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HomeMy WebLinkAboutTHE DISTRICT AT CAMPUS WEST - FDP - FDP120021 - SUBMITTAL DOCUMENTS - ROUND 1 - DRAINAGE REPORT (3)STORMWATER MANAGEMENT PLAN (SWMP) / EROSION CONTROL REPORT THE DISTRICT AT CAMPUS WEST Fort Collins, Colorado December 5, 2012 Prepared for: Ft. Collins Student Housing, LLC 1302 Waugh Drive, PMB 305 Houston, TX 77019 Prepared by: 200 South College Avenue, Suite 10 Fort Collins, Colorado 80524 Phone: 970.221.4158 Fax: 970.221.4159 www.northernengineering.com Project Number: 670-001 3 This Report is consciously provided as a PDF. Please consider the environment before printing this document in its entirety. When a hard copy is absolutely necessary, we recommend double-sided printing. December 5, 2012 City of Fort Collins Stormwater Utility 700 Wood Street Fort Collins, CO 80521 RE: Stormwater Management Plan/Erosion Control Report The District at Campus West Dear Staff: Northern Engineering Services, Inc. is pleased to submit this Stormwater Management Plan and Erosion Control Report for The District at Campus West. This report outlines Best Management Practices (BMPs) to be implemented with the proposed construction in order to minimize potential pollutants in stormwater discharges. We have prepared this report to accompany the Colorado Department of Public Health and Environment (CDPHE) General Permit for Stormwater Discharge Associated with Construction Activities (aka, Stormwater Discharge Permit or SDP). The General Permit No. for this SDP is COR-XXXXXXXXXX and the Certification No. for this SDP is CORXXXXX. The Permit Certification is effective beginning Month Day, Year, and initial certification expires Month Day, Year. A copy of the issuance cover letter can be found in the Appendix D of this document. Please note: this Stormwater Management Plan (including the Site Maps) is not a static document, it is a dynamic device that should be kept current and logged as construction takes place. As such, this version was prepared to facilitate initial plan approvals and permitting, but does not necessarily reflect the final version, or the transitions throughout the construction process. As the site develops and changes, the contractor is expected and encouraged to make changes to what is contained herein so that the Stormwater Management Plan (SWMP) works as effectively and efficiently as possible. It shall be the responsibility of the SWMP Administrator and/or the permit holder (or applicant thereof) to ensure the plan is properly maintained and followed. If you should have any questions or comments as you review this report, please feel free to contact us at your convenience. Sincerely, NORTHERN ENGINEERING SERVICES, INC. Herman Feissner, P.E. Project Engineer The District at Campus West Stormwater Management Plan TABLE OF CONTENTS Vicinity Map 1.0 General Requirements..............................................................................................1 1.1 Objectives...............................................................................................................1 1.2 SWMP Availability ...................................................................................................1 1.3 Definitions ..............................................................................................................1 1.4 Additional Permitting ................................................................................................1 2.0 Narrative Site Description .........................................................................................2 2.1 Existing Site Description ............................................................................................2 2.2 Wind and Rainfall Erodibility | Sediment Migration Patterns ...........................................2 2.3 Nature of Construction Activity ...................................................................................2 2.4 Sequence of Major Activities ......................................................................................2 2.5 Site Disturbance ......................................................................................................2 2.6 Existing Data...........................................................................................................3 2.7 Existing Vegetation ...................................................................................................3 2.8 Potential Pollution Sources ........................................................................................3 2.9 Non-stormwater discharges .......................................................................................3 2.10 Receiving Waters .....................................................................................................4 3.0 Stormwater Management Controls .............................................................................5 3.1 SWMP Administrator ................................................................................................5 3.2 Best Management Practices (BMPs) for Stormwater Pollution Prevention ..........................5 3.3 Structural Practices for Erosion and Sediment Control ....................................................5 3.4 Non-Structural Practices for Erosion and Sediment Control .............................................7 3.5 Phased BMP Installation ...........................................................................................9 3.6 Material Handling and Spill Prevention ........................................................................9 3.7 Vehicle Tracking Control ......................................................................................... 10 3.8 Waste Management and Disposal ............................................................................. 10 3.9 Groundwater and Stormwater Dewatering .................................................................. 11 4.0 Final Stabilization and Long-Term Stormwater Management ....................................... 12 4.1 Final Stabilization .................................................................................................. 12 4.2 Long-Term Stormwater Management ......................................................................... 12 5.0 Inspection, Maintenance and Record Keeping ........................................................... 13 5.1 BMP Inspection ..................................................................................................... 13 5.2 BMP Maintenance ................................................................................................. 13 5.3 Record Keeping ..................................................................................................... 13 6.0 Additional SWMP and BMP Resources ..................................................................... 15 References 16 The District at Campus West Stormwater Management Plan APPENDICES: APPENDIX A – Site Maps APPENDIX B – Erosion Control Details APPENDIX C – Landscape Plan (with future submittal) APPENDIX D – Copies of Permits/Applications (with future submittal) APPENDIX E – Stormwater Management Plan Inspection Log (with future submittal) APPENDIX F – Contractor Inserts (as needed) APPENDIX G – Contractor Inserts (as needed) The District at Campus West Stormwater Management Plan 1 1.0 General Requirements 1.1 Objectives The objective of a Stormwater Management Plan (SWMP) is to identify all potential sources of pollution likely to occur as a result of construction activity associated with the site construction, and describe the practices that will be used to reduce the pollutants in stormwater discharges from the site. The SWMP must be completed and implemented at the time the project breaks ground, and revised as necessary as construction proceeds to accurately reflect the conditions and practices at the site. This report summarizes the Stormwater Management Plan for the construction activity that will occur with The District at Campus West (project site). This plan has been prepared according to regulations of the Colorado Department of Public Health and Environment (CDPHE), Water Quality Control Division. 1.2 SWMP Availability This report is intended to remain at the construction site to allow for maintenance and inspection updates and for review during inspection. 1.3 Definitions Best Management Practices (BMPs) – BMPs encompass a wide range of erosion and sediment control practices, both structural and non-structural in nature, which are intended to reduce or eliminate potential water quality impacts from construction site stormwater runoff. Erosion Control BMPs – These practices are intended to prevent the erosion of soil. A few common examples include: minimizing the amount of disturbed area through phasing, temporary stabilization and preserving existing vegetation. Sediment Control BMPs – These practices are designed to remove sediment from runoff. Examples of a few include: straw wattles, silt fence and inlet protection. Non-structural BMPs – These BMPs prevent or limit the entry of pollutants into stormwater at their source through operational or managerial techniques. Some examples include: the preservation of natural vegetation, preventive maintenance and spill response procedures. Structural BMPs – Structural practices are designed to control on-site erosion and prevent sediment from migrating within the project site as well as off-site during construction. This type of BMP includes physical processes ranging from diversion structures to inlet protection and silt fence. 1.4 Additional Permitting As mentioned above, this Stormwater Management Plan is associated with the Colorado Department of Public Health and Environment (CDPHE) Stormwater Permit that is issued by the Water Quality Control Division of the CDPHE. Additional environmental permitting not described in this report will likely be required as a part of this project. An example is the Construction Dewatering Permit for groundwater, which will be discussed later. Another example is the Air Pollution Emission Notice (APEN). The CDPHE website contains links to both of these permits, as well as many other potential permits. The contractor is responsible for ensuring the proper permits are acquired. The District at Campus West Stormwater Management Plan 2 2.0 Narrative Site Description 2.1 Existing Site Description The project site is located in the Northeast Quarter of Section 15, Township 7 North, Range 69 West of the 6th Principal Meridian, City of Fort Collins, County of Larimer, State of Colorado. The District at Campus West is located on the north side of West Plum Street, and is bordered by City Park Avenue on the west and Aster Street on the east. Bluebell Street runs continuously north-south through the eastern third of the site, and will remain a through public street. However, two existing dead-end streets (Columbine Street and Daisy Street) will be vacated as part of this redevelopment. 2.2 Wind and Rainfall Erodibility | Sediment Migration Patterns The site is located within a Moderate Risk Wind Erodibility Zone per the City of Fort Collins Wind Erodibility Map. According to the Natural Resources Conservation Service website - www.websoilsurvey.nrcs.usda.gov, the applicable soil erodibility factor (K) is 0.20. This value is indicative of soils moderately susceptible to rainfall erosion. The long-term likelihood of erosion and sediment problems occurring on-site is minimal because impervious area will permanently stabilize the areas disturbed by proposed construction activity. During the interim period, in which the disturbed areas are open, the BMPs described herein were selected to prevent erosion and limit sediment migration. 2.3 Nature of Construction Activity The proposed District at Campus West project will completely raze all of the existing structures currently occupying the property. Both Daisy and Columbine Streets are proposed to be vacated and redeveloped as part of this project. The completed project will contain approximately 192 multi- family dwelling units in three main buildings. Other improvements include: a parking structure, secured bike storage, maintenance facilities, plazas, a clubhouse and an outdoor pool and courtyard area. Infrastructure to support the expansions is also proposed with the project. 2.4 Sequence of Major Activities To complete the project, many basic construction activities will take place. The project will begin by stripping the site of topsoil or by removing existing site improvements, followed by site grading where needed. The installation of utilities will occur next and includes: domestic water, sanitary sewer, storm sewer and underdrain system. Once the site grading and utility installation is complete it is anticipated that construction of the building foundations will begin. While building foundations are being constructed, concrete barrier curbs will be installed throughout the project. Vertical construction of the buildings is expected to commence once the public infrastructure has been inspected by the City of Fort Collins (City). Permeable paver installation and fine grading of the areas around the buildings as well as landscaping throughout the project will mark the completion of construction activities on the site. 2.5 Site Disturbance The project site is approximately 3.34 net acres. Site disturbance is expected to be uniform. West Plum Street, from Aster Street to City Park Avenue will be milled and overlaid. The District at Campus West Stormwater Management Plan 3 2.6 Existing Data In order to complete the associated construction plans, a series of topographical surveys of the site were completed. These surveys consisted of field measurements made by Northern Engineering Services, Inc. beginning in August 2011, with additional information gathered in May 2012. In addition to the field survey, the Natural Resources Conservation Service (NRCS) Web Soil Survey (WSS) was used to determine existing soil types found on-site. According to the NRCS WSS, the site consists primarily of Nunn Clay Loam, 1 to 3 percent slopes. The Nunn Clay Loam is classified as Hydrologic Soil Group C. More site-specific exploration was performed by Terracon Consultants, Inc. Detailed results from the site investigation is contained in the Geotechnical Engineering Report The District at CSU East of West Plum Street and City Park Avenue Fort Collins, Colorado (Terracon project No. 20115026) dated November 2, 2011. 2.7 Existing Vegetation The existing ground cover consists of concrete, asphalt, grass, gravel, areas of bare soil (e.g., unkept lawns and former grassed areas now used for parking cars), shrubs, bushes and mature trees. Being already developed lots, the slopes are rather gentle throughout (i.e., 2±%). General topography slopes from north to the south towards West Plum Street, which slopes west to east. In general, the existing vegetative cover is consistent with the age and upkeep of single-family student housing. Ground surfaces are stabilized (i.e., >70% ground cover) - thus minimum ground erosion. 2.8 Potential Pollution Sources As is typical with most construction sites, there are a number of potential pollution sources which could affect water quality. It is not possible for this report to identify all materials that will be used or stored on the construction site. It is the sole responsibility of the contractor to identify and properly handle all materials that are potential pollution sources. The following are some common examples of potential pollution sources: x Exposed and stored soils x Management of contaminated soils x Off-site tracking of soils and sediment x Loading and unloading operations x Outdoor storage of building materials, fertilizers, chemicals, etc. x Vehicle and equipment maintenance and fueling x Significant dust or particulate generating processes x Routine maintenance activities involving fertilizers, pesticides, detergents, fuels, solvents, oils, etc. x On-site waste disposal practices (e.g., waste piles, dumpsters, etc.) x Concrete truck/equipment washing x Non-industrial waste sources that may be significant (e.g., worker trash and portable toilets) x Uncovered trash bins x Other areas or procedures where potential spills can occur x Stockpiling of materials that can be transported to receiving waterway(s) 2.9 Non-stormwater discharges The construction permits issued under the CDPS General Permit for stormwater discharges associated with construction activities only covers discharges composed entirely of stormwater. Exceptions include emergency fire fighting activities, landscape irrigation return flow, uncontaminated springs, construction dewatering (caused by storm events) and concrete washout water. Proper treatment and use of BMPs is still required for these exceptions when available. The District at Campus West Stormwater Management Plan 4 The discharge of pumped stormwater, ONLY, from excavations, ponds, depressions, etc. to surface waters, or to a municipal storm sewer system is allowed by the Stormwater Construction Permit, as long as the dewatering activity and associated BMPs are identified in the SWMP are implemented in accordance with the SWMP. Aside from the exceptions noted above, non-stormwater discharges must be addressed in a separate permit issued for that discharge. If groundwater is encountered, and dewatering is required, a Construction Dewatering Permit must be acquired from the Colorado Department of Public Health and Environment. 