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August 2005 Page 2.5 New York Standards and Specifications For Erosion and Sediment Control The following text relates to the planning flow charts on pages 2.6, 2.7 and 2.8. In the erosion and sediment control process, site designs must be prepared to address erosion control and then sediment control. Erosion control is accomplished by controlling runoff and then stabilizing soil. After erosion control has been planned, sediment control can then be developed. Step 1: Identify Control Methods—Three basic methods are used to control soil movement on construction sites: runoff control, soil stabilization, and sediment control. CONTROLLING EROSION SHALL BE THE FIRST LINE OF DEFENSE. Runoff control and soil stabilization can be used to control erosion. Controlling erosion is very effective for small-disturbed areas such as single lots or small areas of a disturbance. Sediment control may be necessary on large developments where mass grading is planned, where it is harder or impractical to control erosion, and where sediment particles are relatively large. A minimum of cost for erosion and sediment control is usually accomplished by using a combination of vegetative and structural erosion control and sedimentation control measures. Step 2: Identify Resources and Potential Problem Areas— Resources need to be identified prior to initiating an ESC plan. These resources include, but are not limited to, receiving waters, tributaries to public water supplies, beaches and other concentrated recreational areas, wetlands, trees, vegetative buffers, steep slopes and cultural resources. Areas where erosion is to be controlled will usually fall into categories of slopes, graded areas or drainage ways. Slopes include graded rights-of-way, stockpile areas, and all cut or fill slopes. Graded areas include all stripped areas other than slopes. Drainage ways are areas where concentrations of water flow naturally or artificially, and the potential for gully erosion is high. Problem areas where sediment is to be controlled fall into categories of large or small drainage areas. Small areas are usually 1 acre or less while large areas are greater than 1 acre. Step 3: Identify Required Strategy—The third step in erosion and sediment control planning is to follow the planning matrix from the problem area to the strategy that can be taken to solve the problem. Strategies can be used individually or in combination. For example, if there is a cut slope to be protected from erosion, the strategies may be to protect the ground surface, divert water from the slope, or shorten it. Any combination of these strategies can be used. If no rainfall except that which falls on the slope has the potential to cause erosion, and if the slope is relatively short, protecting the soil surface is often all that is required to solve the problem. Step 4: Identify Control Measure Group—Once required strategies are identified, the planning flow chart leads to the group or groups of control measures that will accomplish one strategy. Control measures within each group have similar purpose, scope, application, design, criteria, standard plans, and construction specifications. Therefore, any measure within a group may solve the problem in question. Step 5: Design Specific Control Measures—The final step in erosion and sediment control planning is accomplished by completing final design. This involves applying any control measure within a group to solve the specific erosion and sediment control problem. From descriptions given to the right of each control measure in the ESC planning matrix (Table 2.1), the one measure which is most economical, practical, efficient, and adaptable to the site should be chosen. Step 6: Winter Operations—If construction activities continue during winter , access points should be enlarged and stabilized to provide for snow stockpiling. In addition, a snow management plan should be prepared with adequate storage and control of meltwater. A minimum 25 foot buffer shall be maintained from perimeter controls such as silt fence. In high resource protection areas, silt fence shall be replaced with perimeter dikes, swales, or other practices resistant to the forces of snow loads. Keep drainage structures open and free of snow and ice dams. Inspection and maintenance are necessary to ensure the function of these practices during runoff events. Once the specific control measure has been selected, the plan key symbol given in the flow chart must be placed on the erosion and sediment control site plan to show where the control measure will be used. Standardized design, plan, and construction specification sheets must then be completed for each control measure. This completes the planning for erosion control and soil stabilization as part of the total natural resource plan. STEPS IN THE SELECTION AND DESIGN OF CONTROL MEASURES ---PAGE