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HomeMy WebLinkAboutAVAGO TECHNOLOGIES BLDG. 4 WEST EXPANSION - MJA/FDP - FDP130006 - SUBMITTAL DOCUMENTS - ROUND 2 - DRAINAGE REPORT (3)AVAGO TECHNOLOGIES – BUILDING 4 WEST ANNEX EXPANSION AND SITE DEVELOPMENT EROSION CONTROL REPORT / STORMWATER MANAGEMENT REPORT CITY OF FORT COLLINS, COLORADO REV. MAY 21st, 2013 MARCH 25TH, 2013 MARTIN/MARTIN PROJECT NO. 13.0091 FDP 130006 PREPARED FOR: AVAGO TECHNOLOGIES (APPLICANT) 4380 ZIEGLER ROAD FORT COLLINS, CO 8025-9790 (970) 288-0344 PAUL TANGUAY PREPARED BY: MARTIN/MARTIN, INC. 12499 WEST COLFAX AVENUE LAKEWOOD, COLORADO 80215 PHONE: (303) 431-6100 PRINCIPAL IN CHARGE: MATTHEW B. SCHLAGETER, P.E. PROJECT MANAGER: PETER S. BUCKLEY, P.E. 303-431-6100 x246 PROJECT ENGINEER: BRET M. SMITH, E.I.T. II 2 A. GENERAL REQUIREMENTS................................................................ 4 PROJECT LOCATION:................................................................................................ 5 NATURE AND PURPOSE OF CONSTRUCTION ACTIVITY: ................................ 6 EXISTING CONDITIONS: .......................................................................................... 6 DISTURBED AREA ESTIMATES: ............................................................................. 6 EXISTING PERCENT VEGETATION GROUND COVER: ..................................... 6 EXISTING SOIL TYPE / EROSION POTENTIAL: .................................................. 6 RECEIVING WATERS:................................................................................................ 7 ANTICIPATED ALLOWABLE SOURCES OF NON-STORMWATER DISCHARGE:................................................................................................................ 9 PROPOSED PHASES FOR MAJOR ACTIVITIES: .................................................. 9 B. STORMWATER MANAGEMENT CONTORLS: ................................ 10 SWMP ADMINISTRATOR: ....................................................................................... 10 IDENTIFICATION OF POTENTIAL POLLUTANT SOURCES:.......................... 11 DESCRIPTION OF STRUCTURAL AND NON-STRUCTURAL BMP’S .............. 15 C. SEQUENCED BMP IMPLEMENTATION.......................................... 21 GENERAL.................................................................................................................... 21 INITIAL ....................................................................................................................... 21 INTERIM..................................................................................................................... 22 FINAL .......................................................................................................................... 23 D. INSPECTION AND MAINTENANCE PROCEDURES ..................... 24 E. FINAL STABILIZATION...................................................................... 25 SOIL AMMENDMENTS ............................................................................................ 25 3 PERMANENT SEED MIX ......................................................................................... 26 F. REFERENCES ....................................................................................... 27 4 A. GENERAL REQUIREMENTS This report represents a Stormwater Management Plan (SWMP) for the proposed Avago Technologies - Building 4 West Annex Expansion and Site Development (hereafter referred to as “PROJECT”). This plan was prepared based upon the regulatory requirements and guidelines set forth by the Colorado Department of Public Health and Environment Water Quality Control Division – Stormwater Program’s “Stormwater Management Plan Preparation Guidance” April 2011 revision; the “Urban Storm Drainage Criteria Manual – Volume 3”, current revision, the City of Fort Collins Standards and Specifications, and the document provided by the City of Fort Collins entitled “RE: Erosion Control Report and Drawing Requirements Accompanying Document”. This report identifies potential sources of pollution which may reasonably be expected to affect the quality of stormwater discharges associated with construction. Furthermore, this report describes the practices to be used to reduce, or possibly eliminate, these potential pollutants from impacting the quality of water. The SWMP shall be completed and implemented by the time construction activities begin until final stabilization. The SWMP shall be revised as necessary during construction activities so that it accurately reflects the conditions and current practices found on site as construction progresses. A copy of the current updated SWMP shall be kept on site at all times and available for review by all jurisdictions having authority over stormwater discharge from the project site. This report puts forth recommendations for Best Management Practices (BMPs) and provides a description and/or detailed drawings of how these practices are to be installed, implemented and maintained. The contractor is responsible for complying with ALL requirements of the Colorado Department of Health and Safety’s Storm Water Discharge Permit including any changes to this SWMP to meet the requirements of the Permit. 5 PROJECT LOCATION: The PROJECT site is located on the Hewlett-Packard Campus (hereafter referred to as “CAMPUS”) in Lot 2 of the Preston-Kelley 2 nd Subdivision, found in the Southwest ¼ of Section 33, Township 7 North, Range 68 West of the 6 th Principal Meridian, City of Fort Collins, County of Larimer, State of Colorado. The PROJECT address is 4380 Ziegler Road. The overall site consists of 8.80 acres of disturbed area. The overall CAMPUS is bound to the north by Hidden Pond Drive, to the east by the Fossil Creek Drainage Ditch, to the south by East Harmony Road, and to the west by Ziegler Road. The PROJECT site is bound to the north by an existing field and Technology Parkway (“Ring Road”), to the east by the existing Hewlett Packard Building 4, to the south by existing landscaped areas and an asphalt parking lot, and to the west by Technology Parkway. Refer to the vicinity map below and in the Appendix. Figure 1: Vicinity Map, NTS 6 NATURE AND PURPOSE OF CONSTRUCTION ACTIVITY: The proposed development will include the construction of an expansion to the existing Building 4, private asphalt and concrete drives, and utility infrastructure necessary to service the proposed building. The footprint of the building expansion covers approximately 80,000 SF. Additionally, drainage facilities designed to improve Stormwater Quality are proposed for the site in accordance with Section 3.4.3 Water Quality of the City of Fort Collins Municipal Code. EXISTING CONDITIONS: The existing site topography generally slopes from west to east at approximately 0.7 percent. Native grasses or existing asphalt drives and parking cover a large majority of the site. A large portion of the existing parking lot located west of the Building 4 Expansion footprint is proposed for demolition in order to maintain compliance with the “Hewlett-Packard Building 4 Drainage Report”, by Sear-Brown Group, 1999. DISTURBED AREA ESTIMATES: Total Site Area: 14.91 Acres Total Area Disturbed: 14.91 Acres EXISTING PERCENT VEGETATION GROUND COVER: The existing vegetative cover consists of landscaped areas with short grasses, trees, and shrubs in the existing islands, medians, and landscaped areas in front of existing buildings. These existing landscaped areas are estimated to have 98-100% vegetation ground cover. Additionally, large native areas are located west of the proposed Building 4 Expansion footprint. These native areas are estimated to have 50% vegetation ground cover. EXISTING SOIL TYPE / EROSION POTENTIAL: According to the “Geotechnical Engineering Report” produced by Terracon Consultants, Inc., dated September 4, 2012, the existing soils consist of fill materials consisting of sandy lean clay with various amounts of sand and gravel, and in-situ poorly graded sand 7 with gravel. Based on the results of borings, claystone bedrock is located at a maximum depth of exploration of 39.7 feet. Groundwater was observed at a maximum elevation of 4982.6’, and a minimum depth of 18’ below existing grade. The soils on site are typically SCS Type C Hydrologic Soils. Type C soils generally exhibit a high potential for runoff during rainfall which may lead to an increased probability for erosion. A USDA web soil survey of the CAMPUS states that the soils