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HomeMy WebLinkAboutFORT COLLINS MONTESSORI SCHOOL - SPA190003 - SUBMITTAL DOCUMENTS - ROUND 1 - STORMWATER MANAGEMENT PLANPrepared For: Hauser Architects, P.C. 3780 East 15th Street, Suite 201 Loveland, CO 80538 970-669-8220 Prepared By: Coffey Engineering & Surveying, LLC 4045 St. Cloud Drive, Suite 180 Loveland, CO 80538 970-622-2095 Contractor/SWMP Administrator: Elder Construction Inc. 7380 Greendale Road Windsor, CO 80550 970-744-4731 Owner: Fort Collins Montessori School Project No. 2259.03 October 18, 2019 STORMWATER MANAGEMENT PLAN FORT COLLINS MONTESSORI SCHOOL 1109 W HARMONY FORT COLLINS, CO 80526 STORMWATER MANAGEMENT PLAN FOR FORT COLLINS MONTESSORI SCHOOL 2 I. Table of Contents I. Table of Contents ................................................................................................... 2 II. Introduction .................................................................................................... 1 1.1 Stormwater Quality Statement ............................................................................... 1 1.2 SWMP Objective ...................................................................................................... 1 1.3 Location .................................................................................................................... 1 1.4 Project Description .................................................................................................. 2 III. Site Description ............................................................................................... 2 2.1 Construction Activity Description .......................................................................... 2 2.2 Proposed Sequence for Major Activities................................................................ 2 2.3 Area Estimates ......................................................................................................... 3 2.4 Runoff Coefficient and Soil Description ................................................................ 3 2.5 Existing Vegetation .................................................................................................. 3 2.6 Location and Description of Other Potential Pollution Sources ......................... 3 2.7 Non-Stormwater Components of Discharge .......................................................... 4 2.8 Receiving Waters ..................................................................................................... 4 IV. BMPs for Stormwater Pollution Prevention ................................................ 4 3.1 Erosion and Sediment Controls .............................................................................. 4 3.2 Erosion Control Sequencing ................................................................................... 6 3.3 Materials Handling and Spill Prevention .............................................................. 7 V. Potential pollutant sources............................................................................. 8 VI. Final Stabilization and Long-term Stormwater Quality ..........................10 VII. Inspection and Maintenance Procedures ...................................................11 VIII. References ......................................................................................................12 IX. APPENDIX A ................................................................................................13 STORMWATER MANAGEMENT PLAN FOR FORT COLLINS MONTESSORI SCHOOL 1 II. INTRODUCTION 1.1 Stormwater Quality Statement Stormwater quality best management practices shall be implemented to minimize soil erosion, sedimentation, increased pollutant loads and changed water flow characteristics resulting from land disturbing activity, to the maximum extent practicable, so as to minimize pollution of receiving waters. 1.2 SWMP Objective The objective of this Stormwater Management Plan (SWMP) for Fort Collins Montessori, is to identify the Best Management Practices (BMP’s) which, when implemented, will meet the requirements of the City of Fort Collins SWMP Standards. The SWMP goal is to, “Identify possible pollutant sources that may contribute pollutants to stormwater, and identify BMP’s that, when implemented, will reduce or eliminate any possible water quality impacts. 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, BMP’s selected, documented, implemented, and pollutant sources be re-evaluated (and the process continued). 