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Watersheds 1 (the undisturbed watershed above the road) and 1R (the road itself). Ditch D-1 • flows begin and terminate where road ditch flows are diverted across the road (west and east limits of Watersheds 1 and 1R) by waterbars. Runoff from the area between the road and the circumvential ditch D-2 (west side of the Topsoil Storage Pile, Watershed 2), and runoff from the southwest quadrant (western up-hill portion of the storage pile, Watershed 3) drains to circumvential ditch D-2. The runoff is diverted around, and is distributed (by energy dissipator filter fencing and tapering of the ditch) before the silt fence below, the Topsoil Storage Pile. Similarly, runoff from the area towards the east between the road and circumvential ditch D-3 (Watershed 4), and the southeast quadrant of the Topsoil Storage Pile (Watershed 5} drains to circumvential ditch D-3. The runoff is diverted around, and is distributed (by energy dissipator Fencing and tapering of the ditch) before the silt fence below, the Topsoil Storage Pile. circumvential ditches D-2 and D-3 are designed to pass the runoff from a 10-year, 24-hour storm event. Runoff from the down-hill side of the Topsoil Storage Pile (Watershed 6) is released, through a filter fence, directly into vegetative debris (filter). Culvert C-1 transfers Ditch D-4 flows across the road. Ditch D-4 collects the runoff from Watershed 7 (the natural slopes above the ditch) and Watershed 8 (the section of the dirt road from below the Topsoil Storage Pile to the Fan Bench). This runoff from the road and area outside disturbed areas is presented in this analysis to demonstrate its isolation from runoff from disturbed areas, and to size Ditch D-4 and Culvert C-1. ~ Discharges from breaks (B-1 and B-2) in the berm on the north edge of the Fan Bench and • Culverts C-3 are directed by energy dissipation and flow distribution straw bales into vegetative debris filters. bischarges from Culver C-4 are directed by energy dissipation riprap and silt fencing into a vegetative debris filter. Break B-1 in the northwest reach of the Fan Bench berm passes discharges from Ditches D-SW and Swale D-6. Ditch D-SW collects runoff from Watershed 9W and diverts it around the Fan Bench cut slope (Watershed 10). It discharges onto the Fan Bench floor, joining flows in Swale D-6 near Break B-1. Although Ditch D-SW is seeded, it is considered as an erodible channel in this review. Ditch D-6 is a broad Swale (nearly a landscape feature) midway between the tce- of-cut-slope and the fan housing structure, flowing west and thence north to the break in the berm. This broad Swale (approximated as triangular in shape with 20-foot-horizontal to 1-foot- vertical side slopes in this analysis) collects runoff from Watersheds 10 (cut slope area above the ditch) and from Watershed l l (the majority of the Fan Bench). Sheet runoff from Watershed 12 discharges through Break B-2. Culvert C-3 receives the discharge from Ditches D-SE and D-7. Ditch D-SE collects runoff from Watershed 9E. Ditch D-7 receives the discharge from Ditch D-8, and collects runoff from Watershed 13 (the natural slope above the ditch) and Watershed 14 (a graveled road between the Fan Bench and the Staging Area). Ditch D-8 collects the runoff from Watershed 15 (the natural slope above the ditch) and Watershed 16 (the western portion of the Staging Area). • (Lone Pine Gulch SAES Demonstration, 12 October 95, Page 3 of 13)