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Home My WebLink AboutSUN COMMUNITIES - THE FOOTHILLS - FDP220005 - SUBMITTAL DOCUMENTS - ROUND 1 - STORMWATER MANAGEMENT PLAN Fort Collins MH Project (The Foothills) Stormwater Management Plan Owner/Developer Sun Communities 27777 Franklin Road, Suite 220 Southfield, MI 48034 (248) 208-2543 Contact: Anastasiya Short Engineer Atwell, LLC 143 Union Blvd., Suite 700 Lakewood, CO 80228 303-825-7100 Contact: Justin Phipps, PE Atwell Project Number 19002763 March 2022 Submitted by: Atwell, LLC Table of Contents PROJECT DESCRIPTION AND NATURE OF CONSTRUCTION ................................................................... 1 POTENTIAL POLLUTANT SOURCES ........................................................................................................ 2 CONSTRUCTION CONTROL MEASURES ................................................................................................. 7 INSTALLATION AND REMOVAL SEQUENCE OF CONSTRUCTION MEASURES ........................................ 9 MAINTENANCE AND INSPECTION REQUIREMENTS ............................................................................ 10 FINAL VEGETATION AND STABILIZATION ............................................................................................ 12 REFERENCES ........................................................................................................................................ 14 APPENDIX A – EROSION CONTROL PLANS APPENDIX B – EROSION CONTROL ESCROW CALCULATION APPENDIX C – COPIES OF PERMITS/APPLICATIONS (TO BE PROVIDED BY CONTRACTOR) APPENDIX D – STORMWATER MANAGEMENT PLAN INSPECTION LOGS APPENDIX E – CONTRACTOR INSERTS APPENDIX F – REFERENCE MATERIAL Page 1 PROJECT DESCRIPTION AND NATURE OF CONSTRUCTION SITE LOCATION The Fort Collins MH Project (The Foothills), (Site) is located in the northwest and northeast quarter of Section 13, Township 6 North, Range 69 West of the Sixth Principal Meridian, County of Larimer, State of Colorado. The Site is comprised of two parcels of land that are located within the City of Fort Collins, adjacent to South College Avenue and East Trilby Road. The site is approximately 52.65 acres. There is an existing manufactured housing community and a single-family residential neighborhood adjacent to the Site on the north, existing multi-family residential developments on the east, and vacant land to the south. A proposed multi-family development that is currently under construction is located south of the Site adjacent to College Ave. and the City of Fort Collins owns the vacant parcel of land east of the proposed multi-family project. The proposed development consists of 52.65 acres and is made up of 205 manufactured homes and open space with access from Trilby Road. The purpose of the land disturbing activities that are to take place in this project is to complete overlot grading, install utilities (electric, gas, telephone/cable, potable water, storm sewer, and sanitary sewer), grading/paving of all roads and excavation and fill required on the site for overlot grading of the lots associated with the project. The actual land disturbing activities will include digging trenches (for utility installation), swales, and storm water detention ponds, and grading the portions of the site upon which the future road and lots will lie. The total area to be disturbed in the project is approximately 44.75 acres. EXISTING SITE CONDITIONS The Site consists of approximately 52.65 acres of existing, undeveloped land to be developed for the manufactured homes and related infrastructure. The existing topography is generally sloping (2% to 5%) towards the northeast corner of the site. There is an area of ponding on the Site that is considered inadvertent storage of stormwater. The City indicated that this area can be used in the proposed detention pond and that specific requirements will apply for the required detention volume; these requirements will be discussed in detail within this report. Existing Land Use for the entire site is designated as a Low-Density Mixed-Use Neighborhood District. The areas surrounding the site consist of Low-Density Mixed-Use Neighborhood District to the north (mobile home park), east (Provincetowne Neighborhood) and south (Stanton Creek Neighborhood) of the site. There is a Low-Density Residential District designation located along the northwestern portion of the site (College Ave and Trilby Road) in additional to a General Commercial District along S. College Ave and an Employment District to the north across Trilby Road. The ground cover of the Site consists of nearly 100% vegetative cover as the site is currently vacant land. There are no designated or named drainageways located within or traversing the site. No FEMA floodplains are delineated on the property. Soils on the site consists of a combination of fine sandy loam and clay loams, the majority of the Site consists of Hydrologic Soil Group C and D, with only 1.3% of the site having a Hydrologic Soil Group B rating which is located in the northeast corner of the property. Soil types were obtained from the Natural Resources Conservation Service (NRCS) – Web Soil Survey. Please see the NRCS soils report for a description of the hydrologic functions of the different soil groups. A wind Page 2 erodibility report has also been included, which should moderate wind erodibility. A detailed NRCS soils map with percentages and descriptions of soils is included in Appendix E. According to the Federal Emergency Management Agency’s (FEMA) Flood Insurance Rate Map, the Site lies within Zone X, which is designated as “Areas determined to be outside the 0.2% annual chance flood hazard area.” The FEMA FIRM panel is not printed for this area. A FIRMette is included in Appendix E for reference. PROPOSED CONSTRUCTION ACTIVITIES The stormwater management control measures for this project will be divided into three sub-phases for BMP installation: initial, interim, and final. Each phase of the SWMP Plans has specific activities associated with it. Areas noted on the plans as to remain undisturbed (outside the LOC) will remain undisturbed, unless these plans are modified and approved by the City. As the methods of controlling erosion and sediment vary by phase, the steps taken will be discussed below in a phase-by-phase basis. Groundwater was encountered between 10 and 24 feet below existing grade. Earthwork calculations have yielded the following results: 1. Excavation: 168,333 cubic yards. 2. Fill: 161,849 cubic yards. 3. Net Adjusted: 6,484 cubic yards EXPORT. 4. Surface Area of Proposed Disturbance: 52.4 acres. Wetlands disturbed and replaced: 4.61 acres Nearest receiving waters: Cache La Poudre River POTENTIAL POLLUTANT SOURCES The following are potential sources of pollution that may reasonably be expected to affect stormwater near a construction site. 1. Disturbed and Stored Soils – Yes – Approximately 85% percent of this site will be disturbed with the Construction Activities. Once soils have been disturbed, they do not retain the same compaction as in their native state, therefore surface runoff can cause more soil erosion than was historically observed. Based upon the site design this site will not disturb all areas of construction until it is required to as part of the Construction Activities (phasing). Once exposed those areas of exposed soils will be kept in a roughened condition (surface roughening). In the event that these erosion control practices do not keep sediment on site a structural barrier (silt fence) will be used and is called out for on the perimeter. If soil manages to migrate from the disturbed areas onto the hard surfaces it will be swept or scraped (street sweeping) to prevent the migration of sediment. In case that sediment is washed away too quickly the curb inlets will need protection (rock sock style inlet protection). Stockpiles in the same respect do not retain the same compaction and are more susceptible to soil erosion. Stockpiles on this site shall be placed in or near the center of the site and away from any drainage swales to not require perimeter run off Page 3 controls (Materials/Site Management Control). The stock pile will be kept loose, not compacted, and watered as needed to prevent dust issues (site watering). The stockpile will be monitored for signs of erosion displacement and sediment accumulation and if conditions warrant it, the stockpile will be structurally covered or if it is going to sit a long while will be reseeded (temporary seeding). 2. Vehicle Tracking of Sediments – Yes – Vehicle tracking of sediment may occur throughout the construction process and along all areas where the pavement meets the disturbed dirt. This occurs most often after any melt off or rain conditions when mud collects on vehicles tires and is tracked out onto the road consequently leaving site. This increases the possibility of sediment discharging to the storm system. To prevent tracking, construction fence (site barrier/site management control) will be used site wide to limit the access by the contractor and their subs to only two construction entrances (vehicle tracking pads to be installed) on the east of the site and the west of the site. There will be a gate at the entrance that will be closed before contractors come on site during the muddy days (site management control) and will only be opened to let larger deliveries drop off, otherwise subcontractor parking will be kept to the street. All contractors have signed contracts that will have them clean the streets if they are found to be tracking dirt onto the street. (site management control). The tracking pad will be monitored visually every day and if track-out becomes a significant problem a larger or more robust tracking pad may be installed. Otherwise, all track-out that reaches the street will be scraped and swept (street sweeping). Secondary controls at the closest affected combination inlets will have protection (drop inlet protection) to capture sediment not swept up in a timely manner. 3. Management of Contaminated Soils – No – Soil borings do not indicate an existing contamination and all data about the site shows that there is no known contamination on the site. If encountered, the contractor will have the material stored in a covered area (materials management control) as to not mix with the stormwater until the material can be identified and proper classification and disposal methods can be determined in accordance with the various waste laws and with good construction safety and practices. 4. Loading and Unloading Operations – Yes – During this project there will be a diverse amount of loading and unloading going on. There will be a significant amount of export leaving the site, the foundation workers will have to deliver forms to the site and deliver premixed concrete. Building materials will have to be staged around the site and Landscapers will have to pile the materials on site to complete the landscape work. Though the loading and unloading vehicles will be contributing to the track out of materials, depending on the material being delivered to the site they may have a significant spill potential. In addition to the vehicle tracking of sediments section of this report, (VTC, Sweeping, etc.) contractors will be required to park their vehicles on the adjacent roadways (site management control). The only vehicles allowed on site will be fork lifts, concrete trucks, and the like (site management control). Where the project is mostly dirt and not stable semi-trailers will be directed to pull alongside the project and site loaders will be used to off load the trailers. Where the trailers must access the site, an attempt will be made to keep the vehicle on the VTC or other stabilized storage areas. Where the site parking lot and private drives have been installed materials will be placed in piles along the hardscape the use of site forklifts Page 4 will be more heavily used. When loading and unloading is occurring, depending on the materials, there may be an increased problem of containers being dropped, punctured, or broken. These off-loading activities will be done under roofs or awnings where possible, locating away from storm drains and will have nearby spill kits accessible. Spills on site will be addressed using spill prevention and response procedures. 5. Outdoor Storage of Construction Site Materials, Building Materials, Fertilizers, and Chemicals – Yes - is anticipated that inert material like wood, shingles, tiles, siding insulation and stone will be stored on site and outside in the elements. It is also anticipated that materials that do not weather well (cement, mortar, etc.) will also be located outside. Chemicals are not anticipated to be left outside. As the inert materials have a lower potential to leave the site, they will be monitored during inspection to make sure they are not being impacted by the exposure to the elements. (site management control) The materials that will need added attention are the cements and mortars as they quickly mix with water and cause pollution issues. These materials when not stored inside will be placed on pallets to get above potential surface runoff and covered with tarps or plastic to prevent mixing with stormwater (materials management control). Very small quantities of chemical are needed to contaminate stormwater so the fertilizers, paints, form oils, petroleum products, and other typical chemicals, will be stored in the construction connex box, trailers, vehicles, or the like out of contact with precipitation (materials management control). If not stored in a location as described, secondary containment will be required. 6. Bulk Storage of Materials – Yes – The spray foam insulation used for the interior will be provided in a 55-gallon drum. The drum has little chance to contribute to runoff as the liquid would quickly turn to foam and solidify thus having little to no discharge from the site. However, these materials should be stored in an area that if a rupture would occur, it is figured that the 55-gallon drum would need 1300 square feet of space to expand so the storage area will need to be located away from the drainage areas and area inlets (site management / materials management). The drums will be stored in secondary containment area with a fence so that if a spill were to happen the foam would pool in the bottom of the area and if it started to over flow the construction fence would act as a net and allow the foam to expand into the fence keeping it in the location (materials management. 7. Vehicle and Equipment Maintenance and Fueling – No – As fueling and equipment maintenance usually result in small spills of petroleum products it is important to monitor these activities carefully. (site management control) Some grading companies will employee a fuel truck to fill the heavy equipment on site or require the maintenance of a broken machine. In those cases where the vehicle is not able to be maintained off site, these activities will be done in the least detrimental way possible. The maintenance and fueling will be located as far from stormwater. 8. Significant Dust or Particulate Generating Processes – Yes – This project will result in earth moving activities, street sweeping, and track-out and carry out, bulk materials transport, and saw cutting. As these activities will result in offsite transport of atmospheric pollution reasonable precautions shall be taken. The project will follow all required “BMPs” articulated in the Fugitive Dust Manual and a least one additional BMP included during each of the identified activities in accordance with City Ordinance No. 044,2016. Also, a copy of the Dust Control Manual will be kept in the trailer Page 5 during construction for reference. Such activities will include but not limited to watering the site, covering trucks, slower site speeds and vehicle tracking mentioned above. 