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 SWMP Administrator for the site. The SWMP Administrator 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. References are found in the Appendix regarding some of the requirements, restrictions, and forms related to the SWMP. 1.3 Location The proposed site is located in the northeast quarter (NE ¼) of Section 3, Township 6 North, Range 69 West of the 6th P.M., City of Fort Collins, County of Larimer, State of Colorado and can legally be described as Lot 1 Montessori Subdivision. The site’s parcel number is 960310008 and has GPS coordinates of 40.522890, -105.097053. Specifically, the property is located southwest of the intersection of West Harmony Road and South Shields Street. The property address is 1109 West Harmony Road, Fort Collins, Colorado, 80526. (Please see the vicinity map located in the Appendix A). STORMWATER MANAGEMENT PLAN FOR FORT COLLINS MONTESSORI SCHOOL 2 1.4 Project Description The site is 4.29 acres currently zoned as low-density mixed-use neighborhood district (LMN). The existing site consists of a residence, detached garage, various outbuildings, gravel access drive and native vegetation. The site is bound by Harmony Road to the north, Shields Street to the east, and residential lots to the south and west. The existing site is comprised of two sub-basins. The northern portion of the site, approximately 2.17 acres, drains to the northeast corner of the site at a slope of approximately 3 percent to an existing 3’x3’ area inlet. The southern portion of the site, approximately 2.12 acres, sheet flows to the south onto the adjacent property. According to the NRCS soils map survey, the native soils consist of Altvan-Satanta Loams (a United States Department of Agriculture Type “B” hydrologic soil). These soils have a moderate rate of water transmission. This soil has a K value of 0.28. The higher the K value the more susceptible to erosion. K values range from 0.02 to 0.69. There are no active irrigation facilities located within the proposed site area. The development of the site will occur in two phases. This SWMP will address the improvements for only phase I. The development of phase I consists of the construction of a 14,700-sf Montessori school, two temporary modular buildings, concrete sidewalks, playground area, right turn lane off Shields Street and landscaping improvements. Parking will be provided to the north of the proposed building on an asphalt parking lot with concrete curb and gutter allowing for site drainage. The site will utilize four on-site detention ponds connected by equalizer pipes. The detention ponds were designed to accommodate developed flows from both phases of development. III. SITE DESCRIPTION 2.1 Construction Activity Description Construction activity includes installation of BMP’s, grading, utility construction, and building and parking lot construction. 2.2 Proposed Sequence for Major Activities The sequence for major construction activities includes the installation of BMP’s, overlot grading including drainage conveyance construction, installation of utilities, building construction, final grading and landscaping. Construction is expected to occur in one phase. Construction is estimated to begin January 2020 and be completed in June 2020. STORMWATER MANAGEMENT PLAN FOR FORT COLLINS MONTESSORI SCHOOL 3 2.3 Area Estimates The entire site area, 4.29 acres will be disturbed and will be referred to as the, “Limit of disturbance.” The staging & storage area will be approximately 10,000 square feet. The approximate cut/fill number is 8,000 cubic yards of cut. 2.4 Runoff Coefficient and Soil Description According to the NRCS Web Soil Survey maps, the majority of the site consists of: Name Soil Type Erosion Altvan-Satanta Loams, 0 to 3 Percent Slope B Moderate 2.5 Existing Vegetation The site consists of approximately 90% native vegetation ground cover with mature trees scattered around the site. The remaining portion of the site consists of an existing residence, various out buildings, and a gravel driveway. 2.6 Location and Description of Other Potential Pollution Sources Potential pollutant sources include water and wind born sediment, uncovered soil, concrete washouts, building materials, and fertilizers. Reference the Erosion Control Plan STORMWATER MANAGEMENT PLAN FOR FORT COLLINS MONTESSORI SCHOOL 4 in the Appendix 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. 2.7 Non-Stormwater Components of Discharge Site disturbance will not exceed five feet below the existing grade, therefore having no impact on the groundwater at lower depths. 2.8 Receiving Waters The proposed site is located within the Mail Creek Basin, located in southwest Fort Collins. The basin has a drainage area of approximately 1676 acres and is primarily located between Taft Hill Road and Lemay Avenue between Horsetooth Road and County Road 36. The basin generally drains from west to east to the confluence of Mail Creek and Fossil Creek, and ultimately to Fossil Creek Reservoir. Fossil Creek is approximately 4.25 miles from the proposed site. IV. BMPS FOR STORMWATER POLLUTION PREVENTION 3.1 Erosion and Sediment Controls In order for construction activities to begin, Best Management Practices (BMP’s) intended to contain sediment onsite must be constructed, inspected and repaired as necessary. Such controls must be functional before upslope land disturbance takes place. The BMP’s will be installed as shown on the enclosed Erosion Control Plan. They must be supplemented as on-site experience proves necessary in order to control sediment, pollutant discharge, and ensure public safety. The following temporary and permanent BMP’s will be