REPORT OP THE PISH AND GAME COMMISSION. 



59 



of the large canal owners are resisting our efforts to install screens in 

 their canals. These owners object on the grounds that the screens are 

 impractical and will impede the flow of water. This is a flimsy excuse, 

 as experience has proved that the largest canals can be screened and 

 the flow of water be undiminished, if they are properly cleaned. The 

 parallel bar screen can be made to do good work and not caiLse any 

 trouble under normal conditions. During extremely high water when 

 floods prevail in the streams caused by melting snow or storms in the 

 mountains carrying down an excess of floating matter, the screens can 

 be removed for a short time to allow the debris to pass. When condi- 

 tions are normal the screens can be replaced. It would be folly to say 



Fig. 40. Fishway at Bonally Dam, on the Salmon River, Siskiyou County. Photograph by 



I. Eldredge. 



that the large canals can not be screened. If we can not have them 

 screened all the time, we should make an effort to save as many fish as 

 possible by keeping the screens in place when it can be done without 

 damage to the flow of water in the canals. 



A screen is being installed in the Pacific Light and Power Company 's 

 canal at Borel in Kern County that works in sections on a revolving 

 shaft. It can be cleaned at any time by turning a crank that turns the 

 screen sections edgewise with the current and allows the debris to float 

 down the stream. As soon as the debris is washed off, the screen is 

 turned back in place. Some such device can be arranged if the parallel 

 bar screens are considered too hard to clean. Any of the types of 

 screens that we have recommended will work, if they are cleaned. We 

 find that the trouble appears to be that some of the owners of the 

 larger canals do not want to pay for the extra help required to clean 

 the screens. 



The commission plans to rigidly enforce the law regarding the 

 screening of ditches and no excuses will be entertained. Taking it as a 