consist mostly of Nunn clay loam. A copy of the web soil survey is referenced in the Appendix. RECEIVING WATERS: According to the City of Fort Collins website, the CAMPUS belongs to the Fox Meadows Drainage Basin, which encompasses approximately 2.4 square miles in southeast Fort Collins. The Basin is bound by Horsetooth Road on the north, Lemay Avenue on the west, Harmony Road on the south, and the Cache La Poudre River on the east. The basin is primarily developed with residential development, some commercial areas and the Collindale Golf Course. The basin does not include a major drainageway for conveying flows through the basin. Storm runoff flows through a network of storm sewers, local drainage channels and detention ponds from west to east; ultimately discharging into the Cache La Poudre River. The PROJECT site is specifically divided into two historic basins - North and South. The majority of the proposed PROJECT site discharges north to a regional channel. The channel was designed for the 100-year storm and discharges to the North Pond on the CAMPUS. Stormwater detention and water quality treatment for the CAMPUS is provided by four on-site ponds located in the SE corner of the CAMPUS. These ponds are constructed as Extended Detention Basins (EDBs). The North Pond is a dry bottom pond. The South Pond, Southwest Pond, and Dam Pond are wet ponds. From the regional channel, runoff enters the CAMPUS North Pond, which then flows into the South Pond, which then flows into the Dam Pond before flowing off-site and eventually into the Cache La Poudre River. Added water quality benefits are gained via the regional channel along the north side of the campus which is constructed as a Grass Swale. This channel provides initial water quality treatment to the north-flowing basins in the PROJECT area prior to treatment in the CAMPUS ponds. 8 Runoff from the southern portion of the PROJECT site is conveyed via on-site storm sewer into the CAMPUS Southeast Pond, which then flows into the South Pond, which then flows into the Dam Pond before flowing off-site and eventually into the Cache La Poudre River. Figure 2: Major Drainage Basin 9 ANTICIPATED ALLOWABLE SOURCES OF NON-STORMWATER DISCHARGE: In addition to discharge from storm water, landscape irrigation return flows may be anticipated from tributary landscaped areas. There are no wetlands or springs anticipated to contribute to site discharge. PROPOSED PHASES FOR MAJOR ACTIVITIES: *Note: The following is a general overview of major construction phases. For a detailed review of specific activities and associated BMPs, refer to the Construction Sequencing Charts on the erosion control plans and in Section C of this report. Phase 1: The first phase of construction activity on the B4 West Annex project will include selective demolition, clear and grub, over-lot grading, and some underground utility construction. This is tentatively scheduled to begin on June 24 th 2013. Prior to any of the aforementioned activities beginning all BMPs will be installed per the erosion control drawings and details. Once installed and inspected by J.E. Dunn Construction Phase 1 activity will begin. The major BMPs in place during phase one will include S- Fence, VTC, Concrete Washout, existing Inlet Protection as required, and Stockpile management and protection. Target Start: 6/24/2013 Target Completion: 7/24/13 Phase 2: The second phase of construction activities will include major foundation activities, under-slab MEP activities and the balance of underground utility activities. This phase will begin immediately following the completion of over-lot grading. All BMPs will be maintained during this phase of construction with the VTC and CWA BMPs seeing increased activity as a result of concrete operation. Stockpile activity during this phase will be minimal. Any additional BMPs required of our interim erosion control plan will be installed at this time and will be maintained until stabilization activities begin. 10 Target Start: 7/24/13 Target Completion: 1/5/2014 Phase 3: Phase three of the B4 West Annex Project will include all enclosure activities. This will include steel and pre-cast deliveries and erection. This will also include any exterior curtain wall or metal panel installation as required. Roofing activities will also be completed during this time in order to provide a dry building. No changes to interim BMPs should be expected but all BMPs will be maintained as required during phase 3 construction. Target Start: 12/1/14 Target Completion: 4/1/14 Phase 4: The final phase of activity for the B4 West Annex project is miscellaneous interior build-out and site-work activities. This will also include final selective demolition, site grading, and landscaping activities. Stockpile management and protection will re-occur during this phase as well. Stockpile management and protection locations shall be redlined on the final erosion control plan at as necessary during this phase. Finally, near the end of Phase 4, stabilization activities will begin and final BMPs will be placed. Target Start: 4/1/14 Target Completion: 7/1/14 B. STORMWATER MANAGEMENT CONTORLS: SWMP ADMINISTRATOR: Mike Disler, Superintendent J.E. Dunn Construction Company 2000 S. Colorado Blvd., Suite 12000 Denver, CO, 80222 11 The SWMP administrator shall be responsible for developing, implementing, maintaining, and revising the SWMP. IDENTIFICATION OF POTENTIAL POLLUTANT SOURCES: The potential for each of the possible pollutant sources to contribute pollutants to storm water discharge in the list below have been evaluated with regards to the frequency of the activity, the physical characteristic of the area, the ability of containment measure to prevent and contain leaks and/or spills, proximity to waterways or drainage facilities, the concentration and toxicity of materials and the possible contamination of storage facilities and materials. If it was determined that the source has a reasonable chance of contributing pollutants to storm water discharge, a specific BMP or combination of BMPs has been identified to address or mitigate that potential. All Disturbed and Stored Soils: Disturbed Area: 14.91 acres Location of Stockpile: Proposed stockpile locations have been shown on the plans. At the discretion of the SWMP Administrator, actual stockpile locations may vary during construction; however, the current location of stockpiles shall be accurately reflected by redlining the construction plan set. Disturbed Soils: Soils disturbed during construction activities (grading, foundation excavation, utility trenching, etc.) have the potential to introduce sediment into runoff. Silt fence will be used to prevent sediment from leaving down-gradient of disturbed areas. Surface roughening will be used to stabilize disturbed areas after 14 days. Temporary seeding and mulching will be used to stabilize disturbed areas after 30 days. Inlet protection will be used to help prevent sediment from entering storm sewer. Street sweeping shall be performed daily when disturbed soils have tracked onto paved streets. Construction fence will be used to minimize access to undisturbed areas and limit the area of disturbed soil. Rock socks will be used at sidewalk chase outfalls in order to catch sediment from concentrated runoff. 