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HomeMy WebLinkAboutC31.0 STORM WATER POLLUTION PROTECTION PLANPLOT SCALE: 1:1 EDIT DATE: 7/22/21 - 1:45 PM EDITED BY: NFOSTER DRAWING FILE: Z:\PROJECTS\2020\0113 - ISLAMIC LIFE CENTER\2. DESIGN\CAD\STORM WATER POLLUTION PROTECTION PLAN.DWGPRINT DATE: 8/31/21STORM WATER POLLUTION PROTECTION PLANISLAMIC LIFE CENTER14120 Shelborne Road, Carmel IN 46074Al Salam FoundationDRAWN BY:CHECKED BY:TMJ 6280 N. Shadeland Avenue, Suite AIndianapolis, IN 46220Phone: (317) 598-6647 | www.theveridusgroup.comPROJECT NO.: 2020.0113 MWJ SWPPP FOR CONSTRUCTION SITES 1.14 DIGIT WATERSHED HYDROLOGIC UNIT CODE 05120201120070 2.NAME OF ALL RECEIVING WATERS Little Eagle Branch-Woodruff Branch is the ultimate receiving water for the project area. 3.PRE-CONSTRUCTION AND POST-CONSTRUCTION ESTIMATE OF PEAK DISCHARGE PRE-CONSTRUCTION 10-YEAR DISCHARGE: 1.14 CFS POST-CONSTRUCTION 10-YEAR DISCHARGE: 0.38 CFS 4.SPECIFIC POINT WHERE STORMWATER DISCHARGE WILL LEAVE THE SITE STORMWATER DRAINAGE FROM THE SITE WILL BE CONVEYED BY A PROPOSED STORM SEWER TO PROPOSED DRY DETENTION FACILITIES ALONG THE SOUTH SIDE OF THE SITE. THE DRY DETENTION FACILITIES WILL DISCHARGE TO AN EXISTING STORM SEWER SYSTEM ALONG THE WEST EDGE OF THE PROJECT SITE. 5.IDENTIFICATION OF ALL POTENTIAL DISCHARGES TO GROUND WATER THERE ARE NO LOCATIONS ON SITE WHERE SURFACE WATER MAY BE DISCHARGED INTO GROUND WATER. 6.SOILS MAP OF THE PREDOMINANT SOIL TYPES INCLUDING: a.Soil legend with descriptions of each soil type The Natural Resources Conservation Service (NRCS) Web Soil Survey of Hendricks County, Indiana, indicates Brookston Silty Clay, and Crosby Silt loam are located on the site. The full soil legend can be found on the Erosion Contol Plan. b.Brief description of how the site has accommodated the existing soil limitations The on-site soil will be treated as recommended by the geotechnical engineer if the conditions are unsuitable for the proposed construction. Remedial treatments may include, but are not limited to, removal of unsuitable soil and backfilling with engineered material, installation of a geofabric within or under the pavement system, or treatment of the subgrade with lime. 7.DESCRIPTION OF POTENTIAL POLLUTANT SOURCES ASSOCIATED WITH CONSTRUCTION ACTIVITIES The following potential pollutant sources may be associated with construction activities on site: ·Material storage areas (more specifically described below) ·Construction waste material ·Fuel storage areas and fueling stations ·Exposed soils ·Leaking vehicles and equipment ·Sanitary waste from temporary toilet facilities ·Litter ·Windblown dust ·Soil tracking off site from construction equipment The following construction materials may be staged or stored on site at various points during development of the site: ·Structural fill ·Pavement Base Stone ·HDPE, PVC, RCP or Ductile Iron pipe ·Precast concrete, HDPE or PVC drainage and sanitary structures ·Rock rip-rap 8.TEMPORARY AND PERMANENT STORMWATER QUALITY MEASURES: a.Location b.Dimensions c.Detailed specifications d.Construction details e.Monitoring and maintenance guidelines Refer to the Erosion Control Plan for locations of each stormwater quality measure and the Erosion Control Details. MONITORING AND MAINTENANCE GUIDELINES FOR EACH PROPOSED STORMWATER QUALITY MEASURE Inspection Schedule/Reporting All impacted areas, as well as all erosion and sediment control devices, will be inspected every seven (7) calendar days and within 24 hours after a rainfall of 0.5 inch or greater. Where sites have been final or temporarily stabilized or on sites where runoff is unlikely due to winter conditions (e.g., site is covered with snow, ice, or frozen ground exists), such inspections shall be conducted at least once every month. Inspections shall be conducted and a written report prepared, by a designated and qualified person familiar with the USEPA NPDES Storm Water General Permit, this SWPPP, and the Project. Inspection reports shall be completed including scope of the inspection, name(s) and qualifications of personnel making the inspection, the date of the inspection, observations relating to the implementation of the SWPPP, and any actions taken as a result of incidents of noncompliance noted during the inspection. The inspection report should state whether the site was in compliance or identify any incidents of noncompliance. The contractor shall keep a copy of the inspection reports on site and permanently for a period of two years following construction. The on-site reports may be requested by inspections conducted by the local governing authority. Construction Entrance Locations where vehicles exit the site shall be inspected for evidence of off-site sediment tracking. Each contractor and subcontractor shall be responsible for maintaining the Construction Entrance and other controls as described in this SWPPP. Material Storage Inspections Inspectors must evaluate areas used for storage of materials that are exposed to precipitation. The purpose is to ensure that materials are protected and/or impounded