| OCR Text |
Show Flows in the entire 42 miles of river between Hades Creek and Duchesne would be reduced, under Unit operation, during the late irrigation ( late summer) season. The reduction would be small in the stream above Rock Creek. Flow losses below Rock Creek would be greater and the reduction would amount to about a 59- perceat loss of flow. However, a flow of about 100 c. f. s. would remain. Bureau of Reclamation streamflow analyses indicate that since flow reductions would be small, any reduction in fish production that might occur should not be significant in the river between Hades Creek and Knight Diversion Dam. About 10 miles of this stream section is rated Class II, about 31 miles is rated Class III, and 1 mile is rated Class IV. The severe reduction of flow during the winter below Knight Diversion Dam would be expected to significantly reduce the capacity of approximately 7 miles of the Class III water to support fish. The classification of the stream section would be expected to be lowered to Class IV or below. Rock Creek The proposed Upper Stillwater Damsite would be located on Rock Creek, 1 mile above the confluence with South Fork Rock Creek, 2.3 miles above the U. S. G. S. Gaging Station No. 9- 2780, and 8 miles above the U. S. G. S. Gaging Station No. 9- 2790. Upper Stillwater Reservoir would provida storage and regulation for the flows of Rock Creek and the South Fork of Rock Creek for diversion to Strawberry Aqueduct. Flows not required for fish or for Rock Creek and Duchesne River irrigation demands would be stored in the reservoir or diverted to the aqueduct. About 3,500 acre- feet of water in Upper Stillwater Reservoir would be utilized to maintain a minimum flow of 25 c. f. s. ( or natural flow if less) measured at the northern boundary of the Indian Reservation about 8 miles downstream. This is the joint recommendation of Bureau of Sport Fisheries and Wildlife, Utah Division of Wildlife Resources, and the Ute Indian Tribe, and would require an average release at the dam of about 8 second- feet. The daily fluctuation in flow would range between 5 and 11 c. f. s. 302 |
