Tiis Clark Ditoh takes off from the north bank 11 miles 

 apstreajiip ?\as a capacity of 12 c»f oS, and was screened in 1938. 



The Wapatox Pcwer and Irrigation Canal takes off from the 

 north""ba;nk 16 miles -aps-iireaii,, "and is the^largest and most important 

 dive:rsion on the Nachss Rivero It has a capacity of 565 OofoSoj of 

 which £00 oofoSu is used for power and the rest for irrigationo A 

 loir looss rock dam usually diverts most of the river at this pointp 

 and should he provided with a definite passageway for fish, and a 

 XA.;;able channel approach should be maintained below the damo 



The diversion was first protected by an electric screen installed 

 by the Pacific Power and Light Company in 1930* A battery of rotary 

 screens p located about one-fourth mile below the intake, was installed 

 by 1938, 



The canal rims for nearly 7 miles to two power plants o The power 

 wheels are supplied by penstocks from the canal and operate with a 

 head of approximately 100 feeto 



The water from the power plant flows back into the Uaches River at 

 a point j^ust above the Gleed Ditch take-off o Since the flow from tMs 

 tailrace canal is usually considerably greater than the flow in the 

 river at this point, it has a greater attraction to upstream migrating 

 salmon and steelhead, which have been reported to ascend futiley to 

 the power planto 



The Selah^Naches Canal takes off from the north bank of a side 

 channeT~IT^STeT~upiTreamT' It has a capacity of 136 cofoSsp and was 

 screened in 1938c The Washington State Fisheries Deparfenent operates a 

 fish t^'ap in the screen by-pass to check on the downstream migration of 

 fingerlingSo At times of low water a lowp rubble diversion dam is often 

 constructed across the entire river to divert water into this canal* 



ftiQ Yakima Water Works Dam located 18 miles upstream is composed 

 of a^series of concrete abutments 3 to 5 feet high that have a provision 

 for the use of flashboards during low water periods o A fishway is present 

 at the north end of the dam. 



The Yakima Water Works Canal (Inspected March ISj 1944) takes off ' 

 from the north bank some 20 feet above the dam. A small concrete wing 

 extends diagonally downstream from just above the intake and serves to 

 shixat debris away from the canal » Downstream migrating fish also are 

 apparently shunted out into the stream emd few fish make the reverse 

 turn baok into the canal mouth, but continue on either over the low 

 dam or through the fishway. This is in effect a "Reverse Intake**, and 

 it is certainly less hazardous to fingerlings than the conventional 

 type di diversion. The canal leads to a series of settling basins from 

 which the water is filtered through the ground to be picked up by a 

 perforated pipe gallery. Since it is impossible for fish to get into 

 the water mains, the diversion does not need to be screened, as any fish 



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