557 



to as many as three flushes per spring /summer. The waterusers need the 

 improved diversion facilities to accomplish this. Existing diversions are 

 largely rock berms which are bulldozed into the river each year. The berms 

 are vulnerable to washout by freshets of even nominal magnitude. The proposed 

 solution is to construct permanent diversion facilities at each diversion with 

 the capability to regulate and monitor the diversions. To solve fish passage 

 problems, the proposed structures will have fish screens to assure downstream 

 migrants safe passage to the Salmon River and ladders to concentrate flow. 

 allowing returning adults upstream escapement to reach the upper nver 

 spawning grounds A consolidation of two closely adjacent diversions. L-7 and 

 L-7A. may also be possible. 



When Reclamation began work on water conservation demonstration projects in 

 response to the Northwest Power Planning Council's amendments to the Columbia 

 River Basin Fish and Wildlife Program, a steering committee comprised of Idaho 

 interests recommended the Lemhi Basin as a worthwhile undertaking to 

 demonstrate how a river system operation could be improved with structural 

 and/or nonstructural improvements. Reclamation approached the Lemhi Soil 

 Conservation District in February 1992 with the result that agreements were 

 initiated. The waterusers want technical assistance to layout, design, fund, 

 and construct the permanent diversion structures that will provide for the 

 operation of Lemhi River waters for the benefit of both fisheries and 

 irrigation. The Lemhi River Basin was also selected as a "model watershed" 

 project under the Council's program. The proposed diversion and passage 

 facilities will provide the improved access to upstream habitats necessary to 

 achieve the production increases expected from the watershed improvements. 



Washington- -Yakima River Basin (Tributary to the Columbia River) 



The Yakima River reach involved extends from the confluence of the Naches 

 River at River Mile 116.3 downstream to Sunnyside Dam at River Mile 103.8 and 

 is located near the city of Yakima. The objectives of the study are to 

 identify a solution to river fluctuations downstream of Sunnyside Diversion 

 Dam and to have water available to react to critical streamflow situations 

 below the diversion dam. For a number of years the Yakima Project has tried 

 to operate the Yakima River system to deliver 7000 cfs to irrigators and have 

 200 cfs or some other target flow going past the lowest regulated diversion 

 (Sunnyside). The closest regulated storage is 16 hours travel time from 

 Sunnyside Dam. More than 50 entities divert water from the Yakima River 

 system below the reservoirs, with only five placing orders for changes in 

 their diversion amounts. As a result, it is only by coincidence that the 

 target flow is met. Usually the flow is exceeded, but occasionally shortfalls 

 occur. In the worst case, there is no flow in the river below the diversion, 

 the diversion to Sunnyside is not met. and the diversion dam pool is severely 

 depleted. The study objectives are to (1) identify the potential to regulate 

 flows. (2) obtain additional water for streamflow. and (3) develop a plan of 

 operations to make the streamflow more uniform. 



When Reclamation began work on water conservation demonstration projects in 

 response to NPPC amendments to the Columbia River Basin Fish and Wildlife 

 Program, a steering committee comprised of Washington State resources 



17 