so that pollutants cannot discharge from storage areas. Off-site material storage areas used solely by the subject project are considered to be part of the project and must be included in the erosion control plans and the site inspection reports. Soil Stabilization Inspections Seeded areas will be inspected to confirm that a healthy stand of vegetation is maintained. The site has achieved final stabilization once all areas are covered with pavement or have a stand of vegetation with at least 70% of the background vegetation density. The density of 70% or greater must be maintained to be considered as stabilized. The operator or their representative will water, fertilize, and reseed disturbed areas as needed to achieve this goal. Erosion and Sediment Control Inspections All controls should be inspected at least once every seven (7) calendar days and following any storm event of 0.5 inch or greater. The following is a list of inspection/maintenance practices that will be used for specific controls: 1.Geotextiles/Erosion Control Mats: Missing or loose matting must be replaced or re-anchored. 2.Inlet Protection: If silt fence inlet protection is to be used, sediment should be removed when it reaches approximately one-half the height of the fence. If a sump is used, sediment should be removed when the volume of the basin is reduced by 50%. 3.Diversion Swales: Clean debris or other obstructions as needed. Damage from storms or normal construction activities (i.e., tire ruts) shall be repaired immediately. 4.Mulching: Inspect for thin or bare spots caused by natural decomposition or weather-related events. Mulch in high traffic areas should be replaced on a regular basis to maintain uniform protection. 5.Sediment Trap: Accumulated silt shall be removed and the basin shall be re-graded to its original dimensions at such point that the capacity of the impoundment has been reduced to one-half of its original storage capacity. The removed sediment shall be stockpiled or redistributed in areas that are protected from erosion. 6.Sediment Basin: Inspect frequently to check for damage and to ensure obstructions are not diminishing the effectiveness of the structures. Sediment shall be removed and the basin shall be re-graded to its original dimensions at such point that the capacity of the impoundment has been reduced to 20% of its original storage capacity. The removed sediment shall be stockpiled or redistributed in areas that are protected from erosion. 7.Silt Fence: Removal of built-up sediment will occur when the sediment reaches one-third the height of the fence. 8.Stabilized Construction Entrance: Periodic re-grading and top dressing with additional stone. 9.Straw Bales: Replace straw bales that show signs of deterioration. 10.Vegetation: Protect newly seeded areas from excessive runoff and traffic until vegetation is established. Establish a watering and fertilizing schedule. 11.Good Housekeeping: Litter, construction debris, and construction chemicals exposed to stormwater shall be prevented from becoming a pollutant source for stormwater discharges through screening of outfalls and daily pickup of litter. In the event that sediment escapes the construction site, off-site accumulations of sediment must be removed at a frequency sufficient to minimize adverse impacts. An example of this may be the situation where sediment has washed into the street and could be carried into the storm sewers by the next rainfall and/or pose a safety hazard to users of public streets. Modifications/Revisions to SWPPP. Based on inspection results, any necessary modification to this SWPPP shall be implemented within seven calendar days of the inspection. A modification is necessary if a control measure or operational procedure does not provide adequate pollutant control. All revisions shall be recorded on a Record of Revisions within seven calendar days of the inspection. It is the responsibility of the operator to maintain effective pollutant discharge controls. Physical site conditions or contractor/subcontractor practices could make it necessary to install more controls than were originally planned. For example, localized concentrations of surface runoff or unusually steep areas could require additional silt barrier or other structural controls. Assessing the need for and installing additional controls will be a continuing contractor/subcontractor responsibility until final stabilization is achieved. Contractors and subcontractors implementing this SWPPP must remain alert to the need to periodically refine and update this SWPPP in order to accomplish the intended goals. Notice of Termination Compliance of the site with the General Construction Permit remains the responsibility of all operators that have submitted an NOI until such time as they have submitted a Notice of Termination (NOT). The permittee's authorization to discharge under the General Construction Permit terminates at midnight of the day the NOT is signed. All permittees must submit an NOT within thirty (30) days after one or more of the following conditions have been met: 1.Final stabilization has been achieved on all portions of the site for which the permittee was responsible. 