installed and maintained to control on-site erosion and prevent sediment from traveling off-site during construction: Temporary BMP’s • Temporary Seeding is the establishment of a temporary vegetative cover on a graded area that will be exposed for longer 30 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. • Vehicle Tracking Control (shown as VTC on the 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 STORMWATER MANAGEMENT PLAN FOR FORT COLLINS MONTESSORI SCHOOL 5 to the minimum number necessary to provide functional construction access and installed prior to overlot grading activities. Whenever the construction entrance exists onto a road, the road shall be cleaned at the end of each day. • Silt Fence (shown as SF on the 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. • Concrete Washout Area (shown as CWA on the 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. • Rock Sock (shown as RS on the Erosion Control Plan) is a temporary BMP that is constructed of gravel that has been wrapped by wire mesh or 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. Rock socks can be used at the perimeter of a disturbed area or along small concentrated flow paths to control localized sediment loading. Cones should be placed near Rock Socks in heavy traffic areas to minimize damage from vehicles. • Wind Borne Sediment and Dust Control measures will be provided during the construction process to control wind borne sediment. During grading activities, water will 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. Please reference the City of Fort Collins “Dust Prevention and Control Manual”. STORMWATER MANAGEMENT PLAN FOR FORT COLLINS MONTESSORI SCHOOL 6 Permanent BMP’s • Permanent Seeding and Planting 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. • 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. Only land needed for building activities and vehicle traffic needs to be cleared. For this site, the existing trees will be preserved, while the rest of the existing vegetation will be removed. • Linear Bioretention (Bioswale): Linear bioretention has low longitudinal slopes and broad cross-sections that convey flow in a slow and shallow manner, thereby facilitating sedimentation and filtering while limiting erosion. Berms or check dams may be incorporated into the facility to reduce velocities and encourage settling and infiltration. Linear bioretention is an integral part of the LID concept. • Extended Detention Basin: An extended detention basin (EDB) is a sedimentation basin designed to detain stormwater for many hours after storm runoff ends. This BMP is similar to a detention basin used for flood control, however; the EBD uses a much smaller outlet that extends the emptying time of the more frequently occurring runoff events to facilitate pollutant removal. 3.2 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. For this site, the existing trees and bushes will be preserved as noted on the engineering and landscape plans. Inlet/Gutter Protection/Rock Socks – Rock socks will be placed at curb inlets and gutters located adjacent to the site immediately prior to earth disturbing activities, if applicable. Silt Fence – Before earth disturbing activities, silt fence will be placed downstream of areas where runoff from construction activities are expected to occur. In particular for this site, silt fence will be place downstream of the proposed stockpile area (if applicable). Silt fence will be placed near the curb on the east side of the site. STORMWATER MANAGEMENT PLAN FOR FORT COLLINS MONTESSORI SCHOOL 7 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. It 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 all dust generating activities. Slope Protection – Surface roughening, and contour furrows shall occur after rough grading. For this site, the majority of steeper slopes that may require surface roughening are shown on the grading and erosion control plans. 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. Temporary Seeding – The majority of the landscaped areas will be permanently seeded/planted. However, if the roadways/parking lots do not have base course placed on them or the lots are left disturbed without permanent stabilization 30 days after grading, temporary seeding will be required. Post Construction Refer to Final Stabilization and Long-term Stormwater Quality below. 3.3 Materials Handling and Spill Prevention The site development will include the appropriate construction staging areas. Stormwater runoff generated from the staging areas will be routed to a temporary sedimentation area where runoff will be contained and filtered before being discharged off site. Reference the Erosion Control Plan in the Appendix for the location of the staging area (as applicable). 