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60 f\~...." HYDROLOGIC AND HUMAN ASPECTS OF THE 1976-77 DROUGHT impact on other resources in the basin than originally e){pected. Pumping from the Walla Walla River in May 1977 reduced the flow enough to cause higher water temperatures and low dissolved oxygen which in turn caused a large fish kill. Also, warm water increases the incidence of disease in fish and a higher mortality rate in fish eggs which means the drought will have a long-term effect on fish. Activities Resulting from the Drought By February 1977 electric utilities request- ed the public to reduce the use of hot water and activities that required electrical energy so that water could be stored for future power generation, The response was disappointing; consequently, surcharges were imposed in May 1977. The combination of the public's volun- tary reductions, above normal precipitation in May, and less than expected use of water for the fish migration (see p. 59), increased stor- age available, in reservoirs by June 30. These conditions were sufficient to negate plans for mandatory curtailment of electrical energy. The Bonneville Power Administration reduced power deliveries by 50 percent to consumers with interruptible service, and the aluminum industry, which uses 25 percent of the electri- cal energy in the Pacific Northwest, laid off 500 workers, To conserve water and other energy sour- ces used to generate electric power, the Governor of Idaho asked citizens to leave their air conditioners off during the summer. Many food processing plants in the State were faced with possible interruptions of power which would cause millions of dollars of spoilage to potatoes and fresh vegetables. Luckily no interruptions occurred. Short-term feasibility studies were made by the Geological Survey of proposals to supplement irrigation supplies in the Yakima Valley of Washington. One proposal was to pump water from abandoned mines near Cle Elum, one. was to divert water from the Donney Creek basin to the headwaters of the Yakima River, another was to pump ground water from the Ellensberg basin into the Yakima River, and the other was to develop additional ground water in the Ahtanum-Moxee area near the city of Yakima, About 21,000 acre-ft could be obtained from the abandoned mines near Cle Elum dur- ing the irrigation season, but the cost was pro- hibitive, Use of a computer model of the Ahtanum-Moxee area showed that 450 ft 3/s could be pumped during the summer months when demand would be the greatest. Water- level declines would be large, but the aquifer would recover quickly to near present levels once the heavy stress was ended. Pumps could not be obtained in time to implement the proposed plans, but pumps are now available locally in case drought condi- tions return. Also, the private wells drilled in the spring of 1977 furnished additional water, especially to orchards, which fared fairly well, and the demand for water was less because some field crops were not planted. However, dry land grain production in Washington drop- ped to 60 percent of that in 1976. Low-flow discharge measurements were made in 1977 by the Geological Survey at 1,220 sites throughout the Pacific Northwest to document flows during the unusual drought. Measurements were made at active gaging stations, at discontinued gaging stations, at points where an agency has a specific interest, and at miscellaneous sites chosen to define the hydrology of the region. More than one measurement was obtained during the drought at most sites. The results of these measure- ments will be analyzed in relation to the long- term records, and reports will be prepared on low-flow characteristics of the streams. Water temperatures and specific conductance were also obtained. Public utilities operating reservoirs on the Snake River in Idaho in 1977 were unable to maintain the minimum flows required by their licenses below Hells Canyon Dam and at Lime Point, upstream from the Grande Ronde River. Because the low runoff was unusual, the Federal Energy Regulatory Commission modi- fied the minimum flow requirements but only for the duration of the drought. The State of Idaho received $305,000 of federal funds for drought relief. About $196,000 of the amount received was used to drill new wells, deepen existing wells, and to haul water-all in connection with water supplies for livestock. To provide firm domes- tic supplies in small communities, a few 500- gallon fiberglass tanks were installed. No communities had to haul water, but newspaper J