117 



increases in polluting activities. At that point, WDE implements pollutant 

 load reductions by incorporating WLA into wastewater discharge permits, 

 developing and promoting more effective waste management practices, and 

 educating the public. 



DAMS AND DIVERSIONS 



Probably because of the Basin's relatively low gradient, the two largest dams, 

 on the Wynoochee and Skookumchuck rivers, were built relatively far upstream 

 on tributaries. While they and other smaller dams have taken a toll on fish 

 production, the Basin has escaped the major impacts associated with large- 

 scale dams as has occurred on the Columbia River. 



Wynoochee Daa 



Wynoochee Dam was built by the USACE at RM 50 of the Wynoochee River in 1972. 

 The reservoir stores about 70,000 acre-feet from a 70-square-mile drainage 

 area. The city of Aberdeen now operates and maintains the dam under the Water 

 Resources Development Act as amended in 1990 (BPA 1992). The dam controls 

 flooding, provides recreation, augments low flows, and provides municipal and 

 industrial water for the City of Aberdeen (via a diversion at RM 8.1). There 

 is currently a joint Aberdeen/Tacoma project to develop hydropower at the dam. 



Upstream Adult Passage . Chinook and coho salmon, steelhead, and sea-run 

 cutthroat trout spawned upBtream of the dam site before construction (Findlay 

 1967), and numbers of all but Chinook were estimated. 



Species Spawning escapement 



Reservoir site Upstream of reservoir 



Fall Chinook unknown unknown 



Spring Chinook unknown unknown 



Coho 1,500 



Steelhead 1,000 400 



Sea-run cutthroat trout 330 165 



The WynoochM project included a barrier dam and fish trap two miles 

 downstream of the main dam. All migrating adult salmonids are trapped and 

 trucked for release upstream of the reservoir. This facility has apparently 

 provided adequate upstream passage in most years (Ging, FWS, pers. coma. ) . 



To substitute for combined steelhead and cutthroat production lost to 

 inundation, USACE agreed to provide WDW with funds for expansion of the 

 Aberdeen Hatchery to rear 170,000 steelhead smolts, calculated to produce 

 1,700 adult steelhead, in addition to its then-existing programs. Chinook 

 salmon ware not considered in the mitigation arrangement (OSACE 1967) 

 apparently because their abundance was not determined. 



