drainage paths and waterbodies. Good Housekeeping Practices (GH) MM-3 November 2010 Urban Drainage and Flood Control District GH-5 Urban Storm Drainage Criteria Manual Volume 3 o Use high-pressure water spray at vehicle washing facilities without detergents. Water alone can remove most dirt adequately. o Do not conduct other activities, such as vehicle repairs, in the wash area. o Include the location of the washing facilities and the inspection and maintenance procedures in the SWMP.  Develop a Spill Prevention and Response Plan. Spill prevention and response procedures must be identified in the SWMP. Representative procedures include identifying ways to reduce the chance of spills, stop the source of spills, contain and clean up spills, dispose of materials contaminated by spills, and train personnel responsible for spill prevention and response. The plan should also specify material handling procedures and storage requirements and ensure that clear and concise spill cleanup procedures are provided and posted for areas in which spills may potentially occur. When developing a spill prevention plan, include the following: o Note the locations of chemical storage areas, storm drains, tributary drainage areas, surface waterbodies on or near the site, and measures to stop spills from leaving the site. o Provide proper handling and safety procedures for each type of waste. Keep Material Safety Data Sheets (MSDSs) for chemical used on site with the SWMP. o Establish an education program for employees and subcontractors on the potential hazards to humans and the environment from spills and leaks. o Specify how to notify appropriate authorities, such as police and fire departments, hospitals, or municipal sewage treatment facilities to request assistance. Emergency procedures and contact numbers should be provided in the SWMP and posted at storage locations. o Describe the procedures, equipment and materials for immediate cleanup of spills and proper disposal. o Identify personnel responsible for implementing the plan in the event of a spill. Update the spill prevention plan and clean up materials as changes occur to the types of chemicals stored and used at the facility. MM-3 Good Housekeeping Practices (GH) GH-6 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Spill Prevention, Control, and Countermeasure (SPCC) Plan Construction sites may be subject to 40 CFR Part 112 regulations that require the preparation and implementation of a SPCC Plan to prevent oil spills from aboveground and underground storage tanks. The facility is subject to this rule if it is a non-transportation-related facility that:  Has a total storage capacity greater than 1,320 gallons or a completely buried storage capacity greater than 42,000 gallons.  Could reasonably be expected to discharge oil in quantities that may be harmful to navigable waters of the United States and adjoining shorelines. Furthermore, if the facility is subject to 40 CFR Part 112, the SWMP should reference the SPCC Plan. To find out more about SPCC Plans, see EPA's website on SPPC at www.epa.gov/oilspill/spcc.htm. Reporting Oil Spills In the event of an oil spill, contact the National Response Center toll free at 1-800-424- 8802 for assistance, or for more details, visit their website: www.nrc.uscg.mil. Maintenance and Removal Effective implementation of good housekeeping practices is dependent on clear designation of personnel responsible for supervising and implementing good housekeeping programs, such as site cleanup and disposal of trash and debris, hazardous material management and disposal, vehicle and equipment maintenance, and other practices. Emergency response "drills" may aid in emergency preparedness. Checklists may be helpful in good housekeeping efforts. Staging and storage areas require permanent stabilization when the areas are no longer being used for construction-related activities. Construction-related materials, debris and waste must be removed from the construction site once construction is complete. Design Details See the following Fact Sheets for related Design Details: MM-1 Concrete Washout Area MM-2 Stockpile Management SM-4 Vehicle Tracking Control Design details are not necessary for other good housekeeping practices; however, be sure to designate where specific practices will occur on the appropriate construction drawings. Silt Fence (SF) SC-1 November 2010 Urban Drainage and Flood Control District SF-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph SF-1. Silt fence creates a sediment barrier, forcing sheet flow runoff to evaporate or infiltrate. Description A silt fence is a woven geotextile fabric attached to wooden posts and trenched into the ground. It is designed as a sediment barrier to intercept sheet flow runoff from disturbed areas. Appropriate Uses A silt fence can be used where runoff is conveyed from a disturbed area as sheet flow. Silt fence is not designed to receive concentrated flow or to be used as a filter fabric. Typical uses include:  Down slope of a disturbed area to accept sheet flow.  