BREAK--- February 2016 Page 2.30 New York Standards and Specifications For Erosion and Sediment Control Definition & Scope A stabilized pad of aggregate underlain with geotextile located at any point where traffic will be entering or leaving a construction site to or from a public right-of-way, street, alley, sidewalk, or parking area. The purpose of stabilized construction access is to reduce or eliminate the tracking of sediment onto public rights-of-way or streets. Conditions Where Practice Applies A stabilized construction access shall be used at all points of construction ingress and egress. Design Criteria See Figure 2.1 on page 2.31 for details. Aggregate Size: Use a matrix of 1-4 inch stone, or reclaimed or recycled concrete equivalent. Thickness: Not less than six inches. Width: 12-foot minimum but not less than the full width of points where ingress or egress occurs. 24-foot minimum if there is only one access to the site. Length: As required, but not less than 50 feet (except on a single residence lot where a 30 foot minimum would apply). Geotextile: To be placed over the entire area to be covered with aggregate. Filter cloth will not be required on a single- family residence lot. Piping of surface water under entrance shall be provided as required. If piping is impossible, a mountable berm with 5:1 slopes will be permitted. Criteria for Geotextile: The geotextile shall be woven or nonwoven fabric consisting only of continuous chain polymeric filaments or yarns of polyester. The fabric shall be inert to commonly encountered chemicals, hydro-carbons, mildew, rot resistant, and conform to the fabric properties as shown: Maintenance The access shall be maintained in a condition which will prevent tracking of sediment onto public rights-of-way or streets. This may require periodic top dressing with additional aggregate. All sediment spilled, dropped, or washed onto public rights-of-way must be removed immediately. When necessary, wheels must be cleaned to remove sediment prior to entrance onto public rights-of-way. When washing is required, it shall be done on an area stabilized with aggregate, which drains into an approved sediment- trapping device. All sediment shall be prevented from entering storm drains, ditches, or watercourses. STANDARD AND SPECIFICATIONS FOR STABILIZED CONSTRUCTION ACCESS Fabric Proper- ties3 Light Duty1 Roads Grade Sub- grade Heavy Duty2 Haul Roads Rough Graded Test Method Grab Tensile Strength (lbs) 200 220 ASTM D1682 Elongation at Failure 50 60 ASTM D1682 Mullen Burst Strength (lbs) 190 430 ASTM D3786 Puncture Strength (lbs) 40 125 ASTM D751 Modified Equivalent 40-80 40-80 US Std Sieve Opening Size CW-02215 Aggregate Depth 6 10 - 1Light Duty Road: Area sites that have been graded to subgrade and where most travel would be single axle vehicles and an occasional multi- axle truck. Acceptable materials are Trevira Spunbond 1115, Mirafi 100X, Typar 3401, or equivalent. 2Heavy Duty Road: Area sites with only rough grading, and where most travel would be multi-axle vehicles. Acceptable materials are Trevira Spunbond 1135, Mirafi 600X, or equivalent. 3Fabrics not meeting these specifications may be used only when design procedure and supporting documentation are supplied to determine ag- gregate depth and fabric strength. ---PAGE BREAK--- New York Standards and Specifications Page 2.31 February 2016 For Erosion and Sediment Control Figure 2.1 Stabilized Construction Access ---PAGE BREAK--- February 2016 Page 2.24 New York Standards and Specifications For Erosion and Sediment Control Definition & Scope A temporary excavated or above ground lined constructed pit where concrete truck mixers and equipment can be washed after their loads have been discharged, to prevent highly alkaline runoff from entering storm drainage systems or leaching into soil. Conditions Where Practice Applies Washout facilities shall be provided for every project where concrete will be poured or otherwise formed on the site. This facility will receive highly alkaline wash water from the cleaning of chutes, mixers, hoppers, vibrators, placing equipment, trowels, and screeds. Under no circumstances will wash water from these operations be allowed to enter surface waters. Design Criteria Capacity: The washout facility should be sized to contain solids, wash water, and rainfall. Wash water shall be estimated at 7 gallons per chute and 50 gallons per hopper of the concrete pump truck and/or discharging drum. The minimum size shall be 8 feet by 8 feet at the bottom and 2 feet deep. If excavated, the side slopes shall be 2 horizontal to 1 vertical. Location: Locate the facility a minimum of 100 feet from drainage swales, storm drain inlets, wetlands, streams and other surface waters. Prevent surface water from entering the structure except for the access road. Provide appropriate access with a gravel access road sloped down to the structure. Signs