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Sediment, Organic Material, <br />and Native Seeds are <br />Captured Behind the Rolls <br />10'-2 <br />5 <br />' <br />Spacing depends <br />on Soil Type and <br />Slope Steepness <br />Straw Rolls Must be Placed <br />Along Slope Contours <br />8"-10" Dia. <br />1"x1" STAKE3"-5"LIVE STAKE <br />Adjacent Rolls <br />Shall Tightly Abut <br />3'-4' <br />NOT TO SCALE <br />6/26/18 <br />CITY OF SOUTH BENDItemRevision <br />STANDARD <br />EFFECTIVE DATE: <br />REF STD SPEC SEC <br />APPROVED/REVISED BY THE BOARD OF PUBLIC WORKS <br />STANDARDS FOR DESIGN <br />AND CONSTRUCTION <br />Kara M. Boyles, Ph.D., P.E. Date <br />FILTER SOCK 7-5 <br />7-1, 7-2 <br />June 26, 2018 <br />SECTION 7 - EARTHWORK & EROSION AND SEDIMENT CONTROL <br />INSTALLATION: <br />1. Layout a contour line on the slope. <br />2. Dig a shallow depression (about 3 to 5 inches deep), remove all debris, and lay the filter sock into it. <br />3. Secure filter sock with wooden stakes. <br />4. Terminating ends should be turned uphill (min. 6") to prevent runoff from flowing around the ends. <br />5. Seat the filter sock with foot tamped backfill on the upstream side such that water will not run under it. <br />Recommended wattle spacing by slope: <br />Slope 9" Dia.12" Dia. <br />Less than 4:1 20 ft. 40 ft. <br />2:1 to 4:1 15 ft. 30 ft. <br />2:1 or Greater 10 ft. 20 ft. <br />MAINTENANCE: <br />Sediment should be removed on a routine basis when the level of the sediment reaches <br />one half the height of the exposed filter sock. Damaged areas should be repaired <br />immediately until vegetation is established and growing through the material. <br />MATERIALS: <br />Filter socks can be from straw, rice straw, coconut husks or other approved material. The <br />netting consists of biodegradable burlap, or high density polyethylene and ethyl vinyl acetate <br />containing ultraviolet inhibitors. Straw should be certified weed free forage, by a <br />manufacturer whose principle business is wattle manufacturing. Coir (coconut fiber) can be <br />in bristle and mattress form and should be obtained from freshwater cured coconut husk. <br />DESCRIPTION: <br />Filter socks are also known as straw worms, bio-logs, straw noodles, or straw tubes. They are a sediment velocity control device made <br />of tubes of straw, rice, or coconut husk encased in an ultraviolet degradable plastic netting or 100% burlap material. <br />Filter socks may be suitable along the toe, top, face, and at grade breaks of exposed erodible slopes to shorten slope length and <br />spread runoff as sheet flow; at the end of a downward slope where it transitions to a steeper slope; along sidewalks and curbs to <br />prevent sediment from washing into gutters; around storm drains and drop inlets; down-slope of exposed soil areas; around <br />temporary material spoil and stockpiles, such as topsoil and for stream bank protection. <br />Note: Filter Socks <br />may be used in lieu <br />of silt fence if desired.