Along the perimeter of a receiving water such as a stream, pond or wetland.  At the perimeter of a construction site. Design and Installation Silt fence should be installed along the contour of slopes so that it intercepts sheet flow. The maximum recommended tributary drainage area per 100 lineal feet of silt fence, installed along the contour, is approximately 0.25 acres with a disturbed slope length of up to 150 feet and a tributary slope gradient no steeper than 3:1. Longer and steeper slopes require additional measures. This recommendation only applies to silt fence installed along the contour. Silt fence installed for other uses, such as perimeter control, should be installed in a way that will not produce concentrated flows. For example, a "J-hook" installation may be appropriate to force runoff to pond and evaporate or infiltrate in multiple areas rather than concentrate and cause erosive conditions parallel to the silt fence. See Detail SF-1 for proper silt fence installation, which involves proper trenching, staking, securing the fabric to the stakes, and backfilling the silt fence. Properly installed silt fence should not be easily pulled out by hand and there should be no gaps between the ground and the fabric. Silt fence must meet the minimum allowable strength requirements, depth of installation requirement, and other specifications in the design details. Improper installation of silt fence is a common reason for silt fence failure; however, when properly installed and used for the appropriate purposes, it can be highly effective. Silt Fence Functions Erosion Control No Sediment Control Yes Site/Material Management No SC-1 Silt Fence (SF) SF-2 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Photograph SF-2. When silt fence is not installed along the contour, a "J-hook" installation may be appropriate to ensure that the BMP does not create concentrated flow parallel to the silt fence. Photo courtesy of Tom Gore. Maintenance and Removal Inspection of silt fence includes observing the material for tears or holes and checking for slumping fence and undercut areas bypassing flows. Repair of silt fence typically involves replacing the damaged section with a new section. Sediment accumulated behind silt fence should be removed, as needed to maintain BMP effectiveness, typically before it reaches a depth of 6 inches. Silt fence may be removed when the upstream area has reached final stabilization. Silt Fence (SF) SC-1 November 2010 Urban Drainage and Flood Control District SF-3 Urban Storm Drainage Criteria Manual Volume 3 SC-1 Silt Fence (SF) SF-4 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Rock Sock (RS) SC-5 November 2010 Urban Drainage and Flood Control District RS-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph RS-1. Rock socks placed at regular intervals in a curb line can help reduce sediment loading to storm sewer inlets. Rock socks can also be used as perimeter controls. Description A rock sock is constructed of gravel that has been wrapped by wire mesh or a geotextile to form an elongated cylindrical filter. Rock socks are typically used either as a perimeter control or as part of inlet protection. When placed at angles in the curb line, rock socks are typically referred to as curb socks. Rock socks are intended to trap sediment from stormwater runoff that flows onto roadways as a result of construction activities. Appropriate Uses Rock socks can be used at the perimeter of a disturbed area to control localized sediment loading. A benefit of rock socks as opposed to other perimeter controls is that they do not have to be trenched or staked into the ground; therefore, they are often used on roadway construction projects where paved surfaces are present. Use rock socks in inlet protection applications when the construction of a roadway is substantially complete and the roadway has been directly connected to a receiving storm system. Design and Installation When rock socks are used as perimeter controls, the maximum recommended tributary drainage area per 100 lineal feet of rock socks is approximately 0.25 acres with disturbed slope length of up to 150 feet and a tributary slope gradient no steeper than 3:1. A rock sock design detail and notes are provided in Detail RS-1. Also see the Inlet Protection Fact Sheet for design and installation guidance when rock socks are used for inlet protection and in the curb line. When placed in the gutter adjacent to a curb, rock socks should protrude no more than two feet from the curb in order for traffic to pass safely. If located