9. Routine Maintenance Activities Involving Fertilizers, Pesticides, Herbicides, Detergents, Fuels, Solvents, and Oils – Yes – Fertilizers and Pesticides will be used during the later phases of the project when trying to establish a healthy vegetation. These chemicals are highly water soluble and are easily and unnoticeably carried in the stormwater. Proper application rates and recommended timing of application will be strictly followed and not on days, or the next day, where the weather is calling for precipitation (materials management control). As most of these types of chemicals will be brought on by the Landscaper, they will be required to keep these products in their vehicles until time of application and not be allowed to leave these materials on the site (site management control). If these materials are stored on site, they shall be kept inside or outside covered and above the ground to prevent the materials from mixing with water and runoff (materials management control). Detergents, paints, acids, cement, grout, and solvents will be prevalent in the interior work of the building (materials management). These materials also are typically easily mixed with water yet are typically noticeable by discolored, cloudy, or sudsy water. As such, the contractor will always keep an eye out for these types of differences in water around the site (site management control). However, these materials are to be handled, operated, and cleaned up all within the inside of the structure, where external use is concerned these materials will be stored in the construction connex box, trailers, vehicles, or the like out of contact with precipitation (materials management). If not stored in a location as described secondary containment will be required (materials management). Fuels and oils might be associated with the smaller equipment used on site, chainsaws, pumps, generators, etc. As petroleum products are easily suspended in water and are spread across the top of the water surface. These products when located in water have rainbow sheen on them. They are also monitored during construction (site management controls). These products will be stored in the construction connex box, trailers, vehicles, or similar structure that will minimize contact with precipitation (materials maintenance controls). If not stored in a location as described secondary containment will be required (materials maintenance). Any untreated runoff from these activities can be detrimental to wildlife if not cleaned up. 10. On-Site Waste Management Practices – Yes – All large and heavy weighted waste piles (concrete chunks, excavated pipes, etc.) will be kept in a neat grouped pile until the material is to be disposed of properly. These piles will only be stored a short duration 5-10 days and will be kept 50 feet from any drainage course or inlet (Administrative Control). All dry wastes will be maintained through dumpsters and monthly hauler removal (hauler will be notified if dumpster becomes full and hauled off as needed). Where available by the hauling company the dumpster will be covered. If not practical or available by the haul company, an increased removal schedule will be followed and the “Max fill line” on the dumpster will be strictly followed. Corners of the dumpsters will be monitored for “Dumpster Juice” leaking into the soil in dry conditions and rain/melt off conditions looking for it is mixing with the runoff. Dumpsters, like the waste piles, will be located at least 50 feet from any drainage course or inlet. Workers will be sent around at Page 6 the end of the day to collect trash to prevent trash being left out overnight. No construction debris (including broken concrete) will be buried on site. 11. Concrete Truck/Equipment Washing, Including the Concrete Truck Chute And Associated Fixtures and Equipment – Yes – Concrete will be a large portion of this project. It is anticipated that it will be used with the joints around the manholes, pour in place inlets, curb and gutter installation, sidewalks, and foundations. Pre mixed concrete trucks will be used in this process and will be delivered to the site and when pouring the foundation, a pump truck will be used all of which will need to be maintained through the washing of their chutes and pump arms to prevent the concrete from hardening and ruining the equipment. This concrete wash water has a high alkaline content which is hazardous material to terrestrial and aquatic wildlife. A section of dirt near the entrance will be excavated and compacted around the sides formed to retain the concrete wash water on site (as an acceptable practice by the State) so long as the wash water is kept in the washout (concrete washout). There will be a rock pad for the truck to park on while washing as to prevent tracking from this washout (VTC). The placement of this washout will be located at least 50 feet from any drainage course or inlet. Later in the project after the parking lots curb and gutter has been poured the use of a mobile washout facility will be used on site in a similar location and after the ground has been leveled (concrete washout – mobile). The contractor (including all masonry and concrete tradesmen) shall clean out equipment within the washout area so that the runoff is not allowed to leave the washout. The only exception would be for them to wash in the next day’s pour location. All concrete workers will be made aware of the where they are to wash (site management controls & education)., If there is a significant amount of spillage when the transfer from concrete truck to pump truck occurs, a tarp or other ground cloth should be used to collect spillage. (ground cover control). 12. Dedicated Asphalt, Concrete Batch Plants – No - There will be no dedicated asphalt or concrete batch plants erected onsite for this project. Premixed concrete and paving materials will be delivered to the site and placed. 13. Non-Industrial Waste Sources Such As Worker Trash And Portable Toilets – Yes – Since facilities are not located nearby for workers to use, trash and sanitary facilities will be required on the site. Worker trash will be comingled with the industrial trash and will follow the same controls with the caveat that a trashcan will be located near the entrance of the site as the contractor will need to dump their trash from lunch, etc. and this will be emptied weekly or more frequently, if needed. If tipped over and when being cleaned, portable toilet facilities become a potential discharge if not cleaned up. If human waste is spilled, it will need to be treated as a biological hazard of untreated sewage and will need to be cleaned up in accordance with Larimer County Health Department Guidance. The toilets will be staked in a way to prevent tipping on a dirt surface and located at least 50 feet from a drainage course or inlet. If the site cannot accommodate a portable toilet on dirt, a containment pan or other secondary containment will be provided. They will also be anchored prevent from tipping. All materials shall be properly disposed of in accordance with the law. 14. Saw Cutting And Grinding – Yes – The trench work will require cutting into the City street and some of the landscape rocks will be specially cut. This project will need the use of hardened saws. Page 7 These saws generate a significant amount of dust. Watering the cutting surface to prevent airborne particulates (BMP in the City’s Fugitive Dust Manual) is required. The cutting slurry has a high content of fine particulates (Silica Dust, Metals, etc.) that is not allowed to discharge as runoff from the site. To prevent slurry from discharging offsite, contractors will use the minimum amount of water needed to prevent dust and blades from overheating (site management control). Cutting slurry will be collected via vacuum or allowed to dry out and be scraped and swept up after the cutting has finished (saw cutting). 15. Other non-stormwater discharges including construction dewatering not covered under the Construction Dewatering Discharges general permit and wash water that may potentially contribute pollutants to the MS4 – No – Based upon the geotechnical data, ground water levels indicate that it will be significantly lower (about 12 feet) than the bottom of the deepest excavation. However, if encountered, dewatering activities may be required. Groundwater has in most excavations mixed with the dirt and as they are pumped, they will add an increased velocity coming out of the out-flow end contributing to erosion and speeding the transport of the suspended sediment particles. Also, construction dewatering activities must be identified in the Erosion Control Report if they are to be infiltrated on site. If the material is anticipated to be pumped to a stormwater conveyance the proper Construction Dewatering Permit must be pulled from the State of Colorado. If pumping activities are to occur on the site, the use of rock packs on the intake end of the pump will be used and a silt bag will be used on the outflow end of the pump to reduce the silt and sediment from leaving the activity (dewatering Control Measure). If this will be under a Dewatering Permit water samples will be collected in accordance with that permit. 16. Other areas or operations where spills can occur – No – No other areas have been identified where spills may occur. Every effort will be taken to keep potential pollutants contained to the Site and kept out of the stormwater through the use of BMPs previously listed in this report and graphically represented in the corresponding plan set. CONSTRUCTION CONTROL MEASURES Silt Fences (SF): (Initial and interim phases) Used to keep silt created during construction from escaping downstream. These silt fences shall be installed to fully comply with the regulations set forth in Reference 2. Silt fence will be left in place or re-installed at the Final Phase as necessary to protect un-stabilized tributary areas as required by the City. Vehicle Tracking Control (VTC): This BMP shall be placed at the entrances / exits to the construction site. This rock tracking pad serves to eliminate as much mud as possible from the tires of vehicles entering or exiting the site to paved areas. Vehicle Tracking shall be installed to fully comply with the regulations set forth in Reference 2. Stabilized Staging Area (SSA): A layer of granular material to be spread in the area used for trailer(s), parking, storage, unloading and loading, this BMP creates a mud free surface for these activities. The SSA connects to the VTC pad and will be installed with the initial phase. Page 8 Concrete Washout Area (CWA): A BMP which is essentially a shallow excavation with a small perimeter berm to isolate concrete truck washout operations. The washout area shall be combined with a vehicle tracking control pad to control tracking of mud. Construction Fence / Construction Markers (CF/CM): Either of these BMPs can be used to identify the limits of construction. Inlet Protection (IP): (Initial phase) Inlet protection, in the form of reinforced rock berms placed in front of (but not blocking) curb inlets shall be installed to prevent clogging of the existing storm inlets. Inlet protection shall remain in place until seeding establishes. Check Dam (CD): A check dam is a 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. 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. Inlet protection shall remain in place until seeding establishes. Diversion Ditch (DD): A small ditch used to collect and direct runoff away from construction activities or adjoining properties and into Sediment Basins. Slopes are shallow and velocities are to be non-erosive. Where velocities are causing erosion, check dams shall be installed to slow water and allow particles to settle. Sediment Basin (SB): A small, temporary version of a water quality control pond, this BMP captures sediment-laden runoff and releases it slowly, providing prolonged settling times to capture coarse and fine-grained soil particles. Inlet Protection (IP): (Interim phase) Inlet protection, in the form of reinforced rock berms placed in front of (but not blocking) curb inlets shall be installed to prevent clogging of newly constructed storm inlets. Inlet protection shall remain in place until seeding establishes. Reinforced Rock Berm for Culvert Protection (RRC): Reinforced Rock Berms will be installed at each pipe outlet upon completion of construction to mitigate the erosive impact of outfall flows. These will stay in place until forebays have been constructed. Rock Socks (RS): A bag of rocks usually used in curb and gutter to slow runoff and allow particles to settle. Erosion Control Logs (ECL): Weed free fibrous filled netting that is used to slow runoff and allow soil particles to settle out. These are placed at the back of curbs while lot construction takes place, at the toe of stockpiles, and on slopes where vegetation is being established. Sediment Basin (SB): The small temporary version of a water quality control pond that was installed in the initial condition shall be converted into the Extended Detention Basin (EDB) once grading of the pond is completed, this BMP captures sediment-laden runoff and releases it slowly, providing prolonged settling times to capture coarse and fine-grained soil particles. Page 9 Seeding and Mulching (SM): This BMP consists of drill seeding disturbed areas with grasses and crimping in straw mulch to provide immediate protection against raindrop and wind erosion and, as the grass cover becomes established, to provide long-term stabilization of exposed soils. The inlet protection features installed during the initial phase shall remain until the seeding from the final phase is established. Extended Detention Basin (EDB): is a sedimentation basin designed to detain stormwater for many hours after storm runoff ends. This BMP is similar to a detention basin used for flood control, however; the EDB uses a much smaller outlet that extends the emptying time of the more frequently occurring runoff events to facilitate pollutant removal. The EDB's 40-hour drain time for the water quality capture volume (WQCV) is recommended to remove a significant portion of total suspended solids (TSS). INSTALLATION AND REMOVAL SEQUENCE OF CONSTRUCTION MEASURES The construction control measures for this project will be divided into three sub-phases for BMP installation: initial, interim, and final. Each phase of the SWMP Plans has specific activities associated with it. Areas noted on the plans as to remain undisturbed (outside the LOC) will remain undisturbed, unless these plans are modified and approved by the City. As the methods of controlling erosion and sediment vary by phase, the steps taken will be discussed below in a phase-by-phase basis. During the initial stage, the following BMPs will be used to control erosion and sediment. They shall be “installed at the outset of construction, prior to the initial Preconstruction Meeting and any other land- disturbing activities. Initial controls are to be placed on existing grades but shall be based in part on proposed grading operations.” 1. Silt Fences 2. Vehicle Tracking Control 3. Stabilized Staging Areas 4. Concrete Washout Area 5. Construction Fence/Construction Markers 6. Inlet Protection 7. Check Dam 8. Sediment Basin 9. Diversion Ditches During the interim stage, the following BMPs will be used to control erosion and sediment. They shall be “based on proposed grades and drainage features and are installed after initial site grading.” Note that silt fences, vehicle tracking control, concrete washout area, stabilized staging area, and construction markers are also used in the interim phase, but are installed in the initial phase. Information on these BMPs is listed in the Initial section above. 1. Inlet Protection 2. Reinforced Rock Berm for Culvert Protection 3. Sediment Basin 4. Rough cut street control Page 10 5. Erosion control logs 6. Silt fence 7. Inlet protection During the final stage, the following BMPs will be used to control erosion and sediment. They shall be “based on proposed grades and drainage features and are installed after interim site grading.” Note that silt fences, inlet protection, and outlet protection will remain in place until final erosion control measures have sufficiently stabilized the disturbed areas. Vehicle tracking control, concrete washout area, stabilized staging area, and construction fence will be removed. 1. Seeding and Mulching 2. Extended Detention Basin 3. Erosion Control Blankets MAINTENANCE AND INSPECTION REQUIREMENTS A SWMP permit must be completed with the Colorado Department of Public Health and Environment (CDPHE) at the time of breaking ground on the site. The Contractor must also comply with SWMP general requirements found in Part I.B, Part I.C.1 and Part I.C.2 of the Stormwater Construction Permit. This includes, but is not limited to, identifying possible pollutants and Best Management Practices (BMPs) that will reduce or eliminate any possible water quality impacts. The SWMP must also be revised as necessary to account for weather, changes in the scope of work, field conditions not accurately reflected in the approved SWMP plans, or conditions not anticipated on the site. The SWMP (narrative and design drawings) will be kept updated under the supervision of the SWMP administrator and/or alternates (“Administrator”) to reflect any field changes and locations of the BMPs in use, related to daily construction site, activities or phasing changes. Construction is a dynamic condition and not all BMPs may be effective as shown on the approved SWMP during all phases of construction however the Administrator will make every effort to reflect these changes during the construction period. Should changes be deemed necessary, the Administrator will determine if engineering calculations and design changes are necessary. Any changes/revisions shall be made by the Colorado licensed professional engineer plan preparer. These changes could include: 1. Revisions to grading and drainage 2. Revisions to either removing temporary sediment basins/traps or reducing their size due to other BMP implementation. 3. Addition of sediment basins. 4. Diversions in a water way. 5. Removal of grading, drainage or hydraulic features not previously phased in the approved GESC/SWMP. 6. Relocation of diversion ditches to different basins 7. Any other modifications to the GESC/SWMP that potentially affect the health, safety and welfare of the public. 8. Use of different materials for BMPs from the approved details called out herein. Page 11 9. Relocation of temporary drainage features if additional BMPs need to be implemented to continue construction (i.e. crane route implementation). 10. Removal of previously approved BMPs not previously phased in the approved GESC/SWMP 11. Adjustment of BMPs during a phase of construction 12. BMP substitution with BMPs per the Rules and Regulations, current edition or previously approved BMPs in the site’s GESC/SWMP The updated SWMP (narrative and design drawings) will be located on site at all times. Administrator’s routine self‐inspections will be documented using forms, log books, and/or other documentation as determined to be necessary. Inspections shall occur EVERY 14 days, and after any actual precipitation or snowmelt event that causes surface erosion. Inspection will include observation of: 1. the construction site perimeter and discharge points (including discharges into a storm sewer system); 2. all disturbed areas; 3. areas used for material/waste storage that are exposed to precipitation; 4. other areas determined to have a significant potential for stormwater pollution, such as demolition areas or concrete washout locations, or locations where vehicles enter or leave the site; 5. erosion and sediment control measures identified in the SWMP; and 6. any other structural BMPs that may require maintenance, such as secondary containment around fuel tanks, or the condition of spill response kits. The inspection will determine if there is evidence of, or the potential for, pollutants entering the drainage system. BMPs will be reviewed to determine if they still meet the design and operational criteria in the SWMP, and if they continue to adequately control pollutants at the site. Any BMPs not operating in accordance with the SWMP will be addressed as soon as possible, immediately in most cases, to minimize the discharge of pollutants, and the SWMP will be updated. Documentation of site inspections must be maintained. The following items are to be recorded and kept with the SWMP: 1. Date of Inspection 2. Name(s) and title(s) of personnel making the inspection 3. Location(s) of sediment discharges or other pollutants from the site 4. Location(s) of BMP’s that need to be maintained 5. Location(s) of BMP’s that failed to operate as designed or proved inadequate 6. Locations(s) where additional BMP’s are needed that were not in place at the time of inspection 7. Deviations from the minimum inspection schedule 8. Descriptions of corrective action taken to remedy deficiencies that have been identified Page 12 9. 