The Board of Consultants recommanded that the need for additional 

 water in Deer Creek be investigated. If the need became apparent., a 

 method was to be devised whereby water could be supplied to irrigation 

 interests from the Sacramento River ^, and an ample, continuous flew main- 

 tained in Deer Creek for perpetuation of the salmono 



Before operations began and each year since^ adult salmon have had 

 difficulty negotiating the Stanf ord-Vina Dam. An inadequate fish ladder 

 at th:.s dam operated only occasionally. Usually the fish battered them- 

 selves to death or sustained major injuries on the shallow apron of the 

 dam. The State of California remedied this condition in part when it 

 built a functional ladder over the south end of the dam. Even with this 

 new ladder J, however j low flows in the stream make it extremely difficult 

 for salmon to pass this dam. 



T^rnsn the stream flow diminishes and irrigation demands increase, 

 the creek becomes so warm that often late arrivals are killed before 

 they reach the dam. In 19U5ji close inspection of Deer Creek below the 

 Station^ imjtiediately after the onset of lethal water temperatures, 

 revealed 283 dead adult salmon. In 19^6, despite rescue effortSj, ii73 

 salmon died on June 2U. By May 20, 19^7^ water temperatures were high 

 enough t<;' kill 108 salmon in this section. 



The downstream migration of young salmon and steeihead trout^ as 

 mentioned before, is reduced seriously by irrigation diversions at the 

 mouth of Deer Creek Canyon and at Stanford-=Vina Dam^ despite operation 

 of so-called screens in all ditches. Losses of young fish in diversions 

 are aggravated in years of low precipitation because irrigation demands 

 begin earlier than usual and nearly all of the stream flow is taken while 

 the migrants are still moving downstream in large numbers » However j, 

 CaUfornia State Fish and Game officials have condemned these screens and 

 have designed new and adequate ones. A new rotary screen, together with a 

 by-pass back to the creek, has recently been installed on the south canal 

 of the Stanford-Vina Irrigation Company by the California Division of 

 Fish and Game. Elimination of fish losses in the diversions from Deer 

 Creek would go far to improve the contribution of that stream to the 

 fishery resources of California, 



Effect of Transplanting Program 



Losses of both adult and yoiong salmon in Deer Creek cast doubt on 

 the ultimate success of the transfer activities carried on from 191^1 

 through 19ii6. That these losses are not the result of lack of space 

 is indicated by surveys of spawning grounds and natural holding areas, 

 which show that space is available for more than 15^,000 nests. This 

 includes 5 miles of new spawning stream made available by constnaction 

 of a fishway over Lower Falls which was first used in 19ijU. Water 

 temperatures (except for those in the lowermost section of the stream) 

 are suitable for holding of adult salmon and for egg incubation. 



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