2.10 Receiving Waters Stormwater runoff from the project area will generally sheet flow into a system of roof drains and swales that are connected to four independent permeable paver sections or the stormwater detention vault in Building 2. These systems release into the proposed storm drain system in West Plum Street. The proposed drainage patterns are generally consistent with historic drainage patterns. The District at Campus West Stormwater Management Plan 5 3.0 Stormwater Management Controls 3.1 SWMP Administrator A SWMP Administrator must be designated in conjunction with the Stormwater Permit. This person shall be responsible for developing, implementing, maintaining and revising the SWMP. The SWMP Administrator will also be the contact for all SWMP-related issues and will be the person responsible for the accuracy, completeness and implementation of the SWMP. The Administrator should be a person with authority to adequately manage and direct day-to-day stormwater quality management activities at the site. The SWMP Administrator for this site is: Name: Company: Phone: E-mail: 3.2 Best Management Practices (BMPs) for Stormwater Pollution Prevention Best Management Practices (BMPs) are loosely defined as a method, activity, maintenance procedure or other management practice for reducing the amount of pollution entering a water body. The term originated from rules and regulations in Section 208 of the Clean Water Act. Beginning with mobilization, and throughout the entire construction of the buildings, erosion control devices shall be installed and maintained to minimize pollutant migration. The BMPs may be installed or implemented in phases, or not at all, depending on actual conditions encountered at the site. It is the responsibility of the contractor to make the determination as to what practices should be employed and when. In the event that a review agency deems BMPs to be insufficient, it shall be the responsibility of the contractor to implement modifications as directed. The Drainage and Erosion Control Plans (Refer to sheet C600 and C601 in Appendix A) illustrates the assumed location for each of the BMPs. Details for recommended BMPs are included in Appendix A. These details should be used for additional information on installation and maintenance of BMPs described herein. Details for Structural and Non-Structural BMPs have been included in Appendix B. These details should be used for additional information on installation and maintenance of BMPs specified in this report. It is also intended to serve as a resource for additional BMPs that may be appropriate for the site that have not specifically been mentioned in the report. 3.3 Structural Practices for Erosion and Sediment Control Structural BMPs are physical devices that prevent or minimize water quality impacts associated with construction site stormwater runoff. These devices can be temporary or permanent, and the installation of individual components will vary depending on the stage of construction. A table depicting the construction sequence and BMP application/removal will be placed on the “Dynamic Site Plan” (with future submittal) to help document the implementation of these BMPs. Refer to the Drainage and Erosion Control Plan in the Appendix A for the assumed location of all BMPs. Construction Details for Temporary BMPs are located in Appendix A for reference. Again, the final determination of which BMPs will be installed, where they will be located and when they will be installed shall be made by the contractor, along with all documentation throughout the construction process. The District at Campus West Stormwater Management Plan 6 Silt Fencing Silt fencing shall be provided to prevent migration of sediment off-site into the public right- of-way or onto adjacent properties. All silt fencing shall be installed prior to any land disturbing activity (i.e., stockpiling, stripping, grading, excavation, earthwork activities, etc.). The silt fence inspections should identify tears or holes in the material as well as check for slumping fence or undercut areas that allow flows to bypass the fencing. The damaged sections of fencing should be repaired or replaced. Sediment accumulations equal to or greater than 6 inches behind the silt fence should be removed to maintain BMP effectiveness. At a minimum, it is suggested that silt fencing shall be located along the northern boundary of the disturbed area to prevent sediment from leaving the site and entering the neighboring. Sediment Control Log – aka “Straw Wattles” 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 anchored with a wooden stake. Sediment Control Logs can be used as perimeter control for stockpiles, as part of inlet protection designs, as check dams in small drainage ways (e.g., swales) or on disturbed slopes to shorten flow lengths. Sediment Control Logs should be inspected for excess sediment accumulation. The sediment should be removed prior to reaching half the height of the log. At a minimum, Sediment Control Logs should be used around soil stockpiles and for inlet protection in unpaved areas of the site. Vehicle Tracking Control Pads Vehicle tracking control pads shall be provided to minimize tracking of mud and sediment onto paved surfaces and neighboring roadways. All vehicle tracking control pads shall be installed prior to any land disturbing activity (e.g., stockpiling, stripping, grading, etc.). The vehicle tracking control pads should be located at any and all existing and future vehicle accesses being used during any of the construction phases. These locations will primarily be dictated by gates or openings in the temporary construction fencing. Vehicle tracking pads should be inspected for degradation. The aggregate material should remain rough and be replaced if the area becomes clogged with water and/or excess sediment. Suggested locations for vehicle tracking pads are at the north and south ends of Bluebell Street. Curb Inlet Protection Curb inlet protection shall be provided for the existing and proposed curb inlets to prevent sediment transport from adjacent earthwork disturbance. The filters should be installed before adjacent earthmoving activities. Wattle type filters are to be implemented for new and existing inlets where asphalt is not yet installed. For these inlets, if pavement is constructed adjacent to the structure or if the area adjacent to the inlet is changed such that the wattle type filter is no longer effective, it shall be the responsibility of the contractor to ensure that an appropriate method is used instead. For example, the wattle filter could be reused, or a gravel-block inlet filter may be installed. Inlet protection should be inspected regularly for tears that can result in sediment entering The District at Campus West Stormwater Management Plan 7 an inlet. Inlet protection should also be inspected for sediment accumulation upstream of the inlet. Existing inlets that will likely need protection are located at Bluebell and West Plum Streets and Aster and Wet Plum Streets. When the existing inlet at the corner of Bluebell and West Plum Streets is removed, the inlet protection will also need to be removed and replaced at inlet's new location . Check Dams After swales and drainage ways have been graded, check dams shall be installed per standard details and requirements. Check dam heights should allow for pools to develop upstream of each check dam, creating minor backwaters to both prevent scour velocities and to allow sediment deposition in the swale. The check dams should be spaced so that the top of each dam is equal in elevation to the toe of the next upstream check dam. Installation should occur within a reasonable timeframe from the completion of swale grading/construction. Check dams should be inspected regularly for gaps or holes which would allow water to pass through the structures untreated. The accumulated sediment should be removed and typically prior to the sediment depth reaching half the height of the check dam. At a minimum, check dams shall be installed at 50 foot intervals within the swale located north of Building 2. Concrete Washout Area A concrete washout should be provided on the site. The washout can be a lined or unlined excavated pit in the ground, a commercially manufactured prefabricated container or an aboveground holding area. The concrete washout must be located a minimum of 400 feet from any natural drainage way or body of water and at least 1000 feet from any wells or drinking water sources. Washout areas should not be located in an area where shallow groundwater may be present. The contractor shall clearly show the desired location and access to the Concrete Washout Area on the Stormwater Management Plan - Dynamic Site Plan. The contractor shall place a Vehicle Tracking Pad if the selected location for the Concrete Washout Area is detached from pavement. Clear signage identifying the concrete washout should also be provided. The Concrete Washout Area should be inspected regularly with particular attention being paid to signage to ensure that the area is clearly marked. Confirmation that the washout is being used should also be noted to ensure that other undesignated areas of the site are not being used incorrectly as a concrete washout. 3.4 Non-Structural Practices for Erosion and Sediment Control Non-Structural BMPs are practices or activities that are implemented to prevent erosion from happening or to limit erosion once it occurs. These BMPs can be a practice resulting in a physical change to the site, such as mulching or slope stabilization. They can also result in behavioral changes on the site, such as changes to construction phasing to minimize exposure to weather elements or increased employee awareness gained through training. Protection of Existing Vegetation Protection of existing vegetation on a construction site can be accomplished through installation of a construction fence around the area requiring protection. In cases where upgradient areas are disturbed, it may also be necessary to install perimeter controls to The District at Campus West Stormwater Management Plan 8 minimize sediment loading to sensitive areas such as wetlands. Trees that are to remain after construction is complete must also be protected. Most tree roots grow within the top 12”-18” of soil, and soil compaction is a significant threat to tree health. As such, particular care should be taken to avoid activities within the drip-line of the tree. Direct equipment damage should also be prevented. The most effective way to ensure the health of trees is to establish a protection zone at the drip-line of the tree. Fencing should be inspected and repaired as needed. If damage occurs to a tree, an arborist should be consulted. If a tree is damage beyond repair, the City Forester should be consulted on remediation measures. Stockpile Management Stockpile management should be utilized to minimize erosion and sediment transport from soil stockpiles. In general, soil stockpiles should be located a minimum of 100 feet from any drainage way and 50 feet from any storm sewer inlets. Where practical, choose a stockpile location that will remain undisturbed for the longest period of time as the phases of construction progress. Sediment control BMPs should be placed around the perimeter of the stockpile, and a designated access point on the upstream side of the stockpile should be identified. BMPs such as surface roughening, temporary seeding, mulching, erosion control blankets or soil binders should be used to stabilize the stockpile surface. As a part of stockpile management, regular inspections of the perimeter controls should be completed. If BMPs have been utilized to stabilize the surface of the stockpile, they should be inspected and repaired as needed. Mulching 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. The most common type of mulch used is hay or grass that is crimped into the soil to keep it secure. The Contractor shall mulch all planted areas within twenty-four (24) hours after planting. Only weed-free and seed-free straw mulch may be used. Straw mulch should be applied at two (2) tons per acre, and shall be adequately secured by crimping, tackifier, netting or blankets. Hydraulic mulching may also be used on steep slopes or where access is limited. In the case that hydraulic mulching is utilized, the contractor shall use wood cellulose fibers mixed with water at two thousand to two thousand five hundred (2,000-2,500) pounds per acre and organic tackifier at one hundred to four hundred (100-400) pounds per acre. Wind Erosion/Dust Control Wind Erosion and Dust Control BMPs help to keep soil particles from entering the air as a result of land disturbing construction activities. Examples include the use of a water truck or irrigation/sprinkler system to wet the top layer of disturbed soil, seeding and mulching, soil binders or wind fences. If a water truck or irrigation/sprinkler system is utilized, then monitoring for sufficient water application is crucial to ensuring soil particles don’t become airborne. Equally important is monitoring for overwatering, as too much water can lead to increased erosion and sediment laden construction site runoff. The District at Campus West Stormwater Management Plan 9 Good Housekeeping Practices Good housekeeping practices that will prevent pollution associated with solid, liquid and hazardous construction-related materials and wastes should be implemented throughout the project. Examples of good housekeeping include providing an appropriate location for waste management containers, establishing proper building material staging areas, designating paint and concrete washout areas and establishing proper equipment/vehicle fueling and maintenance practices. Development of a spill prevention and response plan is another example of Good Housekeeping practices that should be used on the project. Street Sweeping and Vacuuming – Street sweeping and vacuuming should be used to remove sediment that has been tracked onto adjacent roadways. Roadways should be inspected at least once a day, and sediment should be removed as needed. A check of inlet protection should be completed after sweeping to ensure nothing was displaced during sweeping operations. Waste Management – Designate trash and bulk waste collection areas on-site. When possible, materials should be recycled. Hazardous material waste should be segregated from other solid waste. Waste collection areas should be located away from streets, gutters, watercourses and storm drains. Dumpsters should be located near site entrances to minimize traffic on disturbed soils, and they should be placed on a level soil surface. Establish Proper Building Material Handling and Staging areas – Clearly designate site areas for staging and storage of building materials. Provide appropriate BMPs to ensure that spills or leaks are contained. Establish Proper Equipment/Vehicle Fueling and Maintenance Practices – If needed, create a clearly designated on-site fueling and maintenance area that is clean and dry. Provide appropriate BMPs to ensure that spills or leaks are contained. 