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 within Appendix E of this SWMP is 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: 1. BMP maintenance and operation 2. Stormwater contamination 3. Contacts with suppliers 4. Notes on the need for and performance of preventive maintenance and other repairs 5. Implementation of specific items in the SWMP 6. Training events (given or attended) 7. Events involving materials handling and storage 8. Contacts with regulatory agencies and personnel 9. 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. FINAL VEGETATION AND STABILIZATION Exposed dirt in areas that contain Hardscapes, Buildings, and Rock bed will be considered to be stabilized immediately upon installation and would prevent future Erosion to those areas. Those areas where sod will be installed as per design, will require soil amending in accordance with §12-132 and irrigated as a permanent feature to the project. Upon installation of those sod areas they will be considered stabilized and will prevent further Erosion to those areas. Those areas would then be under warranty. All areas to be seeded as outlined in the Final Landscape Plan, or required by the City in the disturbance of other properties, will have the area amended in accordance with §12-132 of City Municipal Code and be seeded based upon the specs called out in the landscape plan. A convince copy is provided below. All seeded areas will be crimped and mulched same day or next day after seeding in accordance with the Temporary and Permanent Seeding Details associated with this project as seen in the appendix, and in accordance with the City of Fort Collins Erosion Control Criteria. Once installed there will be no temporary irrigation system so all seeding will be monitored until the site has reached a vegetative cover (density) of 70%. It is anticipated that this site will be seeded in the spring of 2022 and will be fully established in the fall of 2022. At the point the vegetation has reached 70% density, and confirmed by the City of Fort Collins, the Page 13 warranty period for Erosion Control will begin, all stormwater infrastructure will be clean and removed of any sediment deposits and any remaining temporary Control Measures will be removed. Page 14 REFERENCES 1) City of Fort Collins Stormwater Criteria Manual, City of Fort Collins, CO, as adopted by the City Council of the City of Fort Collins, as referenced in Section 26-500 © of the City of Fort Collins Municipal Code, December 2018. 2) Urban Storm Drainage Criteria Manual, Volumes 1, 2, &3, Urban Drainage and Flood Control District, Volumes 1 & 2 – Originally Published September 1969, Updated January 2016; Volume 3 – Originally Published September 1992, Updated November 2010. 3) Web Soil Resource Report for Larimer County Area, Colorado, Natural Resources Conservation Service, United States Department of Agriculture. APPENDIX A – EROSION CONTROL PLANS Know what's below.before you dig.Call R PLANS UNDER REVIEW NOT FOR CONSTRUCTION ’ “” ’ ’ ’ “” 24" CPP (W) INV=4989.13 Know what's below.before you dig.Call R A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE PLANS UNDER REVIEW NOT FOR CONSTRUCTION 24" CPP (W) INV=4989.13 Know what's below.before you dig.Call R A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE PLANS UNDER REVIEW NOT FOR CONSTRUCTION Know what's below.before you dig.Call R A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE PLANS UNDER REVIEW NOT FOR CONSTRUCTION 15" RCP (NW) INV=5022.17 15" RCP (SE) 2" WALL THICKNESS CROWN=5023.59 INV(CALCULATED)=5022.17 (FROZEN AT TIME OF SURVEY) Know what's below.before you dig.Call R A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE PLANS UNDER REVIEW NOT FOR CONSTRUCTION Know what's below.before you dig.Call R A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE PLANS UNDER REVIEW NOT FOR CONSTRUCTION 24" CPP (W) INV=4989.13 Know what's below.before you dig.Call R A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE PLANS UNDER REVIEW NOT FOR CONSTRUCTION 24" CPP (W) INV=4989.13 Know what's below.before you dig.Call R A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE PLANS UNDER REVIEW NOT FOR CONSTRUCTION Know what's below.before you dig.Call R A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE PLANS UNDER REVIEW NOT FOR CONSTRUCTION 15" RCP (NW) INV=5022.17 15" RCP (SE) 2" WALL THICKNESS CROWN=5023.59 INV(CALCULATED)=5022.17 (FROZEN AT TIME OF SURVEY) Know what's below.before you dig.Call R A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE PLANS UNDER REVIEW NOT FOR CONSTRUCTION Know what's below.before you dig.Call R A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE PLANS UNDER REVIEW NOT FOR CONSTRUCTION 24" CPP (W) INV=4989.13 D D D Know what's below.before you dig.Call R A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE PLANS UNDER REVIEW NOT FOR CONSTRUCTION 24" CPP (W) INV=4989.13 D D D Know what's below.before you dig.Call R A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE PLANS UNDER REVIEW NOT FOR CONSTRUCTION Know what's below.before you dig.Call R A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE PLANS UNDER REVIEW NOT FOR CONSTRUCTION 15" RCP (NW) INV=5022.17 15" RCP (SE) 2" WALL THICKNESS CROWN=5023.59 INV(CALCULATED)=5022.17 (FROZEN AT TIME OF SURVEY) D Know what's below.before you dig.Call R A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE PLANS UNDER REVIEW NOT FOR CONSTRUCTION Know what's below.before you dig.Call R A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE A DEBRA DRIVECOLLEGE AVENUEPITNER DRIVE KEVIN DRIVERICK DRIVE TRILBY ROAD PORTNER DRIVECROWN R I D G E LANE PLANS UNDER REVIEW NOT FOR CONSTRUCTION 1 9613221001 KMAC HOLDINGS LLC GENERAL COMMERCIAL DISTRICT 1 9613221002 TUMBLEWEED HOLDINGS COMPANY LLC GENERAL COMMERCIAL DISTRICT 1 9613221003 TUMBLEWEED HOLDINGS COMPANY LLC GENERAL COMMERCIAL DISTRICT 1 9613221003 BUDS AND SUDS CAR WASH GENERAL COMMERCIAL DISTRICT 1 9613221004 TUMBLEWEED HOLDINGS COMPANY LLC GENERAL COMMERCIAL DISTRICT 1 9613221004 NATURAL ALTERNATIVES FOR HEALTH LLC GENERAL COMMERCIAL DISTRICT 1 9613221005 TUMBLEWEED HOLDINGS COMPANY LLC GENERAL COMMERCIAL DISTRICT 2 9613200025 SAMUDIO GUILLERMO JR/SONJA LOW DENSITY RESIDENTIAL DISTRICT 3 9613212001 CROMER CHARLENE R LOW DENSITY RESIDENTIAL DISTRICT 4 9613212002 BRACKETT CHANEL/ALEX LOW DENSITY RESIDENTIAL DISTRICT 5 9613212003 OLSON TODD / KELLY LAYLA LOW DENSITY RESIDENTIAL DISTRICT 6 9613212004 MIDDEL ENTERPRISES INC / DBA MIDDEL REALTY LOW DENSITY RESIDENTIAL DISTRICT 7 9613212005 COOPER BRIAN D LOW DENSITY RESIDENTIAL DISTRICT 8 9613212006 HAY PHILLIP E LOW DENSITY RESIDENTIAL DISTRICT 9 9613212007 AGNEW NANCYL/OTIS K LOW DENSITY RESIDENTIAL DISTRICT 10 9613219001 A AND R RENTALS LLC LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 FAUSTINO PLATON RAUL LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 MENDEZ RODOLFO LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 GARCIA PRIETO JESUS MANUEL LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 VALDEZ KARLA LYNN LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 ANDREWS PATRICIA A/ROBERT L LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 COX MISTINA LYNN LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 DEINES TRAVIS LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 RAUEN TAIT J LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 WHITE STEVE W LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 CHRISTENSEN LINCOLN LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 SANCHEZ MARIA TRINIDAD URUETA LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 DAYAN KRISTEN LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 FETROW ERNEST H/VIRGINIA S LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 RODRIGUEZ CRYSTAL LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 BAEZAVARGAS DELFINO LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 BOJORQUEZ ESTRADA ALVARO LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 HOFF JOHNATHAN LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 INFANTE JOHN R LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 DEVARGAS RODRIGUEZ LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 LUNA CHAVARRIA ANDRES LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 TORRES ELDER LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 CALDERON MARIA C LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 MERRITT JEANNE LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 KLIPPENSTEIN GREGORY LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 VALDEZ JESUS LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 APODACA SIXTO LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 DENNIS MARISSA L LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 BOHN DAVID LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 HUGHES RICHARD W LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 ORNELAS IVAN ITURRALDE LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 BELLO BLANCA E LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 NEWTON ROGER P LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 PORTER TABITHA LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 HEADY MATTHEW G LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 PULIDO NANCY PATRICIA LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 DELGADO MARIA DEL CARMEN LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 GUERRERO CARILLO JORGE LUIS LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 WILLIAMS ANNA M LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 GRAY RACHEL LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 VALDEZ MARTHA L/ROBERTA M LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 MUNOZ JUAN ANTONIO LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 FELIX SENOBIO ACOSTA LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 CISNEROS GUTIERREZ ALAM U LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 PARTIDA-DE VARGAS LETICIA LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 LOPEZ JOSE L LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 MEDELLIN SEVERO LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 GONZALES DAVID L J LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 BRYANT BONNIE LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 HAMMOND PETER FORREST LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 PORTILLO-RODRIGUEZ ANGEL LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 MARSHALL PATRICK E LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 BAUTISTA-ARIZMENDI CATALINO LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 COLE MELVIN W AND SUSAN D LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 POWELL CONNIE LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 BELTRAN GUILLERMO LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 VAUGHN SELMA J LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 CRAIG BRIAN LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 RALSTON SHAWN C LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 DEHERRERA DONETTA LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 RAMOS DIEGO MARTINEZ LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 CATLOW AMBER GAIL LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 MONCIVAIS RAUL LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 ORNELAS MANUEL/AMADA LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 RIVERA MARIBEL NAVAREZ/BRENDA LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 ALLEN WILLIAM MAURICE/RHONDA SUE LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 TYSON DONALD R LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 HERRERA-TRINIDAD JUAN ALBERTO LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 CAMERON ROBERT J LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 WENNERSTEN ERIC KEVIN LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 VALLEJO JUAN RODRIGUEZ LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 MUNOZ DURAN JUAN MAURICIO LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 FURNEY SYNTHIA K LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 PETERSON LEORA LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 LOPEZ RODOLFO JR LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 MENDOZA CHAPARRO RAUL LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 517 E TRILBY RD LOT 60 LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 DENNIS DENNY J/TANIA T LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 PORTILLO AISLINN LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 RODRIGUEZ-CANO JUAN M LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 RANGEL VASQUEZ JUAN R LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 STOER CHRISTOPHER T LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 BULLARD KIMBERLY R LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 GARCIA YESSICA FAVIOLA LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 WESTPHAL PU YONG C LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 TREVINO MATHEW S LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 KROSS KEVIN G LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 FLORES BARRERA LUIS V LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 KNIGHT JOANNE M LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 OEI JORDAN E LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 FLINT JOSEPH L LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 RIVERA JUAN RUBEN LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 LESTER ANDREA MARIE LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 COMBS ROBERT D E LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 PEKELO MARIE J LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 MENDEZ-CANO MARIA PATRICIA LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 JENSEN PAUL LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 GRINSTEAD ROBERT E/MEAGHAN R LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 ESPINOZA JOEL LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 CASTRO JONATHAN E LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 MCMASTER HEATHER LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 REYES YOLANDA/HERNANDEZ JORGE LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 MCCOLLISTER KAYLA MARIE/GARY DANIEL LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 SALDANO ESPERANZA OCHOA LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 MATEOS-MORONES JUAN C LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 EATMON KRISTEN B LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 GREG KLIPPENSTEIN LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 HERGENREDER MARK LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 VELASQUEZ MARITZA LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 RODRIGUEZ JUAN LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 ARC COMMUNITIES 2 LLC LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 GARCIA JESUS LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 VALDEZ SUSAN E V LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 HOFMANN GEORGE N LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 11 9613200014 PLEASANT GROVE LLC LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 12 9613131001 PROVINCETOWNE CONDOMINIUM LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 13 9613132022 CAMERRER RONALD HARRIS LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 13 9613132023 GUINN BRENT LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 13 9613132024 PATEL CHINTAN THAKORBHAI/HEATHER LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 13 9613132025 JOHNSON SCOTT D/SHELLEY A LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 13 9613132026 MCCLURE PATRICIA LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 13 9613132027 MATHEWS JULIANA LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 14 9613132028 ROSSMAN MICHAEL/HANNAH LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 14 9613132029 BENES JESSICA LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 14 9613132030 KNUTSON HOLLI M LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 15 9613132031 SMERUD KEVIN J/ANN M LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 15 9613132032 STALLINGS PRESTON M/HARMONY LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 15 9613132033 MILLER JOHN E/MARTHA A LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 16 9613132018 SMITH KELLY L LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 16 9613132019 HAILE RICHARD JR/DEBORAH K LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 16 9613132020 JUVAN MARRISCA A/RILEY W LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 16 9613132021 NAVEJAS JOEL/LYDIA R LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 17 9613132034 GALVIN STEVEN W/ANDREA L LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 17 9613132035 SHULTZ TRACEY LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 17 9613132036 DANISH SEHAR LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 17 9613132037 MAY REBECCA LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 18 9613132014 LAYNE CHIEKO S/WILLIAM J LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 18 9613132015 KROLL ANDREW LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 18 9613132016 GARCIA ANTONIO/ROSA ISELA LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 18 9613132017 GBS INVESTMENTS LLC LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 