shall be placed to direct drivers to the facility after their load is discharged. Liner: All washout facilities will be lined to prevent leaching of liquids into the ground. The liner shall be plastic sheeting with a minimum thickness of 10 mils with no holes or tears, and anchored beyond the top of the pit with an earthen berm, sand bags, stone, or other structural appurtenance except at the access point. If pre-fabricated washouts are used they must ensure the capture and containment of the concrete wash and be sized based on the expected frequency of concrete pours. They shall be sited as noted in the location criteria. Criteria for Geotextile: The geotextile shall be woven or nonwoven fabric consisting only of continuous chain polymeric filaments or yarns of polyester. The fabric shall be inert to commonly encountered chemicals, hydro- carbons, mildew, rot resistance, and conform to the fabric properties shown below: Maintenance All concrete washout facilities shall be inspected daily. Damaged or leaking facilities shall be deactivated and repaired or replaced immediately. Accumulated material shall be removed when 75% of the storage capacity of the structure is filled. Dispose of the hardened material off-site in a construction/demolition landfill. On-site disposal may be allowed if this has been approved and accepted as part of the projects In that case, the material should be recycled as specified, or buried and covered with a minimum of 2 feet of clean compacted earthfill that is permanently stabilized to prevent erosion. The plastic liner shall be replaced with each cleaning of the washout facility. Inspect the project site frequently to ensure that no concrete discharges are taking place in non-designated areas. STANDARD AND SPECIFICATIONS FOR CONCRETE TRUCK WASHOUT Fabric Proper- ties1 Roads Grade Sub- grade Haul Roads Rough Graded Test Method Grab Tensile Strength (lbs) 200 220 ASTM D1682 Elongation at Failure 50 60 ASTM D1682 Mullen Burst Strength (lbs) 190 430 ASTM D3786 Puncture Strength (lbs) 40 125 ASTM D751 Modified Equivalent 40-80 40-80 US Std Sieve Opening Size CW-02215 1Fabrics not meeting these specifications may be used only when design procedure and supporting documentation are supplied to determine aggregate depth and fabric strength. ---PAGE BREAK--- August 2005 Page 5A.19 New York Standards and Specifications For Erosion and Sediment Control STANDARD AND SPECIFICATIONS FOR SILT FENCE Definition A temporary barrier of geotextile fabric installed on the contours across a slope used to intercept sediment laden runoff from small drainage areas of disturbed soil. Purpose The purpose of a silt fence is to reduce runoff velocity and effect deposition of transported sediment load. Limits imposed by ultraviolet stability of the fabric will dictate the maximum period the silt fence may be used (approximately one year). Conditions Where Practice Applies A silt fence may be used subject to the following conditions: 1. Maximum allowable slope contributing runoff to a silt fence placed on a slope are: Slope Maximum Steepness Length (ft.) 2:1 25 3:1 50 4:1 75 5:1 or flatter 100 2. Maximum drainage area for overland flow to a silt fence shall not exceed ¼ acre per 100 feet of fence, with maximum ponding depth of 1.5 feet behind the fence; and 3. Erosion would occur in the form of sheet erosion; and 4. There is no concentration of water flowing to the barrier. Design Criteria Design computations are not required for installations of 1 month or less. Longer installation periods should be designed for expected runoff. All silt fences shall be placed as close to the areas as possible, but at least 10 feet from the toe of a slope to allow for maintenance and roll down. The area beyond the fence must be undisturbed or stabilized. Sensitive areas to be protected by silt fence may need to be reinforced by using heavy wire fencing for added support to prevent collapse. Where ends of filter cloth come together, they shall be overlapped, folded and stapled to prevent sediment bypass. A detail of the silt fence shall be shown on the plan. See Figure 5A.8 on page 5A.21 for details. Criteria for Silt Fence Materials 1. Silt Fence Fabric: The fabric shall meet the following specifications unless otherwise approved by the appropriate erosion and sediment control plan approval authority. Such approval shall not constitute statewide acceptance. Minimum Acceptable Fabric Properties Value Test Method Grab Tensile Strength (lbs) 90 ASTM D1682 Elongation at Failure 50 ASTM D1682 ---PAGE BREAK--- August 2005 Page 5A.21 New York Standards and Specifications For Erosion and Sediment Control Figure 5A.8 Silt Fence ---PAGE BREAK--- February 2016 Page 3.14 New York Standards and Specifications For Erosion and Sediment Control STANDARD AND SPECIFICATIONS FOR EARTH DIKE Definition & Scope A temporary berm or ridge of compacted soil, located in such a manner as to