3.5 Phased BMP Installation It is important to recognize the four (4) major Development Phases as defined by the State of Colorado’s Stormwater Discharge Permit (SDP). These four development phases (referred to as Sequencing by the City of Fort Collins) have been distinguished to aid in the appropriate timing of installation/implementation of BMPs at different stages of the construction process. These phases are described as follows: Phase I – Grading Stage; BMPs for initial installation of perimeter controls Phase II – Infrastructure Stage; BMPs for utility, paving and curb installation Phase III – Vertical Construction Stage; BMPs for individual building construction. Phase IV – Permanent BMPs and final site stabilization. 3.6 Material Handling and Spill Prevention Potential pollution sources, as discussed in earlier sections, are to be to be identified by the contractor. Spill prevention procedures are to be determined and put in place prior to construction by the contractor. A spill and flooding response procedure must also be determined and put in place prior to construction by the contractor. Additionally, steps should be taken to reduce the potential for leaks and spills coming into contact with stormwater runoff. The District at Campus West Stormwater Management Plan 10 A notification procedure must be put in place by the contractor, by which workers would first notify the site construction superintendent, who would then notify the SWMP Administrator. Depending on the severity of the spill, the site construction superintendent and SWMP Administrator would possibly notify the Colorado Department of Public Health and Environment - Water Quality Control Division, downstream water users or other appropriate agencies. The release of any chemical, oil, petroleum product, sewage, etc., which enter waters of the State of Colorado (which include surface water, ground water, and dry gullies or storm sewers leading to surface water) must be reported immediately to the Division’s emergency spill reporting line at (877) 518-5608. All spills that will require cleanup, even if the spill is minor and does not need to be reported to the state, should still be reported to the City Utilities office at 970-221-6700. While not expected with this project, it will be the responsibility of the contractor to designate a fueling area and take the necessary precautions to ensure that no stormwater pollution occurs in the event that a fueling area is needed. Fueling areas shall be located a minimum 100 feet from all drainage courses. A 12-inch high compacted earthen berm capable of retaining potential spills shall enclose fueling areas. Other secondary containment devices can be used instead of the earthen berm. The area shall be covered with a non-porous lining to prevent soil contamination. Printed instructions for cleanup procedures shall be posted in the fueling area and appropriate fuel absorbents shall be available along with containers for used absorbents. 3.7 Vehicle Tracking Control In addition to the vehicle tracking pads discussed previously, additional measures can be taken to minimize and control sediment discharges from the site due to vehicle tracking. These measures can include fencing around the site to control access points. Regular street sweeping can also be used to minimize the transmission of sediment from the site due to vehicles leaving the site. The use of gravel parking areas and wash racks can also be implemented to ensure minimal vehicle tracking from the site. Minimizing or limiting the number of vehicles accessing the site by providing designated delivery areas, or by restricting deliveries when the site is muddy is also encouraged. 3.8 Waste Management and Disposal It will be the responsibility of the contractor to designate a concrete truck chute washout area and to clearly identify that area. Detailed information about the design and maintenance of the Concrete Washout can be found under the Structural Practices section of this report. At no time should untreated wash water be allowed to discharge from the site or to enter a storm drain system or stream. Upon completion of construction activities the concrete washout material shall be removed and properly disposed of prior to the area being restored. Any waste material that currently exists on the site or that is generated by construction will be disposed of in such a manner as to not cause pollutants in stormwater discharges. If waste is to be stored on-site, it shall be in an area located a minimum of 100 feet from all drainage courses. Whenever waste is not stored in a non-porous container, it shall be in an area enclosed by a 12- inch high compacted earthen berm or some other approved secondary containment device. The area shall be covered with a non-porous lining to prevent soil contamination. Whenever precipitation is predicted, the waste shall be covered with a non-porous cover and anchored on all sides to prevent its removal by wind. On-site waste disposal practices, such as dumpsters, should be covered or otherwise contained as to prevent dispersion of waste materials by wind. It shall also be the responsibility of the contractor to maintain a clean jobsite and to prevent the dispersion of waste material and potential pollutants into adjacent properties or waterways. The location of, and protective measures for, temporary restroom facilities shall be the responsibility of the SWMP Administrator. The District at Campus West Stormwater Management Plan 11 3.9 Groundwater and Stormwater Dewatering The BMPs selected for construction dewatering vary depending on the site-specific features, such as soils, topography, discharge quantities and discharge location. Typically, dewatering involves pumping water from an inundated area to a BMP, prior to the water being released downstream into a receiving waterway, sediment basin, or well-vegetated area. Acceptable BMPs included discharging water into a sediment trap or basin, using a dewatering filter bag, or using a series of sediment logs. A settlement tank or an active treatment system can also be utilized. Another commonly used method to handle the pumped water is the “sprinkler method,” which involves applying the water to vegetated areas through a perforated discharge hose. Dispersal from a water truck for dust control can also be used to disperse the pumped water. The District at Campus West Stormwater Management Plan 12 4.0 Final Stabilization and Long-Term Stormwater Management 4.1 Final Stabilization All disturbed areas will be seeded, crimped and mulched. Soil amendments, such as compost, peat, aged manure, or other similar materials, shall also be utilized. As defined by the Colorado Department of Public Health and Environment in the General Permit Application for Stormwater Discharges, “Final stabilization is reached when all soil disturbing activities at the site have been completed, and uniform vegetative cover has been established with a density of at least 70 percent of pre-disturbance levels or equivalent permanent, physical erosion reduction methods have been employed.” 4.2 Long-Term Stormwater Management The primary method of long-term stormwater management will be an ultra urban developed site mostly comprised of rooftop area and concrete. Small pockets of fully landscaped areas will also exist. The District at Campus West Stormwater Management Plan 13 5.0 Inspection, Maintenance and Record Keeping 5.1 BMP Inspection All temporary erosion control facilities shall be inspected at a minimum of once every two (2) weeks and after each significant storm event or snowmelt. Repairs or reconstruction of BMPs, as necessary, shall occur as soon as possible in order to ensure the continued performance of their intended function. It is the responsibility of the SWMP Administrator to conduct bi-weekly inspections, maintain BMPs if needed, keep records of site conditions and inspections and to update the SWMP as necessary. The construction site perimeter, disturbed areas, all applicable/installed erosion and sediment control measures and areas used for material storage that are exposed to precipitation shall be inspected for evidence of, or the potential for, pollutants entering the drainage system. Erosion and sediment control measures identified in the SWMP shall be observed to ensure that they are operating correctly. Particular attention should be paid to areas that have a significant potential for stormwater pollution, such as demolition areas, concrete washout locations and vehicle entries to the site. The inspection must be documented to ensure compliance with the permit requirements. 5.2 BMP Maintenance Any BMPs not operating in accordance with the SWMP must be addressed as soon as possible to prevent the discharge of pollutants. If modifications are necessary, such modifications shall be documented so that the SWMP accurately reflects on-site conditions. The SWMP needs to accurately represent field conditions at all times. Uncontrolled releases of mud, muddy water or measurable amounts of sediment found off-site will be recorded with a brief explanation of the measures taken to clean-up the sediment that has left the site, as well as the measures taken to prevent future releases. This record shall be made available to the appropriate public agencies (Colorado Department of Public Health and Environment, Water Quality Control Division; Environmental Protection Agency; City of Fort Collins; etc.) upon request. Preventative maintenance of all temporary and permanent erosion control BMPs shall be provided in order to ensure the continued performance of their intended function. Temporary erosion control measures are to be removed after the site has been sufficiently stabilized as determined by the City of Fort Collins. Maintenance activities and actions to correct problems shall be noted and recorded during inspections. Inspection and maintenance procedures specific to each BMP identified with this SWMP are discussed in Section 3. Details have also been included with Appendix B. 5.3 Record Keeping Documentation of site inspections must be maintained. The following items are to be recorded and kept with the SWMP: x Date of Inspection x Name(s) and title(s) of personnel making the inspection x Location(s) of sediment discharges or other pollutants from the site x Location(s) of BMP’s that need to be maintained x Location(s) of BMP’s that failed to operate as designed or proved inadequate x Locations(s) where additional BMP’s are needed that were not in place at the time of inspection x Deviations from the minimum inspection schedule x Descriptions of corrective action taken to remedy deficiencies that have been identified The District at Campus West Stormwater Management Plan 14 x The report shall contain a signed statement indicating the site is in compliance with the permit to the best of the signer’s knowledge and belief after corrective actions have been taken. Provided in a future submittal within Appendix E of this SWMP will be an Example Inspection Log to aid in the record keeping of BMP inspections and maintenance. Photographs, field notebooks, drawings and maps should be included when appropriate. In addition to the Inspection Log, records should be kept documenting: x BMP maintenance and operation x Stormwater contamination x Contacts with suppliers x Notes on the need for and performance of preventive maintenance and other repairs x Implementation of specific items in the SWMP x Training events (given or attended) x Events involving materials handling and storage x Contacts with regulatory agencies and personnel x Notes of employee activities, contact, notifications, etc. Records of spills, leaks or overflows that result in the discharge of pollutants must be documented and maintained. A record of other spills that are responded to, even if they do not result in a discharge of pollutants, should be made. Information that should be recorded for all occurrences includes the time and date, weather conditions, reasons for the spill, etc. Some spills may need to be reported to authorities immediately. Specifically, a release of any chemical, oil, petroleum product, sewage, etc., which may enter waters of the State of Colorado (which include surface water, ground water and dry gullies or storm sewers leading to surface water) must be reported to the CDPHE. Additionally, the “Dynamic Site Plan” is intended to be a “living document” where the SWMP Administrator can hand write the location of BMPs as they are installed to accurately reflect the current site conditions. Also on the “Dynamic Site Plan” should be a “Table of Construction Sequence and BMP Application/Removal” that the SWMP Administrator can use to document when BMPs were installed or removed in conjunction with construction activities. These items will be included as an aid to the SWMP Administrator, and other methods of record keeping are at his or her discretion. This Stormwater Management Plan (both the text and map) is not a static document, it is a dynamic device intended to be kept current and logged as construction takes place. It shall be the responsibility of the SWMP Administrator and/or the permit holder (or applicant thereof) to ensure the plan is properly maintained and followed. Diligent administration is critical, including processing the Notice to Proceed and noting on the Stormwater Management Plan the dates that various construction activities occur and respective BMPs are installed and/or removed. The District at Campus West Stormwater Management Plan 15 6.0 Additional SWMP and BMP Resources Urban Drainage and Flood Control District Urban Storm Drainage Criteria Manual - Volume 3 “Best Management Practices” Colorado Department of Transportation Erosion Control and Stormwater Quality Guide BMP Field Academy EPA Menu of BMP’s Construction Site Storm Water Runoff Control International Stormwater Best Management (BMP) Database Rocky Mountain Education Center Rocky Mountain Education Center Red Rocks Community College, Lakewood Keep It Clean Partnership Boulder The District at Campus West Stormwater Management Plan 16 References 1. Final Drainage Report for The District at Campus West, Northern Engineering Services, December 5, 2012 (NES Project No. 670-001) 2. Geotechnical Engineering Report, The District at CSU East of West Plum Street and City Park Avenue Fort Collins, Colorado, November 2, 2011, Terracon Consultants, Inc. (Terracon Project No. 20115026) 3. Soil Resource Report for Larimer County Area, Colorado, Natural Resources Conservation Service, United States Department of Agriculture. 4. Urban Storm Drainage Criteria Manual, Volumes 1-3, Urban Drainage and Flood Control District, Water Resources Publications, LLC., Denver, Colorado, Updated November 2010. APPENDIX A SITE MAPS ST ST ST ST ST ST ST ST ST ST � � � � ��� ��� OHE CO CO CO CO CO CO CO CO CO CO CO DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS ADDITIONAL ROW WIDTH VARIES (SEE PLAT) EXISTING DAISY STREET TO BE VACATED (50' ROW) (700) SUNSTONE CONDOMINIUMS (700) SUNSTONE CONDOMINIUMS EXISTING COLUMBINE STREET TO BE VACATED (50' ROW) � ST ST ST ST ST ST ST ST ST CO CO CO DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS (1201) (733) TAU OF GAMMA PHI BETA SORORITY INC. (728) TAU OF GAMMA PHI BETA SORORITY INC. (700) SUNSTONE CONDOMINIUMS (1225) ZETA TAU ALPHA FRATERNITY EXISTING COLUMBINE STREET TO BE VACATED (50' ROW) 3a 3d 3e 3f 3g 3h OS1 OS2 3b 3c OS5 2a 2b 2c 2d 2f No. Revisions: By: Date: REVIEWED BY: N. Haws DESIGNED BY: DRAWN BY: SCALE: DATE: 12/05/12 PROJECT: 670-001 Sheet Of 39 Sheets THE DISTRICT AT CAMPUS WEST T���� �������� ��� ����������� �� ������� �������� �� N������� E���������� S�������, I��. ��� ��� ��� �� �� ���� ��� ��� ���� �� ������������ ������ ������ ��� ������ �� � P����������� E������� �� ��� ������ �� N������� E���������� S�������, I��. NOT FOR CONSTRUCTION REVIEW SET 12/05/12 200 S���� C������ A�����, S���� 010 F��� C������, C������� 80524 E N G I N E E R I N G � � � � � � �� PHONE: 970.221.4158 FAX: 970.221.4159 ���.�������������������.