19 9613134038 SHARP BRANDON/ALLEN DELANEY LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 19 9613134039 DONGA VIKASKUMAR B LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 19 9613134040 MORRISON AUTUMN LOUELLA LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 20 9613132041 MODROWSKI BRIAN C/PATRICIA M LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 20 9613132042 LIEBENDORFER MARK LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 20 9613132043 CARRICK COURTNEY D LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 20 9613132044 ORTIZ VANESSA/JEFFREY LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 21 9613132076 CLOUSER ANGELA LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 21 9613132077 LOCKMAN MEREDITH DIANE LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 21 9613132078 COFER STACIE D LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 21 9613132079 NOCK EMILY LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 21 9613132080 HAMILTON MATTHEW J LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 22 9613143090 BAUER JUSTIN LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 22 9613143091 NAPELBAUM KYLE/GABARA MIMA DHEYAA AYSHOA AL LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 22 9613143092 CHUBBUCK PAUL A LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 22 9613143093 HENDERSON PAUL T LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 23 9613141094 MORITZ MALLORY LINDSEY LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 23 9613141095 SCHLEIGER JESSICA LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 23 9613141096 SMITH JEREMIE B LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 23 9613141097 DAVIDSON DAVID CHRISTOPHER/JULIE ANN LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 24 9613141098 KELLEY-GREENLEAF DAKOTA LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 24 9613141099 CABLE KAYLEE M LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 24 9613141100 LECLERC SCOTT LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 24 9613142101 STILTS URSULA LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 25 9613142102 BELL WILLIAM J LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 25 9613142103 WILLIAMS HEATHER D LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 25 9613139104 COBB MELISSA E LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 26 9613139105 PATNOI JACK S LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 26 9613139106 FRENCH ALEJANDRA LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 26 9613139107 RAY JADEN LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 26 9613139108 WYATT AMBER C LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 26 9613139109 SPITZ TIFFANY L LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 26 9613139110 HEFFERMAN BAYLAN LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 27 9613131902 PROVINCETOWNE GREEN LLLP LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 28 9613100927 CITY OF FORT COLLINS LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 29 9613200009 HAMAR DWAYNE W LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 30 9613213902 PEDCOR INVESTMENTS-2015-CLII LP LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT 31 9613213001 unknown LOW DENSITY MIXED-USE NEIGHBORHOOD DISTRICT ADJACENT PROPERTIES ID PARCEL NO.OWNER ZONING ADJACENT PROPERTIES ID PARCEL NO.OWNER ZONING ADJACENT PROPERTIES ID PARCEL NO.OWNER ZONING Know what's below.before you dig.Call R PLANS UNDER REVIEW NOT FOR CONSTRUCTION Know what's below.before you dig.Call R PLANS UNDER REVIEW NOT FOR CONSTRUCTION Know what's below.before you dig.Call R PLANS UNDER REVIEW NOT FOR CONSTRUCTION Know what's below.before you dig.Call R PLANS UNDER REVIEW NOT FOR CONSTRUCTION Know what's below.before you dig.Call R PLANS UNDER REVIEW NOT FOR CONSTRUCTION APPENDIX B – EROSION CONTROL ESCROW CALCULATION Project:Disturbed Acres:52.65 EROSION CONTROL BMPs Units Estimated Quantity Unit Price Total Price L.F. 3785.3 $1.60 $6,056.48 L.F. 200.0 $25.00 $5,000.00 L.F. 9572.8 $2.00 $19,145.60 L.F. 9572.8 $0.20 $1,914.56 L.F. 23.0 $9.00 $207.00 A.C. 0.2 $1,100.00 $209.00 L.F. 5210.6 $2.00 $10,421.20 S.Y. 926.40 $2.00 $1,852.80 E.A. 2.00 $1,000.00 $2,000.00 E.A. 3.00 $100.00 $300.00 S.Y. 20130.8 $5.00 $100,654.00 L.F. 96 $2.00 $192.00 L.F. 334.2 $20.00 $6,684.00 L.F. 97 $36.00 $3,492.00 E.A. 3 $1,000.00 $3,000.00 Sub-Total: $161,128.64 1.5 x Sub-Total: $241,692.96 Amount of security: $241,692.96 Total Acres x Price/acre: $131,625.00 $2,500.00 Sub-Total: $131,625.00 1.5 x Sub-Total: $197,437.50 Amount to Re-seed: $197,437.50 Minimum escrow amount: $1,500.00 Erosion Control Escrow:$241,692.96 “The amount of the security must be based on one and one-half times the estimate of the cost to install the approved measures, or one and one-half times the cost to re-vegetate the disturbed land to dry land grasses based upon unit cost determined by the City's Annual Revegetation and Stabilization Bid, whichever is greater. In no instance, will the amount of security be less than one thousand five hundred dollars ($1,500) for residential development or three thousand dollars ($3,000) for commercial development” Check Dam (CD) Construction Markers (CM) Final Escrow Amount Erosion Control Blanket (ECB) Reseeding Amount Silt Fence (SF) Stabilized Staging Area (SSA) Temporary Stream Crossing (TSC) Concrete Washout Area (CWA) Miniumum Escrow Amount Unit Price of Seeding per acre: Inlet Protection (IP) Reinforced Check Dam (RCD) Vehicle Tracking Control (VTC) Curb Sock (CS) Example Erosion and Sediment Control Escrow/Security Calculation for The City of Fort Collins BMP Amount Diversion Ditch (DD) RRB for Culvert Protection (RRC) Sediment Basin (SB) The Foothills Construction Fence (CF) 3/29/2022 8:49 AM K:\19002763\Project Documents\Engineering-Planning-Power and Energy\Reports\SWMP\Appendix B\Escrow APPENDIX C – COPIES OF PERMITS/APPLICATIONS APPENDIX D – STORMWATER MANAGEMENT PLAN INSPECTION LOGS STORM WATER MANAGEMENT PLAN INSPECTION TABLE BMP Name/ Desc.Date Erosion Control Measures Effective Brief Revision Description ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) 1 STORM WATER MANAGEMENT PLAN INSPECTION TABLE BMP Name/ Desc.Date Erosion Control Measures Effective Brief Revision Description ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) 1 STORM WATER MANAGEMENT PLAN INSPECTION TABLE BMP Name/ Desc.Date Erosion Control Measures Effective Brief Revision Description ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) 1 STORM WATER MANAGEMENT PLAN INSPECTION TABLE BMP Name/ Desc.Date Erosion Control Measures Effective Brief Revision Description ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) ___ Yes ____ No ____ Yes (w/Rev) 1 APPENDIX E – CONTRACTOR INSERTS APPENDIX F – REFERENCE MATERIAL 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 Commona Name Botanical Name Growth Seasonb Growth Form Seeds/ Pound Pounds of PLS/acre Alakali Soil Seed Mix Alkali sacaton Sporobolus airoides Cool Bunch 1,750,000 0.25 Basin wildrye Elymus cinereus Cool Bunch 165,000 2.5 Sodar streambank wheatgrass Agropyron riparium 'Sodar' Cool Sod 170,000 2.5 Jose tall wheatgrass Agropyron elongatum 'Jose' Cool Bunch 79,000 7.0 Arriba western wheatgrass Agropyron smithii 'Arriba' Cool Sod 110,000 5.5 Total 17.75 Fertile Loamy Soil Seed Mix Ephriam crested wheatgrass Agropyron cristatum 'Ephriam' Cool Sod 175,000 2.0 Dural hard fescue Festuca ovina 'duriuscula' Cool Bunch 565,000 1.0 Lincoln smooth brome Bromus inermis leyss 'Lincoln' Cool Sod 130,000 3.0 Sodar streambank wheatgrass Agropyron riparium 'Sodar' Cool Sod 170,000 2.5 Arriba western wheatgrass Agropyron smithii 'Arriba' Cool Sod 110,000 7.0 Total 15.5 High Water Table Soil Seed Mix Meadow foxtail Alopecurus pratensis Cool Sod 900,000 0.5 Redtop Agrostis alba Warm Open sod 5,000,000 0.25 Reed canarygrass Phalaris arundinacea Cool Sod 68,000 0.5 Lincoln smooth brome Bromus inermis leyss 'Lincoln' Cool Sod 130,000 3.0 Pathfinder switchgrass Panicum virgatum 'Pathfinder' Warm Sod 389,000 1.0 Alkar tall wheatgrass Agropyron elongatum 'Alkar' Cool Bunch 79,000 5.5 Total 10.75 Transition Turf Seed Mixc Ruebens Canadian bluegrass Poa compressa 'Ruebens' Cool Sod 2,500,000 0.5 Dural hard fescue Festuca ovina 'duriuscula' Cool Bunch 565,000 1.0 Citation perennial ryegrass Lolium perenne 'Citation' Cool Sod 247,000 3.0 Lincoln smooth brome Bromus inermis leyss 'Lincoln' Cool Sod 130,000 3.0 Total 7.5 Temporary and Permanent Seeding (TS/PS) EC-2 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 wheatgrassd Agropyron cristatum 'Ephriam' Cool Sod 175,000 1.5 Oahe Intermediate wheatgrass Agropyron intermedium 'Oahe' Cool Sod 115,000 5.5 Vaughn sideoats gramae Bouteloua curtipendula 'Vaughn' Warm Sod 191,000 2.0 Lincoln smooth brome Bromus inermis leyss 'Lincoln' Cool Sod 130,000 3.0 Arriba western wheatgrass Agropyron smithii 'Arriba' Cool Sod 110,000 5.5 Total 17.5 a All of the above seeding mixes and rates are based on drill seeding followed by crimped 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 Rolled Erosion Control Products (RECP) EC-6 November 2010 Urban Drainage and Flood Control District RECP-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph RECP-1. Erosion control blanket protecting the slope from erosion and providing favorable conditions for revegetation. Description Rolled Erosion Control Products (RECPs) include a variety of temporary or permanently installed manufactured products designed to control erosion and enhance vegetation establishment and survivability, particularly on slopes and in channels. For applications where natural vegetation alone will provide sufficient permanent erosion protection, temporary products such as netting, open weave textiles and a variety of erosion control blankets (ECBs) made of biodegradable natural materials (e.g., straw, coconut fiber) can be used. For applications where natural vegetation alone will not be sustainable under expected flow conditions, permanent rolled erosion control products such as turf reinforcement mats (TRMs) can be used. In particular, turf reinforcement mats are designed for discharges that exert velocities and sheer stresses that exceed the typical limits of mature natural vegetation. Appropriate Uses RECPs can be used to control erosion in conjunction with revegetation efforts, providing seedbed protection from wind and water erosion. These products are often used on disturbed areas on steep slopes, in areas with highly erosive soils, or as part of drainageway stabilization. In order to select the appropriate RECP for site conditions, it is important to have a general understanding of the general types of these products, their expected longevity, and general characteristics. The Erosion Control Technology Council (ECTC 2005) characterizes rolled erosion control products according to these categories:  Mulch control netting: A planar woven natural fiber or extruded geosynthetic mesh used as a temporary degradable rolled erosion control product to anchor loose fiber mulches.  Open weave textile: A temporary degradable rolled erosion control product composed of processed natural or polymer yarns woven into a matrix, used to provide erosion control and facilitate vegetation establishment.  Erosion control blanket (ECB): A temporary degradable rolled erosion control product composed of processed natural or polymer fibers which are mechanically, structurally or chemically bound together to form a continuous matrix to provide erosion control and facilitate vegetation establishment. ECBs can be further differentiated into rapidly degrading single-net and double-net types or slowly degrading types. Rolled Erosion Control Products Functions Erosion Control Yes Sediment Control No Site/Material Management No EC-6 Rolled Erosion Control Products (RECP) RECP-2 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3  Turf Reinforcement Mat (TRM): A rolled erosion control product composed of non-degradable synthetic fibers, filaments, nets, wire mesh, and/or other elements, processed into a permanent, three- dimensional matrix of sufficient thickness. TRMs, which may be supplemented with degradable components, are designed to impart immediate erosion protection, enhance vegetation establishment and provide long-term functionality by permanently reinforcing vegetation during and after maturation. Note: TRMs are typically used in hydraulic applications, such as high flow ditches and channels, steep slopes, stream banks, and shorelines, where erosive forces may exceed the limits of natural, unreinforced vegetation or in areas where limited vegetation establishment is anticipated. Tables RECP-1 and RECP-2 provide guidelines for selecting rolled erosion control products appropriate to site conditions and desired longevity. Table RECP-1 is for conditions where natural vegetation alone will provide permanent erosion control, whereas Table RECP-2 is for conditions where vegetation alone will not be adequately stable to provide long-term erosion protection due to flow or other conditions. Rolled Erosion Control Products (RECP) EC-6 November 2010 Urban Drainage and Flood Control District RECP-3 Urban Storm Drainage Criteria Manual Volume 3 Table RECP-1. ECTC Standard Specification for Temporary Rolled Erosion Control Products (Adapted from Erosion Control Technology Council 2005) Product Description Slope Applications* Channel Applications* Minimum Tensile Strength1 Expected Longevity Maximum Gradient C Factor2,5 Max. Shear Stress3,4,6 Mulch Control Nets 5:1 (H:V) ≤0.10 @ 5:1 0.25 lbs/ft2 (12 Pa) 5 lbs/ft (0.073 kN/m) Up to 12 months Netless Rolled Erosion Control Blankets 4:1 (H:V) ≤0.10 @ 4:1 0.5 lbs/ft2 (24 Pa) 5 lbs/ft (0.073 kN/m) Single-net Erosion Control Blankets & Open Weave Textiles 3:1 (H:V) ≤0.15 @ 3:1 1.5 lbs/ft2 (72 Pa) 50 lbs/ft (0.73 kN/m) Double-net Erosion Control Blankets 2:1 (H:V) ≤0.20 @ 2:1 1.75 lbs/ft2 (84 Pa) 75 lbs/ft (1.09 kN/m) Mulch Control Nets 5:1 (H:V) ≤0.10 @ 5:1 0.25 lbs/ft2 (12 Pa) 25 lbs/ft (0.36 kN/m) 24 months Erosion Control Blankets & Open Weave Textiles (slowly degrading) 1.5:1 (H:V) ≤0.25 @ 1.5:1 2.00 lbs/ft2 (96 Pa) 100 lbs/ft (1.45 kN/m) 24 months Erosion Control Blankets & Open Weave Textiles 1:1 (H:V) ≤0.25 @ 1:1 2.25 lbs/ft2 (108 Pa) 125 lbs/ft (1.82 kN/m) 36 months * C Factor and shear stress for mulch control nettings must be obtained with netting used in conjunction with pre-applied mulch material. (See Section 5.3 of Chapter 7 Construction BMPs for more information on the C Factor.) 1 Minimum Average Roll Values, Machine direction using ECTC Mod. ASTM D 5035. 2 C Factor calculated as ratio of soil loss from RECP protected slope (tested at specified or greater gradient, H:V) to ratio of soil loss from unprotected (control) plot in large-scale testing. 3 Required minimum shear stress RECP (unvegetated) can sustain without physical damage or excess erosion (> 12.7 mm (0.5 in) soil loss) during a 30-minute flow event in large-scale testing. 4 The permissible shear stress levels established for each performance category are based on historical experience with products characterized by Manning's roughness coefficients in the range of 0.01 - 0.05. 5 Acceptable large-scale test methods may include ASTM D 6459, or other independent testing deemed acceptable by the engineer. 6 Per the engineer’s discretion. Recommended acceptable large-scale testing protocol may include ASTM D 6460, or other independent testing deemed acceptable by the engineer. EC-6 Rolled Erosion Control Products (RECP) RECP-4 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Table RECP-2. ECTC Standard Specification for Permanent1 Rolled Erosion Control Products (Adapted from: Erosion Control Technology Council 2005) Product Type Slope Applications Channel Applications TRMs with a minimum thickness of 0.25 inches (6.35 mm) per ASTM D 6525 and UV stability of 80% per ASTM D 4355 (500 hours exposure). Maximum Gradient Maximum Shear Stress4,5 Minimum Tensile Strength2,3 0.5:1 (H:V) 6.0 lbs/ft2 (288 Pa) 125 lbs/ft (1.82 kN/m) 0.5:1 (H:V) 8.0 lbs/ft2 (384 Pa) 150 lbs/ft (2.19 kN/m) 0.5:1 (H:V) 10.0 lbs/ft2 (480 Pa) 175 lbs/ft (2.55 kN/m) 1 For TRMs containing degradable components, all property values must be obtained on the non- degradable portion of the matting alone. 2 Minimum Average Roll Values, machine direction only for tensile strength determination using ASTM D 6818 (Supersedes Mod. ASTM D 5035 for RECPs) 3 Field conditions with high loading and/or high survivability requirements may warrant the use of a TRM with a tensile strength of 44 kN/m (3,000 lb/ft) or greater. 4 Required minimum shear stress TRM (fully vegetated) can sustain without physical damage or excess erosion (> 12.7 mm (0.5 in.) soil loss) during a 30-minute flow event in large scale testing. 5 Acceptable large-scale testing protocols may include ASTM D 6460, or other independent testing deemed acceptable by the engineer. Design and Installation RECPs should be installed according to manufacturer’s specifications and guidelines. Regardless of the type of product used, it is important to ensure no gaps or voids exist under the material and that all corners of the material are secured using stakes and trenching. Continuous contact between the product and the soil is necessary to avoid failure. Never use metal stakes to secure temporary erosion control products. Often wooden stakes are used to anchor RECPs; however, wood stakes may present installation and maintenance challenges and generally take a long time to biodegrade. Some local jurisdictions have had favorable experiences using biodegradable stakes. This BMP Fact Sheet provides design details for several commonly used ECB applications, including: ECB-1 Pipe Outlet to Drainageway ECB-2 Small Ditch or Drainageway ECB-3 Outside of Drainageway Rolled Erosion Control Products (RECP) EC-6 November 2010 Urban Drainage and Flood Control District RECP-5 Urban Storm Drainage Criteria Manual Volume 3 Staking patterns are also provided in the design details according to these factors:  ECB type  Slope or channel type For other types of RECPs including TRMs, these design details are intended to serve as general guidelines for design and installation; however, engineers should adhere to manufacturer’s installation recommendations. Maintenance and Removal Inspection of erosion control blankets and other RECPs includes:  Check for general signs of erosion, including voids beneath the mat. If voids are apparent, fill the void with suitable soil and replace the erosion control blanket, following the appropriate staking pattern.  