72 FISH AND GAME COMMISSION 



REPORT OF THE BUREAU OF HYDRAULICS 



By John Spencer, Chief 



This past biennium has been a most active one for this Bureau. 

 "Work has materially increased, due to a number of factors and a slight 

 increase in personnel has been necessary. 



The Bureau does considerable engineering work for other bureaus, 

 such as surveys, plans and estimates in connection with hatchery water 

 supplies, examination of proposed new sites, and other examinations ; 

 designs and investigations for the patrol and game conservation, and 

 such other work as can be done to better advantage by this Bureau. 

 On July 1, 1936, one of the personnel of this Bureau was assigned to 

 the work going forward on the Central Valley Hatchery and so con- 

 tinued until its completion. 



The work on fishways has gone forward and a number of new ones 

 have been installed and placed in operation. Installations in place have 

 been checked, and wherever necessary arrangements have been made 

 for repairs or improvements. 



The exceptional high waters throughout the State in 1937-1938 

 took out several dams and some of these will probably not be rebuilt. 

 In addition, it has been possible to effect the removal of a number of 

 other dams that have become obsolete. The removal of these dams very 

 materially improves stream conditions for migrating fish. 



On the South Fork of the Eel River is a dam maintained by the 

 Benbow Company which has received cozisiderable attention from the 

 public and conservationists. IMuch of this adverse criticism had its ori- 

 gin during the early period of construction and use of this dam, and 

 unfortunately, the first concrete fishway was taken out by high waters, 

 due to the poor foundation work by the owners. A temporary fishway 

 was installed and fish, except for a slight delay, passed this barrier. 

 This was replaced by a reinforced concrete structure which has func- 

 tioned satisfactorily^ 



In addition, there has been built a second fishway on the opposite 

 side of the dam, and just recently a slight addition has been made with 

 the hope that this fishway will be more effective, though it is doubtful 

 if it can ever be classed as an entirely satisfactory one, as water regu- 

 lations may not be had and its location is not in the general line of 

 fish movement. 



In years past the Fish Conservation Bureau has counted fish at 

 the original fishway, and plans provide for a more elaborate count in 

 the fall of 1938. The information thus obtained will without doubt 

 give considerable data as to the kind and number of fish moving up 

 beyond this barrier. 



Every effort is expended to have fishways repaired or improved, 

 or new ones installed on dams where required, Avithout resorting to law. 

 In two eases, however, it was necessarv to invoke court action. One of 