12 BMP’s: Temporary and Permanent Seeding, Mulching, Stockpile Management, Silt Fence, Inlet Protection, Street Sweeping and Vacuuming, Construction Fence, Surface Roughening, Rock Socks Demolition of Existing Structures: Demolition of existing structures will produce visible dust, debris and waste requiring proper containment and disposal. Demolition activities on the B4 West Annex Job include: selective demolition of the existing Building 4 west wall for new addition, utility demolition within proposed expansion footprint, and demolition of asphalt and concrete paved areas to provide for the new building site. S-Fence will be used to ensure no sediment leaves the site. Silt fence will be placed down gradient of the proposed demolition in order to provide a barrier to catch sediment from runoff leaving the site. BMPs: Spill Prevention and Containment, Inlet Protection, Good Housekeeping, Construction Fence. Vehicle Tracking of Sediment: In order to prevent sediment from leaving the site via exiting vehicles, a vehicle tracking control pad shall be used for site access. Construction fence shall be used to limit access to the site from any area other than through the vehicle tracking control pad. Street sweeping shall occur whenever sediment is carried onto the street from the site. Nearby inlets shall be protected. BMP’s: Vehicle Tracking Control, Construction Fence, Street Sweeping and Vacuuming, Inlet Protection Management of Contaminated Soils: Pre-existing contaminated soils are not anticipated. The following BMP’s shall be implemented to prevent contamination, and control contamination in the event of a spill: BMP’s: Good Housekeeping Practices, Stabilized Staging Area, Spill Prevention, Containment and Control 13 Loading and Unloading Operations: Loading and unloading operations can result in particulate generation, which can be carried off the site and ultimately collected by runoff. BMP’s: Where possible, dump trucks and waste trucks entering/exiting the site shall be covered. The property shall be watered to avoid particulate generation from loading/unloading. Loading and unloading shall take place on the Stabilized Staging Area and away from inlets. Outdoor Storage Activities: Wherever possible, chemicals shall be stored in a covered location to prevent rainwater from directly impacting storage containers. The spill prevention, containment, and control BMP shall be utilized minimize risks from storing chemicals outside. All workers on the site shall be trained in spill prevention, containment, and control. Building materials shall be stored on the Stabilized Staging Area in order to minimize erosion while accessing stored materials. BMP’s: Spill Prevention, Containment, and Control, Stabilized Staging Area Vehicle and Equipment Maintenance and Fueling: On-site vehicle equipment maintenance and fueling increases the risk for spilling the chemicals used for these activities. Where practical, these activities should occur off-site. When on-site fueling and maintenance is warranted, it shall occur on the stabilized staging area. The location of the stabilized staging area is shown on the erosion control plans. If the location of the stabilized staging area is moved during construction, the updated location shall be redlined on the approved erosion control plan set. BMP’s: Good Housekeeping Practices, Stabilized Staging Area, Spill Prevention, Containment and Control Sawcutting: Sawcutting asphalt and concrete has the potential to introduce sediment into stormwater runoff. Downstream inlets shall be protected. Plan sawcutting for days when dry weather is expected. Do not wash any paved surface into receiving storm drain inlets or natural 14 drainageways. Instead, loose material should be swept or vacuumed following sawcutting operations. BMP’s: Street Sweeping and Vacuuming Significant Dust or Particulate Generating Processes: Dump Trucks and waste trucks shall be covered whenever possible. Water shall be used to minimize particulate generation. The City of Fort Collins requires that the site be continuously watered in order to minimize particulate generation from wind. If particulate accumulation results in sediment deposit outside of the site, street sweeping should occur immediately. BMP’s: Street Sweeping and Vacuuming Routine maintenance activities involving fertilizers, pesticides, detergents, fuels, solvents, oil, etc: Wherever possible, chemicals shall be stored in a covered location to prevent rainwater from directly impacting storage containers. The spill prevention, containment, and control BMP shall be utilized to minimize risks from storing chemicals outside. Workers on the site shall be trained in spill prevention, containment, and control. Additionally, wherever possible, chemicals should be used away from storm inlets and/or natural drainageways. For example, refueling should take place at least 50’ away from storm sewer inlets. BMP’s: Spill Prevention, Containment, and Control On-site waste management practices: Trash, demolition debris, and waste can be carried by storm water runoff and/or wind, contaminating runoff water, and clogging existing facilities. To mitigate this risk, dumpster should be closed whenever feasible. Dumpsters and/or waste piles shall be located a minimum of 50ft from any inlet structures or watercourses. Inspection of dumpsters for leaks should occur with weekly SWMP inspections. BMP’s: Good Housekeeping Practices 15 Dedicated asphalt and concrete batch plants: No dedicated asphalt or concrete batch plants will be used on site. BMP’s: None. Concrete truck/equipment washing, including the concrete truck chute and associated fixtures and equipment: Concrete waste including waste produced after washing trucks, pumps, and associated fixtures and equipment can be easily tracked onto adjacent streets with the potential to contaminate stormwater runoff. Concrete washout areas are specifically indicated on the plans and should be located a minimum of 50ft from any inlet structures or watercourses. At the discretion of the SWMP Administrator, actual concrete washout locations may vary during construction; however, the current location of concrete washouts shall be accurately reflected by redlining the construction plan set. BMP’s: Concrete Washout Area Non-industrial waste sources such as workers trash and portable toilets: Good housekeeping shall be practiced on site in order to eliminate stormwater contamination risk from worker trash and portable toilets. Provide an adequate amount of trash bins in order to encourage compliance across all workers. Stake portable toilets to the ground in order to minimize the risk of overturning. Updated portable toilet locations shall be redlined on the construction plan set. Portable toilets shall be located a minimum of 50ft from any inlet structures or watercourses. BMP’s: Good Housekeeping DESCRIPTION OF STRUCTURAL AND NON-STRUCTURAL BMP’S In addition to the descriptions below, the contractor is encouraged to refer to the “Urban Storm Drainage Criteria Manual – Volume 3” for comprehensive BMP information 16 Temporary and Permanent Seeding (TS/PS) Final stabilization for landscaped areas will be achieved when vegetation has achieved cover which matches the existing vegetative cover. Because a large area of native grass will be replaced with permanent seeding, vegetative cover is expected to be improved from existing conditions as a result of the proposed development. If temporary seeding becomes necessary (any disturbed area which has not reached final stabilization within 30 days), the following seed mix or approved equal shall be used: The use of mulch in conjunction with temporary seeding shall be required to help protect the seedbed and stabilize the soil. Clean, weed- and seed-free, long-stemmed grass hay is preferred because it is less susceptible to removal by wind. Mulch should be applied evenly at a rate of 2 tons per acre and must be tacked or fastened by an approved method suitable for the type of mulch used. At least 50 percent of the grass hay mulch, by weight, should be 10 inches or more in length. Good Housekeeping Practices (GH) Good housekeeping is a source control BMP. Good housekeeping practices are designed to maintain a clean and orderly work environment. Poor housekeeping practices result in increased waste and potential for stormwater contamination. A cleaned and orderly work site reduces the possibility of accidental spills caused by mishandling of chemicals and equipment. Vehicle Tracking Control (VTC) Vehicle Tracking Control is a sediment removal device for construction equipment and vehicles entering/exiting the site (as described in the UDFCD criteria). Vehicle tracking 17 control pads shall be installed at the single access point to the site (at the west drive cut for the Ring Road) prior to any land-disturbing activity. VTC pads shall be maintained in working order according to the VTC detail in the erosion control plans. Stabilized Staging Area (SSA) The stabilized staging area shall be used for parking, storage, and unloading and loading operations. The SSA shall consist of 3” minimum thickness of granular material, and shall be large enough to fully contain parking, storage, and unloading and loading operations. For this PROJECT site, the existing asphalt parking lot will be used as a SSA until demolition. After demolition, a new SSA must be installed. Construction Fence (CF) A construction fence restricts site access to designated entrances and exits and delineates construction site boundaries. Concrete Washout Area (CWA) The Concrete Washout Area is a sediment-trapping device as described in the UDFCD criteria. Concrete washout area(s) shall be installed prior to any concrete placement on site. All concrete delivery truck chutes, concrete pumps, and any other concrete placing devices shall be cleaned out at the designated concrete washout area. The discharge of water containing concrete waste and/or sediment to adjacent waterways, wetlands, other properties, etc. is prohibited. The contractor shall redline the approved SWMP located in the construction trailer to indicate the current location of all CWAs. Stockpile Management (SM/SP) Stockpile management includes measures to minimize erosion and sediment transport from soil stockpiles. It should be used when soils or other erodible materials are stored at the construction site. Special attention should be given to stockpiles in close proximity to natural or manmade storm systems. Updated SM/SP locations shall be redlined on the approved SWMP located in the construction trailer. This includes the location of the final SM/SP during final grading. 