Check for damaged or loose stakes and secure loose portions of the blanket. Erosion control blankets and other RECPs that are biodegradable typically do not need to be removed after construction. If they must be removed, then an alternate soil stabilization method should be installed promptly following removal. Turf reinforcement mats, although generally resistant to biodegradation, are typically left in place as a dense vegetated cover grows in through the mat matrix. The turf reinforcement mat provides long-term stability and helps the established vegetation resist erosive forces. EC-6 Rolled Erosion Control Products (RECP) RECP-6 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Rolled Erosion Control Products (RECP) EC-6 November 2010 Urban Drainage and Flood Control District RECP-7 Urban Storm Drainage Criteria Manual Volume 3 EC-6 Rolled Erosion Control Products (RECP) RECP-8 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Rolled Erosion Control Products (RECP) EC-6 November 2010 Urban Drainage and Flood Control District RECP-9 Urban Storm Drainage Criteria Manual Volume 3 Temporary Slope Drains (TSD) EC-7 November 2010 Urban Drainage and Flood Control District SD-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph TSD-1. A temporary slope drain installed to convey runoff down a slope during construction. Photo courtesy of the City of Aurora. Description A temporary slope drain is a pipe or culvert used to convey water down a slope where there is a high potential for erosion. A drainage channel or swale at the top of the slope typically directs upgradient runoff to the pipe entrance for conveyance down the slope. The pipe outlet must be equipped with outlet protection. Appropriate Uses Use on long, steep slopes when there is a high potential of flow concentration or rill development. Design and Installation Effective use of temporary slope drains involves design of an effective collection system to direct flows to the pipe, proper sizing and anchoring of the pipe, and outlet protection. Upgradient of the temporary slope drain, a temporary drainage ditch or swale should be constructed to collect surface runoff from the drainage area and convey it to the drain entrance. The temporary slope drain must be sized to safely convey the desired flow volume. At a minimum, it should be sized to convey the 2-year, 24-hour storm. Temporary slope drains may be constructed of flexible or rigid pipe, riprap, or heavy (30 mil) plastic lining. When piping is used, it must be properly anchored by burying it with adequate cover or by using an anchor system to secure it to the ground. The discharge from the slope drain must be directed to a stabilized outlet, temporary or permanent channel, and/or sedimentation basin. See Detail TSD-1 for additional sizing and design information. Temporary Slope Drains Functions Erosion Control Yes Sediment Control No Site/Material Management No EC-7 Temporary Slope Drains (TSD) SD-2 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Maintenance and Removal Inspect the entrance for sediment accumulation and remove, as needed. Clogging as a result of sediment deposition at the entrance can lead to ponding upstream causing flooding or overtopping of the slope drain. Inspect the downstream outlet for signs of erosion and stabilize, as needed. It may also be necessary to remove accumulated sediment at the outfall. Inspect pipe anchors to ensure that they are secure. If the pipe is secured by ground cover, ensure erosion has not compromised the depth of cover. Slope drains should be removed when no longer needed or just prior to installation of permanent slope stabilization measures that cannot be installed with the slope drain in place. When slope drains are removed, the disturbed areas should be covered with topsoil, seeded, mulched or otherwise stabilized as required by the local jurisdiction. Temporary Slope Drains (TSD) EC-7 November 2010 Urban Drainage and Flood Control District SD-3 Urban Storm Drainage Criteria Manual Volume 3 EC-7 Temporary Slope Drains (TSD) SD-4 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Temporary Outlet Protection (TOP) EC-8 November 2010 Urban Drainage and Flood Control District TOP-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph TOP-1. Riprap outlet protection. Description Outlet protection helps to reduce erosion immediately downstream of a pipe, culvert, slope drain, rundown or other conveyance with concentrated, high- velocity flows. Typical outlet protection consists of riprap or rock aprons at the conveyance outlet. Appropriate Uses Outlet protection should be used when a conveyance discharges onto a disturbed area where there is potential for accelerated erosion due to concentrated flow. Outlet protection should be provided where the velocity at the culvert outlet exceeds the maximum permissible velocity of the material in the receiving channel. Note: This Fact Sheet and detail are for temporary outlet protection, outlets that are intended to be used for less than 2 years. For permanent, long-term outlet protection, see the Major Drainage chapter of Volume 1. Design and Installation Design outlet protection to handle runoff from the largest drainage area that may be contributing runoff during construction (the drainage area may change as a result of grading). Key in rock, around the entire perimeter of the apron, to a minimum depth of 6 inches for stability. Extend riprap to the height of the culvert or the normal flow depth of the downstream channel, whichever is less. Additional erosion control measures such as vegetative lining, turf reinforcement mat and/or other channel lining methods may be required downstream of the outlet protection if the channel is susceptible to erosion. See Design Detail OP-1 for additional information. Maintenance and Removal Inspect apron for damage and displaced rocks. If rocks are missing or significantly displaced, repair or replace as necessary. If rocks are continuously missing or displaced, consider increasing the size of the riprap or deeper keying of the perimeter. Remove sediment accumulated at the outlet before the outlet protection becomes buried and ineffective. When sediment accumulation is noted, check that upgradient BMPs, including inlet protection, are in effective operating condition. Outlet protection may be removed once the pipe is no longer draining an upstream area, or once the downstream area has been sufficiently stabilized. If the drainage pipe is permanent, outlet protection can be left in place; however, permanent outlet protection should be designed and constructed in accordance with the requirements of the Major Drainage chapter of Volume 2. Outlet Protection Functions Erosion Control Yes Sediment Control Moderate Site/Material Management No EC-8 Temporary Outlet Protection (TOP) TOP-2 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Temporary Outlet Protection (TOP) EC-8 November 2010 Urban Drainage and Flood Control District TOP-3 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 Terracing (TER) EC-11 November 2010 Urban Drainage and Flood Control District TER-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph TER-1. Use of a terrace to reduce erosion by controlling slope length on a long, steep slope. Photo courtesy of Douglas County. Description Terracing involves grading steep slopes into a series of relatively flat sections, or terraces, separated at intervals by steep slope segments. Terraces shorten the uninterrupted flow lengths on steep slopes, helping to reduce the development of rills and gullies. Retaining walls, gabions, cribbing, deadman anchors, rock-filled slope mattresses, and other types of soil retention systems can be used in terracing. Appropriate Uses Terracing techniques are most typically used to control erosion on slopes that are steeper than 4:1. Design and Installation Design details with notes are provided in Detail TER-1. The type, number, and spacing of terraces will depend on the slope, slope length, and other factors. The Revised Universal Soil Loss Equation (RUSLE) may be helpful in determining spacing of terraces on slopes. Terracing should be used in combination with other stabilization measures that provide cover for exposed soils such as mulching, seeding, surface roughening, or other measures. Maintenance and Removal Repair rill erosion on slopes and remove accumulated sediment, as needed. Terracing may be temporary or permanent. If terracing is temporary, the slope should be topsoiled, seeded, and mulched when the slope is graded to its final configuration and terraces are removed. Due to the steepness of the slope, once terraces are graded, erosion control blankets or other stabilization measures are typically required. If terraces are permanent, vegetation should be established on slopes and terraces as soon as practical. Terracing Functions Erosion Control Yes Sediment Control Moderate Site/Material Management No EC-11 Terracing (TER) TER-2 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-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 Sediment Basin (SB) SC-7 November 2010 Urban Drainage and Flood Control District SB-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph SB-1. Sediment basin at the toe of a slope. Photo courtesy of WWE. Description A sediment basin is a temporary pond built on a construction site to capture eroded or disturbed soil transported in storm runoff prior to discharge from the site. Sediment basins are designed to capture site runoff and slowly release it to allow time for settling of sediment prior to discharge. Sediment basins are often constructed in locations that will later be modified to serve as post-construction stormwater basins. Appropriate Uses Most large construction sites (typically greater than 2 acres) will require one or more sediment basins for effective management of construction site runoff. On linear construction projects, sediment basins may be impractical; instead, sediment traps or other combinations of BMPs may be more appropriate. Sediment basins should not be used as stand-alone sediment controls. Erosion and other sediment controls should also be implemented upstream. When feasible, the sediment basin should be installed in the same location where a permanent post- construction detention pond will be located. Design and Installation The design procedure for a sediment basin includes these steps:  Basin Storage Volume: Provide a storage volume of at least 3,600 cubic feet per acre of drainage area. To the extent practical, undisturbed and/or off-site areas should be diverted around sediment basins to prevent “clean” runoff from mixing with runoff from disturbed areas. For undisturbed areas (both on-site and off-site) that cannot be diverted around the sediment basin, provide a minimum of 500 ft3/acre of storage for undeveloped (but stable) off-site areas in addition to the 3,600 ft3/acre for disturbed areas. For stable, developed areas that cannot be diverted around the sediment basin, storage volume requirements are summarized in Table SB-1.  Basin Geometry: Design basin with a minimum length-to-width ratio of 2:1 (L:W). If this cannot be achieved because of site space constraints, baffling may be required to extend the effective distance between the inflow point(s) and the outlet to minimize short-circuiting.  Dam Embankment: It is recommended that embankment slopes be 4:1 (H:V) or flatter and no steeper than 3:1 (H:V) in any location. Sediment Basins Functions Erosion Control No Sediment Control Yes Site/Material Management No SC-7 Sediment Basin (SB) SB-2 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3  Inflow Structure: For concentrated flow entering the basin, provide energy dissipation at the point of inflow. Table SB-1. Additional Volume Requirements for Undisturbed and Developed TributaryAreas Draining through Sediment Basins Imperviousness (%) Additional Storage Volume (ft3) Per Acre of Tributary Area Undeveloped 500 10 800 20 1230 30 1600 40 2030 50 2470 60 2980 70 3560 80 4360 90 5300 100 6460  Outlet Works: The outlet pipe shall extend through the embankment at a minimum slope of 0.5 percent. Outlet works can be designed using one of the following approaches: o Perforated Riser/Plate: Follow the design criteria for Full Spectrum Detention outlets in the EDB BMP Fact Sheet provided in Chapter 4 of this manual for sizing of outlet perforations with an emptying time of approximately 72 hours. In lieu of the well-screen trash rack, pack uniformly sized 1½ - to 2-inch gravel in front of the plate. This gravel will need to be cleaned out frequently during the construction period as sediment accumulates within it. The gravel pack will need to be removed and disposed of following construction to reclaim the basin for use as a permanent detention facility. If the basin will be used as a permanent extended detention basin for the site, a well-screen trash rack will need to be installed once contributing drainage areas have been stabilized and the gravel pack and accumulated sediment have been removed. o Floating Skimmer: If a floating skimmer is used, install it using manufacturer’s recommendations. Illustration SB-1 provides an illustration of a Faircloth Skimmer Floating Outlet™, one of the more commonly used floating skimmer outlets. A skimmer should be designed to release the design volume in no less than 48 hours. The use of a floating skimmer outlet can increase the sediment capture efficiency of a basin significantly. A floating outlet continually decants cleanest water off the surface of the pond and releases cleaner water than would discharge from a perforated riser pipe or plate. Sediment Basin (SB) SC-7 November 2010 Urban Drainage and Flood Control District SB-3 Urban Storm Drainage Criteria Manual Volume 3 Illustration SB-1. Outlet structure for a temporary sediment basin - Faircloth Skimmer Floating Outlet. Illustration courtesy of J. W. Faircloth & Sons, Inc., FairclothSkimmer.com. o Outlet Protection: Outlet protection should be provided where the velocity of flow will exceed the maximum permissible velocity of the material of the waterway into which discharge occurs. This may require the use of a riprap apron at the outlet location and/or other measures to keep the waterway from eroding. o Emergency Spillway: Provide a stabilized emergency overflow spillway for rainstorms that exceed the capacity of the sediment basin volume and its outlet. Protect basin embankments from erosion and overtopping. If the sediment basin will be converted to a permanent detention basin, design and construct the emergency spillway(s) as required for the permanent facility. If the sediment basin will not become a permanent detention basin, it may be possible to substitute a heavy polyvinyl membrane or properly bedded rock cover to line the spillway and downstream embankment, depending on the height, slope, and width of the embankments. Maintenance and Removal Maintenance activities include the following: • Dredge sediment from the basin, as needed to maintain BMP effectiveness, typically when the design storage volume is no more than one-third filled with sediment. • Inspect the sediment basin embankments for stability and seepage. • Inspect the inlet and outlet of the basin, repair damage, and remove debris. Remove, clean and replace the gravel around the outlet on a regular basis to remove the accumulated sediment within it and keep the outlet functioning. • Be aware that removal of a sediment basin may require dewatering and associated permit requirements. • Do not remove a sediment basin until the upstream area has been stabilized with vegetation. SC-7 Sediment Basin (SB) SB-4 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Final disposition of the sediment basin depends on whether the basin will be converted to a permanent post-construction stormwater basin or whether the basin area will be returned to grade. For basins being converted to permanent detention basins, remove accumulated sediment and reconfigure the basin and outlet to meet the requirements of the final design for the detention facility. If the sediment basin is not to be used as a permanent detention facility, fill the excavated area with soil and stabilize with vegetation. Sediment Basin (SB) SC-7 November 2010 Urban Drainage and Flood Control District SB-5 Urban Storm Drainage Criteria Manual Volume 3 SC-7 Sediment Basin (SB) SB-6 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Sediment Basin (SB) SC-7 November 2010 Urban Drainage and Flood Control District SB-7 Urban Storm Drainage Criteria Manual Volume 3 Sediment Trap (ST) SC-8 November 2010 Urban Drainage and Flood Control District ST-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph ST-1. Sediment traps are used to collect sediment-laden runoff from disturbed area. Photo courtesy of EPA Menu of BMPs. Description Sediment traps are formed by excavating an area or by placing an earthen embankment across a low area or drainage swale. Sediment traps are designed to capture drainage from disturbed areas less than one acre and allow settling of sediment. Appropriate Uses Sediment traps can be used in combination with other layers of erosion and sediment controls to trap sediment from small drainage areas (less than one acre) or areas with localized high sediment loading. For example, sediment traps are often provided in conjunction with vehicle tracking controls and wheel wash facilities. Design and Installation A sediment trap consists of a small excavated basin with an earthen berm and a riprap outlet. The berm of the sediment trap may be constructed from the excavated material and must be compacted to 95 percent of the maximum density in accordance with ASTM D698. An overflow outlet must be provided at an elevation at least 6 inches below the top of the berm. See Detail ST-1 for additional design and installation information. Maintenance and Removal Inspect the sediment trap embankments for stability and seepage. Remove accumulated sediment as needed to maintain the effectiveness of the sediment trap, typically when the sediment depth is approximately one-half the height of the outflow embankment. Inspect the outlet for debris and damage. Repair damage to the outlet, and remove all obstructions. A sediment trap should not be removed until the upstream area is sufficiently stabilized. Upon removal of the trap, the disturbed area should be covered with topsoil and stabilized. Sediment Trap Functions Erosion Control No Sediment Control Yes Site/Material Management No SC-8 Sediment Trap (ST) ST-2 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Sediment Trap (ST) SC-8 November 2010 Urban Drainage and Flood Control District ST-3 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 Temporary Batch Plant (TBP) SM-11 November 2010 Urban Drainage and Flood Control District TBP-1 Urban Storm Drainage Criteria Manual Volume 3 Photograph TBP-1. Effective stormwater management at temporary batch plants requires implementation of multiple BMPs. Photo courtesy of California Stormwater BMP Handbook. Description Temporary batch plant management includes implementing multiple BMPs such as perimeter controls, concrete washout area, stabilized construction access, good housekeeping, and other practices designed to reduce polluted runoff from the batch plant area. Appropriate Uses Implement this BMP at temporary batch plants and identify the location of the batch plant in the SWMP. Additional permitting may be required for the operation of batch plants depending on their duration and location. Design and Installation The following lists temporary management strategies to mitigate runoff from batch plant operations:  When stockpiling materials, follow the Stockpile Management BMP.  