70 FISH AND GAME COMMISSION 



conservation work done in this period was that in connection with the 

 effort to have a fish screen installed by the Glenn-Colusa Irrigation 

 District on its diversion from the Sacramento Kiver north of Hamilton 

 City. After conferences had failed to effect the desired installation, 

 legal action was recommended which finalh^ resulted in a superior 

 court trial in May, 1930. 



The matter was submitted on briefs. The evidence at this trial 

 showed that the district diverted a maximum of about 1800 cubic feet 

 per second of water (one-half or more of the river flow in summer) 

 from the Sacramento River by means of large diameter pumps, and 

 irrigating about 140,000 acres. The estimates of cost of screen instal- 

 lation by the Commission were from $10,000 or less to $11,800 (the 

 latter figure being a contract price) and in excess of $35,000, as testi- 

 fied to by the district witnesses. In addition to saving fish the proposed 

 screen would keep trash and debris from going through or lodging in 

 the pumps and at times ner-ossitating repairs. 3tr. X. B. Scofield, in 

 charge of the Department of Commercial Fisheries of this Commission, 

 testified that the take of salmon eggs on the Sacramento River was now 

 only one-fifth of what the take was 20 years ago. and most of this great 

 decrease was attributed to losses due to unscreened pumps and diver- 

 sions, and if salmon and other commercial fish were to be saved to the 

 people of the state screening of diversions mu.st be done. The Com- 

 mission introduced, by reports and "untnesses, that as a result of 120 

 days of netting operations below the pumps, the area netted being from 

 less than 1 per cent to 3 per cent of the total canal area, 5575 fish had 

 been caught, about 66 per cent of the salmon caught being dead or 

 injured; and all shad, adult and fingerliug were killed or injured due 

 to passing through the pumps. 



It is seen from the foregoing brief summary that great losses of fish 

 life do occur due to unscreened diversions and that costs of protection 

 are not unreasonable and must be carried out if a valuable asset of the 

 people of the state is not to be destroyed. If a favorable decision is 

 received from the court the work of the bureau will be greatly aided, 

 but in any event the decision will indicate the course of fish conserva- 

 tion with respect to the present screen bill. 



FISHWAYS 



The work of checking existing fi.shways has been continued during 

 the biennium with the view of having existing structures fully effec- 

 tive and new surveys have been made for further installations when 

 the data warranted such procedure. A number of fislnvays for which 

 surveys and plans were made in the preceding biennium have been com- 

 pleted and are now in operation. 



As a result of these installations, improvements and repairs, a larger 

 number of fish have been seen above the dams on which these fishways 

 are located than experienced for a number of years. A few obsolete 

 dams have been blown out or passageways made for fish. The recon- 

 struction of the fishway at the Mendota Weir by Miller and Lux on the 

 San Joaquin River was accomplished and it is reported that more 

 salmon passed this point this year than for a number of years past. 

 Work is going forward on a fishway at the Merced Falls dam of the 

 San Joaciuin Light and PoAver Corporation on the Merced River, This 

 will open up several more miles of stream bed to spawning fish. 



