resources despite the use of the upper river waters for purposes 

 incompatable with the existence of the salmono Briefly, this 

 program proposes through various measures the maximum rehabilita- 

 tion of native and/or relocated salmon runs in the lower river 

 sections below the areas of intensive water development and 

 utilization.) 



The success of the Lower River Program is predicated upon 

 complete utilization of every available, as well as every re- 

 habilita table, fish-producing tributary of the Columbia River 

 below McNary Dam. The potentialities of the Willamette River are 

 too great to allow pollution to remain a factor limiting its full 

 usage for fish production. 



TTone of the Willamette pollution studies made to date reveal 

 the circumstances under which the main stem oxygen block forms or 

 lifts, nor do they indicate more than vaguely, the time. Until the 

 limits of the pollution problems have been more accurately defined, 

 it remains impossible to determine if, or under what circumstances, 

 the Willamette can be utilized in the Lower River Program however 

 great the need for the waters may be. 



1949 Main Stem Willamette River Studies 



A study of the main stem Willamette was undertaken jointly 

 by the Fish and Wildlife Service and Oregon State College during 

 Water Year 1949, in an effort to determine current postwar conditions. 

 It was recognized at the outset that available funds and personnel 

 would not permit as exhaustive a study as obviously is needed for a 

 complete appraisal of the many facets of the pollution problem. 



A series of stations was established over the length of the 

 main stem and on each major tributary close to its confluence with 

 the Willamette River. The geographical location of these stations 

 is listed on Table 1. Duplicate samples were collected at half depth 

 from a single point on the river. It was recognized that the results 

 obtained by spot samplings would be affected by many factors but, 

 under the limiting circumstances, it was assumed that spot sampling 

 would prove sufficiently representative of the actual conditions to 

 serve the intended purposes. 



Each sampling station was visited periodically throughout Water 

 Year 1949. The results obtained are listed in Table 2. 



The summer of 1949 proved somewhat atypical for, as shovm on 

 Table 3, water flows in the main stem were somewhat above average 

 and considerably above those prevailing during the 1944 survey of 

 Merryfield and Wilmot. The July and August flows, however, were 

 substantially equal to those of 1929 when Rogers, Mockmore, and 

 Adams made their studies of stammer conditions. 



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