Locate batch plants away from storm drains and natural surface waters.  A perimeter control should be installed around the temporary batch plant.  Install run-on controls where feasible.  A designated concrete washout should be located within the perimeter of the site following the procedures in the Concrete Washout Area BMP.  Follow the Good Housekeeping BMP, including proper spill containment measures, materials storage, and waste storage practices.  A stabilized construction entrance or vehicle tracking control pad should be installed at the plant entrance, in accordance with the Vehicle Tracking Control BMP. Maintenance and Removal Inspect the batch plant for proper functioning of the BMPs, with attention to material and waste storage areas, integrity of perimeter BMPs, and an effective stabilized construction entrance. Temporary Batch Plants Functions Erosion Control No Sediment Control No Site/Material Management Yes SM-11 Temporary Batch Plant (TBP) TBP-2 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 After the temporary batch plant is no longer needed, remove stockpiled materials and equipment, regrade the site as needed, and revegetate or otherwise stabilize the area. 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 United States Department of Agriculture A product of the National Cooperative Soil Survey, a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local participants Custom Soil Resource Report for Larimer County Area, ColoradoNatural Resources Conservation Service May 21, 2021 Preface Soil surveys contain information that affects land use planning in survey areas. They highlight soil limitations that affect various land uses and provide information about the properties of the soils in the survey areas. Soil surveys are designed for many different users, including farmers, ranchers, foresters, agronomists, urban planners, community officials, engineers, developers, builders, and home buyers. Also, conservationists, teachers, students, and specialists in recreation, waste disposal, and pollution control can use the surveys to help them understand, protect, or enhance the environment. Various land use regulations of Federal, State, and local governments may impose special restrictions on land use or land treatment. Soil surveys identify soil properties that are used in making various land use or land treatment decisions. The information is intended to help the land users identify and reduce the effects of soil limitations on various land uses. The landowner or user is responsible for identifying and complying with existing laws and regulations. Although soil survey information can be used for general farm, local, and wider area planning, onsite investigation is needed to supplement this information in some cases. Examples include soil quality assessments (http://www.nrcs.usda.gov/wps/ portal/nrcs/main/soils/health/) and certain conservation and engineering applications. For more detailed information, contact your local USDA Service Center (https://offices.sc.egov.usda.gov/locator/app?agency=nrcs) or your NRCS State Soil Scientist (http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/contactus/? cid=nrcs142p2_053951). Great differences in soil properties can occur within short distances. Some soils are seasonally wet or subject to flooding. Some are too unstable to be used as a foundation for buildings or roads. Clayey or wet soils are poorly suited to use as septic tank absorption fields. A high water table makes a soil poorly suited to basements or underground installations. The National Cooperative Soil Survey is a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local agencies. The Natural Resources Conservation Service (NRCS) has leadership for the Federal part of the National Cooperative Soil Survey. Information about soils is updated periodically. Updated information is available through the NRCS Web Soil Survey, the site for official soil survey information. The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, reprisal, or because all or a part of an individual's income is derived from any public assistance program. (Not all prohibited bases apply to all programs.) Persons with disabilities who require 2 alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USDA's TARGET Center at (202) 720-2600 (voice and TDD). To file a complaint of discrimination, write to USDA, Director, Office of Civil Rights, 1400 Independence Avenue, S.W., Washington, D.C. 20250-9410 or call (800) 795-3272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportunity provider and employer. 3 Contents Preface....................................................................................................................2 How Soil Surveys Are Made..................................................................................5 Soil Map..................................................................................................................8 Soil Map................................................................................................................9 Legend................................................................................................................10 Map Unit Legend................................................................................................11 Map Unit Descriptions.........................................................................................11 Larimer County Area, Colorado......................................................................14 27—Cushman fine sandy loam, 3 to 9 percent slopes................................14 36—Fort Collins loam, 3 to 5 percent slopes..............................................15 37—Fort Collins loam, 5 to 9 percent slopes..............................................16 49—Heldt clay loam, 3 to 6 percent slopes.................................................18 53—Kim loam, 1 to 3 percent slopes..........................................................19 54—Kim loam, 3 to 5 percent slopes..........................................................20 63—Longmont clay, 0 to 3 percent slopes..................................................22 74—Nunn clay loam, 1 to 3 percent slopes.................................................23 90—Renohill clay loam, 3 to 9 percent slopes............................................24 106—Tassel sandy loam, 3 to 25 percent slopes........................................26 108—Thedalund loam, 3 to 9 percent slopes..............................................27 136—Water.................................................................................................28 Soil Information for All Uses...............................................................................29 Soil Properties and Qualities..............................................................................29 Soil Erosion Factors........................................................................................29 Wind Erodibility Group.................................................................................29 Soil Qualities and Features.............................................................................32 Hydrologic Soil Group.................................................................................33 References............................................................................................................37 4 How Soil Surveys Are Made Soil surveys are made to provide information about the soils and miscellaneous areas in a specific area. They include a description of the soils and miscellaneous areas and their location on the landscape and tables that show soil properties and limitations affecting various uses. Soil scientists observed the steepness, length, and shape of the slopes; the general pattern of drainage; the kinds of crops and native plants; and the kinds of bedrock. They observed and described many soil profiles. A soil profile is the sequence of natural layers, or horizons, in a soil. The profile extends from the surface down into the unconsolidated material in which the soil formed or from the surface down to bedrock. The unconsolidated material is devoid of roots and other living organisms and has not been changed by other biological activity. Currently, soils are mapped according to the boundaries of major land resource areas (MLRAs). MLRAs are geographically associated land resource units that share common characteristics related to physiography, geology, climate, water resources, soils, biological resources, and land uses (USDA, 2006). Soil survey areas typically consist of parts of one or more MLRA. The soils and miscellaneous areas in a survey area occur in an orderly pattern that is related to the geology, landforms, relief, climate, and natural vegetation of the area. Each kind of soil and miscellaneous area is associated with a particular kind of landform or with a segment of the landform. By observing the soils and miscellaneous areas in the survey area and relating their position to specific segments of the landform, a soil scientist develops a concept, or model, of how they were formed. Thus, during mapping, this model enables the soil scientist to predict with a considerable degree of accuracy the kind of soil or miscellaneous area at a specific location on the landscape. Commonly, individual soils on the landscape merge into one another as their characteristics gradually change. To construct an accurate soil map, however, soil scientists must determine the boundaries between the soils. They can observe only a limited number of soil profiles. Nevertheless, these observations, supplemented by an understanding of the soil-vegetation-landscape relationship, are sufficient to verify predictions of the kinds of soil in an area and to determine the boundaries. Soil scientists recorded the characteristics of the soil profiles that they studied. They noted soil color, texture, size and shape of soil aggregates, kind and amount of rock fragments, distribution of plant roots, reaction, and other features that enable them to identify soils. After describing the soils in the survey area and determining their properties, the soil scientists assigned the soils to taxonomic classes (units). Taxonomic classes are concepts. Each taxonomic class has a set of soil characteristics with precisely defined limits. The classes are used as a basis for comparison to classify soils systematically. Soil taxonomy, the system of taxonomic classification used in the United States, is based mainly on the kind and character of soil properties and the arrangement of horizons within the profile. After the soil 5 scientists classified and named the soils in the survey area, they compared the individual soils with similar soils in the same taxonomic class in other areas so that they could confirm data and assemble additional data based on experience and research. The objective of soil mapping is not to delineate pure map unit components; the objective is to separate the landscape into landforms or landform segments that have similar use and management requirements. Each map unit is defined by a unique combination of soil components and/or miscellaneous areas in predictable proportions. Some components may be highly contrasting to the other components of the map unit. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The delineation of such landforms and landform segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, onsite investigation is needed to define and locate the soils and miscellaneous areas. Soil scientists make many field observations in the process of producing a soil map. The frequency of observation is dependent upon several factors, including scale of mapping, intensity of mapping, design of map units, complexity of the landscape, and experience of the soil scientist. Observations are made to test and refine the soil-landscape model and predictions and to verify the classification of the soils at specific locations. Once the soil-landscape model is refined, a significantly smaller number of measurements of individual soil properties are made and recorded. These measurements may include field measurements, such as those for color, depth to bedrock, and texture, and laboratory measurements, such as those for content of sand, silt, clay, salt, and other components. Properties of each soil typically vary from one point to another across the landscape. Observations for map unit components are aggregated to develop ranges of characteristics for the components. The aggregated values are presented. Direct measurements do not exist for every property presented for every map unit component. Values for some properties are estimated from combinations of other properties. While a soil survey is in progress, samples of some of the soils in the area generally are collected for laboratory analyses and for engineering tests. Soil scientists interpret the data from these analyses and tests as well as the field-observed characteristics and the soil properties to determine the expected behavior of the soils under different uses. Interpretations for all of the soils are field tested through observation of the soils in different uses and under different levels of management. Some interpretations are modified to fit local conditions, and some new interpretations are developed to meet local needs. Data are assembled from other sources, such as research information, production records, and field experience of specialists. For example, data on crop yields under defined levels of management are assembled from farm records and from field or plot experiments on the same kinds of soil. Predictions about soil behavior are based not only on soil properties but also on such variables as climate and biological activity. Soil conditions are predictable over long periods of time, but they are not predictable from year to year. For example, soil scientists can predict with a fairly high degree of accuracy that a given soil will have a high water table within certain depths in most years, but they cannot predict that a high water table will always be at a specific level in the soil on a specific date. After soil scientists located and identified the significant natural bodies of soil in the survey area, they drew the boundaries of these bodies on aerial photographs and Custom Soil Resource Report 6 identified each as a specific map unit. Aerial photographs show trees, buildings, fields, roads, and rivers, all of which help in locating boundaries accurately. Custom Soil Resource Report 7 Soil Map The soil map section includes the soil map for the defined area of interest, a list of soil map units on the map and extent of each map unit, and cartographic symbols displayed on the map. Also presented are various metadata about data used to produce the map, and a description of each soil map unit. 8 9 Custom Soil Resource Report Soil Map 44821004482200448230044824004482500448260044827004482100448220044823004482400448250044826004482700493400 493500 493600 493700 493800 493900 494000 494100 494200 494300 494400 494500 493400 493500 493600 493700 493800 493900 494000 494100 494200 494300 494400 494500 40° 29' 44'' N 105° 4' 42'' W40° 29' 44'' N105° 3' 52'' W40° 29' 20'' N 105° 4' 42'' W40° 29' 20'' N 105° 3' 52'' WN Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 13N WGS84 0 250 500 1000 1500Feet 0 50 100 200 300Meters Map Scale: 1:5,350 if printed on A landscape (11" x 8.5") sheet. Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Map Unit Polygons Soil Map Unit Lines Soil Map Unit Points Special Point Features Blowout Borrow Pit Clay Spot Closed Depression Gravel Pit Gravelly Spot Landfill Lava Flow Marsh or swamp Mine or Quarry Miscellaneous Water Perennial Water Rock Outcrop Saline Spot Sandy Spot Severely Eroded Spot Sinkhole Slide or Slip Sodic Spot Spoil Area Stony Spot Very Stony Spot Wet Spot Other Special Line Features Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Larimer County Area, Colorado Survey Area Data: Version 15, Jun 9, 2020 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Aug 11, 2018—Aug 12, 2018 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Custom Soil Resource Report 10 Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI 27 Cushman fine sandy loam, 3 to 9 percent slopes 6.5 12.6% 36 Fort Collins loam, 3 to 5 percent slopes 0.9 1.8% 37 Fort Collins loam, 5 to 9 percent slopes 0.5 1.0% 49 Heldt clay loam, 3 to 6 percent slopes 9.3 17.9% 53 Kim loam, 1 to 3 percent slopes 0.0 0.0% 54 Kim loam, 3 to 5 percent slopes 1.2 2.3% 63 Longmont clay, 0 to 3 percent slopes 13.8 26.4% 74 Nunn clay loam, 1 to 3 percent slopes 0.3 0.7% 90 Renohill clay loam, 3 to 9 percent slopes 10.0 19.2% 106 Tassel sandy loam, 3 to 25 percent slopes 0.0 0.0% 108 Thedalund loam, 3 to 9 percent slopes 0.1 0.1% 136 Water 9.4 18.0% Totals for Area of Interest 52.1 100.0% Map Unit Descriptions The map units delineated on the detailed soil maps in a soil survey represent the soils or miscellaneous areas in the survey area. The map unit descriptions, along with the maps, can be used to determine the composition and properties of a unit. A map unit delineation on a soil map represents an area dominated by one or more major kinds of soil or miscellaneous areas. A map unit is identified and named according to the taxonomic classification of the dominant soils. Within a taxonomic class there are precisely defined limits for the properties of the soils. On the landscape, however, the soils are natural phenomena, and they have the characteristic variability of all natural phenomena. Thus, the range of some observed properties may extend beyond the limits defined for a taxonomic class. Areas of soils of a single taxonomic class rarely, if ever, can be mapped without including areas of other taxonomic classes. Consequently, every map unit is made up of the soils or miscellaneous areas for which it is named and some minor components that belong to taxonomic classes other than those of the major soils. Most minor soils have properties similar to those of the dominant soil or soils in the map unit, and thus they do not affect use and management. These are called Custom Soil Resource Report 11 noncontrasting, or similar, components. They may or may not be mentioned in a particular map unit description. Other minor components, however, have properties and behavioral characteristics divergent enough to affect use or to require different management. These are called contrasting, or dissimilar, components. They generally are in small areas and could not be mapped separately because of the scale used. Some small areas of strongly contrasting soils or miscellaneous areas are identified by a special symbol on the maps. If included in the database for a given area, the contrasting minor components are identified in the map unit descriptions along with some characteristics of each. A few areas of minor components may not have been observed, and consequently they are not mentioned in the descriptions, especially where the pattern was so complex that it was impractical to make enough observations to identify all the soils and miscellaneous areas on the landscape. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The objective of mapping is not to delineate pure taxonomic classes but rather to separate the landscape into landforms or landform segments that have similar use and management requirements. The delineation of such segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, however, onsite investigation is needed to define and locate the soils and miscellaneous areas. An identifying symbol precedes the map unit name in the map unit descriptions. Each description includes general facts about the unit and gives important soil properties and qualities. Soils that have profiles that are almost alike make up a soil series. Except for differences in texture of the surface layer, all the soils of a series have major horizons that are similar in composition, thickness, and arrangement. Soils of one series can differ in texture of the surface layer, slope, stoniness, salinity, degree of erosion, and other characteristics that affect their use. On the basis of such differences, a soil series is divided into soil phases. Most of the areas shown on the detailed soil maps are phases of soil series. The name of a soil phase commonly indicates a feature that affects use or management. For example, Alpha silt loam, 0 to 2 percent slopes, is a phase of the Alpha series. Some map units are made up of two or more major soils or miscellaneous areas. These map units are complexes, associations, or undifferentiated groups. A complex consists of two or more soils or miscellaneous areas in such an intricate pattern or in such small areas that they cannot be shown separately on the maps. The pattern and proportion of the soils or miscellaneous areas are somewhat similar in all areas. Alpha-Beta complex, 0 to 6 percent slopes, is an example. An association is made up of two or more geographically associated soils or miscellaneous areas that are shown as one unit on the maps. Because of present or anticipated uses of the map units in the survey area, it was not considered practical or necessary to map the soils or miscellaneous areas separately. The pattern and relative proportion of the soils or miscellaneous areas are somewhat similar. Alpha-Beta association, 0 to 2 percent slopes, is an example. An undifferentiated group is made up of two or more soils or miscellaneous areas that could be mapped individually but are mapped as one unit because similar interpretations can be made for use and management. The pattern and proportion of the soils or miscellaneous areas in a mapped area are not uniform. An area can Custom Soil Resource Report 12 be made up of only one of the major soils or miscellaneous areas, or it can be made up of all of them. Alpha and Beta soils, 0 to 2 percent slopes, is an example. Some surveys include miscellaneous areas. Such areas have little or no soil material and support little or no vegetation. Rock outcrop is an example. Custom Soil Resource Report 13 Larimer County Area, Colorado 27—Cushman fine sandy loam, 3 to 9 percent slopes Map Unit Setting National map unit symbol: jpvz Elevation: 4,800 to 5,800 feet Mean annual precipitation: 13 to 15 inches Mean annual air temperature: 48 to 50 degrees F Frost-free period: 135 to 150 days Farmland classification: Not prime farmland Map Unit Composition Cushman and similar soils:90 percent Minor components:10 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Cushman Setting Landform position (three-dimensional):Side slope Down-slope shape:Linear Across-slope shape:Linear Parent material:Material weathered from sandstone and shale Typical profile H1 - 0 to 2 inches: fine sandy loam H2 - 2 to 13 inches: clay loam, sandy clay loam, loam H2 - 2 to 13 inches: loam H2 - 2 to 13 inches: weathered bedrock H3 - 13 to 31 inches: H4 - 31 to 35 inches: Properties and qualities Slope:3 to 9 percent Depth to restrictive feature:20 to 40 inches to paralithic bedrock Drainage class:Well drained Runoff class: High Capacity of the most limiting layer to transmit water (Ksat):Moderately low to moderately high (0.06 to 0.20 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Calcium carbonate, maximum content:10 percent Maximum salinity:Nonsaline to very slightly saline (0.0 to 2.0 mmhos/cm) Available water capacity:Moderate (about 8.3 inches) Interpretive groups Land capability classification (irrigated): 6e Land capability classification (nonirrigated): 4e Hydrologic Soil Group: C Ecological site: R067XY002CO - Loamy Plains Hydric soil rating: No Custom Soil Resource Report 14 Minor Components Stoneham Percent of map unit:10 percent Hydric soil rating: No 36—Fort Collins loam, 3 to 5 percent slopes Map Unit Setting National map unit symbol: 2yqpg Elevation: 4,800 to 5,900 feet Mean annual precipitation: 13 to 15 inches Mean annual air temperature: 48 to 50 degrees F Frost-free period: 135 to 150 days Farmland classification: Prime farmland if irrigated Map Unit Composition Fort collins and similar soils:80 percent Minor components:20 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Fort Collins Setting Landform:Alluvial fans, terraces Landform position (three-dimensional):Tread Down-slope shape:Linear, convex Across-slope shape:Linear Parent material:Pleistocene or older alluvium and/or eolian deposits Typical profile Ap - 0 to 5 inches: loam Bt1 - 5 to 8 inches: clay loam Bt2 - 8 to 18 inches: clay loam Bk1 - 18 to 24 inches: loam Bk2 - 24 to 80 inches: loam Properties and qualities Slope:3 to 5 percent Depth to restrictive feature:More than 80 inches Drainage class:Well drained Runoff class: Low Capacity of the most limiting layer to transmit water (Ksat):Moderately high to high (0.20 to 2.00 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Calcium carbonate, maximum content:12 percent Maximum salinity:Nonsaline to very slightly saline (0.1 to 2.0 mmhos/cm) Available water capacity:High (about 9.1 inches) Custom Soil Resource Report 15 Interpretive groups Land capability classification (irrigated): 4e Land capability classification (nonirrigated): 4e Hydrologic Soil Group: C Ecological site: R067BY002CO - Loamy Plains Hydric soil rating: No Minor Components Table mountain Percent of map unit:15 percent Landform:Stream terraces, alluvial fans Landform position (three-dimensional):Tread Down-slope shape:Linear Across-slope shape:Linear Ecological site:R067BY036CO - Overflow Hydric soil rating: No Larim Percent of map unit:5 percent Landform:Alluvial fans Down-slope shape:Linear Across-slope shape:Linear Ecological site:R067BY063CO - Gravel Breaks Hydric soil rating: No 37—Fort Collins loam, 5 to 9 percent slopes Map Unit Setting National map unit symbol: 2yqpj Elevation: 4,800 to 5,500 feet Mean annual precipitation: 13 to 15 inches Mean annual air temperature: 48 to 50 degrees F Frost-free period: 135 to 150 days Farmland classification: Farmland of statewide importance Map Unit Composition Fort collins and similar soils:80 percent Minor components:20 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Fort Collins Setting Landform:Alluvial fans, terraces Landform position (three-dimensional):Tread Down-slope shape:Linear, convex Across-slope shape:Linear Parent material:Pleistocene or older alluvium and/or eolian deposits Custom Soil Resource Report 16 Typical profile Ap - 0 to 5 inches: loam Bt1 - 5 to 8 inches: clay loam Bt2 - 8 to 18 inches: clay loam Bk1 - 18 to 24 inches: loam Bk2 - 24 to 80 inches: loam Properties and qualities Slope:5 to 9 percent Depth to restrictive feature:More than 80 inches Drainage class:Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat):Moderately high to high (0.20 to 2.00 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Calcium carbonate, maximum content:12 percent Maximum salinity:Nonsaline to very slightly saline (0.1 to 2.0 mmhos/cm) Available water capacity:High (about 9.1 inches) Interpretive groups Land capability classification (irrigated): 6e Land capability classification (nonirrigated): 6e Hydrologic Soil Group: C Ecological site: R067BY002CO - Loamy Plains Hydric soil rating: No Minor Components Larim Percent of map unit:15 percent Landform:Alluvial fans Down-slope shape:Linear Across-slope shape:Linear Ecological site:R067BY063CO - Gravel Breaks Hydric soil rating: No Table mountain Percent of map unit:5 percent Landform:Stream terraces, alluvial fans Landform position (three-dimensional):Riser Down-slope shape:Linear Across-slope shape:Linear Ecological site:R067BY036CO - Overflow Hydric soil rating: No Custom Soil Resource Report 17 49—Heldt clay loam, 3 to 6 percent slopes Map Unit Setting National map unit symbol: 2xstb Elevation: 5,080 to 6,200 feet Mean annual precipitation: 13 to 17 inches Mean annual air temperature: 50 to 54 degrees F Frost-free period: 135 to 165 days Farmland classification: Farmland of statewide importance Map Unit Composition Heldt and similar soils:85 percent Minor components:15 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Heldt Setting Landform:Stream terraces, alluvial fans Landform position (three-dimensional):Tread Down-slope shape:Linear Across-slope shape:Linear Parent material:Fine textured alluvium derived from clayey shale Typical profile Ap - 0 to 4 inches: clay loam Bw1 - 4 to 6 inches: clay loam Bw2 - 6 to 20 inches: clay Bk - 20 to 80 inches: clay Properties and qualities Slope:3 to 6 percent Depth to restrictive feature:More than 80 inches Drainage class:Well drained Runoff class: High Capacity of the most limiting layer to transmit water (Ksat):Moderately low to moderately high (0.06 to 0.20 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Calcium carbonate, maximum content:15 percent Gypsum, maximum content:3 percent Maximum salinity:Nonsaline to very slightly saline (0.5 to 2.0 mmhos/cm) Sodium adsorption ratio, maximum:5.0 Available water capacity:Moderate (about 8.6 inches) Interpretive groups Land capability classification (irrigated): 4e Land capability classification (nonirrigated): 4e Hydrologic Soil Group: C Custom Soil Resource Report 18 Ecological site: R067BY042CO - Clayey Plains Hydric soil rating: No Minor Components Renohill Percent of map unit:8 percent Landform:Pediments, hills Landform position (two-dimensional):Backslope, footslope Landform position (three-dimensional):Side slope Down-slope shape:Linear Across-slope shape:Linear Ecological site:R067BY045CO - Shaly Plains Hydric soil rating: No Nunn Percent of map unit:7 percent Landform:Terraces, alluvial fans Landform position (three-dimensional):Tread Down-slope shape:Linear Across-slope shape:Linear Ecological site:R067BY042CO - Clayey Plains Hydric soil rating: No 53—Kim loam, 1 to 3 percent slopes Map Unit Setting National map unit symbol: jpwx Elevation: 4,800 to 5,600 feet Mean annual precipitation: 13 to 15 inches Mean annual air temperature: 48 to 50 degrees F Frost-free period: 135 to 150 days Farmland classification: Prime farmland if irrigated Map Unit Composition Kim and similar soils:90 percent Minor components:10 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Kim Setting Landform:Fans Landform position (three-dimensional):Base slope Down-slope shape:Linear Across-slope shape:Linear Parent material:Mixed alluvium Typical profile H1 - 0 to 7 inches: loam H2 - 7 to 60 inches: loam, clay loam, sandy clay loam Custom Soil Resource Report 19 H2 - 7 to 60 inches: H2 - 7 to 60 inches: Properties and qualities Slope:1 to 3 percent Depth to restrictive feature:More than 80 inches Drainage class:Well drained Runoff class: Low Capacity of the most limiting layer to transmit water (Ksat):Moderately high to high (0.60 to 2.00 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Calcium carbonate, maximum content:15 percent Maximum salinity:Nonsaline to slightly saline (0.0 to 4.0 mmhos/cm) Available water capacity:Very high (about 26.5 inches) Interpretive groups Land capability classification (irrigated): 2e Land capability classification (nonirrigated): 4e Hydrologic Soil Group: B Ecological site: R067XY002CO - Loamy Plains Hydric soil rating: No Minor Components Fort collins Percent of map unit:6 percent Hydric soil rating: No Stoneham Percent of map unit:3 percent Hydric soil rating: No Aquic haplustolls Percent of map unit:1 percent Landform:Swales Hydric soil rating: Yes 54—Kim loam, 3 to 5 percent slopes Map Unit Setting National map unit symbol: jpwy Elevation: 4,800 to 5,600 feet Mean annual precipitation: 13 to 15 inches Mean annual air temperature: 48 to 50 degrees F Frost-free period: 135 to 150 days Farmland classification: Farmland of statewide importance Map Unit Composition Kim and similar soils:90 percent Custom Soil Resource Report 20 Minor components:10 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Kim Setting Landform:Fans Landform position (three-dimensional):Base slope Down-slope shape:Linear Across-slope shape:Linear Parent material:Mixed alluvium Typical profile H1 - 0 to 7 inches: loam H2 - 7 to 60 inches: loam, clay loam, sandy clay loam H2 - 7 to 60 inches: H2 - 7 to 60 inches: Properties and qualities Slope:3 to 5 percent Depth to restrictive feature:More than 80 inches Drainage class:Well drained Runoff class: Low Capacity of the most limiting layer to transmit water (Ksat):Moderately high to high (0.60 to 2.00 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Calcium carbonate, maximum content:15 percent Maximum salinity:Nonsaline to slightly saline (0.0 to 4.0 mmhos/cm) Available water capacity:Very high (about 26.5 inches) Interpretive groups Land capability classification (irrigated): 3e Land capability classification (nonirrigated): 4e Hydrologic Soil Group: B Ecological site: R067XY002CO - Loamy Plains Hydric soil rating: No Minor Components Thedalund Percent of map unit:4 percent Hydric soil rating: No Stoneham Percent of map unit:3 percent Hydric soil rating: No Fort collins Percent of map unit:2 percent Hydric soil rating: No Aquic haplustolls Percent of map unit:1 percent Landform:Swales Hydric soil rating: Yes Custom Soil Resource Report 21 63—Longmont clay, 0 to 3 percent slopes Map Unit Setting National map unit symbol: jpx8 Elevation: 4,800 to 5,800 feet Mean annual precipitation: 13 to 15 inches Mean annual air temperature: 48 to 50 degrees F Frost-free period: 135 to 150 days Farmland classification: Prime farmland if irrigated and reclaimed of excess salts and sodium Map Unit Composition Longmont and similar soils:85 percent Minor components:15 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Longmont Setting Landform:Valleys, flood plains Landform position (three-dimensional):Base slope, tread Down-slope shape:Linear Across-slope shape:Linear Parent material:Clayey alluvium derived from shale Typical profile H1 - 0 to 60 inches: clay Properties and qualities Slope:0 to 3 percent Depth to restrictive feature:More than 80 inches Drainage class:Poorly drained Runoff class: High Capacity of the most limiting layer to transmit water (Ksat):Moderately low to moderately high (0.06 to 0.20 in/hr) Depth to water table:About 24 to 30 inches Frequency of flooding:OccasionalNone Frequency of ponding:None Calcium carbonate, maximum content:15 percent Gypsum, maximum