18 Silt Fence (SF) Silt Fence is a sediment-trapping device as described in the UDFCD criteria. Silt fence is to be inspected and repaired/replaced as necessary. Silt fence will only be used for stockpile protection for this Project because natural berms will prohibit sediment-laden runoff from exiting the site. Street Sweeping and Vacuuming (SS) Street sweeping is required when sediment has washed onto paved surfaces. This is to be done in a timely manner either by hand or street sweeper at a minimum of one time per week. Flushing of sediment with water is prohibited. Surface Roughening (SR) Any disturbed areas which have not reached final stabilization within two weeks of being disturbed shall receive surface roughening. Rock/Curb Socks (RS/CS) 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 right 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 shall be installed on the proposed 3’ concrete pan (sidewalk chase) outfalls once constructed. Inlet Protection (IP) Inlet protection shall be used at all of the locations shown on the approved SWMP plans. Inlet protection for proposed inlets should be installed immediately after proposed inlet installation. Inlet protection is to be inspected and repaired/replaced as necessary. 19 Sediment Control Log (SCL) Sediment Control Log (SCL) is a linear roll made of natural materials such as straw, coconut fiber, or other fibrous material trenched into the ground and held with a wooden stake (“straw wattles”) as described in the UDFCD criteria. SCLs shall be installed as shown on the approved SWMP plans in order to function as a check dam in the proposed grass swale. SCLs shall be installed as soon as the grass swale is graded. SCLs are to be inspected and repaired/replaced as necessary. SCL’s shall extend a minimum of 10’ total in length and shall be centered on the bottom of the grass swale. MATERIAL HANDLING AND SPILL PREVENTION If a spill should occur, the City of Fort Collins (970)-224-6015, and the Colorado Department of Public Health and Environment (877)-518-5608) must be notified. The contractor shall keep specific procedure manuals for material handling information, accident procedures, and spill handling. At a minimum, the contractor shall adhere to the following: Material and Equipment Storage: Nonhazardous materials that are to be stockpiled on the site but not installed within 14 days of arrival shall be stored in the construction staging and/or material storage area. Materials delivered to the site which will be installed within 14 days of arrival may be stored nearer to the point of installation. These materials include but are not limited to pipe, precast structures, fire hydrants, tees, valves, and misc. fittings. Construction and maintenance equipment such as hand tools and small parts shall be stored within the stabilized storage area or materials storage area in watertight containers. Hazardous materials that are to be stored on-site such as, but not limited to, oil filters, petroleum products, paint, and equipment maintenance fluids shall be stored in structurally sound and sealed containers clearly marked “Hazardous Material”. These containers are to be located within the stabilized storage areas and/or material storage area. 20 Spill Response/Management of Contaminated Soils: • Containment and cleanup of spills should begin promptly after the spill is observed • Contain medium sized spills with absorbents (e.g., kitty litter, saw dust) and use inflatable berms or absorbent snakes as temporary booms for the spill. Store and dispose of absorbents properly. • For large spills, first contain the spill and plug storm drain inlets where the liquid may migrate off-site, then clean up the spill. • Excavation of spill areas to removed contaminated material may be required where large spills occur on unpaved surfaces. • Contain the entire spill if possible. If immediate containment is not possible, use curbing to route spilled material to a collection basin. The containment area must have an impermeable surface. • Material from the spill area must be disposed of or recycled according to local, state, and federal standards. Vehicle and Equipment Fueling and Maintenance: The fueling of vehicles and equipment which occurs on site shall occur in the stabilized storage area. Only minor equipment maintenance shall occur on-site. All major equipment maintenance shall be performed off-site. Any equipment fluids generated from maintenance activities will be disposed of into designated drums stored on spill pallets. Absorbent, spill-cleanup materials and spill kits shall be available at the stabilized storage area and/or materials storage area. Drip pans shall be placed under all equipment receiving maintenance. Drip pans shall also be placed under vehicles and/or equipment parked overnight which have known fluid leaks. 21 Waste Management and Disposal, Including Concrete Washout: All hazardous waste materials shall be disposed of in structurally sound and sealed containers located within a hazardous materials storage area in the stabilized storage area. Hazardous waste materials will be stored in appropriate and clearly marked containers and segregated from other non-waste materials. Secondary containment shall be provided for all waste materials in the hazardous materials storage area and will consist of commercially available spill pallets. Additionally, all hazardous waste materials shall be disposed of in accordance with federal, state, and municipal regulations. Non- hazardous waste materials may be disposed of into on-site dumpsters. Construction trash dumpsters should be located in the stabilized storage area. Dumpsters should have a secure lid and meet all federal, state, and municipal regulations. Only trash and construction debris from the site should be deposited in these dumpster. No construction materials shall be buried on-site. All construction personnel shall be instructed regarding the correct disposal of trash and construction debris, as well as procedures for hazardous waste disposal. The SWMP Administrator shall be responsible for seeing that these practices are followed. C. SEQUENCED BMP IMPLEMENTATION GENERAL • Good Housekeeping • Material Handling and Spill Prevention INITIAL Refer to sheet C202. Prior to Asphalt Demolition, Clear and Grub • Install Existing Inlet Protection • Install Construction Fence • Install Silt Fence During and immediately following Asphalt Demolition, Clear and Grub 22 • Install VTC (VTC shall be installed as soon as possible during demolition. Limit site access until VTC is in place. Construction fence around VTC should limit access to site through the VTC only • Limit disturbance to those areas planned for disturbance and protect undisturbed areas within the site with construction fence, flagging, etc. • Sweep or Vacuum sediment as needed. Maintenance • Inspect all BMP’s after every precipitation event, and at a minimum of once per week • Replace/repair BMP’s as necessary • Check for sediment deposition on streets and sweep daily INTERIM Refer to sheet C203. Before Over-lot Grading • Install Stabilized Staging Area (Install construction trailer, stake portable toilets, and lay down dumpsters as needed) During Site Grading/Foundation Excavation • Implement stockpile management • Install Silt Fence around stockpiles • Stockpiles shall be no higher than ten feet • Water the site as needed to prevent dust from wind and loading/unloading operations. Do not water to the point that