��� C709 CONSTRUCTION DETAILS K. Brazelton K. Brazelton N/A Date Date Date Date Date Date APPROVED: CHECKED BY: CHECKED BY: CHECKED BY: CHECKED BY: CHECKED BY: City Engineer Water & Wastewater Utility Stormwater Utility Parks & Recreation Traffic Engineer Environmental Planner City of Fort Collins, Colorado UTILITY PLAN APPROVAL CALL 2 BUSINESS DAYS IN ADVANCE BEFORE YOU DIG, GRADE, OR EXCAVATE FOR THE MARKING OF APPENDIX B EROSION CONTROL DETAILS Chapter 7 Construction BMPs November 2010 Urban Drainage and Flood Control District 7-13 Urban Storm Drainage Criteria Manual Volume 3 Final Stabilization ▪ Revegetate Site ▪ Activate Post Construction BMPs (e.g., convert sediment basin to extended detention basin) ▪ Remove Temporary BMPs ▪ Closeout State and Local Stormwater Permits Construction Phase Representative Phases: ▪ Clearing and Grubbing ▪ Rough Grading ▪ Road Construction ▪ Utility and Infrastructure Installation ▪ Vertical Construction (Buildings) ▪ Final Grading Management Practices: ▪ Phase Construction Activities to Minimize Disturbed Area at a Given Time ▪ Sequence Contruction within Phases to Avoid Idle Disturbed Areas ▪ Install, Inspect and Proactively Maintain BMPs Appropriate for Each Phase of Construction ▪ Maintain and Update SWMP as Construction Progresses Pre-Construction ▪ Develop Site Plan ▪ Obtain Site Survey, Hydrology and Soils Information ▪ Prepare SWMP ▪ Obtain Stormwater Construction Permits (State and Local) ▪ Obtain Other Relevant Permits (e.g., 404 , Floodplain, Dewatering) Figure 7-2. Construction Stormwater Management Construction BMPs Construction BMPs 7-14 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Functions Erosion Control Sediment Control Site/Material Management Surface Roughening Yes No No Temporary/Permanent Seeding Yes No No Soil Binders Yes No Moderate Mulching Yes Moderate No Compost Blankets and Filter Berms Yes Moderate No Rolled Erosion Control Products Yes No No Temporary Slope Drains Yes No No Temporary Outlet Protection Yes Moderate No Rough Cut Street Control Yes Moderate No Earth Dikes / Drainage Swales Yes Moderate No Terracing Yes Moderate No Check Dams Yes Moderate No Streambank Stabilization Yes No No Wind Erosion / Dust Control Yes No Moderate Silt Fence No Yes No Sediment Control Log Moderate Yes No Straw Bale Barrier No Moderate No Brush Barrier Moderate Moderate No Rock Sock (perimeter control) No Yes No Inlet Protection (various forms) No Yes No Sediment Basins No Yes No Sediment Traps No Yes No Vegetative Buffers Moderate Yes Yes Chemical Treatment Moderate Yes No Concrete Washout Area No No Yes Stockpile Management Yes Yes Yes Good Houskeeping (multiple practices) No No Yes Construction Phasing Moderate Moderate Yes Protection of Existing Vegetation Yes Moderate Yes Construction Fence No No Yes Vehicle Tracking Control Moderate Yes Yes Stabilized Construction Roadway Yes Moderate Yes Stabilized Staging Area Yes Moderate Yes Street Sweeping / Vacuuming No Yes Yes Temporary Diversion Channel Yes No No Dewatering Operations Moderate Yes Yes Temporary Stream Crossing Yes Yes No Temporary Batch Plants No No Yes Paving and Grinding Operations No No Yes Site Management and Other Specific Practices Sediment Control BMPs Erosion Control BMPs Materials Management Table 7-2. Overview of Construction BMPs 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. Soil Binders (SB) EC-3 November 2010 Urban Drainage and Flood Control District SB-1 Urban Storm Drainage Criteria Manual Volume 3 Description Soil binders include a broad range of treatments that can be applied to exposed soils for temporary stabilization to reduce wind and water erosion. Soil binders may be applied alone or as tackifiers in conjunction with mulching and seeding applications. Acknowledgement: This BMP Fact Sheet has been adapted from the 2003 California Stormwater Quality Association (CASQA) Stormwater BMP Handbook: Construction (www.cabmphandbooks.com). Appropriate Uses Soil binders can be used for short-term, temporary stabilization of soils on both mild and steep slopes. Soil binders are often used in areas where work has temporarily stopped, but is expected to resume before revegetation can become established. Binders are also useful on stockpiled soils or where temporary or permanent seeding has occurred. Prior to selecting a soil binder, check with the state and local jurisdiction to ensure that the chemicals used in the soil binders are allowed. The water quality impacts of some types of soil binders are relatively unknown and may not be allowed due to concerns about potential environmental impacts. Soil binders must be environmentally benign (non-toxic to plant and animal life), easy to apply, easy to maintain, economical, and should not stain paved or painted surfaces. Soil binders should not be used in vehicle or pedestrian high traffic areas, due to loss in effectiveness under these conditions. Site soil type will dictate appropriate soil binders to be used. Be aware that soil binders may not function effectively on silt or clay soils or highly compacted areas. Check manufacturer's recommendations for appropriateness with regard to soil conditions. Some binders may not be suitable for areas with existing vegetation. Design and Installation Properties of common soil binders used for erosion control are provided in Table SB-1. Design and installation guidance below are provided for general reference. Follow the manufacturer's instructions for application rates and procedures. Soil Binders Functions Erosion Control Yes Sediment Control No Site/Material Management Moderate Photograph SB-1. Tackifier being applied to provide temporary soil stabilization. Photo courtesy of Douglas County. EC-3 Soil Binders (SB) SB-2 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Table SB-1. Properties of Soil Binders for Erosion Control (Source: CASQA 2003) Evaluation Criteria Binder Type Plant Material Based (short lived) Plant Material Based (long lived) Polymeric Emulsion Blends Cementitious- Based Binders Resistance to Leaching High High Low to Moderate Moderate Resistance to Abrasion Moderate Low Moderate to High Moderate to High Longevity Short to Medium Medium Medium to Long Medium Minimum Curing Time before Rain 9 to 18 hours 19 to 24 hours 0 to 24 hours 4 to 8 hours Compatibility with Existing Vegetation Good Poor Poor Poor Mode of Degradation Biodegradable Biodegradable Photodegradable/ Chemically Degradable Photodegradable/ Chemically Degradable Specialized Application Equipment Water Truck or Hydraulic Mulcher Water Truck or Hydraulic Mulcher Water Truck or Hydraulic Mulcher Water Truck or Hydraulic Mulcher Liquid/Powder Powder Liquid Liquid/Powder Powder Surface Crusting Yes, but dissolves on rewetting Yes Yes, but dissolves on rewetting Yes Clean Up Water Water Water Water Erosion Control Application Rate Varies Varies Varies 4,000 to 12,000 lbs/acre Typ. Soil Binders (SB) EC-3 November 2010 Urban Drainage and Flood Control District SB-3 Urban Storm Drainage Criteria Manual Volume 3 Factors to consider when selecting a soil binder generally include:  Suitability to situation: Consider where the soil binder will be applied, if it needs a high resistance to leaching or abrasion, and whether it needs to be compatible with existing vegetation. Determine the length of time soil stabilization will be needed, and if the soil binder will be placed in an area where it will degrade rapidly. In general, slope steepness is not a discriminating factor.  Soil types and surface materials: Fines and moisture content are key properties of surface materials. Consider a soil binder's ability to penetrate, likelihood of leaching, and ability to form a surface crust on the surface materials.  Frequency of application: The frequency of application can be affected by subgrade conditions, surface type, climate, and maintenance schedule. Frequent applications could lead to high costs. Application frequency may be minimized if the soil binder has good penetration, low evaporation, and good longevity. Consider also that frequent application will require frequent equipment clean up. An overview of major categories of soil binders, corresponding to the types included in Table SB-1 follows. Plant-Material Based (Short Lived) Binders  Guar: A non-toxic, biodegradable, natural galactomannan-based hydrocolloid treated with dispersant agents for easy field mixing. It should be mixed with water at the rate of 11 to 15 lbs per 1,000 gallons. Recommended minimum application rates are provided in Table SB-2. Table SB-2. Application Rates for Guar Soil Stabilizer Slope (H:V) Flat 4:1 3:1 2:1 1:1 Application Rate (lb/acre) 40 45 50 60 70  Psyllium: Composed of the finely ground muciloid coating of plantago seeds that is applied as a wet slurry to the surface of the soil. It dries to form a firm but rewettable membrane that binds soil particles together but permits germination and growth of seed. Psyllium requires 12 to 18 hours drying time. Application rates should be from 80 to 200 lbs/acre, with enough water in solution to allow for a uniform slurry flow.  Starch: Non-ionic, cold-water soluble (pre-gelatinized) granular cornstarch. The material is mixed with water and applied at the rate of 150 lb/acre. Approximate drying time is 9 to 12 hours. Plant-Material Based (Long Lived) Binders  Pitch and Rosin Emulsion: Generally, a non-ionic pitch and rosin emulsion has a minimum solids content of 48 percent. The rosin should be a minimum of 26 percent of the total solids content. The soil stabilizer should be a non-corrosive, water dilutable emulsion that upon application cures to a water insoluble binding and cementing agent. For soil erosion control applications, the emulsion is diluted and should be applied as follows: o For clayey soil: 5 parts water to 1 part emulsion EC-3 Soil Binders (SB) SB-4 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 o For sandy soil: 10 parts water to 1 part emulsion Application can be by water truck or hydraulic seeder with the emulsion and product mixture applied at the rate specified by the manufacturer. Polymeric Emulsion Blend Binders  Acrylic Copolymers and Polymers: Polymeric soil stabilizers should consist of a liquid or solid polymer or copolymer with an acrylic base that contains a minimum of 55 percent solids. The polymeric compound should be handled and mixed in a manner that will not cause foaming or should contain an anti-foaming agent. The polymeric emulsion should not exceed its shelf life or expiration date; manufacturers should provide the expiration date. Polymeric soil stabilizer should be readily miscible in water, non-injurious to seed or animal life, non-flammable, should provide surface soil stabilization for various soil types without inhibiting water infiltration, and should not re-emulsify when cured. The applied compound should air cure within a maximum of 36 to 48 hours. Liquid copolymer should be diluted at a rate of 10 parts water to 1 part polymer and the mixture applied to soil at a rate of 1,175 gallons/acre.  Liquid Polymers of Methacrylates and Acrylates: This material consists of a tackifier/sealer that is a liquid polymer of methacrylates and acrylates. It is an aqueous 100 percent acrylic emulsion blend of 40 percent solids by volume that is free from styrene, acetate, vinyl, ethoxylated surfactants or silicates. For soil stabilization applications, it is diluted with water in accordance with manufacturer's recommendations, and applied with a hydraulic seeder at the rate of 20 gallons/acre. Drying time is 12 to 18 hours after application.  Copolymers of Sodium Acrylates and Acrylamides: These materials are non-toxic, dry powders that are copolymers of sodium acrylate and acrylamide. They are mixed with water and applied to the soil surface for erosion control at rates that are determined by slope gradient, as summarized in Table SB-3. Table SB-3. Application Rates for Copolymers of Sodium Acrylates and Acrylamides Slope (H:V) Flat to 5:1 5:1 to 3:1 2:2 to 1:1 Application Rate (lb/acre) 3.0-5.0 5.0-10.0 10.0-20.0  Polyacrylamide and Copolymer of Acrylamide: Linear copolymer polyacrylamide is packaged as a dry flowable solid. When used as a stand-alone stabilizer, it is diluted at a rate of 11 lb/1,000 gal. of water and applied at the rate of 5.0 lb/acre.  Hydrocolloid Polymers: Hydrocolloid Polymers are various combinations of dry flowable polyacrylamides, copolymers, and hydrocolloid polymers that are mixed with water and applied to the soil surface at rates of 55 to 60 lb/acre. Drying times are 0 to 4 hours. Cementitious-Based Binders  Gypsum: This formulated gypsum based product readily mixes with water and mulch to form a thin protective crust on the soil surface. It is composed of high purity gypsum that is ground, calcined and processed into calcium sulfate hemihydrate with a minimum purity of 86 percent. It is mixed in a hydraulic seeder and applied at rates 4,000 to 12,000 lb/acre. Drying time is 4 to 8 hours. Soil Binders (SB) EC-3 November 2010 Urban Drainage and Flood Control District SB-5 Urban Storm Drainage Criteria Manual Volume 3 Installation After selecting an appropriate soil binder, the untreated soil surface must be prepared before applying the soil binder. The untreated soil surface must contain sufficient moisture to assist the agent in achieving uniform distribution. In general, the following steps should be followed:  Follow manufacturer's written recommendations for application rates, pre-wetting of application area, and cleaning of equipment after use.  Prior to application, roughen embankment and fill areas.  Consider the drying time for the selected soil binder and apply with sufficient time before anticipated rainfall. Soil binders should not be applied during or immediately before rainfall.  Avoid over spray onto roads, sidewalks, drainage channels, sound walls, existing vegetation, etc.  Soil binders should not be applied to frozen soil, areas with standing water, under freezing or rainy conditions, or when the temperature is below 40°F during the curing period.  More than one treatment is often necessary, although the second treatment may be diluted or have a lower application rate.  Generally, soil binders require a minimum curing time of 24 hours before they are fully effective. Refer to manufacturer's instructions for specific cure time.  For liquid agents: o Crown or slope ground to avoid ponding. o Uniformly pre-wet ground at 0.03 to 0.3 gal/yd2 or according to manufacturer's recommendations. o Apply solution under pressure. Overlap solution 6 to 12 in. o Allow treated area to cure for the time recommended by the manufacturer, typically at least 24 hours. o Apply second treatment before first treatment becomes ineffective, using 50 percent application rate. o In low humidity, reactivate chemicals by re-wetting with water at 0.1 to 0.2 gal/yd2. Maintenance and Removal Soil binders tend to break down due to natural weathering. Weathering rates depend on a variety of site- specific and product characteristics. Consult the manufacturer for recommended reapplication rates and reapply the selected soil binder as needed to maintain effectiveness. Soil binders can fail after heavy rainfall events and may require reapplication. In particular, soil binders will generally experience spot failures during heavy rainfall events. If runoff penetrates the soil at the top of a slope treated with a soil binder, it is likely that the runoff will undercut the stabilized soil layer and discharge at a point further down slope. EC-3 Soil Binders (SB) SB-6 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Areas where erosion is evident should be repaired and soil binder or other stabilization reapplied, as needed. Care should be exercised to minimize the damage to protected areas while making repairs. Most binders biodegrade after exposure to sun, oxidation, heat and biological organisms; therefore, removal of the soil binder is not typically required. 