2.Another operator/permittee has assumed control over all areas of the site that have not been finally stabilized. 3.In residential construction operations, temporary stabilization has been completed and the residence has been transferred to the homeowner. 9.GENERAL CONSTRUCTION SEQUENCE Each plan should contain multiple stormwater pollution prevention measures. All measures will not be installed at the same time. Various measures will be installed at different times throughout the construction process. Some will be installed prior to land disturbance, and others may not be installed until work at the site progresses to an area where they are necessary. Each proposed measure should be identified in the sequence as to when it is to be installed in relation to the land disturbing activities. continuing contractor/subcontractor responsibility until final stabilization is achieved. Contractors and subcontractors implementing this SWPPP must remain alert to the need to periodically refine and update this SWPPP in order to accomplish the intended goals. SEQUENCE DESCRIBING STORMWATER QUALITY MEASURE IMPLEMENTATION RELATIVE TO LAND-DISTURBING ACTIVITIES 1.Schedule pre-construction meeting with local stormwater authority. 2.Install construction entrance. 3.Utilize the gravel construction entrance for installation of the perimeter silt fence. Add stone if needed. Post the NOI at the entrance. Add protection measures to existing inlets. 4.Install staging area, fueling station, material storage area and concrete truck washout. 5.Strip the top soil and grade. 6.Complete the cut and fills on the site. Final grade and seed the pond slopes. Install check dams or stabilize the slopes with erosion control blankets. 7.Prior to building construction install stone surface for paved areas. 8.Building pads left dormant for more than 15 days, must be temporarily seeded. 9.Start building construction. Install staging area for building materials. 10.Install storm sewer and other utilities. Provide inlet protection immediately upon completion of the inlet and install riprap outlet protection prior to installing outlets. Final grade and stabilize slopes when inlets are functioning. 11.Seed the perimeter of the site. 12.Complete utility installation, curbs, paving and building construction. 13.Install landscaping plant material and stabilize all disturbed areas. 14.Remove all erosion and sediment control practices when areas have a uniform grass cover. Stable construction entrance locations and specifications Construction entrances will be in place prior to any site construction or demolition. Entrances are shown on the Erosion Control Plan, refer to the Erosion Control Details for details. Sediment control measures for sheet flow areas Sheet flow areas will be protected by seed and mulch or hydroseeding. Erosion control blankets will be installed on sloped areas where the slope exceeds 6:1 (horizontal to vertical). Silt Fencing will be utilized to prevent sedimentation from leaving the site. Refer to the Erosion Control Plan for locations and the Erosion Control Details for details. Sediment control measures for concentrated flow areas Proposed swales will be stabilized with erosion control blankets, and rock donuts will be installed to slow runoff to inlets. Straw bales and silt fences will not be allowed as concentrated flow protection measures. Refer to the Erosion Control Plan for locations and the Erosion Control Details for details. Storm sewer inlet protection measure locations and specifications The contractor shall install appropriate inlet protection measures at each inlet. Refer to the Erosion Control Plan for locations and the Erosion Control Details for details. Straw bales will not be allowed as inlet protection measures. Runoff control measures Temporary, permanent seeding, erosion ground cover and erosion rolls will be placed during construction as runoff control measures. Stormwater outlet protection specifications Stormwater outlets will be protected by riprap aprons to prevent scour erosion. Refer to the Erosion Control Plan for locations and the Erosion Control Details for details. Grade stabilization structure locations and specifications Rip rap aprons at outlets will be utilized to prevent grade destabilization. Refer to the Erosion Control Plan for locations and the Erosion Control Details for details. 