Orange County NC Website
Browse       Search
166 <br /> Key points to remember during the installation phase include installing the dip at a 30- <br /> degree downslope,tying the upper end of the dip into an adjacent bank to avoid water by- <br /> passing the dip, providing a cross-drain outslope of about 3%, and energy absorbers as <br /> described in the water bar discussion. On highly erodible soils, the broad-based dip <br /> should be armored with crushed stone or rock ballast. <br /> Water Turnouts <br /> Water turnouts can be a ditch, trench, or other conveyance used to divert stormwater <br /> runoff away from a road surface or adjacent ditch. The turnout, which can be the width of <br /> a backhoe bucket or a bulldozer blade, carries water into undisturbed areas of vegetation <br /> to both dissipate energy and disperse water flow to the forest floor. Water turnouts should <br /> intersect a ditch line at the same depth and be outsloped 1-3%. On sloping roads, turnouts <br /> should be 30-45 degrees downslope. The use of water turnouts is often dependent on <br /> gradient of the property and availability of suitable outlets. Water turnouts should be <br /> spaced at a distance to provide good road drainage thus avoiding water pooling which can <br /> lead to soil compaction, souping, or rutting. A water turnout can have a secondary <br /> application of functioning as a minor sediment trap, therefore, maintenance is important <br /> to ensure the turnout is neither subject to erosion itself from excessive runoff events or <br /> sedimentation to the point of becoming nonfunctional. As with other water control <br /> structures covered in this section,tract closure should include perennial grass <br /> seeding/mulching or volunteer vegetation growth to enhance Iong-term stability of the <br /> turnout. Most importantly, water turnouts must not empty directly into streams or other <br /> water channels (i.e., drainage ways, ditches, channalized streams, etc.) leading directly to <br /> streams and other waters of the State. <br /> Water <br /> i <br /> To <br /> divert water water away frornroad and carry it iDtO undistuvbed areas <br /> - SIIOLIICI not empty directly into adjacent <br /> or %trearn channel- <br /> • ot'turnout. spread, or run-off <br /> With LISC of rip rap, brLJSh, etc. <br /> 13 <br />