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. Compost Blanket and Filter Berm (CB) EC-5 November 2010 Urban Drainage and Flood Control District CB-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph CB-1. Application of a compost blanket to a disturbed area. Photo courtesy of Caltrans. Description A compost blanket is a layer of compost uniformly applied to the soil in disturbed areas to control erosion, facilitate revegetation, and retain sediment resulting from sheet-flow runoff. A compost filter berm is a dike of compost or a compost product that is placed perpendicular to runoff to control erosion in disturbed areas and retain sediment. Compost berms can be placed at regular intervals to help reduce the formation of rill and gully erosion when a compost blanket is stabilizing a slope. Appropriate Uses Compost blankets can be used as an alternative to erosion control blankets and mulching to help stabilize disturbed areas where sheet flow conditions are present. Compost blankets should not be used in areas of concentrated flows. Compost provides an excellent source of nutrients for plant growth, and should be considered for use in areas that will be permanently vegetated. Design and Installation See Detail CB-1 for design details and notes. Do not place compost in areas where it can easily be transported into drainage pathways or waterways. When using a compost blanket on a slope, berms should be installed periodically to reduce the potential for concentrated flow and rilling. Seeding should be completed before an area is composted or incorporated into the compost. Compost quality is an important consideration when selecting compost blankets or berms. Representative compost quality factors include pH, salinity, moisture content, organic matter content, stability (maturity), and physical contaminants. The compost should meet all local, state, and federal quality requirements. Biosolids compost must meet the Standards for Class A biosolids outlined in 40 CFR Part 503. The U.S. Composting Council (USCC) certifies compost products under its Seal of Testing Assurance (STA) Program. Compost producers whose products have been certified through the STA Program provide customers with a standard product label that allows comparison between compost products. Only STA certified, Class I compost should be used. Compost Blankets and Berms Functions Erosion Control Yes Sediment Control Moderate Site/Material Management No EC-5 Compost Blanket and Filter Berm (CB) CB-2 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Maintenance and Removal When rills or gullies develop in an area that has been composted, fill and cover the area with additional compost and install berms as necessary to help reduce erosion. Weed control can be a maintenance challenge in areas using compost blankets. A weed control strategy may be necessary, including measures such as mechanical removal and spot application of targeted herbicides by licensed applicators. For compost berms, accumulated sediments should be removed from behind the berm when the sediments reach approximately one third the height of the berm. Areas that have been washed away should be replaced. If the berm has experienced significant or repeated washouts, a compost berm may not be the appropriate BMP for this area. Compost blankets and berms biodegrade and do not typically require removal following site stabilization. Compost Blanket and Filter Berm (CB) EC-5 November 2010 Urban Drainage and Flood Control District CB-3 Urban Storm Drainage Criteria Manual Volume 3 EC-5 Compost Blanket and Filter Berm (CB) CB-4 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Rough Cut Street Control (RCS) EC-9 November 2010 Urban Drainage and Flood Control District RCS-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph RCS-1. Rough cut street controls. Description Rough cut street controls are rock or earthen berms placed along dirt roadways that are under construction or used for construction access. These temporary berms intercept sheet flow and divert runoff from the roadway, and control erosion by minimizing concentration of flow and reducing runoff velocity. Appropriate Uses Appropriate uses include:  Temporary dirt construction roadways that have not received roadbase.  Roadways under construction that will not be paved within 14 days of final grading, and that have not yet received roadbase. Design and Installation Rough cut street controls are designed to redirect sheet flow off the dirt roadway to prevent water from concentrating and eroding the soil. These controls consist of runoff barriers that are constructed at intervals along the road. These barriers are installed perpendicular to the longitudinal slope from the outer edge of the roadside swale to the crown of the road. The barriers are positioned alternately from the right and left side of the road to allow construction traffic to pass in the lane not barred. If construction traffic is expected to be congested and a vehicle tracking control has been constructed, rough-cut street controls may be omitted for 400 feet from the entrance. Runoff from the controls should be directed to another stormwater BMP such as a roadside swale with check dams once removed from the roadway. See Detail RCS-1 for additional information. Maintenance and Removal Inspect street controls for erosion and stability. If rills are forming in the roadway or cutting through the control berms, place the street controls at shorter intervals. If earthen berms are used, periodic recompaction may be necessary. When rock berms are used, repair and/or replace as necessary when damaged. Street controls may be removed 14 days prior to road surfacing and paving. Rough Cut Street Control Functions Erosion Control Yes Sediment Control Moderate Site/Material Management No EC-9 Rough Cut Street Control (RCS) RCS-2 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Rough Cut Street Control (RCS) EC-9 November 2010 Urban Drainage and Flood Control District RCS-3 Urban Storm Drainage Criteria Manual Volume 3 Earth Dikes and Drainage Swales (ED/DS) EC-10 November 2010 Urban Drainage and Flood Control District ED/DS-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph ED/DS-1. Example of an earth dike used to divert flows at a construction site. Photo courtesy of CDOT. Description Earth dikes and drainage swales are temporary storm conveyance channels constructed either to divert runoff around slopes or to convey runoff to additional sediment control BMPs prior to discharge of runoff from a site. Drainage swales may be lined or unlined, but if an unlined swale is used, it must be well compacted and capable of resisting erosive velocities. Appropriate Uses Earth dikes and drainage swales are typically used to control the flow path of runoff at a construction site by diverting runoff around areas prone to erosion, such as steep slopes. Earth dikes and drainage swales may also be constructed as temporary conveyance features. This will direct runoff to additional sediment control treatment BMPs, such as sediment traps or basins. Design and Installation When earth dikes are used to divert water for slope protection, the earth dike typically consists of a horizontal ridge of soil placed perpendicular to the slope and angled slightly to provide drainage along the contour. The dike is used in conjunction with a swale or a small channel upslope of the berm to convey the diverted water. Temporary diversion dikes can be constructed by excavation of a V-shaped trench or ditch and placement of the fill on the downslope side of the cut. There are two types of placement for temporary slope diversion dikes:  A dike located at the top of a slope to divert upland runoff away from the disturbed area and convey it in a temporary or permanent channel.  A diversion dike located at the base or mid-slope of a disturbed area to intercept runoff and reduce the effective slope length. Depending on the project, either an earth dike or drainage swale may be more appropriate. If there is a need for cut on the project, then an excavated drainage swale may be better suited. When the project is primarily fill, then a conveyance constructed using a berm may be the better option. All dikes or swales receiving runoff from a disturbed area should direct stormwater to a sediment control BMP such as a sediment trap or basin. Earth Dikes and Drainage Swales Functions Erosion Control Yes Sediment Control Moderate Site/Material Management No EC-10 Earth Dikes and Drainage Swales (ED/DS) ED/DS-2 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Unlined dikes or swales should only be used for intercepting sheet flow runoff and are not intended for diversion of concentrated flows. Details with notes are provided for several design variations, including: ED-1. Unlined Earth Dike formed by Berm DS-1. Unlined Excavated Swale DS-2. Unlined Swale Formed by Cut and Fill DS-3. ECB-lined Swale DS-4. Synthetic-lined Swale DS-5. Riprap-lined Swale The details also include guidance on permissible velocities for cohesive channels if unlined approaches will be used. Maintenance and Removal Inspect earth dikes for stability, compaction, and signs of erosion and repair. Inspect side slopes for erosion and damage to erosion control fabric. Stabilize slopes and repair fabric as necessary. If there is reoccurring extensive damage, consider installing rock check dams or lining the channel with riprap. If drainage swales are not permanent, remove dikes and fill channels when the upstream area is stabilized. Stabilize the fill or disturbed area immediately following removal by revegetation or other permanent stabilization method approved by the local jurisdiction. Earth Dikes and Drainage Swales (ED/DS) EC-10 November 2010 Urban Drainage and Flood Control District ED/DS-3 Urban Storm Drainage Criteria Manual Volume 3 EC-10 Earth Dikes and Drainage Swales (ED/DS) ED/DS-4 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Earth Dikes and Drainage Swales (ED/DS) EC-10 November 2010 Urban Drainage and Flood Control District ED/DS-5 Urban Storm Drainage Criteria Manual Volume 3 Check Dams (CD) EC-12 November 2010 Urban Drainage and Flood Control District CD-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph CD-1. Rock check dams in a roadside ditch. Photo courtesy of WWE. Description Check dams are temporary grade control structures placed in drainage channels to limit the erosivity of stormwater by reducing flow velocity. Check dams are typically constructed from rock, gravel bags, sand bags, or sometimes, proprietary devices. Reinforced check dams are typically constructed from rock and wire gabion. Although the primary function of check dams is to reduce the velocity of concentrated flows, a secondary benefit is sediment trapping upstream of the structure. Appropriate Uses Use as a grade control for temporary drainage ditches or swales until final soil stabilization measures are established upstream and downstream. Check dams can be used on mild or moderately steep slopes. Check dams may be used under the following conditions:  As temporary grade control facilities along waterways until final stabilization is established.  Along permanent swales that need protection prior to installation of a non-erodible lining.  Along temporary channels, ditches or swales that need protection where construction of a non- erodible lining is not practicable.  Reinforced check dams should be used in areas subject to high flow velocities. Design and Installation Place check dams at regularly spaced intervals along the drainage swale or ditch. Check dams heights should allow for pools to develop upstream of each check dam, extending to the downstream toe of the check dam immediately upstream. When rock is used for the check dam, place rock mechanically or by hand. Do not dump rocks into the drainage channel. Where multiple check dams are used, the top of the lower dam should be at the same elevation as the toe of the upper dam. When reinforced check dams are used, install erosion control fabric under and around the check dam to prevent erosion on the upstream and downstream sides. Each section of the dam should be keyed in to reduce the potential for washout or undermining. A rock apron upstream and downstream of the dam may be necessary to further control erosion. Check Dams Functions Erosion Control Yes Sediment Control Moderate Site/Material Management No EC-12 Check Dams (CD) CD-2 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Design details with notes are provided for the following types of check dams:  Rock Check Dams (CD-1)  Reinforced Check Dams (CD-2) Sediment control logs may also be used as check dams; however, silt fence is not appropriate for use as a check dam. Many jurisdictions also prohibit or discourage use of straw bales for this purpose. Maintenance and Removal Replace missing rocks causing voids in the check dam. If gravel bags or sandbags are used, replace or repair torn or displaced bags. Remove accumulated sediment, as needed to maintain BMP effectiveness, typically before the sediment depth upstream of the check dam is within ½ of the crest height. Remove accumulated sediment prior to mulching, seeding, or chemical soil stabilization. Removed sediment can be incorporated into the earthwork with approval from the Project Engineer, or disposed of at an alternate location in accordance with the standard specifications. Check dams constructed in permanent swales should be removed when perennial grasses have become established, or immediately prior to installation of a non-erodible lining. All of the rock and accumulated sediment should be removed, and the area seeded and mulched, or otherwise stabilized. Check Dams (CD) EC-12 November 2010 Urban Drainage and Flood Control District CD-3 Urban Storm Drainage Criteria Manual Volume 3 EC-12 Check Dams (CD) CD-4 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Check Dams (CD) EC-12 November 2010 Urban Drainage and Flood Control District CD-5 Urban Storm Drainage Criteria Manual Volume 3 EC-12 Check Dams (CD) CD-6 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Wind Erosion/Dust Control (DC) EC-14 November 2010 Urban Drainage and Flood Control District DC-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph DC-1. Water truck used for dust suppression. Photo courtesy of Douglas County. Description Wind erosion and dust control BMPs help to keep soil particles from entering the air as a result of land disturbing construction activities. These BMPs include a variety of practices generally focused on either graded disturbed areas or construction roadways. For graded areas, practices such as seeding and mulching, use of soil binders, site watering, or other practices that provide prompt surface cover should be used. For construction roadways, road watering and stabilized surfaces should be considered. Appropriate Uses Dust control measures should be used on any site where dust poses a problem to air quality. Dust control is important to control for the health of construction workers and surrounding waterbodies. Design and Installation The following construction BMPs can be used for dust control:  An irrigation/sprinkler system can be used to wet the top layer of disturbed soil to help keep dry soil particles from becoming airborne.  Seeding and mulching can be used to stabilize disturbed surfaces and reduce dust emissions.  Protecting existing vegetation can help to slow wind velocities across the ground surface, thereby limiting the likelihood of soil particles to become airborne.  Spray-on soil binders form a bond between soil particles keeping them grounded. Chemical treatments may require additional permitting requirements. Potential impacts to surrounding waterways and habitat must be considered prior to use.  Placing rock on construction roadways and entrances will help keep dust to a minimum across the construction site.  