Laserfiche WebLink
<br />., '." ., <br /> <br />Sedime~n'et <br /> <br /> <br />ntrol <br />rotectlon <br /> <br />Ponding of stormwater around inlets in roadways under construction can cause access problems and create <br />construction difficulties (saturated subgrade soils). <br /> <br />Blocking an inlet has caused streets to flood and sediment to build up, creating a safety hazard. <br /> <br />&\~5tuirements <br /> <br />This specification covers inlet protection for controlling sedimentation into and through storm sewer inlets. <br /> <br />Inlet protection will be classified by type according to use by MnDOT standards (see details that follow). Type <br />will be as indicated herein: <br /> <br />. Type A: Inlet protection to be utilized around field inlets until permanent stabilization methods have been <br />established. Inlet protection Type A may also be utilized on pavement inlets prior to installation of curb and <br />gutter or pavement. <br /> <br />. Type B: Inlet protection will be utilized on street inlets without curb heads. <br /> <br />. Type C: Inlet protection will be utilized on street inlets with curb heads. <br /> <br />. Type D: Inlet protection to be utilized at culvert inlets until permanent stabilization methods have been estab- <br />lished. <br /> <br />. Sediment Trap: Inlet protection for median drains that re not at the lowest point (see Temporary Sedimentation <br />BasinsfTraps BMP). <br /> <br />Inlet protection should only be used in locations where sediment can be removed and temporary ponding will not <br />create a safety hazard or cause property damage. Various designs have been adapted for different conditions. <br />These individual types are shown and described in the following figures. <br /> <br />Specificaitons <br />Sandbags <br /> <br />When utilizing sand bags as part of inlet protection, use the following MnDOT specifications: <br />. Sandbags shall consist of a woven polypropylene fabric sewn together with double stitching. <br />. Overall size of the sandbag shall be at least 350 x 650 mm (14 x 26 inches). <br />The poiypropylene fabric shall meet or exceed the following: <br />. Grab tensile strength ASTM D 4632 420 N, minimum <br />. UV stability ASTM D 435570 percent Minimum. <br /> <br />Geotextile <br /> <br />The geotextile shall be MnDOT Type I (permeable fabrics) for use in wrapping subsurface drain pipe or for other <br />specified drainage applications. <br /> <br />3-114 <br /> <br />Minnesota Urban Small Sites 8MP Manual <br />