runoff is created. • Implement Surface Roughening and/or Temporary Seeding as required • Install SCL as soon as grass swale is graded During Utility installation • Install inlet protection immediately after inlets are installed During Vertical Construction • Concrete Washout Areas as needed • Implement materials management and good housekeeping practices • Use perimeter controls for temporary stockpiles from foundation excavations 23 During Paving/Concrete Installation • Concrete Washout Areas as needed for concrete paving • Install rock socks at 3’ concrete chases Maintenance • Inspect all BMP’s after every precipitation event, and at a minimum of once per week • Replace/repair BMP’s as necessary • Check for sediment deposition on streets and sweep daily • Dispose of Concrete Washout Areas in a timely fashion. • Update Erosion Control Plans to reflect current locations of major BMP’s including SSA, CWA, and SP FINAL Refer to sheet C204. • Install permanent seeding in landscaped areas shown on the plans • Do not remove BMP’s until final stabilization is achieved • In landscaped areas, individual plant density of at least 70% is required • Implement stockpile management if necessary for final grading. Redline location on approved plan in construction trailer. Maintenance • Inspect all BMP’s after every precipitation event, and at a minimum of once per week • Replace/repair BMP’s as necessary • Check for sediment deposition on streets and sweep daily • Dispose of Concrete Washout Areas in a timely fashion. 24 D. INSPECTION AND MAINTENANCE PROCEDURES The erosion and sediment control measures shall be inspected by the contractor and evaluated continually throughout the construction period. Inspections shall be performed weekly and after all storm events resulting in precipitation of one-half inch or more. Inspections shall also be required after significant snowmelt events which have the potential to cause surface erosion. Inspections required after storm and/or snowmelt events shall be conducted in a timely manner, but no more than 24 hours after the end of the storm event. If construction activities have been completed, but final stabilization has not yet been achieved, the frequency of inspections may be reduced to once every thirty (30) days. Inspections shall be conducted and findings documented pursuant to the State Permit. Inspections shall be recorded on an inspection form acceptable to both the State of Colorado and the City of Fort Collins. See the Appendix for a sample inspection form. Inspections shall ensure adherence to all state and local jurisdictional requirements. Inspections shall also ensure compliance with the erosion control measures stipulated in this report. Lost or damaged erosion and sediment control devices shall be noted in the inspection report and shall be repaired or replaced in a timely manner, but in no case more than seven (7) days after the inspection. Ineffective or inadequate devices shall also be noted in the inspection report and should be modified or replaced with an adequate device. Replacement and/or modification of ineffective or inadequate devices shall be completed in a timely manner, but in no case more than seven (7) days after the inspection. Any observed differences or modifications to the SWMP made after an inspection shall be shown on an updated SWMP in a timely manner. Any reports of non-compliance and/or violations shall be recorded. A brief explanation shall detail how the instance of non-compliance and/or violation was rectified, and how future violations will be avoided. The report shall then be signed indicating that site is 25 once again in compliance by both the individual performing the inspection and the SWMP administrator. The permit operator shall keep a record of all inspections on site with the SWMP Plan. These records shall be made available to the City of Fort Collins or other authorities having jurisdiction upon request. Wherever inspection requirements differ between governing jurisdictions and/or this SWMP, the more stringent requirements shall apply. E. FINAL STABILIZATION Final stabilization will be achieved when all disturbed areas have either been paved with asphalt/concrete or landscaped according to the project design plans. In landscaped areas, an individual plant density of at least seventy (70) percent is required for final stabilization. SOIL AMMENDMENTS Topsoil is to be stockpiled and reused. No specific soil amendments are required for the site. 26 PERMANENT SEED MIX Clayey Soils (based on 80 seeds/ft 2 and total of 15.9 lbs/PLS/acre) Drill between ¼”- ½” deep. Common Name Scientific Name Drilled lbs/PLS/acre Season Mature Height (in.) Form Sideoats Grama Bouteloua curtipendula 2.8 Warm 10-30” Bunch Buffalograss Bouteloua dactyloides 6.2 Warm 4-8” Sod Blue Grama Bouteloua gracilis 0.6 Warm 4-16” Bunch/sod Inland Saltgrass Distichlis stricta 0.9 Warm 4-16” Sod Bottlebrush squirreltail Elymus elymoides 1.8 Cool 4-20” Bunch Prairie Junegrass Koeleria macrantha 0.2 Cool 6-24” Bunch Western Wheatgrass Pascopyrum smithii 3.2 Cool 12-32” Sod Alkali Sacaton (plains- montane, wet- dry alkaline) Sporobolus airoides 0.3 Warm 20-40” Bunch • All materials furnished shall be free of Colorado State noxious weeds as defined in Article III, Section 21-40 of the Code of the City of Fort Collins. • All of the above seed mixes are based on one acre. When ordering, amounts need to be recalculated to fit actual acreage. 27 F. REFERENCES 1. Colorado Department of Public Health and Environment, Water Quality Control Division – Stormwater Program, “Stormwater Discharges Associated with Construction Activity, Stormwater Management Plan Preparation Guidance”, revised 4/2011 2. Urban Storm Drainage Criteria Manual, Volumes 1-3, Urban Drainage and Flood Control District, Rev. June 2001, Internet rev. October 2007. 3. “RE: Erosion Control Report and Drawing Requirements Accompanying Document”. Received 2/6/2012 via email from Jesse Schlam, City of Fort Collins, Utilities. JSchlam@fcgov.com miles km 1 1 ENGINEER'S OPINION OF PROBABLE COST Project: AVAGO B4 WEST ANNEX Date: 29-Apr-13 Location: 4380 ZIEGLER ROAD Job No.: 13.0091 Subject: SECURITY CALCULATIONS Prep. By: BMS Client: AVAGO TECHNOLOGIES Ckd. By: PB Note: Any opinions of price, probable project costs or construction costs rendered by MARTIN/MARTIN represent its best judgment and are furnished for general guidance. MARTIN/MARTIN makes no warranty of guarantee, either expressed or implied as to the accuracy of such opinions as compared to bid or actual cost. Item No. Item Description Units Quantity Unit Price Item Cost 1 Concrete Washout Area EA 3 $ 100.00 $ 300.00 2 Construction Fence LF 4220 $ 2.00 $ 8,440.00 3 Inlet Protection EA 25 $ 20.00 $ 500.00 4 Permanent Seeding and Mulching AC 9.5 $ 2,500.00 $ 23,750.00 5 Stabilized Staging Area SF 40000 $ 0.25 $ 10,000.00 6 VTC EA 1 $ 1,000.00 $ 1,000.00 7 Curb Sock/Rock EA 20 $ 10.00 $ 200.00 8 Sediment Control Log EA 10 $ 20.00 $ 200.00 Remarks: Cost of Items: $ 44,390.00 50% Contingencies: $ 22,195.00 $ 37,275.00 Subtotal: $ 66,585.00 14.91 ACRES @ $2,500 per ACRE Cost to revegetate is less than total BMP cost, use Total BMP Cost for required security Total Cost: $ 66,585.00 Cost to revegetate only: run date: 4/29/2013 7:06 PM Page 1 of 1 Stabilized Staging Area (SSA) SM-6 November 2010 Urban Drainage and Flood Control District SSA-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph SSA-1. Example of a staging area with a gravel surface to prevent mud tracking and reduce runoff. Photo courtesy of Douglas County. Description A stabilized staging area is a clearly designated area where construction equipment and vehicles, stockpiles, waste bins, and other construction-related materials are stored. The contractor office trailer may also be located in this area. Depending on the size of the construction site, more than one staging area may be necessary. Appropriate Uses Most construction sites will require a staging area, which should be clearly designated in SWMP drawings. The layout of the staging area may vary depending on the type of construction activity. Staging areas located in roadways due to space constraints require special measures to avoid materials being washed into storm inlets. Design and Installation Stabilized staging areas should be completed prior to other construction activities beginning on the site. Major components of a stabilized staging area include:  Appropriate space to contain storage and provide for loading/unloading operations, as well as parking if necessary.  