in a high traffic area, place construction markers to alert drivers and street maintenance workers of their presence. Maintenance and Removal Rock socks are susceptible to displacement and breaking due to vehicle traffic. Inspect rock socks for damage and repair or replace as necessary. Remove sediment by sweeping or vacuuming as needed to maintain the functionality of the BMP, typically when sediment has accumulated behind the rock sock to one-half of the sock's height. Once upstream stabilization is complete, rock socks and accumulated sediment should be removed and properly disposed. Rock Sock Functions Erosion Control No Sediment Control Yes Site/Material Management No SC-5 Rock Sock (RS) RS-2 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Rock Sock (RS) SC-5 November 2010 Urban Drainage and Flood Control District RS-3 Urban Storm Drainage Criteria Manual Volume 3 Inlet Protection (IP) SC-6 August 2013 Urban Drainage and Flood Control District IP-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph IP-1. Inlet protection for a curb opening inlet. Description Inlet protection consists of permeable barriers installed around an inlet to filter runoff and remove sediment prior to entering a storm drain inlet. Inlet protection can be constructed from rock socks, sediment control logs, silt fence, block and rock socks, or other materials approved by the local jurisdiction. Area inlets can also be protected by over-excavating around the inlet to form a sediment trap. Appropriate Uses Install protection at storm sewer inlets that are operable during construction. Consider the potential for tracked-out sediment or temporary stockpile areas to contribute sediment to inlets when determining which inlets must be protected. This may include inlets in the general proximity of the construction area, not limited to downgradient inlets. Inlet protection is not a stand-alone BMP and should be used in conjunction with other upgradient BMPs. Design and Installation To function effectively, inlet protection measures must be installed to ensure that flows do not bypass the inlet protection and enter the storm drain without treatment. However, designs must also enable the inlet to function without completely blocking flows into the inlet in a manner that causes localized flooding. When selecting the type of inlet protection, consider factors such as type of inlet (e.g., curb or area, sump or on-grade conditions), traffic, anticipated flows, ability to secure the BMP properly, safety and other site-specific conditions. For example, block and rock socks will be better suited to a curb and gutter along a roadway, as opposed to silt fence or sediment control logs, which cannot be properly secured in a curb and gutter setting, but are effective area inlet protection measures. Several inlet protection designs are provided in the Design Details. Additionally, a variety of proprietary products are available for inlet protection that may be approved for use by local governments. If proprietary products are used, design details and installation procedures from the manufacturer must be followed. Regardless of the type of inlet protection selected, inlet protection is most effective when combined with other BMPs such as curb socks and check dams. Inlet protection is often the last barrier before runoff enters the storm sewer or receiving water. Design details with notes are provided for these forms of inlet protection: IP-1. Block and Rock Sock Inlet Protection for Sump or On-grade Inlets IP-2. Curb (Rock) Socks Upstream of Inlet Protection, On-grade Inlets Inlet Protection (various forms) Functions Erosion Control No Sediment Control Yes Site/Material Management No SC-6 Inlet Protection (IP) IP-2 Urban Drainage and Flood Control District August 2013 Urban Storm Drainage Criteria Manual Volume 3 IP-3. Rock Sock Inlet Protection for Sump/Area Inlet IP-4. Silt Fence Inlet Protection for Sump/Area Inlet IP-5. Over-excavation Inlet Protection IP-6. Straw Bale Inlet Protection for Sump/Area Inlet CIP-1. Culvert Inlet Protection Propriety inlet protection devices should be installed in accordance with manufacturer specifications. More information is provided below on selecting inlet protection for sump and on-grade locations. Inlets Located in a Sump When applying inlet protection in sump conditions, it is important that the inlet continue to function during larger runoff events. For curb inlets, the maximum height of the protective barrier should be lower than the top of the curb opening to allow overflow into the inlet during larger storms without excessive localized flooding. If the inlet protection height is greater than the curb elevation, particularly if the filter becomes clogged with sediment, runoff will not enter the inlet and may bypass it, possibly causing