channel water to a desired location. Its purpose is to direct runoff to a sediment trapping device, thereby reducing the potential for erosion and off site sedi- mentation. Earth dikes can also be used for diverting clean water away from disturbed areas. Conditions Where Practice Applies Earth dikes are often constructed across disturbed areas and around construction sites such as graded parking lots and subdivisions. The dikes shall remain in place until the dis- turbed areas are permanently stabilized. Design Criteria See Figure 3.5 on page 3.15 for details. General For drainage areas larger than 10 acres, refer to the Standard and Specifications for Diversion on page 3.9. Stabilization Stabilization of the dike shall be completed within 2 days of installation in accordance with the standard and specifica- tions for seed and straw mulch or straw mulch only if not in seeding season. The flow channel shall be stabilized as per the following criteria: Outlet Earth dikes shall have an outlet that functions with a mini- mum of erosion. Runoff shall be conveyed to a sediment trapping device until the drainage area above the dike is adequately stabi- lized. The on-site location may need to be adjusted to meet field conditions in order to utilize the most suitable outlet. Dike A Dike B Drainage Area <5 Ac 5-10 Ac Dike Height 18 in. 36 in. Dike Width 24 in. 36 in. Flow Width 4 ft. 6 ft. Flow Depth in Channel 8 in. 15 in. Side Slopes 2:1 or flatter 2:1 or flatter Grade 0.5% Min. 10% Max. 0.5% Min. 10% Max. Type of Treat- ment Channel Grade1 Flow Channel A Ac.) B (5-10 Ac.) 1 0.5-3.0% Seed & Straw Mulch Seed & Straw Mulch 2 3.1-5.0% Seed & Straw Mulch Seed and cover with RECP, sod, or lined with plastic or 2” stone 3 5.1-8.0% Seed and cover with RECP, Sod, or line with plastic or 2 in. stone Line with 4-8 in. rip-rap or, geotextile 4 8.1-10% Line with 4-8 in. rip-rap or geotextile Site Specific Design 1 In highly erodible soils, as defined by the local approving agency, refer to the next higher slope grade for type of stabilization. ---PAGE BREAK--- New York State Standards and Specifications Page 3.15 February 2016 For Erosion and Sediment Control Figure 3.5 Earth Dike Detail ---PAGE BREAK--- February 2016 Page 3.4 New York Standards and Specifications For Erosion and Sediment Control STANDARD AND SPECIFICATIONS FOR CONSTRUCTION DITCH Definition & Scope A temporary excavated drainage way to intercept sediment laden water and divert it to a sediment trapping device or to prevent runoff from entering disturbed areas by intercepting and diverting it to a stabilized outlet. Conditions Where Practice Applies Construction ditches are constructed: 1. to divert flows from entering a disturbed area. 2. intermittently across disturbed areas to shorten over- land flow distances. 3. to direct sediment laden water along the base of slopes to a trapping device. 4. to transport offsite flows across disturbed areas such as rights-of-way. Ditches collecting runoff from disturbed areas shall remain in place until the disturbed areas are permanently stabilized. Design Criteria See Figure 3.2 on page 3.6 for details. General For drainage areas larger than 10 acres, refer to the Standard and Specification for Grassed Waterways on page 3.23 and 3.24. Stabilization Stabilization of the ditch shall be completed within 2 days of installation in accordance with the appropriate standard and specifications for vegetative stabilization or stabiliza- tion with mulch as determined by the time of year. The flow channel shall be stabilized as per the following criteria: Type of Treat- ment Channel Grade1 Flow Channel A Ac.) B (5-10 Ac.) 1 0.5-3.0% Seed & Straw Mulch Seed & Straw Mulch 2 3.1-5.0% Seed & Straw Mulch Seed and cover with RECP2, Sod, or lined with plastic or 2” stone 3 5.1-8.0% Seed and cover with RECP2, Sod, or line with plastic or 2 in. stone Line with 4-8 in. rip-rap or, geo- textile 4 8.1-10% Line with 4-8 in. rip-rap or geotextile Site Specific Design 1 In highly erodible soils, as defined by the local approving agency, refer to the next higher slope grade for type of stabilization. 2 Rolled Erosion Control Product. Ditch A Ditch B Drainage Area <5 Ac 5-10 Ac Bottom Width of Flow Channel 4 ft. 6 ft. Depth of Flow Channel 1 ft. 1 ft. Side Slopes 2:1 or flatter 2:1 or flatter Grade 0.5% Min. 10% Max. 0.5% Min. 10% Max. ---PAGE BREAK--- New York State Standards and Specifications Page 3.5 February 2016 For Erosion and Sediment Control Outlet Ditch shall have an outlet that functions with a minimum of erosion, and dissipates runoff velocity prior to discharge off the site. Runoff shall be conveyed to a sediment trapping device such as a sediment trap or sediment basin until the drainage area above the ditch is adequately stabilized. The on-site location may need to be adusted to meet field conditions in order to utilize the most suitable outlet condi- tion. If a ditch is