In addition to the actual dam construction, consid- 

 erable effort was expended in removing dead trees 

 and debris from the impoundment areas of other 

 stream flow maintenance dams constructed in the pre- 

 vious biennium. 



The operation of a large number of these dams and 

 recording of water flows relating to the operation 

 \\ as turned over to Wildlife Protection personnel, and 

 the wardens who were assigned this added responsi- 

 bility have done an excellent job. Generally, the dams 

 are receiving far better and more frequent attention 

 than they had received. 



The problem of measuring water flows below many 

 dams in El Dorado County was largely alleviated by 

 the Mount Ralston Fish Planting Club of Sacramento. 

 This club constructed flow measuring weirs below 12 

 existing dams, thus making it possible to measure, 

 record, and change water flows quickly and easily. 



Lake Improvement 



Flow maintenance dams frequently benefit a lake 

 through enlarging it as well as benefiting the stream 

 below. However, a number of projects were planned 

 specifically to create or improve lakes. Some of these 

 projects are listed below. 



In order to stabilize the water level of Chiquito 

 Lake, Madera County, a rock-masonry main dam and 

 saddle dam were constructed. The main dam is 27 feet 

 long and raises the lake about two feet. A 43-foot 

 saddle dam was also necessary to contain the lake. This 

 work has resulted in an increase in surface area from 

 seven acres to a constant high of 20 acres. 



A small dam was constructed on Little Kern Creek 

 with a cement-lined diversion ditch to Little Kern 

 Lake. The purpose of this project was to supply Lit- 

 tle Kern Lake with a constant flow of fresh water, 

 thereby creating improved fish habitat. 



Experimental work was carried on to open public 

 access through dense cattails and tuie growth around 

 Lost Lake, Fresno County, and ponds on the Los 

 Banos Waterfowl Management Area, Merced County. 

 Explosives were used to blow out masses of vegetation. 

 Experiments were also conducted with the use of 

 chemicals to remove the emergent plants. Although 

 results were inconclusive at the end of the biennium, 

 it now appears that cattails and tule growth may be 

 effectively controlled w ithout harm to fish life or sur- 

 rounding agricultural land. 



Hume Lake Dam Repair 



The dam creating Hume Lake, Fresno County, was 

 repaired with Wildlife Conservation Board funds at 

 a cost of 164,905. Before refilling, the pools and tribu- 

 tary streams were treated with chemical to remove 

 warm-water fish. Rainbow trout were stocked and 

 have provided excellent fishing. 



^^it^>yS^ 



'^•'- ■■■,.,c 



Hume Lake Dam, 



(Fish and Game Photo) 



Serious leakage of the dam creating McClure Lake 

 in Madera County was repaired. Forty percent of the 

 dam face was sealed with watertight compounds after 

 removing loose rock and mortar. Additional repairs 

 were made to the footing of the dam by the Forest 

 Service. 



Lake level maintenance dams were constructed at 

 the outlets of Maria, Upper West and Lower West 

 Lakes, Nevada County, to increase their depth and 

 pre\ent seepage losses. In cooperation with the Truc- 

 kee Outdoor Sportsmen's Club, sloping screens were 

 installed at the outlets to prevent downstream migra- 

 tions of fish from the lake. Many fish formerly per- 

 ished each year when the outlet stream went dry. 



winter Carryover Experiment 



Dry Lake, San Bernardino County, at 9, 100- feet al- 

 titude, averages about five feet deep. Due to heavy 

 winter ice formation, the carryover of trout in this 

 lake is virtually nonexistent. 



In attempting to improve the winter carryover of 

 trout b\- increasing the depth, one case of 40 percent 

 gelatin dynamite was detonated in five different loca- 

 tions. Holes ranging from four feet square and four 

 feet deep to holes 15 feet by 35 feet by 6 feet deep 

 were created. Future checks will determine whether 

 this work is effective. 



In addition to the experimental control of cattails 

 and tules through the use of chemicals, a number of 

 tests were made with other chemicals to control sub- 

 merged aquatic weeds. This control of submergents 

 has proved more difficult than the control of emergent 

 plants. This is because the concentrations of certain 

 chemicals necessary to eliminate weed growth are fre- 

 quently lethal to fish or desirable terrestrial plants. 



