1515 132ND ST SE 2022-01-20 - Laserfiche WebLink

Gravel and Wire Mesh Filter- A gravel barrier placed over the top of the inlet. This struc- ture does not provide an overflow. . Use a hardware cloth or comparable wire mesh with'/. -inch openings. . Use coarse aggregate. . Provide a height 1-foot or more, 18-inches wider than inlet on all sides. . Place wire mesh over the drop inlet so that the wire extends a minimum of 1-foot beyond each side of the inlet structure. . Overlap the strips if more than one strip of mesh is necessary. . Place coarse aggregate over the wire mesh. . Provide at least a 12-inch depth of gravel over the entire inlet opening and extend at least 18-inches on all sides. Catchbasin Filters — Use inserts designed by manufacturers for construction sites. The limited sediment storage capacity increases the amount of inspection and maintenance required, which may be daily for heavy sediment loads. To reduce maintenance require- ments combine a catchbasin filter with another type of inlet protection. This type of inlet protection provides flow bypass without overflow and therefore may be a better method for inlets located along active rights -of -way. . Provides 5 cubic feet of storage. . Requires dewatering provisions. . Provides a high -flow bypass that will not clog under normal use at a construction site. . Insert the catchbasin filter in the catchbasin just below the grating. Curb Inlet Protection with Wooden Weir— Barrier formed around a curb inlet with a wooden frame and gravel. . Use wire mesh with'/. -inch openings. . Use extra strength filter cloth. . Construct a frame. . Attach the wire and filter fabric to the frame. . Pile coarse washed aggregate against wiretfabric. . Place weight on frame anchors. Block and Gravel Curb Inlet Protection — Barrier formed around a curb inlet with concrete blocks and gravel. See Figure II-4.2.9 Block and Gravel Curb Inlet Protection (p.363). 2014 Stormwater Management Manual for Western Washington Volume ll - Chapter 4 - Page 361