localized flooding, public safety issues, and downstream erosion and damage from bypassed flows. Area inlets located in a sump setting can be protected through the use of silt fence, concrete block and rock socks (on paved surfaces), sediment control logs/straw wattles embedded in the adjacent soil and stacked around the area inlet (on pervious surfaces), over-excavation around the inlet, and proprietary products providing equivalent functions. Inlets Located on a Slope For curb and gutter inlets on paved sloping streets, block and rock sock inlet protection is recommended in conjunction with curb socks in the gutter leading to the inlet. For inlets located along unpaved roads, also see the Check Dam Fact Sheet. Maintenance and Removal Inspect inlet protection frequently. Inspection and maintenance guidance includes:  Inspect for tears that can result in sediment directly entering the inlet, as well as result in the contents of the BMP (e.g., gravel) washing into the inlet.  Check for improper installation resulting in untreated flows bypassing the BMP and directly entering the inlet or bypassing to an unprotected downstream inlet. For example, silt fence that has not been properly trenched around the inlet can result in flows under the silt fence and directly into the inlet.  Look for displaced BMPs that are no longer protecting the inlet. Displacement may occur following larger storm events that wash away or reposition the inlet protection. Traffic or equipment may also crush or displace the BMP.  Monitor sediment accumulation upgradient of the inlet protection. Inlet Protection (IP) SC-6 August 2013 Urban Drainage and Flood Control District IP-3 Urban Storm Drainage Criteria Manual Volume 3  Remove sediment accumulation from the area upstream of the inlet protection, as needed to maintain BMP effectiveness, typically when it reaches no more than half the storage capacity of the inlet protection. For silt fence, remove sediment when it accumulates to a depth of no more than 6 inches. Remove sediment accumulation from the area upstream of the inlet protection as needed to maintain the functionality of the BMP.  Propriety inlet protection devices should be inspected and maintained in accordance with manufacturer specifications. If proprietary inlet insert devices are used, sediment should be removed in a timely manner to prevent devices from breaking and spilling sediment into the storm drain. Inlet protection must be removed and properly disposed of when the drainage area for the inlet has reached final stabilization. SC-6 Inlet Protection (IP) IP-4 Urban Drainage and Flood Control District August 2013 Urban Storm Drainage Criteria Manual Volume 3 Inlet Protection (IP) SC-6 August 2013 Urban Drainage and Flood Control District IP-5 Urban Storm Drainage Criteria Manual Volume 3 SC-6 Inlet Protection (IP) IP-6 Urban Drainage and Flood Control District August 2013 Urban Storm Drainage Criteria Manual Volume 3 Inlet Protection (IP) SC-6 August 2013 Urban Drainage and Flood Control District IP-7 Urban Storm Drainage Criteria Manual Volume 3 SC-6 Inlet Protection (IP) IP-8 Urban Drainage and Flood Control District August 2013 Urban Storm Drainage Criteria Manual Volume 3 Protection of Existing Vegetation (PV) SM-2 November 2010 Urban Drainage and Flood Control District PV-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph PV-1. Protection of existing vegetation and a sensitive area. Photo courtesy of CDOT. Description Protection of existing vegetation on a construction site can be accomplished through installation of a construction fence around the area requiring protection. In cases where upgradient areas are disturbed, it may also be necessary to install perimeter controls to minimize sediment loading to sensitive areas such as wetlands. Existing vegetation may be designated for protection to maintain a stable surface cover as part of construction phasing, or vegetation may be protected in areas designated to remain in natural condition under post-development conditions (e.g., wetlands, mature trees, riparian areas, open space). Appropriate Uses Existing vegetation should be preserved for the maximum practical duration on a construction site through the use of effective construction phasing. Preserving vegetation helps to minimize erosion and can reduce revegetation costs following construction. Protection of wetland areas is required under the Clean Water Act, unless a permit has been obtained from the U.S. Army Corps of Engineers (USACE) allowing impacts in limited areas. If trees are to be protected as part of post-development landscaping, care must be taken to avoid several types of damage, some of which may not be apparent at the time of injury. Potential sources of injury include soil compaction during grading or due to construction