A stabilized surface, either paved or covered, with 3-inch diameter aggregate or larger.  Perimeter controls such as silt fence, sediment control logs, or other measures.  Construction fencing to prevent unauthorized access to construction materials.  Provisions for Good Housekeeping practices related to materials storage and disposal, as described in the Good Housekeeping BMP Fact Sheet.  A stabilized construction entrance/exit, as described in the Vehicle Tracking Control BMP Fact Sheet, to accommodate traffic associated with material delivery and waste disposal vehicles. Over-sizing the stabilized staging area may result in disturbance of existing vegetation in excess of that required for the project. This increases costs, as well as requirements for long-term stabilization following the construction period. When designing the stabilized staging area, minimize the area of disturbance to the extent practical. Stabilized Staging Area Functions Erosion Control Yes Sediment Control Moderate Site/Material Yes SM-6 Stabilized Staging Area (SSA) SSA-2 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 See Detail SSA-1 for a typical stabilized staging area and SSA-2 for a stabilized staging area when materials staging in roadways is required. Maintenance and Removal Maintenance of stabilized staging areas includes maintaining a stable surface cover of gravel, repairing perimeter controls, and following good housekeeping practices. 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. Staging areas should then be permanently stabilized with vegetation or other surface cover planned for the development. Minimizing Long-Term Stabilization Requirements  Utilize off-site parking and restrict vehicle access to the site.  Use construction mats in lieu of rock when staging is provided in an area that will not be disturbed otherwise.  Consider use of a bermed contained area for materials and equipment that do not require a stabilized surface.  Consider phasing of staging areas to avoid disturbance in an area that will not be otherwise disturbed. Stabilized Staging Area (SSA) SM-6 November 2010 Urban Drainage and Flood Control District SSA-3 Urban Storm Drainage Criteria Manual Volume 3 SM-6 Stabilized Staging Area (SSA) SSA-4 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 Surface Roughening (SR) EC-1 November 2010 Urban Drainage and Flood Control District SR-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph SR-1. Surface roughening via imprinting for temporary stabilization. Description Surface roughening is an erosion control practice that involves tracking, scarifying, imprinting, or tilling a disturbed area to provide temporary stabilization of disturbed areas. Surface roughening creates variations in the soil surface that help to minimize wind and water erosion. Depending on the technique used, surface roughening may also help establish conditions favorable to establishment of vegetation. Appropriate Uses Surface roughening can be used to provide temporary stabilization of disturbed areas, such as when revegetation cannot be immediately established due to seasonal planting limitations. Surface roughening is not a stand-alone BMP, and should be used in conjunction with other erosion and sediment controls. Surface roughening is often implemented in conjunction with grading and is typically performed using heavy construction equipment to track the surface. Be aware that tracking with heavy equipment will also compact soils, which is not desirable in areas that will be revegetated. Scarifying, tilling, or ripping are better surface roughening techniques in locations where revegetation is planned. Roughening is not effective in very sandy soils and cannot be effectively performed in rocky soil. Design and Installation Typical design details for surfacing roughening on steep and mild slopes are provided in Details SR-1 and SR-2, respectively. Surface roughening should be performed either after final grading or to temporarily stabilize an area during active construction that may be inactive for a short time period. Surface roughening should create depressions 2 to 6 inches deep and approximately 6 inches apart. The surface of exposed soil can be roughened by a number of techniques and equipment. Horizontal grooves (running parallel to the contours of the land) can be made using tracks from equipment treads, stair-step grading, ripping, or tilling. Fill slopes can be constructed with a roughened surface. Cut slopes that have been smooth graded can be roughened as a subsequent operation. Roughening should follow along the contours of the slope. The tracks left by truck mounted equipment working perpendicular to the contour can leave acceptable horizontal depressions; however, the equipment will also compact the soil. Surface Roughening Functions Erosion Control Yes Sediment Control No Site/Material Management No EC-1 Surface Roughening (SR) SR-2 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Maintenance and Removal Care should be taken not to drive vehicles or equipment over areas that have been surface roughened. Tire tracks will smooth the roughened surface and may cause runoff to collect into rills and gullies. Because surface roughening is only a temporary control, additional treatments may be necessary to maintain the soil surface in a roughened condition. Areas should be inspected for signs of erosion. Surface roughening is a temporary measure, and will not provide long-term erosion control. Surface Roughening (SR) EC-1 November 2010 Urban Drainage and Flood Control District SR-3 Urban Storm Drainage Criteria Manual Volume 3 EC-1 Surface Roughening (SR) SR-4 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Temporary and Permanent Seeding (TS/PS) EC-2 November 2010 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 November 2010 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 November 2010 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 November 2010 Urban Storm Drainage Criteria Manual Volume 3 Table TS/PS-2. Minimum Drill Seeding Rates for Perennial Grasses Common a 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 November 2010 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 wheatgrass d Agropyron cristatum 'Ephriam' Cool Sod 175,000 1.5 Oahe Intermediate wheatgrass Agropyron intermedium 'Oahe' Cool Sod 115,000 5.5 Vaughn sideoats grama e 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 hay or 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 November 2010 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. Mulching (MU) EC-4 November 2010 Urban Drainage and Flood Control District MU-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph MU-1. An area that was recently seeded, mulched, and crimped. Description Mulching consists of evenly applying straw, hay, shredded wood mulch, bark or compost to disturbed soils and securing the mulch by crimping, tackifiers, netting or other measures. Mulching helps reduce erosion by protecting bare soil from rainfall impact, increasing infiltration, and reducing runoff. Although often applied in conjunction with temporary or permanent seeding, it can also be used for temporary stabilization of areas that cannot be reseeded due to seasonal constraints. Mulch can be applied either using standard mechanical dry application methods or using hydromulching equipment that hydraulically applies a slurry of water, wood fiber mulch, and often a tackifier. Appropriate Uses Use mulch in conjunction with seeding to help protect the seedbed and stabilize the soil. Mulch can also be used as a temporary cover on low to mild slopes to help temporarily stabilize disturbed areas where growing season constraints prevent effective reseeding. Disturbed areas should be properly mulched and tacked, or seeded, mulched and tacked promptly after final grade is reached (typically within no longer than 14 days) on portions of the site not otherwise permanently stabilized. Standard dry mulching is encouraged in most jurisdictions; however, hydromulching may not be allowed in certain jurisdictions or may not be allowed near waterways. Do not apply mulch during windy conditions. Design and Installation Prior to mulching, surface-roughen areas by rolling with a crimping or punching type roller or by track walking. Track walking should only be used where other methods are impractical because track walking with heavy equipment typically compacts the soil. A variety of mulches can be used effectively at construction sites, including the following types: Mulch Functions Erosion Control Yes Sediment Control Moderate Site/Material Management No EC-4 Mulching (MU) MU-2 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3  Clean, weed- and seed-free, long-stemmed grass hay (preferred) or cereal grain straw. Hay is preferred because it is less susceptible to removal by wind. Mulch should be applied evenly at a rate of 2 tons per acre and must be tacked or fastened by an approved method suitable for the type of mulch used. At least 50 percent of the grass hay mulch, by weight, should be 10 inches or more in length.  