content:5 percent Maximum salinity:Slightly saline to strongly saline (4.0 to 16.0 mmhos/cm) Sodium adsorption ratio, maximum:20.0 Available water capacity:Moderate (about 8.4 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 6w Hydrologic Soil Group: D Ecological site: R067BY035CO - Salt Meadow Hydric soil rating: No Custom Soil Resource Report 22 Minor Components Dacono Percent of map unit:5 percent Hydric soil rating: No Heldt Percent of map unit:5 percent Hydric soil rating: No Aquolls Percent of map unit:5 percent Landform:Swales Hydric soil rating: Yes 74—Nunn clay loam, 1 to 3 percent slopes Map Unit Setting National map unit symbol: 2tlpl Elevation: 3,900 to 5,840 feet Mean annual precipitation: 13 to 17 inches Mean annual air temperature: 50 to 54 degrees F Frost-free period: 135 to 160 days Farmland classification: Prime farmland if irrigated Map Unit Composition Nunn and similar soils:85 percent Minor components:15 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Nunn Setting Landform:Terraces Landform position (three-dimensional):Tread Down-slope shape:Linear Across-slope shape:Linear Parent material:Pleistocene aged alluvium and/or eolian deposits Typical profile Ap - 0 to 9 inches: clay loam Bt - 9 to 13 inches: clay loam Btk - 13 to 25 inches: clay loam Bk1 - 25 to 38 inches: clay loam Bk2 - 38 to 80 inches: clay loam Properties and qualities Slope:1 to 3 percent Depth to restrictive feature:More than 80 inches Drainage class:Well drained Runoff class: Medium Custom Soil Resource Report 23 Capacity of the most limiting layer to transmit water (Ksat):Moderately low to moderately high (0.06 to 0.20 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Calcium carbonate, maximum content:7 percent Maximum salinity:Nonsaline to very slightly saline (0.1 to 2.0 mmhos/cm) Sodium adsorption ratio, maximum:0.5 Available water capacity:High (about 9.9 inches) Interpretive groups Land capability classification (irrigated): 2e Land capability classification (nonirrigated): 3e Hydrologic Soil Group: C Ecological site: R067BY042CO - Clayey Plains Hydric soil rating: No Minor Components Heldt Percent of map unit:10 percent Landform:Terraces Landform position (three-dimensional):Tread Down-slope shape:Linear Across-slope shape:Linear Ecological site:R067BY042CO - Clayey Plains Hydric soil rating: No Satanta Percent of map unit:5 percent Landform:Terraces Landform position (three-dimensional):Tread Down-slope shape:Linear Across-slope shape:Linear Ecological site:R067BY002CO - Loamy Plains Hydric soil rating: No 90—Renohill clay loam, 3 to 9 percent slopes Map Unit Setting National map unit symbol: jpy7 Elevation: 4,800 to 5,600 feet Mean annual precipitation: 13 to 15 inches Mean annual air temperature: 48 to 50 degrees F Frost-free period: 135 to 150 days Farmland classification: Not prime farmland Map Unit Composition Renohill and similar soils:85 percent Minor components:15 percent Custom Soil Resource Report 24 Estimates are based on observations, descriptions, and transects of the mapunit. Description of Renohill Setting Landform position (three-dimensional):Side slope Down-slope shape:Linear Across-slope shape:Linear Parent material:Material weathered from sandstone and shale Typical profile H1 - 0 to 7 inches: clay loam H2 - 7 to 19 inches: clay loam, clay H2 - 7 to 19 inches: clay loam H3 - 19 to 29 inches: unweathered bedrock H4 - 29 to 33 inches: Properties and qualities Slope:3 to 9 percent Depth to restrictive feature:20 to 40 inches to paralithic bedrock Drainage class:Well drained Runoff class: Very high Capacity of the most limiting layer to transmit water (Ksat):Moderately low to moderately high (0.06 to 0.20 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Calcium carbonate, maximum content:15 percent Maximum salinity:Nonsaline to slightly saline (0.0 to 4.0 mmhos/cm) Available water capacity:Moderate (about 6.9 inches) Interpretive groups Land capability classification (irrigated): 4e Land capability classification (nonirrigated): 6e Hydrologic Soil Group: D Hydric soil rating: No Minor Components Midway Percent of map unit:6 percent Hydric soil rating: No Heldt Percent of map unit:5 percent Hydric soil rating: No Ulm Percent of map unit:4 percent Hydric soil rating: No Custom Soil Resource Report 25 106—Tassel sandy loam, 3 to 25 percent slopes Map Unit Setting National map unit symbol: jptz Elevation: 4,800 to 5,800 feet Mean annual precipitation: 13 to 15 inches Mean annual air temperature: 48 to 50 degrees F Frost-free period: 135 to 150 days Farmland classification: Not prime farmland Map Unit Composition Tassel and similar soils:90 percent Minor components:10 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Tassel Setting Landform position (three-dimensional):Side slope Down-slope shape:Linear Across-slope shape:Linear Parent material:Material weathered from sandstone Typical profile H1 - 0 to 3 inches: sandy loam H2 - 3 to 12 inches: fine sandy loam, loamy very fine sand, sandy loam H2 - 3 to 12 inches: weathered bedrock H2 - 3 to 12 inches: H3 - 12 to 16 inches: Properties and qualities Slope:3 to 25 percent Depth to restrictive feature:10 to 20 inches to paralithic bedrock Drainage class:Well drained Runoff class: Very high Capacity of the most limiting layer to transmit water (Ksat):Moderately low to moderately high (0.06 to 0.20 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Calcium carbonate, maximum content:15 percent Available water capacity:Low (about 3.8 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 6s Hydrologic Soil Group: D Hydric soil rating: No Custom Soil Resource Report 26 Minor Components Nelson Percent of map unit:10 percent Hydric soil rating: No 108—Thedalund loam, 3 to 9 percent slopes Map Unit Setting National map unit symbol: jpv1 Elevation: 4,800 to 5,600 feet Mean annual precipitation: 13 to 15 inches Mean annual air temperature: 48 to 50 degrees F Frost-free period: 135 to 150 days Farmland classification: Not prime farmland Map Unit Composition Thedalund and similar soils:90 percent Minor components:10 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Thedalund Setting Landform position (three-dimensional):Side slope Down-slope shape:Linear Across-slope shape:Linear Parent material:Material weathered from sandstone and shale Typical profile H1 - 0 to 6 inches: loam H2 - 6 to 37 inches: clay loam, loam, sandy clay loam H2 - 6 to 37 inches: weathered bedrock H2 - 6 to 37 inches: H3 - 37 to 41 inches: Properties and qualities Slope:3 to 9 percent Depth to restrictive feature:20 to 40 inches to paralithic bedrock Drainage class:Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat):Moderately low to high (0.06 to 2.00 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Calcium carbonate, maximum content:15 percent Maximum salinity:Nonsaline to moderately saline (0.0 to 8.0 mmhos/cm) Available water capacity:Very high (about 16.8 inches) Custom Soil Resource Report 27 Interpretive groups Land capability classification (irrigated): 4e Land capability classification (nonirrigated): 6e Hydrologic Soil Group: C Ecological site: R067XY002CO - Loamy Plains Hydric soil rating: No Minor Components Kim Percent of map unit:6 percent Hydric soil rating: No Renohill Percent of map unit:4 percent Hydric soil rating: No 136—Water Map Unit Composition Water:95 percent Minor components:5 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Water Setting Landform:Rivers, lakes Minor Components Aquents Percent of map unit:5 percent Landform:Marshes Down-slope shape:Linear Across-slope shape:Concave Hydric soil rating: Yes Custom Soil Resource Report 28 Soil Information for All Uses Soil Properties and Qualities The Soil Properties and Qualities section includes various soil properties and qualities displayed as thematic maps with a summary table for the soil map units in the selected area of interest. A single value or rating for each map unit is generated by aggregating the interpretive ratings of individual map unit components. This aggregation process is defined for each property or quality. Soil Erosion Factors Soil Erosion Factors are soil properties and interpretations used in evaluating the soil for potential erosion. Example soil erosion factors can include K factor for the whole soil or on a rock free basis, T factor, wind erodibility group and wind erodibility index. Wind Erodibility Group A wind erodibility group (WEG) consists of soils that have similar properties affecting their susceptibility to wind erosion in cultivated areas. The soils assigned to group 1 are the most susceptible to wind erosion, and those assigned to group 8 are the least susceptible. 29 30 Custom Soil Resource Report Map—Wind Erodibility Group 44821004482200448230044824004482500448260044827004482100448220044823004482400448250044826004482700493400 493500 493600 493700 493800 493900 494000 494100 494200 494300 494400 494500 493400 493500 493600 493700 493800 493900 494000 494100 494200 494300 494400 494500 40° 29' 44'' N 105° 4' 42'' W40° 29' 44'' N105° 3' 52'' W40° 29' 20'' N 105° 4' 42'' W40° 29' 20'' N 105° 3' 52'' WN Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 13N WGS84 0 250 500 1000 1500Feet 0 50 100 200 300Meters Map Scale: 1:5,350 if printed on A landscape (11" x 8.5") sheet. Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Rating Polygons 1 2 3 4 4L 5 6 7 8 Not rated or not available Soil Rating Lines 1 2 3 4 4L 5 6 7 8 Not rated or not available Soil Rating Points 1 2 3 4 4L 5 6 7 8 Not rated or not available Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Larimer County Area, Colorado Survey Area Data: Version 15, Jun 9, 2020 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Aug 11, 2018—Aug 12, 2018 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Custom Soil Resource Report 31 Table—Wind Erodibility Group Map unit symbol Map unit name Rating Acres in AOI Percent of AOI 27 Cushman fine sandy loam, 3 to 9 percent slopes 3 6.5 12.6% 36 Fort Collins loam, 3 to 5 percent slopes 5 0.9 1.8% 37 Fort Collins loam, 5 to 9 percent slopes 5 0.5 1.0% 49 Heldt clay loam, 3 to 6 percent slopes 6 9.3 17.9% 53 Kim loam, 1 to 3 percent slopes 4L 0.0 0.0% 54 Kim loam, 3 to 5 percent slopes 4L 1.2 2.3% 63 Longmont clay, 0 to 3 percent slopes 4 13.8 26.4% 74 Nunn clay loam, 1 to 3 percent slopes 6 0.3 0.7% 90 Renohill clay loam, 3 to 9 percent slopes 6 10.0 19.2% 106 Tassel sandy loam, 3 to 25 percent slopes 3 0.0 0.0% 108 Thedalund loam, 3 to 9 percent slopes 5 0.1 0.1% 136 Water 9.4 18.0% Totals for Area of Interest 52.1 100.0% Rating Options—Wind Erodibility Group Aggregation Method: Dominant Condition Component Percent Cutoff: None Specified Tie-break Rule: Lower Soil Qualities and Features Soil qualities are behavior and performance attributes that are not directly measured, but are inferred from observations of dynamic conditions and from soil properties. Example soil qualities include natural drainage, and frost action. Soil features are attributes that are not directly part of the soil. Example soil features include slope and depth to restrictive layer. These features can greatly impact the use and management of the soil. Custom Soil Resource Report 32 Hydrologic Soil Group Hydrologic soil groups are based on estimates of runoff potential. Soils are assigned to one of four groups according to the rate of water infiltration when the soils are not protected by vegetation, are thoroughly wet, and receive precipitation from long-duration storms. The soils in the United States are assigned to four groups (A, B, C, and D) and three dual classes (A/D, B/D, and C/D). The groups are defined as follows: Group A. Soils having a high infiltration rate (low runoff potential) when thoroughly wet. These consist mainly of deep, well drained to excessively drained sands or gravelly sands. These soils have a high rate of water transmission. Group B. Soils having a moderate infiltration rate when thoroughly wet. These consist chiefly of moderately deep or deep, moderately well drained or well drained soils that have moderately fine texture to moderately coarse texture. These soils have a moderate rate of water transmission. Group C. Soils having a slow infiltration rate when thoroughly wet. These consist chiefly of soils having a layer that impedes the downward movement of water or soils of moderately fine texture or fine texture. These soils have a slow rate of water transmission. Group D. Soils having a very slow infiltration rate (high runoff potential) when thoroughly wet. These consist chiefly of clays that have a high shrink-swell potential, soils that have a high water table, soils that have a claypan or clay layer at or near the surface, and soils that are shallow over nearly impervious material. These soils have a very slow rate of water transmission. If a soil is assigned to a dual hydrologic group (A/D, B/D, or C/D), the first letter is for drained areas and the second is for undrained areas. Only the soils that in their natural condition are in group D are assigned to dual classes. Custom Soil Resource Report 33 34 Custom Soil Resource Report Map—Hydrologic Soil Group 44821004482200448230044824004482500448260044827004482100448220044823004482400448250044826004482700493400 493500 493600 493700 493800 493900 494000 494100 494200 494300 494400 494500 493400 493500 493600 493700 493800 493900 494000 494100 494200 494300 494400 494500 40° 29' 44'' N 105° 4' 42'' W40° 29' 44'' N105° 3' 52'' W40° 29' 20'' N 105° 4' 42'' W40° 29' 20'' N 105° 3' 52'' WN Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 13N WGS84 0 250 500 1000 1500Feet 0 50 100 200 300Meters Map Scale: 1:5,350 if printed on A landscape (11" x 8.5") sheet. Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Rating Polygons A A/D B B/D C C/D D Not rated or not available Soil Rating Lines A A/D B B/D C C/D D Not rated or not available Soil Rating Points A A/D B B/D C C/D D Not rated or not available Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Larimer County Area, Colorado Survey Area Data: Version 15, Jun 9, 2020 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Aug 11, 2018—Aug 12, 2018 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Custom Soil Resource Report 35 Table—Hydrologic Soil Group Map unit symbol Map unit name Rating Acres in AOI Percent of AOI 27 Cushman fine sandy loam, 3 to 9 percent slopes C 6.5 12.6% 36 Fort Collins loam, 3 to 5 percent slopes C 0.9 1.8% 37 Fort Collins loam, 5 to 9 percent slopes C 0.5 1.0% 49 Heldt clay loam, 3 to 6 percent slopes C 9.3 17.9% 53 Kim loam, 1 to 3 percent slopes B 0.0 0.0% 54 Kim loam, 3 to 5 percent slopes B 1.2 2.3% 63 Longmont clay, 0 to 3 percent slopes D 13.8 26.4% 74 Nunn clay loam, 1 to 3 percent slopes C 0.3 0.7% 90 Renohill clay loam, 3 to 9 percent slopes D 10.0 19.2% 106 Tassel sandy loam, 3 to 25 percent slopes D 0.0 0.0% 108 Thedalund loam, 3 to 9 percent slopes C 0.1 0.1% 136 Water 9.4 18.0% Totals for Area of Interest 52.1 100.0% Rating Options—Hydrologic Soil Group Aggregation Method: Dominant Condition Component Percent Cutoff: None Specified Tie-break Rule: Higher Custom Soil Resource Report 36 References American Association of State Highway and Transportation Officials (AASHTO). 2004. Standard specifications for transportation materials and methods of sampling and testing. 24th edition. American Society for Testing and Materials (ASTM). 2005. Standard classification of soils for engineering purposes. ASTM Standard D2487-00. Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of wetlands and deep-water habitats of the United States. U.S. Fish and Wildlife Service FWS/OBS-79/31. Federal Register. July 13, 1994. Changes in hydric soils of the United States. Federal Register. September 18, 2002. Hydric soils of the United States. Hurt, G.W., and L.M. Vasilas, editors. Version 6.0, 2006. Field indicators of hydric soils in the United States. National Research Council. 1995. Wetlands: Characteristics and boundaries. Soil Survey Division Staff. 1993. Soil survey manual. Soil Conservation Service. U.S. Department of Agriculture Handbook 18. http://www.nrcs.usda.gov/wps/portal/ nrcs/detail/national/soils/?cid=nrcs142p2_054262 Soil Survey Staff. 1999. Soil taxonomy: A basic system of soil classification for making and interpreting soil surveys. 2nd edition. Natural Resources Conservation Service, U.S. Department of Agriculture Handbook 436. http:// www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053577 Soil Survey Staff. 2010. Keys to soil taxonomy. 11th edition. U.S. Department of Agriculture, Natural Resources Conservation Service. http:// www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053580 Tiner, R.W., Jr. 1985. Wetlands of Delaware. U.S. Fish and Wildlife Service and Delaware Department of Natural Resources and Environmental Control, Wetlands Section. United States Army Corps of Engineers, Environmental Laboratory. 1987. Corps of Engineers wetlands delineation manual. Waterways Experiment Station Technical Report Y-87-1. United States Department of Agriculture, Natural Resources Conservation Service. National forestry manual. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/ home/?cid=nrcs142p2_053374 United States Department of Agriculture, Natural Resources Conservation Service. National range and pasture handbook. http://www.nrcs.usda.gov/wps/portal/nrcs/ detail/national/landuse/rangepasture/?cid=stelprdb1043084 37 United States Department of Agriculture, Natural Resources Conservation Service. National soil survey handbook, title 430-VI. http://www.nrcs.usda.gov/wps/portal/ nrcs/detail/soils/scientists/?cid=nrcs142p2_054242 United States Department of Agriculture, Natural Resources Conservation Service. 2006. Land resource regions and major land resource areas of the United States, the Caribbean, and the Pacific Basin. U.S. Department of Agriculture Handbook 296. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/? cid=nrcs142p2_053624 United States Department of Agriculture, Soil Conservation Service. 1961. Land capability classification. U.S. Department of Agriculture Handbook 210. http:// www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_052290.pdf Custom Soil Resource Report 38