10.LOCATION OF PROPOSED SOIL STOCKPILES, BORROW, AND/OR DISPOSAL AREAS Excess soil shall be immediately stockpiled, surrounded with silt fence and seeded and/or removed from the construction site in accordance with all applicable laws. If topsoil stockpiles are anticipated for this project, they are shown on the Erosion Control Plan. 11.TEMPORARY AND PERMANENT SURFACE STABILIZATION METHODS APPROPRIATE FOR EACH SEASON Surface stabilization is required on any bare or thinly vegetated area that is scheduled or likely to remain inactive for a period of 15 days or more. Refer to the Temporary Seeding Detail within Erosion Control Details for specifics on soil amendments, seed mixtures and mulching. A. Loosen lawn area to a minimum depth of 6 inches. Mix soil amendments and fertilizers with topsoil at rates specified. Organic soil amendments such as peat, compost or manure shall be applied at 2" depth evenly over soil and incorporated into the top 6" of topsoil.Provide fertilizer with percentage of nitrogen required to provide not less than 1 pound of actual nitrogen per 1,000 sq. ft. of lawn area and not less than 4 percent phosphoric acid and 2 percent potassium. At least 50 percent of nitrogen to be organic form. Delay mixing of fertilizer if planting will not follow placing of planting soil within a few days. B. Fertilizer for lawns: provide a fast release fertilizer with a composition of 1 lb per 1,000 sq. ft. of actual nitrogen, 4 percent phosphorous, and 2 percent potassium by weight. C.low-release fertilizer for trees and shrubs: granular fertilizer consisting of 50 percent water-insoluble nitrogen, phosphorous and potassium made up of a composition by weight of 5 percent D. Grade lawn and grass areas to a smooth, even surface with loose, uniformly fine texture. Limit fine grading to areas that can be planted within immediate future. Remove trash, debris, stones larger than 1 inch diameter, and other objects that may interfere with planting or maintenance operations. Sow seed using a spreader or seeding machine. Do not seed when wind velocity exceeds 5 miles per hour. E.Distribute seed evenly over entire area by sowing equal quantity in 2 directions at right angles to each other. F.Rake seed lightly into top 1/8 inch of soil, roll lightly, and water with a fine spray. G.Install erosion control blankets as indicated on the plan. H.Protect seeded areas against erosion by spreading clean, seed-free straw mulch after completion of seeding operations. Spread uniformly to form a continuous blanket not less than 1-1/2 inches loose measurements over seeded areas. I.Water newly planted lawn areas and keep moist until new grass is established. Immediately repair any lawn areas disturbed by construction activities including tree and shrub installation. J.Refer to the Permanent Seeding Details within the Erosion Control Detail Sheet, for timing of permanent seeding, grass seed specifications and mulching specifications. 12.EROSION AND SEDIMENT CONTROL SPECIFICATIONS FOR INDIVIDUAL LOTS This site will not be subdivided; therefore, there are no individual lots on the property. The proposed site improvements are shown on the included plans. 13.MATERIAL HANDLING, STORAGE, AND SPILL PREVENTION PLAN a.List of expected materials that may be present on the site during construction operations b.Written description of how these materials will be handled to minimize the potential of entering the storm sewer system c.Procedures for the contractor to take if any spills occur during construction. Solid Waste Disposal No solid material, including building materials, is permitted to be discharged to surface waters or buried on site. All solid waste materials, including disposable materials incidental to the construction activity, must be collected in containers or closed dumpsters. The collection containers must be emptied periodically and the collected material hauled to a landfill permitted by the State and/or appropriate local municipality to accept the waste for disposal. A foreman or supervisor should be designated in writing to oversee, enforce, and instruct construction workers on proper solid waste procedures. Hazardous Waste Whenever possible, minimize the use of hazardous materials and generation of hazardous wastes. All hazardous waste materials will be disposed in the manner specified by federal, state, or local regulations or by the manufacturer. Use containment berms in fueling and maintenance areas and where potential for spills is high. A foreman or supervisor should be designated in writing to oversee, enforce and instruct construction workers on proper hazardous waste procedures. The location of any hazardous waste storage areas should be indicated on the stormwater pollution prevention plan by the operator following on-site location of the facility. Dust Control/Off-Site Vehicle Tracking During construction, water trucks should be used, as needed, by each contractor or subcontractor to reduce dust. After construction, the site should be stabilized to reduce dust. Construction traffic should enter and exit the site at a Construction Entrance with a rock pad or equivalent device. The purpose of the rock pad is to minimize the amount of soil and mud that is tracked onto existing streets. If sediment escapes the construction site, off-site accumulations of sediment must be removed at a frequency sufficient to minimize offsite impacts. Sanitary/Septic Contractors and subcontractors must comply with all state and local sanitary sewer, portable toilet, or septic system regulations. Sanitary facilities shall be provided at the site by each contractor or subcontractor throughout construction activities. The sanitary facilities