Grass hay mulch must be anchored and not merely placed on the surface. This can be accomplished mechanically by crimping or with the aid of tackifiers or nets. Anchoring with a crimping implement is preferred, and is the recommended method for areas flatter than 3:1. Mechanical crimpers must be capable of tucking the long mulch fibers into the soil to a depth of 3 inches without cutting them. An agricultural disk, while not an ideal substitute, may work if the disk blades are dull or blunted and set vertically; however, the frame may have to be weighted to afford proper soil penetration.  On small areas sheltered from the wind and heavy runoff, spraying a tackifier on the mulch is satisfactory for holding it in place. For steep slopes and special situations where greater control is needed, erosion control blankets anchored with stakes should be used instead of mulch.  Hydraulic mulching consists of wood cellulose fibers mixed with water and a tackifying agent and should be applied at a rate of no less than 1,500 pounds per acre (1,425 lbs of fibers mixed with at least 75 lbs of tackifier) with a hydraulic mulcher. For steeper slopes, up to 2000 pounds per acre may be required for effective hydroseeding. Hydromulch typically requires up to 24 hours to dry; therefore, it should not be applied immediately prior to inclement weather. Application to roads, waterways and existing vegetation should be avoided.  Erosion control mats, blankets, or nets are recommended to help stabilize steep slopes (generally 3:1 and steeper) and waterways. Depending on the product, these may be used alone or in conjunction with grass or straw mulch. Normally, use of these products will be restricted to relatively small areas. Biodegradable mats made of straw and jute, straw-coconut, coconut fiber, or excelsior can be used instead of mulch. (See the ECM/TRM BMP for more information.)  Some tackifiers or binders may be used to anchor mulch. Check with the local jurisdiction for allowed tackifiers. Manufacturer's recommendations should be followed at all times. (See the Soil Binder BMP for more information on general types of tackifiers.)  Rock can also be used as mulch. It provides protection of exposed soils to wind and water erosion and allows infiltration of precipitation. An aggregate base course can be spread on disturbed areas for temporary or permanent stabilization. The rock mulch layer should be thick enough to provide full coverage of exposed soil on the area it is applied. Maintenance and Removal After mulching, the bare ground surface should not be more than 10 percent exposed. Reapply mulch, as needed, to cover bare areas. Concrete Washout Area (CWA) MM-1 November 2010 Urban Drainage and Flood Control District CWA-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph CWA-1. Example of concrete washout area. Note gravel tracking pad for access and sign. Description Concrete waste management involves designating and properly managing a specific area of the construction site as a concrete washout area. A concrete washout area can be created using one of several approaches 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. Three basic approaches are available: excavation of a pit in the ground, use of an above ground storage area, or use of prefabricated haul- away concrete washout containers. Surface discharges of concrete washout water from construction sites are prohibited. Appropriate Uses 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. Because pH is a pollutant of concern for washout activities, when unlined pits are used for concrete washout, the soil must have adequate buffering capacity to result in protection of state groundwater standards; otherwise, a liner/containment must be used. The following management practices are recommended to prevent an impact from unlined pits to groundwater:  The use of the washout site should be temporary (less than 1 year), and  The washout site should be not be located in an area where shallow groundwater may be present, such as near natural drainages, springs, or wetlands. Design and Installation 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. Although unlined washout areas may be used, lined pits may be required to protect groundwater under certain conditions. Do not locate an unlined washout area within 400 feet of any natural drainage pathway or waterbody or within 1,000 feet of any wells or drinking water sources. Even for lined concrete washouts, it is advisable to locate the facility away from waterbodies and drainage paths. If site constraints make these Concrete Washout Area Functions Erosion Control No Sediment Control No Site/Material Management Yes MM-1 Concrete Washout Area (CWA) CWA-2 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 setbacks infeasible or if highly permeable soils exist in the area, then the pit must be installed with an impermeable liner (16 mil minimum thickness) or surface storage alternatives using prefabricated concrete washout devices or a lined aboveground storage area should be used. Design details with notes are provided in Detail CWA-1 for pits and CWA-2 for aboveground storage areas. Pre-fabricated concrete washout container information can be obtained from vendors. Maintenance and Removal A key consideration for concrete washout areas is to ensure that adequate signage is in place identifying the location of the washout area. Part of inspecting and maintaining washout areas is ensuring that adequate signage is provided and in good repair and that the washout area is being used, as opposed to washout in non-designated areas of the site. Remove concrete waste in the washout area, as needed to maintain BMP function (typically when filled to about two-thirds of its capacity). Collect concrete waste and deliver offsite to a designated disposal location. Upon termination of use of the washout site, accumulated solid waste, including concrete waste and any contaminated soils, must be removed from the site to prevent on-site disposal of solid waste. If the wash water is allowed to evaporate and the concrete hardens, it may be recycled. Photograph CWA-3. Earthen concrete washout. Photo courtesy of CDOT. Photograph CWA-2. Prefabricated concrete washout. Photo courtesy of CDOT. Concrete Washout Area (CWA) MM-1 November 2010 Urban Drainage and Flood Control District CWA-3 Urban Storm Drainage Criteria Manual Volume 3 MM-1 Concrete Washout Area (CWA) CWA-4 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Stockpile Management (SP) MM-2 November 2010 Urban Drainage and Flood Control District SP-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph SP-1. A topsoil stockpile that has been partially revegetated and is protected by silt fence perimeter control. Description Stockpile management includes measures to minimize erosion and sediment transport from soil stockpiles. Appropriate Uses Stockpile management should be used when soils or other erodible materials are stored at the construction site. Special attention should be given to stockpiles in close proximity to natural or manmade storm systems. Design and Installation Locate stockpiles away from all drainage system components including storm sewer inlets. Where practical, choose stockpile locations that that will remain undisturbed for the longest period of time as the phases of construction progress. Place sediment control BMPs around the perimeter of the stockpile, such as sediment control logs, rock socks, silt fence, straw bales and sand bags. See Detail SP-1 for guidance on proper establishment of perimeter controls around a stockpile. For stockpiles in active use, provide a stabilized designated access point on the upgradient side of the stockpile. Stabilize the stockpile surface with surface roughening, temporary seeding