Wind fences can be installed on site to reduce wind speeds. Install fences perpendicular to the prevailing wind direction for maximum effectiveness. Maintenance and Removal When using an irrigation/sprinkler control system to aid in dust control, be careful not to overwater. Overwatering will cause construction vehicles to track mud off-site. Wind Erosion Control/ Dust Control Functions Erosion Control Yes Sediment Control No Site/Material Management Moderate 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 Vegetated Buffers (VB) SC-9 November 2010 Urban Drainage and Flood Control District VB-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph VB-1. A vegetated buffer is maintained between the area of active construction and the drainage swale. Photo courtesy of WWE. Description Buffer strips of preserved natural vegetation or grass help protect waterways and wetlands from land disturbing activities. Vegetated buffers improve stormwater runoff quality by straining sediment, promoting infiltration, and slowing runoff velocities. Appropriate Uses Vegetated buffers can be used to separate land disturbing activities and natural surface waters or conveyances. In many jurisdictions, local governments require some type of setback from natural waterways. Concentrated flow should not be directed through a buffer; instead, runoff should be in the form of sheet flow. Vegetated buffers are typically used in combination with other perimeter control BMPs such as sediment control logs or silt fence for multi- layered protection. Design and Installation Minimum buffer widths may vary based on local regulations. Clearly delineate the boundary of the natural buffer area using construction fencing, silt fence, or a comparable technique. In areas that have been cleared and graded, vegetated buffers such as sod can also be installed to create or restore a vegetated buffer around the perimeter of the site. Maintenance and Removal Inspect buffer areas for signs of erosion such as gullies or rills. Stabilize eroding areas, as needed. If erosion is due to concentrated flow conditions, it may be necessary to install a level spreader or other technique to restore sheet flow conditions. Inspect perimeter controls delineating the vegetative buffer and repair or replace as needed. Vegetated Buffers Functions Erosion Control Moderate Sediment Control Yes Site/Material Management Yes Chemical Treatment (CT) SC-10 November 2010 Urban Drainage and Flood Control District CT-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph CT-1. Proprietary chemical treatment system being used on a construction site with sensitive receiving waters. Photo courtesy of WWE. Description Chemical treatment for erosion and sediment control can take several forms: 1. Applying chemicals to disturbed surfaces to reduce erosion (these uses are discussed in the Soil Binders Fact Sheet). 2. Adding flocculants to sedimentation ponds or tanks to enhance sediment removal prior. 3. Using proprietary barriers or flow- through devices containing flocculants (e.g., "floc logs"). The use of flocculants as described in No. 2 and No. 3 above will likely require special permitting. Check with the state permitting agency. See the Soil Binder BMP Fact Sheet for information on surface application of chemical treatments, as described in No. 1. Appropriate Uses At sites with fine-grained materials such as clays, chemical addition to sedimentation ponds or tanks can enhance settling of suspended materials through flocculation. Prior to selecting and using chemical treatments, it is important to check state and local permit requirements related to their use. Design and Installation Due to variations among proprietary chemical treatment methods, design details are not provided for this BMP. Chemical feed systems for sedimentation ponds, settling tanks and dewatering bags should be installed and operated in accordance with manufacturer's recommendations and applicable regulations. Alum and chitosan are two common chemicals used as flocculants. Because the potential long-term impact of these chemicals to natural drainageways is not yet fully understood, the state does not currently allow chemical addition under the CDPS General Stormwater Construction Discharge Permit. Additional permitting may be necessary, which may include sampling requirements and numeric discharge limits. Any devices or barriers containing chemicals should be installed following manufacturer's guidelines. Check for state and local jurisdiction usage restrictions and requirements before including these practices in the SWMP and implementing them onsite. Chemical Treatment Functions Erosion Control Moderate Sediment Control Yes Site/Material Management No SC-10 Chemical Treatment (CT) CT-2 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Maintenance and Removal Chemical feed systems for sedimentation ponds or tanks should be maintained in accordance with manufacturer's recommendations and removed when the systems are no longer being used. Accumulated sediment should be dried and disposed of either at a landfill or in accordance with applicable regulations. Barriers and devices containing chemicals should be removed and replaced when tears or other damage to the devices are observed. These barriers should be removed and properly disposed of when the site has been stabilized. Construction Phasing/Sequencing (CP) SM-1 November 2010 Urban Drainage and Flood Control District CP-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph CP-1. Construction phasing to avoid disturbing the entire area at one time. Photo courtesy of WWE. Description Effective construction site management to minimize erosion and sediment transport includes attention to construction phasing, scheduling, and sequencing of land disturbing activities. On most construction projects, erosion and sediment controls will need to be adjusted as the project progresses and should be documented in the SWMP. Construction phasing refers to disturbing only part of a site at a time to limit the potential for erosion from dormant parts of a site. Grading activities and construction are completed and soils are effectively stabilized on one part of a site before grading and construction begins on another portion of the site. Construction sequencing or scheduling refers to a specified work schedule that coordinates the timing of land disturbing activities and the installation of erosion and sediment control practices. Appropriate Uses All construction projects can benefit from upfront planning to phase and sequence construction activities to minimize the extent and duration of disturbance. Larger projects and linear construction projects may benefit most from construction sequencing or phasing, but even small projects can benefit from construction sequencing that minimizes the duration of disturbance. Typically, erosion and sediment controls needed at a site will change as a site progresses through the major phases of construction. Erosion and sediment control practices corresponding to each phase of construction must be documented in the SWMP. Design and Installation BMPs appropriate to the major phases of development should be identified on construction drawings. In some cases, it will be necessary to provide several drawings showing construction-phase BMPs placed according to stages of development (e.g., clearing and grading, utility installation, active construction, final stabilization). Some municipalities in the Denver area set maximum sizes for disturbed area associated with phases of a construction project. Additionally, requirements for phased construction drawings vary among local governments within the UDFCD boundary. Some local governments require separate erosion and sediment control drawings for initial BMPs, interim conditions (in active construction), and final stabilization. Construction Scheduling Functions Erosion Control Moderate Sediment Control Moderate Site/Material Management Yes SM-1 Construction Phasing/Sequencing (CP) CP-2 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Typical construction phasing BMPs include:  Limit the amount of disturbed area at any given time on a site to the extent practical. For example, a 100-acre subdivision might be constructed in five phases of 20 acres each.  If there is carryover of stockpiled material from one phase to the next, position carryover material in a location easily accessible for the pending phase that will not require disturbance of stabilized areas to access the stockpile. Particularly with regard to efforts to balance cut and fill at a site, careful planning for location of stockpiles is important. Typical construction sequencing BMPs include:  Sequence construction activities to minimize duration of soil disturbance and exposure. For example, when multiple utilities will occupy the same trench, schedule installation so that the trench does not have to be closed and opened multiple times.  Schedule site stabilization activities (e.g., landscaping, seeding and mulching, installation of erosion control blankets) as soon as feasible following grading.  Install initial erosion and sediment control practices before construction begins. Promptly install additional BMPs for inlet protection, stabilization, etc., as construction activities are completed. Table CP-1 provides typical sequencing of construction activities and associated BMPs. Maintenance and Removal When the construction schedule is altered, erosion and sediment control measures in the SWMP and construction drawings should be appropriately adjusted to reflect actual "on the ground" conditions at the construction site. Be aware that changes in construction schedules can have significant implications for site stabilization, particularly with regard to establishment of vegetative cover. Construction Phasing/Sequencing (CP) SM-1 November 2010 Urban Drainage and Flood Control District CP-3 Urban Storm Drainage Criteria Manual Volume 3 Table CP-1. Typical Phased BMP Installation for Construction Projects Project Phase BMPs Pre- disturbance, Site Access  Install sediment controls downgradient of access point (on paved streets this may consist of inlet protection).  Establish vehicle tracking control at entrances to paved streets. Fence as needed.  Use construction fencing to define the boundaries of the project and limit access to areas of the site that are not to be disturbed. Note: it may be necessary to protect inlets in the general vicinity of the site, even if not downgradient, if there is a possibility that sediment tracked from the site could contribute to the inlets. Site Clearing and Grubbing  Install perimeter controls as needed on downgradient perimeter of site (silt fence, wattles, etc).  Limit disturbance to those areas planned for disturbance and protect undisturbed areas within the site (construction fence, flagging, etc).  Preserve vegetative buffer at site perimeter.  Create stabilized staging area.  Locate portable toilets on flat surfaces away from drainage paths. Stake in areas susceptible to high winds.  Construct concrete washout area and provide signage.  Establish waste disposal areas.  Install sediment basins.  Create dirt perimeter berms and/or brush barriers during grubbing and clearing.  Separate and stockpile topsoil, leave roughened and/or cover.  Protect stockpiles with perimeter control BMPs. Stockpiles should be located away from drainage paths and should be accessed from the upgradient side so that perimeter controls can remain in place on the downgradient side. Use erosion control blankets, temporary seeding, and/or mulch for stockpiles that will be inactive for an extended period.  Leave disturbed area of site in a roughened condition to limit erosion. Consider temporary revegetation for areas of the site that have been disturbed but that will be inactive for an extended period.  Water to minimize dust but not to the point that watering creates runoff. SM-1 Construction Phasing/Sequencing (CP) CP-4 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Project Phase BMPs Utility And Infrastructure Installation In Addition to the Above BMPs:  Close trench as soon as possible (generally at the end of the day).  Use rough-cut street control or apply road base for streets that will not be promptly paved.  Provide inlet protection as streets are paved and inlets are constructed.  Protect and repair BMPs, as necessary.  Perform street sweeping as needed. Building Construction In Addition to the Above BMPs:  Implement materials management and good housekeeping practices for home building activities.  Use perimeter controls for temporary stockpiles from foundation excavations.  For lots adjacent to streets, lot-line perimeter controls may be necessary at the back of curb. Final Grading In Addition to the Above BMPs:  Remove excess or waste materials.  Remove stored materials. Final Stabilization In Addition to the Above BMPs:  Seed and mulch/tackify.  Seed and install blankets on steep slopes.  Remove all temporary BMPs when site has reached final stabilization. Protection of Existing Vegetation (PV) SM-2 November 2010 Urban Drainage and Flood Control District PV-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph PV-1. Protection of existing vegetation and a sensitive area. Photo courtesy of CDOT. Description Protection of existing vegetation on a construction site can be accomplished through installation of a construction fence around the area requiring protection. In cases where upgradient areas are disturbed, it may also be necessary to install perimeter controls to minimize sediment loading to sensitive areas such as wetlands. Existing vegetation may be designated for protection to maintain a stable surface cover as part of construction phasing, or vegetation may be protected in areas designated to remain in natural condition under post-development conditions (e.g., wetlands, mature trees, riparian areas, open space). Appropriate Uses Existing vegetation should be preserved for the maximum practical duration on a construction site through the use of effective construction phasing. Preserving vegetation helps to minimize erosion and can reduce revegetation costs following construction. Protection of wetland areas is required under the Clean Water Act, unless a permit has been obtained from the U.S. Army Corps of Engineers (USACE) allowing impacts in limited areas. If trees are to be protected as part of post-development landscaping, care must be taken to avoid several types of damage, some of which may not be apparent at the time of injury. Potential sources of injury include soil compaction during grading or due to construction traffic, direct equipment-related injury such as bark removal, branch breakage, surface grading and trenching, and soil cut and fill. In order to minimize injuries that may lead to immediate or later death of the tree, tree protection zones should be developed during site design, implemented at the beginning of a construction project, as well as continued during active construction. Design and Installation General Once an area has been designated as a preservation area, there should be no construction activity allowed within a set distance of the area. Clearly mark the area with construction fencing. Do not allow stockpiles, equipment, trailers or parking within the protected area. Guidelines to protect various types of existing vegetation follow. Protection of Existing Vegetation Functions Erosion Control Yes Sediment Control Moderate Site/Material Management Yes SM-2 Protection of Existing Vegetation (PV) PV-2 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Surface Cover During Phased Construction Install construction fencing or other perimeter controls around areas to be protected from clearing and grading as part of construction phasing. Maintaining surface cover on steep slopes for the maximum practical duration during construction is recommended. Open Space Preservation Where natural open space areas will be preserved as part of a development, it is important to install construction fencing around these areas to protect them from compaction. This is particularly important when areas with soils with high infiltration rates are preserved as part of LID designs. Preserved open space areas should not be used for staging and equipment storage. Wetlands and Riparian Areas Install a construction fence around the perimeter of the wetland or riparian (streamside vegetation) area to prevent access by equipment. In areas downgradient of disturbed areas, install a perimeter control such as silt fence, sediment control logs, or similar measure to minimize sediment loading to the wetland. Tree Protection 1  Before beginning construction operations, establish a tree protection zone around trees to be preserved by installing construction fences. Allow enough space from the trunk to protect the root zone from soil compaction and mechanical damage, and the branches from mechanical damage (see Table PV-1). If low branches will be kept, place the fence outside of the drip line. Where this is not possible, place fencing as far away from the trunk as possible. In order to maintain a healthy tree, be aware that about 60 percent of the tree's root zone extends beyond the drip line. Table PV-1 Guidelines for Determining the Tree Protection Zone (Source: Matheny and Clark, 1998; as cited in GreenCO and WWE 2008) Distance from Trunk (ft) per inch of DBH Species Tolerance to Damage Young Mature Over mature Good 0.5' 0.75' 1.0' Moderate 0.75' 1.0' 1.25' Poor 1.0' 1.25' 1.5' Notes: DBH = diameter at breast height (4.5 ft above grade); Young = <20% of life expectancy; Mature = 20%-80% of life expectancy; Over mature =>80% of life expectancy  Most tree roots grow within the top 12 to 18 inches of soil. Grade changes within the tree protection zone should be avoided where possible because seemingly minor grade changes can either smother 1 Tree Protection guidelines adapted from GreenCO and WWE (2008). Green Industry Best Management Practices (BMPs) for the Conservation and Protection of Water Resources in Colorado: Moving Toward Sustainability, Third Release. See www.greenco.org for more detailed guidance on tree preservation. Protection of Existing Vegetation (PV) SM-2 November 2010 Urban Drainage and Flood Control District PV-3 Urban Storm Drainage Criteria Manual Volume 3 roots (in fill situations) or damage roots (in cut situations). Consider small walls where needed to avoid grade changes in the tree protection zone.  