traffic, direct equipment-related injury such as bark removal, branch breakage, surface grading and trenching, and soil cut and fill. In order to minimize injuries that may lead to immediate or later death of the tree, tree protection zones should be developed during site design, implemented at the beginning of a construction project, as well as continued during active construction. Design and Installation General Once an area has been designated as a preservation area, there should be no construction activity allowed within a set distance of the area. Clearly mark the area with construction fencing. Do not allow stockpiles, equipment, trailers or parking within the protected area. Guidelines to protect various types of existing vegetation follow. Protection of Existing Vegetation Functions Erosion Control Yes Sediment Control Moderate Site/Material Management Yes SM-2 Protection of Existing Vegetation (PV) PV-2 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Surface Cover During Phased Construction Install construction fencing or other perimeter controls around areas to be protected from clearing and grading as part of construction phasing. Maintaining surface cover on steep slopes for the maximum practical duration during construction is recommended. Open Space Preservation Where natural open space areas will be preserved as part of a development, it is important to install construction fencing around these areas to protect them from compaction. This is particularly important when areas with soils with high infiltration rates are preserved as part of LID designs. Preserved open space areas should not be used for staging and equipment storage. Wetlands and Riparian Areas Install a construction fence around the perimeter of the wetland or riparian (streamside vegetation) area to prevent access by equipment. In areas downgradient of disturbed areas, install a perimeter control such as silt fence, sediment control logs, or similar measure to minimize sediment loading to the wetland. Tree Protection 1  Before beginning construction operations, establish a tree protection zone around trees to be preserved by installing construction fences. Allow enough space from the trunk to protect the root zone from soil compaction and mechanical damage, and the branches from mechanical damage (see Table PV-1). If low branches will be kept, place the fence outside of the drip line. Where this is not possible, place fencing as far away from the trunk as possible. In order to maintain a healthy tree, be aware that about 60 percent of the tree's root zone extends beyond the drip line. Table PV-1 Guidelines for Determining the Tree Protection Zone (Source: Matheny and Clark, 1998; as cited in GreenCO and WWE 2008) Distance from Trunk (ft) per inch of DBH Species Tolerance to Damage Young Mature Over mature Good 0.5' 0.75' 1.0' Moderate 0.75' 1.0' 1.25' Poor 1.0' 1.25' 1.5' Notes: DBH = diameter at breast height (4.5 ft above grade); Young = <20% of life expectancy; Mature = 20%-80% of life expectancy; Over mature =>80% of life expectancy  Most tree roots grow within the top 12 to 18 inches of soil. Grade changes within the tree protection zone should be avoided where possible because seemingly minor grade changes can either smother 1 Tree Protection guidelines adapted from GreenCO and WWE (2008). Green Industry Best Management Practices (BMPs) for the Conservation and Protection of Water Resources in Colorado: Moving Toward Sustainability, Third Release. See www.greenco.org for more detailed guidance on tree preservation. Protection of Existing Vegetation (PV) SM-2 November 2010 Urban Drainage and Flood Control District PV-3 Urban Storm Drainage Criteria Manual Volume 3 roots (in fill situations) or damage roots (in cut situations). Consider small walls where needed to avoid grade changes in the tree protection zone.  Place and maintain a layer of mulch 4 to 6-inch thick from the tree trunk to the fencing, keeping a 6-inch space between the mulch and the trunk. Mulch helps to preserve moisture and decrease soil compaction if construction traffic is unavoidable. When planting operations are completed, the mulch may be reused throughout planting areas.  Limit access, if needed at all, and appoint one route as the main entrance and exit to the tree protection zone. Within the tree protection zone, do not allow any equipment to be stored, chemicals to be dumped, or construction activities to take place except fine grading, irrigation system installation, and planting operations. These activities should be conducted in consultation with a landscaping professional, following Green Industry BMPs.  