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. Chemicals, fuels, lubricants, and paints typical with building construction stored on-site will 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 building materials, fertilizers, waterline, sanitary sewer, and storm STORMWATER MANAGEMENT PLAN FOR FORT COLLINS MONTESSORI SCHOOL 8 sewer will be covered and placed on pallets to prevent direct contact with the ground and potential surface runoff. Other hazardous waste disposal (that is not typical to commercial building 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 will be disposed of properly. The SWMP Administrator should be notified of spills. V. POTENTIAL POLLUTANT SOURCES Solid waste materials, including disposable materials incidental to the major construction activities, will be collected in containers. The containers will be emptied periodically and trucked 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 Colorado Department of Public Health and Environment 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. Locate toilet facilities approximately 50 ft. away from storm drain inlets and waterways to prevent accidental spills and contamination of stormwater. Provide tie-downs or stake-downs for portable toilets. All Disturbed and Stored Soils: The site disturbs 4.26 acres of land. Silt fence around the perimeter of the site and rock socks along curb and gutter will be used to prevent sediment leaving the site. Vehicle Tracking of Sediments: A vehicle tracking pad is to be installed at the northwest entrance along Harmony Road. At the end of each workday the contractor is to sweep the south flowline of Harmony Road to remove any sediment in the street. Management of Contaminated Soils: Please reference Section 3.3 Materials Handling and Spill Prevention. Loading and Unloading Operations: Steps should be taken to minimize the movement of soil from the site. Contractors and laborers shall park in specified areas on-site. When loading/unloading equipment from vehicles, load/near the site entrance, to minimize the movement of soil from the site. STORMWATER MANAGEMENT PLAN FOR FORT COLLINS MONTESSORI SCHOOL 9 Outdoor Storage Activities: Contractor to determine the best location for outdoor storage. Outdoor storage is to be surrounded by silt fence with vehicle tracking control at the entrance. Vehicle and Equipment Maintenance and Fueling: All vehicles and equipment will be fueled offsite, before arriving to the site. Maintenance and repair of vehicles and equipment will also occur offsite. Significant Dust or Particulate Generating Processes/Saw Cutting and Grinding: Dust will be prevented from leaving the site by the silt fence. To mitigate on-site dust, water will be used at the end of each workday on temporary areas that are prone to produce dust, or straw is to be matted over areas of long-term risk. Street saw cuts will be required along Harmony Road and Shields Street. These saws generate a significant amount of dust. Watering the cutting surface to prevent airborne particulates (BMP in the City’s Fugitive Dust Manual) is required. The cutting slurry has a high content of fine particulates (Silica Dust, Metals, etc.) that is not allowed to discharge as runoff from the site. To prevent slurry from discharging offsite, contractors will use the minimum amount of water needed to prevent dust and blades from overheating (site management control). Cutting slurry will be collected via vacuum or allowed to dry out and be scraped and swept up after the cutting has finished (saw cutting). Routine Maintenance Activities Involving Fertilizer, Pesticides, Detergents, Fuels, Solvents, Oils, etc: Fertilizers and Pesticides will be used during the later phases of the project when trying to establish a healthy vegetation. These chemicals are highly water soluble and are easily and unnoticeably carried in the stormwater. Proper application rates and recommended timing of application will be strictly followed and not on days, or the next day, where the weather is calling for precipitation (materials management control). As most of these types of chemicals will be brought on by the landscaper, they will be required to keep these products in their vehicles until time of application and not be allowed to leave these materials on the site. If these materials are stored on site, they shall be kept inside or outside covered and above the ground to prevent the materials from mixing with water and runoff (materials management control). Detergents, paints, acids, cement, grout, and solvents will be prevalent in the interior work of the building (materials management). These materials also are typically easily mixed with water yet are typically noticeable by discolored, cloudy, or sudsy water. As such, the contractor will always keep an eye out for these types of differences in water around the site (site management control). However, these materials are to be handled, operated, and cleaned up all within the inside of the structure, where external use is concerned these materials will be stored in the construction connex box, trailers, vehicles, or the like out of contact with precipitation (materials management). If not stored in a location as described secondary containment will be required (materials management). Fuels and oils might be associated with the smaller equipment used on site, chainsaws, pumps, generators, etc. As petroleum