Place and maintain a layer of mulch 4 to 6-inch thick from the tree trunk to the fencing, keeping a 6-inch space between the mulch and the trunk. Mulch helps to preserve moisture and decrease soil compaction if construction traffic is unavoidable. When planting operations are completed, the mulch may be reused throughout planting areas.  Limit access, if needed at all, and appoint one route as the main entrance and exit to the tree protection zone. Within the tree protection zone, do not allow any equipment to be stored, chemicals to be dumped, or construction activities to take place except fine grading, irrigation system installation, and planting operations. These activities should be conducted in consultation with a landscaping professional, following Green Industry BMPs.  Be aware that soil compaction can cause extreme damage to tree health that may appear gradually over a period of years. Soil compaction is easier to prevent than repair. Maintenance and Removal Repair or replace damaged or displaced fencing or other protective barriers around the vegetated area. If damage occurs to a tree, consult an arborist for guidance on how to care for the tree. If a tree in a designated preservation area is damaged beyond repair, remove and replace with a 2-inch diameter tree of the same or similar species. Construction equipment must not enter a wetland area, except as permitted by the U.S. Army Corps of Engineers (USACE). Inadvertent placement of fill in a wetland is a 404 permit violation and will require notification of the USACE. If damage to vegetation occurs in a protected area, reseed the area with the same or similar species, following the recommendations in the USDCM Revegetation chapter. 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 Stabilized Construction Roadway (SCR) SM-5 November 2010 Urban Drainage and Flood Control District SCR-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph SCR-1. Stabilized construction roadway. Description A stabilized construction roadway is a temporary method to control sediment runoff, vehicle tracking, and dust from roads during construction activities. Appropriate Uses Use on high traffic construction roads to minimize dust and erosion. Stabilized construction roadways are used instead of rough-cut street controls on roadways with frequent construction traffic. Design and Installation Stabilized construction roadways typically involve two key components: 1) stabilizing the road surface with an aggregate base course of 3-inch-diameter granular material and 2) stabilizing roadside ditches, if applicable. Early application of road base is generally suitable where a layer of coarse aggregate is specified for final road construction. Maintenance and Removal Apply additional gravel as necessary to ensure roadway integrity. Inspect drainage ditches along the roadway for erosion and stabilize, as needed, through the use of check dams or rolled erosion control products. Gravel may be removed once the road is ready to be paved. Prior to paving, the road should be inspected for grade changes and damage. Regrade and repair as necessary. Stabilized Construction Roadway Functions Erosion Control Yes Sediment Control Moderate Site/Material Management Yes 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 Dewatering Operations (DW) SM-9 November 2010 Urban Drainage and Flood Control District DW-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph DW-1. A relatively small dewatering operation using straw bales and a dewatering bag. Photograph DW-2. Dewatering bags used for a relatively large dewatering operation. Description The BMPs selected for construction dewatering vary depending on site- specific features such as soils, topography, anticipated discharge quantities, and discharge location. Dewatering typically involves pumping water from an inundated area to a BMP, and then downstream to a receiving waterway, sediment basin, or well- vegetated area. Dewatering typically involves use of several BMPs in sequence. Appropriate Uses Dewatering operations are used when an area of the construction site needs to be dewatered as the result of a large storm event, groundwater, or existing ponding conditions. This can occur during deep excavation, utility trenching, and wetland or pond excavation. Design and Installation Dewatering techniques will vary depending on site conditions. However, all dewatering discharges must be treated to remove sediment before discharging from the construction site. Discharging water into a sediment trap or basin is an acceptable treatment option. Water may also be treated using a dewatering filter bag, and a series of straw bales or sediment logs. If these previous options are not feasible due to space or the ability to passively treat the discharge to remove sediment, then a settling tank or an active treatment system may need to be utilized. Settling tanks are manufactured tanks with a series of baffles to promote settling. Flocculants can also be added to the tank to induce more rapid settling. This is an approach sometimes used on highly urbanized construction sites. Contact the state agency for special requirements prior to using flocculents and land application techniques. Some commonly used methods to handle the pumped water without surface discharge include land application to vegetated areas through a perforated discharge hose (i.e., the "sprinkler method") or dispersal from a water truck for dust control. Dewatering Operations Functions Erosion Control Moderate Sediment Control Yes Site/Material Management Yes SM-9 Dewatering Operations (DW) DW-2 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Dewatering discharges to non-paved areas must minimize the potential for scour at the discharge point either using a velocity dissipation device or dewatering filter bag. Design Details are provided for these types of dewatering situations: DW-1. Dewatering for Pond Already Filled with Water DW-2 Dewatering Sump for Submersed Pump DW-3 Sump Discharge Settling Basin DW-4 Dewatering Filter Bag Maintenance and Removal When a sediment basin or trap is used to enable settling of sediment from construction dewatering discharges, inspect the basin for sediment accumulation. Remove sediment prior to the basin or trap reaching half full. Inspect treatment facilities prior to any dewatering activity. If using a sediment control practice such as a sediment trap or basin, complete all maintenance requirements as described in the fact sheets prior to dewatering. Properly dispose of used dewatering bags, as well as sediment removed from the dewatering BMPs. Depending on the size of the dewatering operation, it may also be necessary to revegetate or otherwise stabilize the area where the dewatering operation was occurring. Dewatering Operations (DW) SM-9 November 2010 Urban Drainage and Flood Control District DW-3 Urban Storm Drainage Criteria Manual Volume 3 SM-9 Dewatering Operations (DW) DW-4 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Dewatering Operations (DW) SM-9 November 2010 Urban Drainage and Flood Control District DW-5 Urban Storm Drainage Criteria Manual Volume 3 Paving and Grinding Operations (PGO) SM-12 November 2010 Urban Drainage and Flood Control District PGO-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph PGO-1. Paving operations on a Colorado highway. Photo courtesy of CDOT. Description Manage runoff from paving and grinding operations to reduce pollutants entering storm drainage systems and natural drainageways. Appropriate Uses Use runoff management practices during all paving and grinding operations such as surfacing, resurfacing, and saw cutting. Design and Installation There are a variety of management strategies that can be used to manage runoff from paving and grinding operations:  Establish inlet protection for all inlets that could potentially receive runoff.  Schedule paving operations when dry weather is forecasted.  Keep spill kits onsite for equipment spills and keep drip pans onsite for stored equipment.  Install perimeter controls when asphalt material is used on embankments or shoulders near waterways, drainages, or inlets.  Do not wash any paved surface into receiving storm drain inlets or natural drainageways. Instead, loose material should be swept or vacuumed following paving and grinding operations.  Store materials away from drainages or waterways.  Recycle asphalt and pavement material when feasible. Material that cannot be recycled must be disposed of in accordance with applicable regulations. See BMP Fact Sheets for Inlet Protection, Silt Fence and other perimeter controls selected for use during paving and grinding operations. Maintenance and Removal Perform maintenance and removal of inlet protection and perimeter controls in accordance with their respective fact sheets. Promptly respond to spills in accordance with the spill prevention and control plan. Paving and Grinding Operations Functions Erosion Control No Sediment Control No Site/Material Management Yes APPENDIX C LANDSCAPE PLAN APPENDIX D COPIES OF PERMITS/APPLICATIONS APPENDIX E INSPECTION LOGS APPENDIX F CONTRACTOR INSERTS APPENDIX G CONTRACTOR INSERTS UNDERGROUND MEMBER UTILITIES. CALL UTILITY NOTIFICATION CENTER OF COLORADO Know what'sbelow. Call before you dig. R VEHICLE CONTROL TRACKING PAD NOT TO SCALE COMPACTED BACKFILL FLOW SILT TRENCH FENCE AND FABRIC ATTACHED (ASTM TO D6461) POST. ANCHORED IN 24" MIN 6' MAX FLOW TRENCH AND ATTACHED TO POST. 4"x4" TRENCH SILT FENCE FABRIC (ASTM D6461) ANCHORED IN 18" MIN 24" MIN 42" MIN POSTS {PREASSEMBLED SILT FENCE} JOIN FIRST ROTATE SECOND POSTS SHALL OVERLAP AT JOINTS SO THAT NO GAPS EXIST IN SILT FENCE. NOTE: THICKNESS OF GEOTEXTILE HAS BEEN EXAGGERATED. POST SHALL BE JOINED AS SHOWN, THEN ROTATED 180� IN DIRECTION SHOWN AND DRIVEN INTO THE GROUND. {SILT FENCE JOINTS} DRIVE POSTS VERTICALLY INTO THE GROUND TO A MINIMUM DEPTH OF 18". EXCAVATE A TRENCH APPROXIMATELY 4" WIDE AND 4" DEEP ALONG THE LINE OF POSTS AND UPSLOPE FROM THE BARRIER. ANCHOR TRENCH SHALL BE EXCAVATED BY HAND, WITH TRENCHER, OR WITH SILT FENCE INSTALLATION MACHINE. NO ROAD GRADERS, BACKHOES, ETC. SHALL BE USED. NOT LESS THAN THE BOTTOM 1' OF THE SILT FENCE FABRIC SHALL BE BURIED IN THE TRENCH. THE TRENCH SHALL BE COMPACTED BY HAND, WITH "JUMPING JACK" OR BY WHEEL ROLLING. COMPACTION SHALL BE SUCH THAT THE SILT FENCE RESISTS BEING PULLED OUT OF ANCHOR TRENCH BY HAND. SILT FENCE INDICATED IN THE PLANS SHALL BE INSTALLED PRIOR TO ANY LAND-DISTURBING ACTIVITIES. USE WOOD POSTS OR OTHER MATERIAL AS ACCEPTED BY THE CITY. {INSTALLATION NOTES: }1. 2. 3. 4. 5. 6. 7. THE CONTRACTOR SHALL INSPECT SILT FENCE EVERY TWO WEEKS AND AFTER SIGNIFICANT STORM EVENTS AND MAKE REPAIRS OR CLEAN OUT UPSTREAM SEDIMENT AS NECESSARY. SEDIMENT ACCUMULATED UPSTREAM OF SILT FENCE SHALL BE REMOVED WHEN THE UPSTREAM SEDIMENT REACHES A DEPTH OF 6". SILT FENCE SHALL BE REMOVED WHEN THE UPSTREAM DISTURBED AREA IS STABILIZED AND GRASS COVER IS ACCEPTED BY THE CITY. IF ANY DISTURBED AREA EXISTS AFTER REMOVAL, IT SHALL BE SEEDED AND MULCHED OR OTHERWISE STABILIZED IN A MANNER ACCEPTED BY THE CITY. {MAINTENANCE NOTES: }1. 2. 3. 4" MIN. 4" MIN. {1 " x 1 " WOODEN FENCE POSTS} COMPACTED BACKFILL MANHOLE ROCK BERM SHALL 2"x 4" WOOD STUD EXTENDED INTO CONCRETE BLOCKS WIRE ENCLOSED 1 1/2" WASHED ROCK CONCRETE BLOCKS CURB INLET GRAVEL FILTER WIRE SHALL ENCLOSED BE 2"x4" WOOD STUD OVERFLOW FILTERED RUNOFF %SECTION A-A A A %PLAN VIEW {CURB INLET GRAVEL FILTER (CONTINUOUS GRADE)} %SECTION B-B %PLAN VIEW B B ROCK BERM SHALL BE PLACED TIGHTLY AGAINST CURB FACE WIRE ENCLOSED 1 1/2" WASHED ROCK CURB AND GUTTER CURB AND GUTTER BE PLACED TIGHTLY AGAINST CURB FACE GRAVEL FILTER 1/2" TO 1" BELOW TOP OF CURB TUBULAR MARKER IF AREA ADJACENT TO CURB INLET BOX IS NOT STABILIZED, INSTALL A TEMPORARY SEDIMENT/EROSION CONTROL BMP UNTIL THE SURROUNDING AREA IS SUFFICIENTLY STABILIZED. TUBULAR MARKER TUBULAR MARKER 2' 3' 4' CURB INLET WIRE ENCLOSED SETTLED RUNOFF GRAVEL FILTER CURB INLET MANHOLE {CURB INLET BLOCK AND GRAVEL FILTER (INLET IN SUMP)} INTERIM CONFIGURATION INLET PROTECTION IN STREETS SHALL BE INSTALLED WITHIN 48 HOURS OF POURING INLET. INLET PROTECTION (AFTER PAVING) SHALL BE INSTALLED WITHIN 48 HOURS AFTER PAVING IS PLACED. WASHED ROCK SHALL COMPLY WITH A 1-1/2" MINUS GRADATION. WIRE MESH SHALL BE FABRICATED OF 10 GAUGE WIRE TWISTED INTO A MESH WITH A MAXIMUM OPENING OF 1" (COMMONLY TERMED "CHICKEN WIRE"). ROLL WIDTH SHALL BE 48". TUBULAR MARKERS SHALL MEET REQUIREMENTS OF MANUAL ON UNIFORM TRAFFIC CONTROL DEVICES (MUTCD). OTHER CURB INLET PROTECTION METHODS WILL BE ALLOWED IF ACCEPTED BY THE CITY. {GENERAL NOTES: }1. 2. 3. 4. 5. THE CONTRACTOR SHALL INSPECT INLET PROTECTION EVERY TWO WEEKS AND AFTER SIGNIFICANT STORM EVENTS AND MAKE REPAIRS OR CLEAN OUT AS NECESSARY. SEDIMENT ACCUMULATED UPSTREAM OF INLET PROTECTION SHALL BE REMOVED WHEN THE SEDIMENT DEPTH UPSTREAM OF ROCK BERM IS 2 1/2" OF THE CREST. INLET PROTECTION IS TO REMAIN IN PLACE UNTIL THE UPSTREAM DISTURBED AREA IS STABILIZED AND GRASS COVER IS ACCEPTED. UNLESS THE CITY ACCEPTS EARLIER REMOVAL OF INLET PROTECTION IN STREETS. {MAINTENANCE NOTES: }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x 1" WOOD STAKES 18"-24" BAILING WIRE OR NYLON ROPE WATTLE "A" WATTLE "B" 1' 2' TYP. 1' 1' WATTLES - DETAIL B W2 NOTES: INSTALLATION: STAKES SHOULD BE DRIVEN ACROSS FROM EACH OTHER AND ON EACH SIDE OF THE WATTLE. LEAVING 4"-6" OF STAKE PROTRUDING ABOVE THE WATTLE. BAILING WIRE OR NYLON ROPE SHOULD BE TIED TO THE STAKES ACROSS THE WATTLE. STAKES SHOULD THEN BE DRIVEN UNTIL THE BAILING WIRE OR NYLON ROPE IS SUFFICIENTLY SNUG TO THE WATTLE. WHEN INSTALLING RUNNING LENGTHS OF WATTLES, TO PREVENT SHIFTING, BUTT THE SECOND WATTLE TIGHTLY AGAINST THE FIRST. DO NOT OVERLAP THE ENDS. STAKES SHOULD BE DRIVEN 1 FT. FROM END, ACROSS FROM AND ON EACH SIDE OF WATTLE LEAVING 4"-6" OF STAKE PROTRUDING ABOVE THE WATTLE. BAILING WIRE OR NYLON ROPE SHOULD BE TIED TO STAKES IN AN HOUR GLASS FORMATION (FRONT TO BACK OF WATTLE "A", ACROSS TO FRONT OF WATTLE "B", ACROSS TO BACK AND BACK TO FRONT OF WATTLE "A"). STAKES SHOULD THEN BE DRIVEN IN UNTIL BAILING WIRE OR NYLON ROPE IS SUFFICIENTLY SNUG TO THE WATTLE. SEDIMENT DEPOSITION ZONE STORM WATER LINE WEIGHTED WATTLE LIP OF GUTTER SIDEWALK EXISTING OR PROPOSED INLET TOP BACK CURB FLOW LINE %CURB INLET WATTLE PROTECTION SETUP% SEDIMENT DEPOSITION ZONE STORM WATER LINE LIP OF GUTTER WEIGHTED WATTLE AT 45 DEG. TO CURB SIDEWALK TOP BACK CURB FLOW LINE SIDEWALK TOP BACK CURB FLOW LINE W4 NOTES: 1. NUMBER OF WATTLES AND SPACING SHOULD BE DETERMINED BY THE SLOPE AND SITE CONDITIONS. 2. TUBULAR MARKERS SHALL MEET THE REQUIREMENTS OF MANUAL ON UNIFORM TRAFFIC CONTROL DEVICES (MUTCD) 3. CITY RECOMMENDS INSTALLING AT LEAST 3 CHECKDAMS WHEN USING THIS SETUP. LIP OF GUTTER WEIGHTED WATTLE W1 & W2 INSTALLATION NOTES: 1. THE LOCATION AND LENGTH OF WATTLE IS DEPENDENT ON THE CONDITIONS OF EACH SITE. 2. WATTLES SHALL BE INSTALLED PRIOR TO ANY LAND-DISTURBING ACTIVITIES. 3. WATTLES SHALL CONSIST OF STRAW, COMPOST, EXCELSIOR, OR COCONUT FIBER. 4. NOT FOR USE IN CONCENTRATED FLOW AREAS. 5. THE WATTLES SHALL BE TRENCHED INTO THE GROUND A MINIMUM OF TWO (2) INCHES. 6. WATTLES SHALL BE INSTALLED PER MANUFACTURERS SPECIFICATIONS. 7. ON SLOPES, WATTLES SHOULD BE INSTALLED ON CONTOUR WITH A SLIGHT DOWNWARD ANGLE AT THE END OF THE ROW IN ORDER TO PREVENT PONDING AT THE MID SECTION. 8. RUNNING LENGTHS OF WATTLES SHOULD BE ABUTTED FIRMLY TO ENSURE NO LEAKAGE AT THE ABUTMENTS. 