used to divert clean water flows from entering a disturbed area, a sediment trapping device may not be needed. ---PAGE BREAK--- February 2016 Page 3.6 New York Standards and Specifications For Erosion and Sediment Control Figure 3.2 Construction Ditch Detail ---PAGE BREAK--- August 2005 Page 5A.23 New York Standards and Specifications For Erosion and Sediment Control STANDARD AND SPECIFICATIONS FOR CHECK DAM Definition Small barriers or dams constructed of stone, bagged sand or gravel, or other durable material across a drainage way. Purpose To reduce erosion in a drainage channel by restricting the velocity of flow in the channel. Condition Where Practice Applies This practice is used as a temporary or emergency measure to limit erosion by reducing velocities in small open channels that are degrading or subject to erosion and where permanent stabilization is impractical due to short period of usefulness and time constraints of construction. Design Criteria Drainage Area: Maximum drainage area above the check dam shall not exceed two acres. Height: Not greater than 2 feet. Center shall be maintained 9 inches lower than abutments at natural ground elevation. Side Slopes: Shall be 2:1 or flatter. Spacing: The check dams shall be spaced as necessary in the channel so that the crest of the dam is at the elevation of the toe of the upstream dam. This spacing is equal to the height of the check dam divided by the channel slope. Therefore: S = h/s Where: S = spacing interval (ft.) h = height of check dam (ft.) s = channel slope (ft./ft.) Example: For a channel with a 4% slope and 2 ft. high stone check dams, they are spaced as follows: S = 2 ft. = 50 ft. .04 ft/ft. Stone size: Use a well graded stone matrix 2 to 9 inches in size (NYS – DOT Light Stone Fill meets these requirements). The overflow of the check dams will be stabilized to resist erosion that might be caused by the check dam. See Figure 5A.9 on page 5A.24 for details. Check dams should be anchored in the channel by a cutoff trench 1.5 ft. wide and 0.5 ft. deep and lined with filter fabric to prevent soil migration. Maintenance The check dams should be inspected after each runoff event. Correct all damage immediately. If significant erosion has occurred between structures, a liner of stone or other suitable material should be installed in that portion of the channel. Remove sediment accumulated behind the dam as needed to allow channel to drain through the stone check dam and prevent large flows from carrying sediment over the dam. Replace stones as needed to maintain the design cross section of the structures. ---PAGE BREAK--- New York Standards and Specifications Page 5A.24 August 2005 For Erosion and Sediment Control Figure 5A.9 Check Dam ---PAGE BREAK--- August 2005 Page 5A.27 New York Standards and Specifications For Erosion and Sediment Control STANDARD AND SPECIFICATIONS FOR STORM DRAIN INLET PROTECTION Definition A temporary, somewhat permeable barrier, installed around inlets in the form of a fence, berm or excavation around an opening, trapping water and thereby reducing the sediment content of sediment laden water by settling. Purpose To prevent heavily sediment laden water from entering a storm drain system through inlets. Conditions Where Practice Applies This practice shall be used where the drainage area to an inlet is disturbed, it is not possible to temporarily divert the storm drain outfall into a trapping device, and watertight blocking of inlets is not advisable. It is not to be used in place of sediment trapping devices. This may be used in conjunction with storm drain diversion to help prevent siltation of pipes installed with low slope angle. Types of Storm Drain Inlet Practices There are four specific types of storm drain inlet protection practices that vary according to their function, location, drainage area, and availability of materials: I. Excavated Drop Inlet Protection II. Fabric Drop Inlet Protection III. Stone & Block Drop Inlet Protection IV. Curb Drop Inlet Protection Design Criteria Drainage Area – The drainage area for storm drain inlets shall not exceed one acre. The crest elevations of these practices shall provide storage and minimize bypass flow. Type I – Excavated Drop Inlet Protection See details for Excavated Drop Inlet Protection in Figure 5A.11 on page 5A.29. Limit the drainage area to the inlet device to 1 acre. Excavated side slopes shall be no steeper than 2:1. The minimum depth shall be 1 foot and the maximum depth 2 feet as measured from the crest of the inlet structure. Shape the excavated basin to fit conditions with the longest dimension oriented toward the longest inflow area to provide maximum trap efficiency. The capacity of the excavated basin should be established to contain 900 cubic feet per acre of disturbed area. Weep holes, protected by fabric and stone, should be provided for draining the temporary pool. Inspect and clean the