Be aware that soil compaction can cause extreme damage to tree health that may appear gradually over a period of years. Soil compaction is easier to prevent than repair. Maintenance and Removal Repair or replace damaged or displaced fencing or other protective barriers around the vegetated area. If damage occurs to a tree, consult an arborist for guidance on how to care for the tree. If a tree in a designated preservation area is damaged beyond repair, remove and replace with a 2-inch diameter tree of the same or similar species. Construction equipment must not enter a wetland area, except as permitted by the U.S. Army Corps of Engineers (USACE). Inadvertent placement of fill in a wetland is a 404 permit violation and will require notification of the USACE. If damage to vegetation occurs in a protected area, reseed the area with the same or similar species, following the recommendations in the USDCM Revegetation chapter. Vehicle Tracking Control (VTC) SM-4 November 2010 Urban Drainage and Flood Control District VTC-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph VTC-1. A vehicle tracking control pad constructed with properly sized rock reduces off-site sediment tracking. Description Vehicle tracking controls provide stabilized construction site access where vehicles exit the site onto paved public roads. An effective vehicle tracking control helps remove sediment (mud or dirt) from vehicles, reducing tracking onto the paved surface. Appropriate Uses Implement a stabilized construction entrance or vehicle tracking control where frequent heavy vehicle traffic exits the construction site onto a paved roadway. An effective vehicle tracking control is particularly important during the following conditions:  Wet weather periods when mud is easily tracked off site.  During dry weather periods where dust is a concern.  When poorly drained, clayey soils are present on site. Although wheel washes are not required in designs of vehicle tracking controls, they may be needed at particularly muddy sites. Design and Installation Construct the vehicle tracking control on a level surface. Where feasible, grade the tracking control towards the construction site to reduce off-site runoff. Place signage, as needed, to direct construction vehicles to the designated exit through the vehicle tracking control. There are several different types of stabilized construction entrances including: VTC-1. Aggregate Vehicle Tracking Control. This is a coarse-aggregate surfaced pad underlain by a geotextile. This is the most common vehicle tracking control, and when properly maintained can be effective at removing sediment from vehicle tires. VTC-2. Vehicle Tracking Control with Construction Mat or Turf Reinforcement Mat. This type of control may be appropriate for site access at very small construction sites with low traffic volume over vegetated areas. Although this application does not typically remove sediment from vehicles, it helps protect existing vegetation and provides a stabilized entrance. Vehicle Tracking Control Functions Erosion Control Moderate Sediment Control Yes Site/Material Management Yes SM-4 Vehicle Tracking Control (VTC) VTC-2 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Photograph VTC-2. A vehicle tracking control pad with wheel wash facility. Photo courtesy of Tom Gore. VTC-3. Stabilized Construction Entrance/Exit with Wheel Wash. This is an aggregate pad, similar to VTC-1, but includes equipment for tire washing. The wheel wash equipment may be as simple as hand-held power washing equipment to more advance proprietary systems. When a wheel wash is provided, it is important to direct wash water to a sediment trap prior to discharge from the site. Vehicle tracking controls are sometimes installed in combination with a sediment trap to treat runoff. Maintenance and Removal Inspect the area for degradation and replace aggregate or material used for a stabilized entrance/exit as needed. If the area becomes clogged and ponds water, remove and dispose of excess sediment or replace material with a fresh layer of aggregate as necessary. With aggregate vehicle tracking controls, ensure rock and debris from this area do not enter the public right-of-way. Remove sediment that is tracked onto the public right of way daily or more frequently as needed. Excess sediment in the roadway indicates that the stabilized construction entrance needs maintenance. Ensure that drainage ditches at the entrance/exit area remain clear. A stabilized entrance should be removed only when there is no longer the potential for vehicle tracking to occur. This is typically after the site has been stabilized. When wheel wash equipment is used, be sure that the wash water is discharged to a sediment trap prior to discharge. Also inspect channels conveying the water from the wash area to the sediment trap and stabilize areas that may be eroding. When a construction entrance/exit is removed, excess sediment from the aggregate should be removed and