and mulching, erosion control blankets, or soil binders. Soils stockpiled for an extended period (typically for more than 60 days) should be seeded and mulched with a temporary grass cover once the stockpile is placed (typically within 14 days). Use of mulch only or a soil binder is acceptable if the stockpile will be in place for a more limited time period (typically 30-60 days). Timeframes for stabilization of stockpiles noted in this fact sheet are "typical" guidelines. Check permit requirements for specific federal, state, and/or local requirements that may be more prescriptive. Stockpiles should not be placed in streets or paved areas unless no other practical alternative exists. See the Stabilized Staging Area Fact Sheet for guidance when staging in roadways is unavoidable due to space or right-of-way constraints. For paved areas, rock socks must be used for perimeter control and all inlets with the potential to receive sediment from the stockpile (even from vehicle tracking) must be protected. Maintenance and Removal Inspect perimeter controls and inlet protection in accordance with their respective BMP Fact Sheets. Where seeding, mulch and/or soil binders are used, reseeding or reapplication of soil binder may be necessary. When temporary removal of a perimeter BMP is necessary to access a stockpile, ensure BMPs are reinstalled in accordance with their respective design detail section. Stockpile Management Functions Erosion Control Yes Sediment Control Yes Site/Material Management Yes MM-2 Stockpile Management (SM) SP-2 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 When the stockpile is no longer needed, properly dispose of excess materials and revegetate or otherwise stabilize the ground surface where the stockpile was located. Stockpile Management (SP) MM-2 November 2010 Urban Drainage and Flood Control District SP-3 Urban Storm Drainage Criteria Manual Volume 3 MM-2 Stockpile Management (SM) SP-4 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Stockpile Management (SP) MM-2 November 2010 Urban Drainage and Flood Control District SP-5 Urban Storm Drainage Criteria Manual Volume 3 MM-2 Stockpile Management (SM) SP-6 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 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 Sediment Control Log (SCL) SC-2 November 2010 Urban Drainage and Flood Control District SCL-1 Urban Storm Drainage Criteria Manual Volume 3 Photographs SCL-1 and SCL-2. Sediment control logs used as 1) a perimeter control around a soil stockpile; and, 2) as a "J-hook" perimeter control at the corner of a construction site. Description A sediment control log is a linear roll made of natural materials such as straw, coconut fiber, or other fibrous material trenched into the ground and held with a wooden stake. Sediment control logs are also often referred to as "straw wattles." They are used as a sediment barrier to intercept sheet flow runoff from disturbed areas. Appropriate Uses Sediment control logs can be used in the following applications to trap sediment:  As perimeter control for stockpiles and the site.  As part of inlet protection designs.  As check dams in small drainage ditches. (Sediment control logs are not intended for use in channels with high flow velocities.)  On disturbed slopes to shorten flow lengths (as an erosion control).  As part of multi-layered perimeter control along a receiving water such as a stream, pond or wetland. Sediment control logs work well in combination with other layers of erosion and sediment controls. Design and Installation Sediment control logs should be installed along the contour to avoid concentrating flows. The maximum allowable tributary drainage area per 100 lineal feet of sediment control log, 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 sediment control logs installed along the contour. When installed for other uses, such as perimeter control, it 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 BMP. Sediment Control Log Functions Erosion Control Moderate Sediment Control Yes Site/Material Management No SC-2 Sediment Control Log (SCL) SCL-2 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Although sediment control logs initially allow runoff to flow through the BMP, they can quickly become a barrier and should be installed is if they are impermeable. Design details and notes for sediment control logs are provided in Detail SCL-1. Sediment logs must be properly trenched and staked into the ground to prevent undercutting, bypassing and displacement. When installed on slopes, sediment control logs should be installed along the contours (i.e., perpendicular to flow). Improper installation can lead to poor performance. Be sure that sediment control logs are properly trenched, anchored and tightly jointed. Maintenance and Removal Be aware that sediment control logs will eventually degrade. Remove accumulated sediment before the depth is one-half the height of the sediment log and repair damage to the sediment log, typically by replacing the damaged section. Once the upstream area is stabilized, remove and properly dispose of the logs. Areas disturbed beneath the logs may need to be seeded and mulched. Sediment control logs that are biodegradable may occasionally be left in place (e.g., when logs are used in conjunction with erosion control blankets as permanent slope breaks). However, removal of sediment control logs after final stabilization is typically recommended when used in perimeter control, inlet protection and check dam applications. Sediment Control Log (SCL) SC-2 November 2010 Urban Drainage and Flood Control District SCL-3 Urban Storm Drainage Criteria Manual Volume 3 SC-2 Sediment Control Log (SCL) SCL-4 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Sediment Control Log (SCL) SC-2 November 2010 Urban Drainage and Flood Control District SCL-5 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 November 2010 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 Design and Installation a stand-alone BMP and should be used in conjunction with other upgradient BMPs. 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 November 2010 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 November 2010 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 November 2010 Urban Storm Drainage Criteria Manual Volume 3 Inlet Protection (IP) SC-6 November 2010 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 November 2010 Urban Storm Drainage Criteria Manual Volume 3 Inlet Protection (IP) SC-6 November 2010 Urban Drainage and Flood Control District IP-7 Urban Storm Drainage Criteria Manual Volume 3 Construction Fence (CF) SM-3 November 2010 Urban Drainage and Flood Control District CF-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph CF-1. A construction fence helps delineate areas where existing vegetation is being protected. Photo courtesy of Douglas County. Description A construction fence restricts site access to designated entrances and exits, delineates construction site boundaries, and keeps construction out of sensitive areas such as natural areas to be preserved as open space, wetlands and riparian areas. Appropriate Uses A construction fence can be used to delineate the site perimeter and locations within the site where access is restricted to protect natural resources such as wetlands, waterbodies, trees, and other natural areas of the site that should not be disturbed. If natural resource protection is an objective, then the construction fencing should be used in combination with other perimeter control BMPs such as silt fence, sediment control logs or similar measures. Design and Installation Construction fencing may be chain link or plastic mesh and should be installed following manufacturer’s recommendations. See Detail CF-1 for typical installations. Do not place construction fencing in areas within work limits of machinery. Maintenance and Removal  Inspect fences for damage; repair or replace as necessary.  Fencing should be tight and any areas with slumping or fallen posts should be reinstalled.  Fencing should be removed once construction is complete. Construction Fence Functions Erosion Control No Sediment Control No Site/Material Management Yes SM-3 Construction Fence (CF) CF-2 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Construction Fence (CF) SM-3 November 2010 Urban Drainage and Flood Control District CF-3 Urban Storm Drainage Criteria Manual Volume 3 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