should be utilized by all construction personnel and be serviced regularly. All expenses associated with providing sanitary facilities are the responsibility of the contractors and subcontractors. The location of any sanitary facilities should be indicated on the stormwater pollution prevention plan by the operator following on-site location of said facilities. Water Source Water used to establish and maintain grass, to control dust, and for other construction purposes must originate from a public water supply or private well approved by the State or local health department. Equipment Fueling and Storage Areas Equipment fueling, maintenance, and cleaning should only be completed in protected areas (i.e., bermed area). Leaking equipment and maintenance fluids will be collected and not allowed to discharge onto soil where they may be washed away during a rain event. Equipment wash down (except for wheel washes) should take place within an area surrounded by a berm. The use of detergents is prohibited. Hazardous Material Storage Chemicals, paints, solvents, fertilizers, and other toxic or hazardous materials should be stored in their original containers (if original container is not resealable, store the products in clearly labeled, waterproof containers). Except during application, the containers should be kept in trucks or in bermed areas within covered storage facilities. Runoff containing such materials shall be collected, removed from the site, and disposed of in accordance with the federal, state, and local regulations. As may be required by federal, state or local regulations, the Contractor should have a Hazardous Materials Management Plan and/or Hazardous Materials Spill and Prevention Program in place. A foreman or supervisor should be designated in writing to oversee, enforce, and instruct construction workers on proper hazardous materials storage and handling procedures. The location of any hazardous material storage areas should be indicated on the stormwater pollution prevention plan by the operator following on-site location of the storage areas. Material Handling and Spill Prevention Discharge of hazardous substances or oil into stormwater is subject to reporting requirements. In the event of a spill of a hazardous substance, the operator is required to notify the National Response Center (1-800-424-8802) to properly report the spill. In addition, the operator shall submit a written description of the release (including the type and amount of material released, the date of the release, the circumstances of the release, and the steps to be taken to prevent future spills) to the local governing authority. The SWPPP must be revised within 14 calendar days after the release to reflect the release, stating the information above along with modifications to minimize the possibility of future occurrences. Each contractor and subcontractor is responsible for complying with these reporting requirements. Concrete Washout All concrete trucks waste material shall be completely contained and disposed in accordance with all local, state, and federal regulations. A pit or container is required when cleaning concrete chutes. Spill Response Plan Minor - Small spills that typically involve oil, gasoline, paint, hydraulic fluid, etc., can be controlled by the first responder at the discovery of the spill. ·Contain spill to prevent material from entering storm or ground water. Do not flush with water or bury. ·Use absorbent material to clean-up spill material and any subsequently contaminated soil and dispose of properly. ·Semi-Significant Spills - Approximately ten gallons or less of pollutant with no contamination of ground or surface waters. Minor spills can be generally controlled by the first responder with help from other site personnel. This response may require other operations to stop to make sure the spill is quickly and safely addressed. At the discovery of the spill: ·Contain spill to prevent material from entering storm or ground water. Do not flush with water or bury. ·Use absorbent material to clean-up spills and dispose of properly. Spills on impervious surfaces should be disposed of as soon as possible to prevent migration deeper into the soil and groundwater. Dispose of contaminated soils or absorbents properly. ·Contact 911 if the spill could be a safety issue. ·Contact supervisors and designated site inspectors immediately. ·Contaminated solids are to be removed to an approved landfill. ·Major or Hazardous Spills - More than ten gallons, there is the potential for death, injury or illness to humans or animals, or has the potential for surface or groundwater pollution. ·Control or contain the spill without risking bodily harm. Temporarily plug storm drains if possible to prevent migration of the spill into the stormwater system. ·Immediately contact the local Fire Department at 911 to report any hazardous material spill. ·Contact supervisors and designated site inspectors immediately. Governing authorities responsible for storm water facilities should be contacted as well. The contractor is