products are easily suspended in water and are spread across the top of the water surface. These products when located in water have rainbow sheen on them. They are also monitored during construction (site management controls). These products will be stored in the construction connex box, trailers, vehicles, or similar structure that will minimize contact with precipitation (materials maintenance controls). If not stored in a location as described secondary containment will be required (materials maintenance). Any untreated runoff from these activities can be detrimental to wildlife if not cleaned up. STORMWATER MANAGEMENT PLAN FOR FORT COLLINS MONTESSORI SCHOOL 10 On-site Waste Management Practices: Contractor to provide location of waste material stockpile, with the knowledge that any stockpile is to be a minimum of 50 feet from any inlet structures or watercourses. Concrete Truck/Equipment Washing, Including the Concrete Truck Chute and Associated Fixtures and Equipment: See Erosion Control Plan for the location of the concrete washout area. All excess concrete is to be disposed of in the concrete washout area. Non-industrial Waste Sources Such as Worker Trash and Portable Toilets: On-site dumpster and portable toilet are to be placed by contractor with the knowledge that they must be 50 feet from any inlet structure or watercourses. Other Areas or Procedures where Potential Spills can Occur: The water table was not encounter in the first 10 feet. Dewatering will not be anticipated for this site. Waste Management and Contaminated Soils Removal: All contaminated soils must be removed from the site to prevent on-site disposal of solid waste. 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. When construction is complete, debris, unused stockpiles and materials should be recycled or properly disposed. In some cases, this will require disposal of contaminated soil from equipment leaks in an appropriate landfill. 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. Construction-related materials, debris and waste must be removed from the construction site once construction is complete. Trash and bulk waste-collection areas on-site will be designated with appropriate signs. Dedicated Concrete and Asphalt Batch Plants: There will not be any dedicated asphalt or concrete batch plants on-site. VI. 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 the City of Fort Collins Stormwater Standards Manual. Upon final stabilization, temporary BMP’s may be removed, unless they are required to remain in place for future phasing. STORMWATER MANAGEMENT PLAN FOR FORT COLLINS MONTESSORI SCHOOL 11 Soil amendments shall be provided and documented in accordance with City Code Section 12- 132. The soil in all landscape areas, including parkways and medians, shall be thoroughly loosened to a depth of no less than eight inches and soil amendment shall be thoroughly incorporated into the soil of all landscape areas to a depth of at least six inches by tilling, discing or other suitable method, at a rate of at least three cubic yards of soil amendment per one thousand square feet of landscape area. Prior to the issuance of any certificate of occupancy, a written certification must be submitted to the city that all planted areas, or areas to be planted, have been thoroughly loosened and the soil amended, consistent with the requirements set forth in Section 12-132. To the maximum extent feasible, topsoil that is removed during construction activity shall be conserved for later use on areas requiring revegetation and landscaping. Areas disturbed shall be reseeded. Please see the approved Landscaping Plan. VII. INSPECTION AND MAINTENANCE PROCEDURES The temporary BMP’s will be inspected and documented at a minimum of once every 14 days and within 24 hours after each precipitation or snowmelt event. The SWMP will 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 City of Fort Collins Stormwater Standards Manual, 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 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 added to. The following includes some maintenance procedures: • Erosion and sediment control measures determined, upon inspection, to be in need of repair shall be maintained as soon as site is accessible on items or areas identified in the inspection report. Most repairs should be completed within 24 to 48 hours. STORMWATER MANAGEMENT PLAN FOR FORT COLLINS MONTESSORI SCHOOL 12 • 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 before it can be conveyed to the receiving storm drains or creeks. • Rock at inlet protection will be checked regularly for sediment buildup which will prevent drainage. If the rock is clogged with silt, it will be removed and cleaned or replaced. • Seeded areas will be checked to see that grass coverage is maintained. Areas will be watered, fertilized and reseeded as needed. • It is the responsibility of the Operator 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 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. This plan intends 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. • Sediment