3214 BROADWAY BROADWAY KINECT APARTMENTS 2021-08-11

• CITY OF EVERETT STORMWATER MANAGEMENT MANUAL • treated solely by a barrier,rather than by a sediment pond, is when the area draining to the barrier • is small. 411 • Brush barriers should only be installed on contours. 411 Design and Installation Specifications • 1. Height 2 feet(minimum)to 5 feet(maximum). • 2. Width 5 feet at base(minimum)to 15 feet(maximum). • 3. Filter fabric (geotextile) may be anchored over the brush berm to enhance the filtration ability of • the barrier. Ten-ounce burlap is an adequate alternative to filter fabric. 4. Chipped site vegetation,composted mulch,or wood-based mulch(hog fuel)can be used to • construct brush barriers. • 5. A 100 percent biodegradable installation can be constructed using 10-ounce burlap held in place • by wooden stakes. • Maintenance Standards • 1. There shall be no signs of erosion or concentrated runoff under or around the barrier. If concentrated flows are bypassing the barrier, it must be expanded or augmented by toed-in filter • fabric. • 2. The dimensions of the barrier must be maintained. • 3.3.14 BMP C233: Silt Fence • Purpose • Use of a silt fence reduces the transport of coarse sediment from a construction site by providing a • temporary physical barrier to sediment and reducing the runoff velocities of overland flow. See DCSS 411 Drawing#214. • Conditions of Use • • Silt fence may be used downslope of all disturbed areas. • Silt fence is not intended to treat concentrated flows, nor is it intended to treat substantial • amounts of overland flow. Any concentrated flows must be conveyed through the drainage system to a sediment pond. The only circumstance in which overland flow can be treated solely 11 by a silt fence,rather than by a sediment pond, is when the area draining to the fence is 1 acre or less and flow rates are less than 0.5 cubic feet per second. • Silt fences should not be constructed in streams or used in V-shaped ditches. They are not an • adequate method of silt control for anything deeper than sheet or overland flow. • Design and installation Specifications S 1. Drainage area of 1 acre or less or in combination with sediment basin in a larger site. 2. Maximum slope steepness(normal [perpendicular] to fence line) 1:1. . 3. Maximum sheet or overland flow path length to the fence of 100 feet. • 4. No flows greater than 0.5 cubic feet per second shall be directed toward a silt fence. • 5. The geotextile used shall meet the following standards. All geotextile properties listed below are • minimum average roll values (i.e.,the test result for any sampled roll in a lot shall meet or exceed the values shown in Table 3.10). • • Volume ll— Construction Stormwater Pollution Prevention • 3-54 • •