responsible for having these contact numbers available at the job site. A written report should be submitted to the owner as soon as possible. ·As soon as possible but within 2 hours of discovery, contact the local agency responsible for spill management. The following information should be noted for future reports to the agency: ··Name, address and phone number of person making the spill report ··The location of the spill ··The time of the spill ··Identification of the spilled substance ··Approximate quantity of the substance that has been spilled or may be further spilled ··The duration and source of the spill ··Name and location of the damaged waters ··Name of spill response organization ··What measures were taken in the spill response ··Other information that may be significant Additional regulations or requirements may be present. A spill response professional should be consulted to make sure all appropriate and required steps have been taken. Contaminated solids should only be removed from the site after approval is given by the appropriate agency. 14.CONTACT INFORMATION FOR THE TRAINED INDIVIDUAL RESPONSIBLE FOR STORMWATER POLLUTION PREVENTION FOR THE PROJECT SITE a.Name - TBD b.Address - TBD c.Telephone number -TBD d.E-mail address - TBD e.List of qualifications - TBD 15.CURRENT REVISION DATE ON ALL SHEETS Refer to the Title Block. SWPPP FOR POST-CONSTRUCTION 1.DESCRIPTION OF POTENTIAL POLLUTANT SOURCES ASSOCIATED WITH THE PROPOSED LAND USE. The proposed land use is an Islamic Worship Center. The pollutants and sources of each pollutant normally expected from this type of land use are listed below: Pollutant Source: Passenger vehicles, delivery vehicles. Type of Pollutant: Oil, gasoline, diesel fuel, any hydrocarbon associated with vehicular fuels and lubricants, grease, antifreeze, windshield cleaner solution, brake fluid, brake dust, rubber, glass, metal and plastic fragments, grit, road de-icing materials. Pollutant Source: Building Type of Pollutant: Cleaning solutions or solvents, leaks from HVAC equipment, grit from roof drainage, aggregate or rubber fragments from roofing system. Pollutant Source: Trash dumpster Type of Pollutant: Cleaning solutions or solvents, litter (paper, plastic, general refuse associated with distribution operations), uneaten food products, bacteria. Pollutant Source: Parking lot Type of Pollutant: Any pollutant associated with vehicular sources, grit from asphalt wearing surface, bituminous compounds from periodic maintenance (sealing, resurfacing and patching), pavement de-icing materials, paint fragments from parking stall stripes, concrete fragments, wind-blown litter from off-site sources, elevated water temperatures from contact with impervious surfaces. Pollutant Source: Lawn and landscape areas Type of Pollutant: Fertilizers, soil, organic material (leaves, mulch, grass clippings) 2.POST-CONSTRUCTION STORMWATER QUALITY MEASURES: The following items are stormwater quality measures that will be installed during construction. These items will remain in place after construction is completed and are considered to serve an incidental function as post-construction stormwater quality BMPs. Dry detention pond, native vegetation, Aquaswirl Model AS-8, and the vegetated swale will remain on site as water quality measures. Refer to Utility Plan/Details for more information. 3.SEQUENCE DESCRIBING STORMWATER QUALITY MEASURE IMPLEMENTATION The stormwater detention pond and BMP will remain in place as permanent features after construction is completed. The purpose of the these measures is to restrict stormwater discharges and provide a sediment removal function. 4.STORMWATER QUALITY MEASURES TO BE IMPLEMENTED TO PREVENT OR MINIMIZE ADVERSE IMPACTS TO STREAM AND RIPARIAN HABITATS Permanent Vegetation Topsoil will be placed in lawn areas and seeded with grass, and graded not to exceed 3:1 slopes. Proposed landscape trees and shrubs will also be added. These Bio areas will act as a natural filter strip to help improve storm water quality. The vegetated areas will slow the velocities of storm water runoff, reduce sediment runoff, and reduce problems associated with mud or dust from bare soils. Dry Detention Basin Basins collect, temporarily hold, and gradually release excess storm water from storm events. Detention is achieved through the use of an outlet structure that regulates the rate of storm water outflow. Mechanical BMP (Aqua-swirl, etc.) A BMP structure will be installed at the downstream end of the storm sewer system, prior to the storm sewer outlet. The primary purpose of the BMP is to remove sediment, oils and floatable debris from the stormwater prior to discharging from the site. Good Housekeeping Measures Good Housekeeping measures such as regular street sweeping, installation of trash receptacles, and reduction in fertilizer overspray can be incorporated by the owner and/or occupant. 5.AN OPERATION AND MAINTENANCE MANUAL FOR ALL POST-CONSTRUCTION STORMWATER QUALITY MEASURES: An operation and maintenance manual has been completed and included as apart of these plans. C31