that has escaped the construction site must be removed at a frequency sufficient to minimize off-site impacts. VIII. REFERENCES “Fort Collins Stormwater Criteria Manual”, City of Fort Collins, Adopted December 2018 Natural Resources Conservation Service Web Soil Survey at websoilsurvey.nrcs.usda.gov/app Urban Storm Drainage Criteria Manual, Volumes 1, 2, and 3, Urban Drainage and Flood Control District, April 2008 STORMWATER MANAGEMENT PLAN FOR FORT COLLINS MONTESSORI SCHOOL 13 IX. APPENDIX A • Vicinity Map • Soils Report • SWMP Escrow • Erosion Control Plan • Erosion Control Details Soil Map—Larimer County Area, Colorado Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 8/28/2019 Page 1 of 3 4485700 4485720 4485740 4485760 4485780 4485800 4485820 4485840 4485860 4485880 4485900 4485700 4485720 4485740 4485760 4485780 4485800 4485820 4485840 4485860 4485880 4485900 491690 491710 491730 491750 491770 491790 491810 491830 491850 491690 491710 491730 491750 491770 491790 491810 491830 491850 40° 31' 25'' N 105° 5' 53'' W 40° 31' 25'' N 105° 5' 46'' W 40° 31' 18'' N 105° 5' 53'' W 40° 31' 18'' N 105° 5' 46'' W N Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 13N WGS84 0 50 100 200 300 Feet 0 15 30 60 90 Meters Map Scale: 1:1,050 if printed on A portrait (8.5" x 11") sheet. Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Map Unit Polygons Soil Map Unit Lines Soil Map Unit Points Special Point Features Blowout Borrow Pit Clay Spot Closed Depression Gravel Pit Gravelly Spot Landfill Lava Flow Marsh or swamp Mine or Quarry Miscellaneous Water Perennial Water Rock Outcrop Saline Spot Sandy Spot Severely Eroded Spot Sinkhole Slide or Slip Sodic Spot Spoil Area Stony Spot Very Stony Spot Wet Spot Other Special Line Features Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI 3 Altvan-Satanta loams, 0 to 3 percent slopes 4.7 100.0% Totals for Area of Interest 4.7 100.0% Soil Map—Larimer County Area, Colorado Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 8/28/2019 Page 3 of 3 Project: Disturbed Acres: 4.26 Reseeded Area: 2.00 EROSION CONTROL BMPs Units Estimated Quantity Unit Price Total Price Ea. 7 $150.00 $1,050.00 Ea. 8 $100.00 $800.00 Ea. 1 $928.00 $928.00 Ea. 1 $1,750.00 $1,750.00 Ea. 2 $150.00 $300.00 LF 1150 $1.90 $2,185.00 Sub-Total: $7,013.00 1.5 x Sub-Total: $10,519.50 Amount of security: $10,519.50 Total Acres x Price/acre: $2,180.00 $1,090.00 Sub-Total: $2,180.00 1.5 x Sub-Total: $3,270.00 Amount to Re-seed: $3,270.00 Minimum escrow amount: $3,000.00 Erosion Control Escrow: $10,519.50 Erosion and Sediment Control Escrow/Security Calculation for The City of Fort Collins BMP Amount Vehical Tracking Pad Reseeding Amount Inlet Protection Silt Fence Miniumum Escrow Amount Fort Collins Montessori School Unit Price of Seeding per acre: “The amount of the security must be based on one and one-half times the estimate of the cost to install the approved measures, or one and one-half times the cost to re-vegetate the disturbed land to dry land grasses based upon unit cost determined by the City's Annual Revegetation and Stabilization Bid, whichever is greater. In no instance, will the amount of security be less than one thousand five hundred dollars ($1,500) for residential development or three thousand dollars ($3,000) for commercial development” Rock Sock (Curb) Concrete Washout Area Final Escrow Amount Waddle Dike 10/21/2019 3:55 PM R:\2200\2259.03 Fort Collins Montessori School\HYDRO\Stormwater Management Plan\FCMS SWPM Escrow.xls ONLY N UTILITY PLANS FOR FORT COLLINS MONTESSORI SCHOOL ENGINEERING & SURVEYING 4045 St. Cloud Drive, Suite 180 Loveland, CO 80538 [P] 970-622-2095 [F] 970-461-4469 1109 W HARMONY ROAD NE1 4 OF SECTION 3, T6N, R69W, 6TH P.M., CITY OF FORT COLLINS, COUNTY OF LARIMER, STATE OF COLORADO DWG. NAME 15 NO. REVISION DATE SHEET NO. OF PROJECT: DATE: DESIGNER: DRAFTER: CHECKED BY: APPROVED BY: 2259.03 09/07/18 TWC TWC NOT FOR CONSTRUCTION PRELIMINARY Know what's below. Call before you dig. R BENCHMARK STATEMENT LEGEND: DRAINAGE & EROSION CONTROL PLAN C-11 11 ___ ___ CITY OF FORT COLLINS, COLORADO UTILITY PLAN APPROVAL PROPOSED BASIN FLOWS STANDARD EROSION AND SEDIMENT CONSTRUCTION PLAN NOTES EROSION BMP LEGEND DETENTION SUMMARY & REMOVAL OF BMP'S SEQUENCE FOR INSTALLATION UTILITY PLANS FOR FORT COLLINS MONTESSORI SCHOOL ENGINEERING & SURVEYING 4045 St. Cloud Drive, Suite 180 Loveland, CO 80538 [P] 970-622-2095 [F] 970-461-4469 1109 W HARMONY ROAD NE1 4 OF SECTION 3, T6N, R69W, 6TH P.M., CITY OF FORT COLLINS, COUNTY OF LARIMER, STATE OF COLORADO DWG. NAME 15 NO. REVISION DATE SHEET NO. OF PROJECT: DATE: DESIGNER: DRAFTER: CHECKED BY: APPROVED BY: 2259.03 09/07/18 TWC TWC NOT FOR CONSTRUCTION PRELIMINARY Know what's below. Call before you dig. R DETAIL SHEET 3 C-14 14 RJP RJP 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 13, Sep 10, 2018 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Aug 11, 2018—Aug 12, 2018 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Soil Map—Larimer County Area, Colorado Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 8/28/2019 Page 2 of 3