9. SPACING - DOWNSLOPE: 10. VERTICAL SPACING FOR SLOPE INSTALLATIONS SHOULD BE DETERMINED BY SITE CONDITIONS. SLOPE GRADIENT AND SOIL TYPE ARE THE MAIN FACTORS. A GOOD RULE OF THUMB IS: 1:1 SLOPES = 10 FEET APART 2:1 SLOPES = 20 FEET APART 3:1 SLOPES = 30 FEET APART 4:1 SLOPES = 40 FEET APART, ETC. 11. HOWEVER, ADJUSTMENTS MAY HAVE TO BE MADE FOR THE SOIL TYPE: FOR SOFT, LOAMY SOILS - ADJUST THE ROWS CLOSER TOGETHER; FOR HARD, ROCKY SOILS - ADJUST THE ROWS FURTHER APART. A SECONDARY WATTLE PLACED BEHIND THE ABUTMENT OF TWO WATTLES IS ENCOURAGED ON STEEP SLOPES OR WHERE JOINTS HAVE FAILED IN THE PAST. 12. STAKING: THE CITY RECOMMENDS USING WOOD STAKES TO SECURE THE WATTLES. 1/2" TO 5/8" REBAR IS ALSO ACCEPTABLE. BE SURE TO USE A STAKE THAT IS LONG ENOUGH TO PROTRUDE SEVERAL INCHES ABOVE THE WATTLE: 18" IS A GOOD LENGTH FOR HARD, ROCKY SOIL. FOR SOFT LOAMY SOIL USE A 24" STAKE. SNUG WITH WATTLE. W3 NOTE: IF THE AREA BEHIND THE INLET IS NOT STABILIZED, A BMP SHOULD BE USED TO PREVENT SEDIMENT FROM ENTERING THE INLET 1"x 1" WOOD STAKES 18"-24" W1 THE CONTRACTOR SHALL INSPECT WATTLES EVERY TWO WEEKS AND AFTER ANY SIGNIFICANT STORM EVENT AND MAKE REPAIRS OR REMOVE SEDIMENT ACCUMULATED BEHIND WATTLE AS NECESSARY. SEDIMENT ACCUMULATED BEHIND WATTLE SHALL BE REMOVED WHEN THE SEDIMENT HAS ACCUMULATED TO ONE HALF THE DIAMETER OF THE WATTLE. WATTLES SHALL REMAIN IN PLACE UNTIL THE UPSTREAM DISTURBED AREA IS STABILIZED AND IS ACCEPTED BY THE CITY. WATTLE MAINTENANCE NOTES: 1. 2. 3. ENDS SHALL ABUT TIGHTLY TO BACK OF CURB END SHALL ABUT TIGHTLY TO BACK OF CURB ENDS OF ADJACENT WATTLES SHALL BE TIGHTLY ABUTTED TO PREVENT SEDIMENT BYPASS 4' MAX. {IMPERVIOUS INSTALLATION} SEDIMENT DEPOSITION ZONE W3 W2 NOTE: ONLY WATTLES MADE WITH COCONUT FIBERS SHALL BE USED WHEN INSTALLATION COMES IN CONTACT WITH A WATER BODY. SIDEWALK CULVERT/CHASE/PAN W4 W3, W4 & W5 NOTES: 1. WHEN USING STRAW WATTLE, THE STRAW WATTLE MUST HAVE A WEIGHTED CORE. 2. ALL PRODUCTS SHALL BE INSTALLED PER THE MANUFACTURER'S SPECIFICATIONS. 3. OTHER PRODUCTS MAY BE USED IN PLACE OF WEIGHTED WATTLES UPON WRITTEN APPROVAL FROM THE CITY. NOTE: A COPY OF DETAILS AND SPECIFICATIONS WILL NEED TO BE INCORPORATED INTO THE SWMP. END SHALL TIGHTLY ABUT TO BACK OF CURB SEDIMENT DEPOSITION ZONE W5 TUBULAR MARKER EXISTING OR PROPOSED INLET CONCRETE CHASE/TRICKLE CHANNEL SETUP END SHALL TIGHTLY ABUT TO BACK OF CURB CURBSIDE CHECKDAMS SETUP VEHICLE TRACKING CONTROL PAD SHALL BE LOCATED AT EVERY ACCESS POINT TO THE CONSTRUCTION SITE. A SIGN SHALL BE PLACED NEXT TO THE VEHICLE TRACKING CONTROL PAD TO DESIGNATE THE LOCATION AS THE CONSTRUCTION ENTRANCE/EXIT. VEHICLE TRACKING CONTROL PADS SHALL CONSIST OF HARD, DENSE, DURABLE STONE, ANGULAR IN SHAPE AND RESISTANT TO WEATHERING. ROUNDED STONE (i.e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x4'S, PIPES, DIRT, GRAVEL OR ASPHALT, SHALL BE PLACED IN GUTTER TO FACILITATE MOUNTING CURB; HOWEVER, CURB MAY BE CUT DOWN TO A HEIGHT OF 2" OR HIGHER FOR EASIER ACCESS AND REPLACED AT PROJECT COMPLETION. OTHER ACCESS DEVICES MAY BE USED AS ACCEPTED BY THE CITY. 3" - 6" ROCK %PLAN% CURB CUT 50' MIN. 2" MIN. 6" MIN. 6" MIN. ALTHOUGH NOT NORMALLY USED, THE CITY RESERVES THE RIGHT TO REQUIRE VEHICLE TRACKING CONTROL WITH A TEMPORARY CATTLE GUARD AND/OR WHEEL WASH FACILITIES AT SITES WHERE TRACKING ONTO PAVED AREAS BECOMES A SIGNIFICANT PROBLEM AS DETERMINED BY THE CITY INSPECTOR. IF VEHICLE TRACKING CONTROL WITH WHEEL WASH FACILITIES ARE REQUIRED, ALL WHEELS ON EVERY VEHICLE LEAVING THE SITE SHALL BE CLEANED OF MUD USING A PRESSURE-WASHER. THE CONTRACTOR SHALL BE RESPONSIBLE FOR OBTAINING A WATER SOURCE AND CONSTRUCTING A WASHWATER SEDIMENT TRAP. 5. 6. IF VEHICLE WHEEL WASH FACILITIES ARE REQUIRED, CONTRACTOR SHALL INSPECT VEHICLE TRACKING CONTROL AND WHEEL WASH FACILITIES DAILY. ACCUMULATED SEDIMENTS SHALL BE REMOVED FROM THE PAD SURFACE. ACCUMULATED SEDIMENT IN THE WASHWATER/SEDIMENT TRAP SHALL BE REMOVED WHEN THE SEDIMENT REACHES AN AVERAGE DEPTH OF 12-INCHES. 4. 5. VTC CONCRETE WASHOUT AREA SHALL BE INSTALLED PRIOR TO ANY CONCRETE PLACEMENT ON SITE. VEHICLE TRACKING CONTROL IS REQUIRED IF ACCESS TO CONCRETE WASHOUT AREA IS OFF PAVEMENT. SIGNS SHALL BE PLACED AT THE CONSTRUCTION ENTRANCE, AT THE WASHOUT AREA, AND ELSEWHERE AS NECESSARY TO CLEARLY INDICATE THE LOCATION OF THE CONCRETE WASHOUT AREA TO OPERATORS OF CONCRETE TRUCKS AND PUMP RIGS. THE CONCRETE WASHOUT AREA SHALL BE REPAIRED AND ENLARGED OR CLEANED OUT AS NECESSARY TO MAINTAIN CAPACITY FOR WASTED CONCRETE. AT THE END OF CONSTRUCTION, ALL CONCRETE SHALL BE REMOVED FROM THE SITE AND DISPOSED OF AT AN ACCEPTED WASTE SITE. WHEN THE CONCRETE WASHOUT AREA IS REMOVED, THE DISTURBED AREA SHALL BE SEEDED AND MULCHED OR OTHERWISE STABILIZED IN A MANNER ACCEPTED BY THE CITY. LOCATION OF CONCRETE WASHOUT AREA ON SHEET EC1 IS CONCEPTUAL ONLY. FINAL LOCATION TO BE DETERMINED IN THE FIELD AT CONTRACTOR'S DISCRETION. {NOTES: }1. 2. 3. 4. 5. 6. 7. 3H:1V OR FLATTER SIDE SLOPES 12" MIN 8'x 8' MIN OR AS REQUIRED TO CONTAIN WASTE CONCRETE 12" 2'-0" MIN. COMPACTED EMBANKMENT MATERIAL, TYP. BERM AROUND PERIMETER GROUND SURFACE SIGN TO INDICATE THE LOCATION OF THE CONCRETE WASHOUT AREA CONCRETE WASHOUT AREA NOT TO SCALE CWA SF 1 C709 3 C709 2 C709 4 C709 5 C709 WATTLE WATTLE OR NOTE: INSTALLATION OF WATTLE STAKES MAY VARY WITH NO GAPS (TYP.) TIGHTLY ABUTTING INLET PLAN VIEW ENTRENCH 3" FLOW FLOW NOTE: ENTRENCH WATTLE 3" INTO NATURAL GROUND AT THE OUTSIDE EDGE OF CONCRETE APRON IP NOT TO SCALE 6 DROP INLET PROTECTION C709 WP 2e acres 3a 0.95 0.39 1.00 acres 2a 0.95 0.70 1.00 acres OS5 0.86 0.64 1.00 acres OS2 0.86 0.18 1.00 acres OS1 0.73 0.05 0.91 acres OS3 0.94 0.10 1.00 acres OS4 0.94 0.09 1.00 acres 3b 0.95 0.09 1.00 acres 3c 0.95 0.01 1.00 acres 3d 0.52 0.06 0.64 acres 3f 0.68 0.05 0.84 acres 3e 0.60 0.06 0.76 acres 3h 0.67 0.05 0.83 acres 3g 0.25 0.05 0.31 acres 2b 0.88 0.16 1.00 acres 2d 0.31 0.06 0.39 acres 2c 0.91 0.09 1.00 acres 2e 0.44 0.05 0.55 acres 2f 0.59 0.08 0.73 acres OS0 0.95 0.13 1.00 WP IP IP IP IP IP WP WP WP WP VTC OS3 OS4 VTC BUILDING 2 FFE=5033.34 FFE=5033.00 WEST PLUM STREET (ROW VARIES) WEST PLUM STREET (ROW VARIES) ASTER STREET (50' ROW) FFE=5032.50 BUILDING 3 FFE=5031.34 BLUEBELL STREET (50' ROW) No. Revisions: By: Date: REVIEWED BY: N. Haws DESIGNED BY: DRAWN BY: SCALE: DATE: 12/05/12 PROJECT: 670-001 Sheet Of 39 Sheets THE DISTRICT AT CAMPUS WEST T���� �������� ��� ����������� �� ������� �������� �� N������� E���������� S�������, I��. ��� ��� ��� �� �� ���� ��� ��� ���� �� ������������ ������ ������ ��� ������ �� � P����������� E������� �� ��� ������ �� N������� E���������� S�������, I��. NOT FOR CONSTRUCTION REVIEW SET 12/05/12 200 S���� C������ A�����, S���� 010 F��� C������, C������� 80524 E N G I N E E R I N G � � � � � � �� PHONE: 970.221.4158 FAX: 970.221.4159 ���.�������������������.��� C601 CONTROL PLAN DRAINAGE AND EROSION H. Feissner H. Feissner 1"=30' City UTILITY of Fort PLAN Collins, APPROVAL Colorado Date Date Date Date Date Date APPROVED: City Engineer Traffic Engineer Parks & Recreation Stormwater Utility Water & Wastewater Utility CHECKED BY: CHECKED BY: CHECKED BY: CHECKED BY: CHECKED BY: CALL 2 BUSINESS DAYS IN ADVANCE BEFORE YOU DIG, GRADE, OR EXCAVATE FOR THE MARKING OF UNDERGROUND MEMBER UTILITIES. CALL UTILITY NOTIFICATION CENTER OF COLORADO K��� ����'� �����. C��� ������ ��� ���. R ( IN FEET ) 1 inch = ft. 30 0 30 Feet 30 60 90 LEGEND: NORTH FOR DRAINAGE REVIEW ONLY NOT FOR CONSTRUCTION PROPOSED CONTOURS 80 79 EXISTING TREES EXISTING ROW EXISTING EASEMENT LINE EXISTING CURB & GUTTER PROPOSED SWALE PROPOSED 2.5-FOOT VERTICAL CURB & GUTTER SECTION EXISTING CONCRETE PROPOSED EASEMENT A A 1.23 ac DESIGN POINT FLOW ARROW DRAINAGE BASIN LABEL BASIN DESIGNATION BASIN AREA (AC) DRAINAGE BASIN BOUNDARY NOTES: 1.REFER TO THE "FINAL DRAINAGE & EROSION CONTROL REPORT FOR THE DISTRICT AT CAMPUS WEST' BY NORTHERN ENGINEERING, DATED DECEMBER 5, 2012 FOR ADDITIONAL INFORMATION. 2.THE FINISHED FLOOR ELEVATIONS SHOWN ARE THE MINIMUM ELEVATIONS REQUIRED FOR PROTECTION FROM THE 100-YEAR STORM. WATTLE PROTECTION WP INLET PROTECTION IP VEHICLE TRACKING CONTROL PAD VTC SILT FENCE SF PROPOSED ASPHALT MILL AND OVERLAY PROPOSED CONCRETE PROPOSED LANDSCAPE BED/PLANTER PROPOSED ENHANCED PAVING PROPOSED STORM SEWER PROPOSED STORM INLET PROPOSED STORM MANHOLE PROPOSED PERMEABLE PAVING DRAINAGE SUMMARY TABLE DESIGN POINT BASIN ID TOTAL AREA (�����) C2 C100 2-�� T� (���) 100-�� T� (���) Q2 (���) Q100 (���) B���� 1 1.70 0.82 1.00 7.9 7.6 3.44 14.58 B���� 2 1.20 0.85 1.00 8.6 8.2 2.39 10.05 B���� 3 0.81 0.78 0.97 5.4 5.0 1.79 7.81 1� 1� 0.38 0.95 1.00 5.0 5.0 1.04 3.83 1� 1� 0.31 0.95 1.00 5.0 5.0 0.84 3.10 1� 1� 0.23 0.95 1.00 5.0 5.0 0.64 2.34 1� 1� 0.04 0.28 0.35 5.0 5.0 0.03 0.14 1� 1� 0.04 0.25 0.31 5.0 5.0 0.03 0.13 1� 1� 0.02 0.25 0.31 5.0 5.0 0.01 0.06 1� 1� 0.01 0.95 1.00 5.0 5.0 0.03 0.12 1� 1� 0.21 0.74 0.92 5.0 5.0 0.44 1.91 1� 1� 0.09 0.53 0.67 5.0 5.0 0.14 0.61 1� 1� 0.07 0.77 0.96 5.0 5.0 0.15 0.67 1� 1� 0.03 0.48 0.59 5.0 5.0 0.04 0.16 2� 2� 0.70 0.95 1.00 5.0 5.0 1.90 6.98 2� 2� 0.16 0.88 1.00 5.0 5.0 0.41 1.63 2� 2� 0.09 0.91 1.00 5.0 5.0 0.23 0.88 2� 2� 0.06 0.31 0.39 5.0 5.0 0.06 0.25 2� 2� 0.05 0.44 0.55 5.2 5.0 0.06 0.27 2� 2� 0.08 0.59 0.73 5.0 5.0 0.13 0.58 3� 3� 0.39 0.95 1.00 5.0 5.0 1.04 3.84 3� 3� 0.09 0.95 1.00 5.0 5.0 0.24 0.88 3� 3� 0.01 0.95 1.00 5.0 5.0 0.03 0.12 3� 3� 0.06 0.52 0.64 5.0 5.0 0.09 0.39 3� 3� 0.06 0.60 0.76 5.6 5.2 0.09 0.41 3� 3� 0.05 0.68 0.84 5.0 5.0 0.09 0.41 3� 3� 0.05 0.25 0.31 5.0 5.0 0.03 0.15 3� 3� 0.05 0.67 0.83 5.0 5.0 0.10 0.45 OS0 OS0 0.13 0.95 1.00 5.0 5.0 0.35 1.28 OS1 OS1 0.05 0.73 0.91 5.6 5.4 0.10 0.46 OS2 OS2 0.18 0.86 1.00 5.0 5.0 0.45 1.83 OS3 OS3 0.10 0.94 1.00 5.0 5.0 0.26 0.98 OS4 OS4 0.09 0.94 1.00 5.0 5.0 0.25 0.94 OS5 OS5 0.64 0.86 1.00 8.5 8.2 1.33 5.37 OS5 1�,2� & OS5 0.87 0.86 1.00 8.5 8.2 1.80 7.33 OS4 2�,2� & OS4 0.25 0.76 0.96 5.0 5.0 0.54 2.35 OS3 3� & OS3 0.15 0.84 1.00 5.0 5.0 0.37 1.53 OS5 1�,2�,2�,2�,3�,OS3,OS4 & OS5 1.28 0.84 1.00 8.5 8.2 2.57 10.69 OS1 3� & OS1 0.10 0.70 0.88 5.6 5.4 0.19 0.87 OS2 3�,3�,OS0,OS1,OS2 0.47 0.82 1.00 5.0 5.0 1.10 4.65 OS2 1�,2�,2�,2�,3�,3�,3�,OS0 ���� OS5 1.74 0.83 1.00 11.2 10.9 3.10 13.19 DETENTION POND SUMMARY T�������� A���(�) P��� L������� VOLUME REQUIRED (��-��) VOLUME PROVIDED (��-��) RELEASE RATE (���) DETENTION METHOD WATER QUALITY METHOD 1� & 1� 1� 0.082 0.082 0.71 P�������� P����� P�������� P����� 1� & 1� 1� 0.062 0.062 0.40 P�������� P����� P�������� P����� 2� 2� 0.130 0.130 0.50 D�������� V���� �/�� B������� 2 S��� F����� 1� ���� 1�, 2� & 2� 2� & 2� 0.061 0.610 0.40 P�������� P����� P�������� P����� 3� & 3� 3� 0.033 0.033 1.33 P�������� P����� P�������� P����� KEYMAP NTS WEST PLUM ST. CITY PARK AVE. BLUEBELL ST. ASTER ST. C600 C601 MATCHLINE SEE SHEET C600 2a 2b 1a 1d 1g 1h 1j 1k 1i 1f 2f 2e 1b acres 2a 0.95 0.70 1.00 acres 1a 0.95 0.38 1.00 acres 1b 0.95 0.31 1.00 acres 2e 0.44 0.05 0.55 acres 2f 0.59 0.08 0.73 acres 1c 0.95 0.23 1.00 acres 1h 0.74 0.21 0.92 acres 1i 0.53 0.09 0.67 acres 1j 0.77 0.07 0.96 acres 1j 0.77 0.07 0.96 acres 1g 0.95 0.01 1.00 acres 1k 0.48 0.03 0.59 1e acres 1f 0.25 0.02 0.31 acres 1e 0.25 0.04 0.31 acres 1d 0.28 0.04 0.35 1c IP IP IP IP IP WP 50' EXIST. ROW BUILDING 1 FFE=5036.80 BUILDING 1 FFE=5034.30 BUILDING 2 FFE=5033.34 CITY PARK AVENUE (50' ROW) WEST PLUM STREET (ROW VARIES) BUILDING 1 FFE=5035.30 WEST PLUM STREET (ROW VARIES) No. Revisions: By: Date: REVIEWED BY: N. Haws DESIGNED BY: DRAWN BY: SCALE: DATE: 12/05/12 PROJECT: 670-001 Sheet Of 39 Sheets THE DISTRICT AT CAMPUS WEST T���� �������� ��� ����������� �� ������� �������� �� N������� E���������� S�������, I��. ��� ��� ��� �� �� ���� ��� ��� ���� �� ������������ ������ ������ ��� ������ �� � P����������� E������� �� ��� ������ �� N������� E���������� S�������, I��. NOT FOR CONSTRUCTION REVIEW SET 12/05/12 200 S���� C������ A�����, S���� 010 F��� C������, C������� 80524 E N G I N E E R I N G � � � � � � �� PHONE: 970.221.4158 FAX: 970.221.4159 ���.�������������������.��� C600 CONTROL PLAN DRAINAGE AND EROSION H. Feissner H. Feissner 1"=30' City UTILITY of Fort PLAN Collins, APPROVAL Colorado Date Date Date Date Date Date APPROVED: City Engineer Traffic Engineer Parks & Recreation Stormwater Utility Water & Wastewater Utility CHECKED BY: CHECKED BY: CHECKED BY: CHECKED BY: CHECKED BY: CALL 2 BUSINESS DAYS IN ADVANCE BEFORE YOU DIG, GRADE, OR EXCAVATE FOR THE MARKING OF UNDERGROUND MEMBER UTILITIES. CALL UTILITY NOTIFICATION CENTER OF COLORADO K��� ����'� �����. C��� ������ ��� ���. R ( IN FEET ) 1 inch = ft. 30 0 30 Feet 30 60 90 LEGEND: NORTH FOR DRAINAGE REVIEW ONLY NOT FOR CONSTRUCTION PROPOSED CONTOURS 80 79 EXISTING TREES EXISTING ROW EXISTING EASEMENT LINE EXISTING CURB & GUTTER PROPOSED SWALE PROPOSED 2.5-FOOT VERTICAL CURB & GUTTER SECTION EXISTING CONCRETE PROPOSED EASEMENT A A 1.23 ac DESIGN POINT FLOW ARROW DRAINAGE BASIN LABEL BASIN DESIGNATION BASIN AREA (AC) DRAINAGE BASIN BOUNDARY NOTES: 1.REFER TO THE "FINAL DRAINAGE & EROSION CONTROL REPORT FOR THE DISTRICT AT CAMPUS WEST' BY NORTHERN ENGINEERING, DATED DECEMBER 5, 2012 FOR ADDITIONAL INFORMATION. 2.THE FINISHED FLOOR ELEVATIONS SHOWN ARE THE MINIMUM ELEVATIONS REQUIRED FOR PROTECTION FROM THE 100-YEAR STORM. WATTLE PROTECTION WP INLET PROTECTION IP VEHICLE TRACKING CONTROL PAD VTC SILT FENCE SF PROPOSED ASPHALT MILL AND OVERLAY PROPOSED CONCRETE PROPOSED LANDSCAPE BED/PLANTER PROPOSED ENHANCED PAVING PROPOSED STORM SEWER PROPOSED STORM INLET PROPOSED STORM MANHOLE PROPOSED PERMEABLE PAVING DRAINAGE SUMMARY TABLE DESIGN POINT BASIN ID TOTAL AREA (�����) C2 C100 2-�� T� (���) 100-�� T� (���) Q2 (���) Q100 (���) B���� 1 1.70 0.82 1.00 7.9 7.6 3.44 14.58 B���� 2 1.20 0.85 1.00 8.6 8.2 2.39 10.05 B���� 3 0.81 0.78 0.97 5.4 5.0 1.79 7.81 1� 1� 0.38 0.95 1.00 5.0 5.0 1.04 3.83 1� 1� 0.31 0.95 1.00 5.0 5.0 0.84 3.10 1� 1� 0.23 0.95 1.00 5.0 5.0 0.64 2.34 1� 1� 0.04 0.28 0.35 5.0 5.0 0.03 0.14 1� 1� 0.04 0.25 0.31 5.0 5.0 0.03 0.13 1� 1� 0.02 0.25 0.31 5.0 5.0 0.01 0.06 1� 1� 0.01 0.95 1.00 5.0 5.0 0.03 0.12 1� 1� 0.21 0.74 0.92 5.0 5.0 0.44 1.91 1� 1� 0.09 0.53 0.67 5.0 5.0 0.14 0.61 1� 1� 0.07 0.77 0.96 5.0 5.0 0.15 0.67 1� 1� 0.03 0.48 0.59 5.0 5.0 0.04 0.16 2� 2� 0.70 0.95 1.00 5.0 5.0 1.90 6.98 2� 2� 0.16 0.88 1.00 5.0 5.0 0.41 1.63 2� 2� 0.09 0.91 1.00 5.0 5.0 0.23 0.88 2� 2� 0.06 0.31 0.39 5.0 5.0 0.06 0.25 2� 2� 0.05 0.44 0.55 5.2 5.0 0.06 0.27 2� 2� 0.08 0.59 0.73 5.0 5.0 0.13 0.58 3� 3� 0.39 0.95 1.00 5.0 5.0 1.04 3.84 3� 3� 0.09 0.95 1.00 5.0 5.0 0.24 0.88 3� 3� 0.01 0.95 1.00 5.0 5.0 0.03 0.12 3� 3� 0.06 0.52 0.64 5.0 5.0 0.09 0.39 3� 3� 0.06 0.60 0.76 5.6 5.2 0.09 0.41 3� 3� 0.05 0.68 0.84 5.0 5.0 0.09 0.41 3� 3� 0.05 0.25 0.31 5.0 5.0 0.03 0.15 3� 3� 0.05 0.67 0.83 5.0 5.0 0.10 0.45 OS0 OS0 0.13 0.95 1.00 5.0 5.0 0.35 1.28 OS1 OS1 0.05 0.73 0.91 5.6 5.4 0.10 0.46 OS2 OS2 0.18 0.86 1.00 5.0 5.0 0.45 1.83 OS3 OS3 0.10 0.94 1.00 5.0 5.0 0.26 0.98 OS4 OS4 0.09 0.94 1.00 5.0 5.0 0.25 0.94 OS5 OS5 0.64 0.86 1.00 8.5 8.2 1.33 5.37 OS5 1�,2� & OS5 0.87 0.86 1.00 8.5 8.2 1.80 7.33 OS4 2�,2� & OS4 0.25 0.76 0.96 5.0 5.0 0.54 2.35 OS3 3� & OS3 0.15 0.84 1.00 5.0 5.0 0.37 1.53 OS5 1�,2�,2�,2�,3�,OS3,OS4 & OS5 1.28 0.84 1.00 8.5 8.2 2.57 10.69 OS1 3� & OS1 0.10 0.70 0.88 5.6 5.4 0.19 0.87 OS2 3�,3�,OS0,OS1,OS2 0.47 0.82 1.00 5.0 5.0 1.10 4.65 OS2 1�,2�,2�,2�,3�,3�,3�,OS0 ���� OS5 1.74 0.83 1.00 11.2 10.9 3.10 13.19 DETENTION POND SUMMARY T�������� A���(�) P��� L������� VOLUME REQUIRED (��-��) VOLUME PROVIDED (��-��) RELEASE RATE (���) DETENTION METHOD WATER QUALITY METHOD 1� & 1� 1� 0.082 0.082 0.71 P�������� P����� P�������� P����� 1� & 1� 1� 0.062 0.062 0.40 P�������� P����� P�������� P����� 2� 2� 0.130 0.130 0.50 D�������� V���� �/�� B������� 2 S��� F����� 1� ���� 1�, 2� & 2� 2� & 2� 0.061 0.610 0.40 P�������� P����� P�������� P����� 3� & 3� 3� 0.033 0.033 1.33 P�������� P����� P�������� P����� No. Revisions: By: Date: REVIEWED BY: N. Haws DESIGNED BY: DRAWN BY: SCALE: DATE: 12/05/12 PROJECT: 670-001 Sheet Of 39 Sheets THE DISTRICT AT CAMPUS WEST T���� �������� ��� ����������� �� ������� �������� �� N������� E���������� S�������, I��. ��� ��� ��� �� �� ���� ��� ��� ���� �� ������������ ������ ������ ��� ������ �� � P����������� E������� �� ��� ������ �� N������� E���������� S�������, I��. NOT FOR CONSTRUCTION REVIEW SET 12/05/12 200 S���� C������ A�����, S���� 010 F��� C������, C������� 80524 E N G I N E E R I N G � � � � � � �� PHONE: 970.221.4158 FAX: 970.221.4159 ���.�������������������.��� KEYMAP NTS WEST PLUM ST. CITY PARK AVE. BLUEBELL ST. ASTER ST. C600 C601 MATCHLINE SEE SHEET C601