disposed of appropriately. The entrance should be promptly stabilized with a permanent surface following removal, typically by paving. Vehicle Tracking Control (VTC) SM-4 November 2010 Urban Drainage and Flood Control District VTC-3 Urban Storm Drainage Criteria Manual Volume 3 SM-4 Vehicle Tracking Control (VTC) VTC-4 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Vehicle Tracking Control (VTC) SM-4 November 2010 Urban Drainage and Flood Control District VTC-5 Urban Storm Drainage Criteria Manual Volume 3 SM-4 Vehicle Tracking Control (VTC) VTC-6 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Street Sweeping and Vacuuming (SS) SM-7 November 2010 Urban Drainage and Flood Control District SS-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph SS-1. A street sweeper removes sediment and potential pollutants along the curb line at a construction site. Photo courtesy of Tom Gore. Description Street sweeping and vacuuming remove sediment that has been tracked onto roadways to reduce sediment transport into storm drain systems or a surface waterway. Appropriate Uses Use this practice at construction sites where vehicles may track sediment offsite onto paved roadways. Design and Installation Street sweeping or vacuuming should be conducted when there is noticeable sediment accumulation on roadways adjacent to the construction site. Typically, this will be concentrated at the entrance/exit to the construction site. Well-maintained stabilized construction entrances, vehicle tracking controls and tire wash facilities can help reduce the necessary frequency of street sweeping and vacuuming. On smaller construction sites, street sweeping can be conducted manually using a shovel and broom. Never wash accumulated sediment on roadways into storm drains. Maintenance and Removal  Inspect paved roads around the perimeter of the construction site on a daily basis and more frequently, as needed. Remove accumulated sediment, as needed.  Following street sweeping, check inlet protection that may have been displaced during street sweeping.  Inspect area to be swept for materials that may be hazardous prior to beginning sweeping operations. Street Sweeping/ Vacuuming Functions Erosion Control No Sediment Control Yes Site/Material Management Yes Drainage Plan PARCEL NO. 8708400064 OWNER: WILLIAM HOUSE ET AL PARCEL NO. 8708400057 OWNER: WILLIAM HOUSE ET AL LOT 1 AMENDED PLAT L 1-8, TRACT B & DOZIER DR PARCEL NO. 8708400034 OWNER: WILLIAM HOUSE ET AL PARCEL NO. 8709000008 OWNER: LUDIQUE CHAT, LLC PA R C E L N O . 8 7 0 9 0 0 0 9 4 0 OW N E R : L A K E C A N A L IR R I G A T I O N C O M P A N Y PARCEL NO. 8709307007 OWNER: MULBERRY SF LLC LAK E C A N A L DE L O Z I E R D R PROPOSED DETENTION POND PROPOSED DETENTION POND BLOOM FILING SIX LOT 1 LOT 3 LOT 2 OUTLOT A PROPOSED RAIN GARDEN FLAT AREA: 3,080 SF; VOLUME : 4040 CF TOP=4931'; BOTTOM=4930' LOT 4 PROPOSED RAIN GARDEN FLAT AREA: 1,735 SF; VOLUME : 2,520 CF TOP=4931'; BOTTOM=4930' EAST MULBERRY (HWY 14) FRONTAGE ROAD SHEET OF SHEETS BL O O M F I L I N G S I X CI T Y O F F O R T C O L L I N S , C O U N T Y O F L A R I M E R , S T A T E O F C O L O R A D O 18 FI N A L U T I L I T Y P L A N Know what's below. before you dig.Call R PRELIMINARY NOT FOR CONSTRUCTION 01/29/2025 OV E R A L L D R A I N A G E P L A N C-12 12 i2 LEGEND OF SYMBOLS BASIN RUNOFF SUMMARY DETENTION SUMMARY – ’. SURVEY NOTES ” FLOODPLAIN NOTES NOTES PERMANENT BMP (RAIN GARDEN) Sediment & Erosion Control Plan PARCEL NO. 8708400064 OWNER: WILLIAM HOUSE ET AL PARCEL NO. 8708400057 OWNER: WILLIAM HOUSE ET AL LOT 1 AMENDED PLAT L 1-8, TRACT B & DOZIER DR PARCEL NO. 8708400034 OWNER: WILLIAM HOUSE ET AL PARCEL NO. 8709000008 OWNER: LUDIQUE CHAT, LLC PA R C E L N O . 8 7 0 9 0 0 0 9 4 0 OW N E R : L A K E C A N A L IR R I G A T I O N C O M P A N Y PARCEL NO. 8709307007 OWNER: MULBERRY SF LLC LAK E C A N A L DE L O Z I E R D R EAST MULBERRY (HWY 14) FRONTAGE ROAD PROPOSED DETENTION POND PROPOSED DETENTION POND INTERIM INTERIM INITIAL INITIAL INTERIM INTERIM INTERIMINTERIM INTERIM INTERIM INTERIM INITIAL INITIAL INITIAL INITIAL INITIAL INITIAL INITIAL INTERIM INTERIM BLOOM FILING SIX LOT 3 LOT 2 OUTLOT A LOT 1 LOT 4 INTERIM INTERIMINTERIM INTERIM INTERIM INTERIM INTERIM INTERIM INTERIM INITIAL ONGOING ONGOING ONGOING FINAL FINAL FINAL LAK E C A N A L LA K E C A N A L INTERIM INTERIM INTERIM SHEET OF SHEETS BL O O M F I L I N G S I X CI T Y O F F O R T C O L L I N S , C O U N T Y O F L A R I M E R , S T A T E O F C O L O R A D O 18 FI N A L U T I L I T Y P L A N Know what's below. before you dig.Call R PRELIMINARY NOT FOR CONSTRUCTION 01/29/2025 SE D I M E N T & E R O S I O N C O N T R O L P L A N C-13 13 i2 LEGEND OF SYMBOLS TENTATIVE CONSTRUCTION SEQUENCE NOTES EROSON CONTROL TABLE – ’. SURVEY NOTES INITIAL/INTERIM/FINAL CDPHE Permit (Placeholder)