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Chapter II <br /> - Ditch Outlets <br /> Where gullies have formed below ditch relief downdrains, check <br /> dam structures will be installed as a means to slow the flow <br /> velocities. These areas are inaccessible to equipment. <br /> Construction of roads to allow equipment access would be <br /> counterproductive, creating additional disturbance and <br /> resulting in increased sedimentation. For this reason, the <br /> check dams will be created by placement of available, on-site <br /> timber. Other available on-site materials, such as large <br /> rocks, may be used as well . Work on gullies will begin in the <br /> summer of 1992 , and will proceed thereafter according to a <br /> timetable agreed upon by the operator, MLRD and the U.S.F.S. <br /> Rolling Dips <br /> During the summer of 1992, rolling dips will be installed as <br /> cross drain structures at the locations designated for <br /> Culverts F-7N, F-3N on Road F by Map II-B-7 Att. 2 Plate 6. <br /> Rolling dips will be installed to replace Culverts F-2 and F- <br /> 3 , and between Sta. 7+50 and 8+00. <br /> Waterbars <br /> Water bars may be used to direct flows on the road to the <br /> inside ditch, so as to prevent water from reaching the fill <br /> area, which would tend to create erosion gullies . <br /> On light use and access roads, and some reclaimed roads, water <br /> bars may be used in some circumstances to direct flows to the <br /> outside edge of the road. The operative considerations would <br /> be that concentration of flows to the inside ditch should be <br /> dissipated, where possible, and that the waterbars should not <br /> discharge on unstable, steep and/or poorly vegetated <br /> downslopes where excessive erosion would likely result. It <br /> should be recognized that concentrated flows create channels <br /> in the ground surface, and that some rilling and gullying <br /> along the outslope would occur where flows are managed in this <br /> fashion. Location of waterbars directing flows to the outside <br /> would be determined jointly by MLRD, the U.S. Forest Service, <br /> and the operator. <br /> Ditch Maintenance <br /> During the spring, and as necessary after storm events, the <br /> ditches will be dragged to clean them of debris and sediment. <br /> 19(b) Revised 12/91 <br />