excavated basin after every storm. Sediment should be removed when 50 percent of the storage volume is achieved This material should be incorporated into the site in a stabilized manner. Type II – Fabric Drop Inlet Protection See Figure 5A.12 for details on Filter Fabric Drop Inlet Protection on page 5A.30. Limit the drainage area to 1 acre per inlet device. Land area slope immediately surrounding this device should not exceed 1 percent. The maximum height of the fabric above the inlet crest shall not exceed 1.5 feet unless reinforced. The top of the barrier should be maintained to allow overflow to drop into the drop inlet and not bypass the inlet to unprotected lower areas. Support stakes for fabric shall be a minimum of 3 feet long, spaced a maximum 3 feet apart. They should be driven close to the inlet so any overflow drops into the inlet and not on the unprotected soil. Improved performance and sediment storage volume can be obtained by excavating the area. Inspect the fabric barrier after each rain event and make repairs as needed. Remove sediment from the pool area as ---PAGE BREAK--- New York Standards and Specifications Page 5A.28 August 2005 For Erosion and Sediment Control necessary with care not to undercut or damage the filter fabric. Upon stabilization of the drainage area, remove all materials and unstable sediment and dispose of properly. Bring the adjacent area of the drop inlet to grade, smooth and compact and stabilize in the appropriate manner to the site. If straw bales are used in lieu of filter fabric, they should be placed tight with the cut edge adhering to the ground at least 3 inches below the elevation of the drop inlet. Two anchor stakes per bale shall be driven flush to bale surface. Straw bales will be replaced every 4 months until the area is stabilized. Type III – Stone and Block Drop Inlet Protection See Figure 5A.13 for details on Stone and Block Drop Inlet Protection on page 5A.31. Limit the drainage area to 1 acre at the drop inlet. The stone barrier should have a minimum height of 1 foot and a maximum height of 2 feet. Do not use mortar. The height should be limited to prevent excess ponding and bypass flow. Recess the first course of blocks at least 2 inches below the crest opening of the storm drain for lateral support. Subsequent courses can be supported laterally if needed by placing a 2x4 inch wood stud through the block openings perpendicular to the course. The bottom row should have a few blocks oriented so flow can drain through the block to dewater the basin area. The stone should be placed just below the top of the blocks on slopes of 2:1 or flatter. Place hardware cloth of wire mesh with ½ inch openings over all block openings to hold stone in place. As an optional design, the concrete blocks may be omitted and the entire structure constructed of stone, ringing the outlet (“doughnut”). The stone should be kept at a 3:1 slope toward the inlet to keep it from being washed into the inlet. A level area 1 foot wide and four inches below the crest will further prevent wash. Stone on the slope toward the inlet should be at least 3 inches in size for stability and 1 inch or smaller away from the inlet to control flow rate. The elevation of the top of the stone crest must be maintained 6 inches lower than the ground elevation down slope from the inlet to ensure that all storm flows pass over the stone into the storm drain and not past the structure. Temporary diking should be used as necessary to prevent bypass flow. The barrier should be inspected after each rain event and repairs made where needed. Remove sediment as necessary to provide for accurate storage volume for subsequent rains. Upon stabilization of contributing drainage area, remove all materials and any unstable soil and dispose of properly. Bring the disturbed area to proper grade, smooth, compact and stabilized in a manner appropriate to the site. Type IV – Curb Drop Inlet Protection See Figure 5A. 14 for details on Curb Drop Inlet Protection on page 5A.32. The drainage area should be limited to 1 acre at the drop inlet. The wire mesh must be of sufficient strength to support the filter fabric and stone with the water fully impounded against it. Stone is to be 2 inches in size and clean. The filter fabric must be of a type approved for this purpose with an equivalent opening size (EOS) of 40-85. The protective structure will be constructed to extend beyond the inlet 2 feet in both directions. Assure that storm flow does not bypass the inlet by installing temporary dikes (such as sand bags) directing flow into the inlet. Make sure that the overflow weir is stable. Traffic safety shall be integrated with the use of this practice. The structure should be inspected after every storm event. Any sediment should be removed and disposed of on the site. Any stone missing should be replaced. Check materials for proper anchorage and secure as necessary.