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~11l!t1l;3 (5i./,,-, "- ,.." CHRONOLOGY OF THE 1976-77 DROUGHT 59 average for February and only 0.8 ft higher than the minimum of record which occurred in October 1966. Also, the water was at a record low level for each of eight consecutive months from November 1976 through June 1977. Water Quality A beneficial aspect of the drought was brought about by the additional water diverted from the Columbia River to Moses Lake and Potholes Reservoir, Wash" where algae growth was reduced. The additional water caused a significant drop in the nutrient concentration which is attributed to nutrients in the runoff from agricultural lands. Water temperatures in streams rose be- cause of the low flows. ln a few streams the rise was sufficient to cause fish kills in Idaho and Washington, Intensive monitoring of water quality was done by the Environmental Protection Agency to assess the impact of the drought at Lower Granite Reservoir, along the Lower Columbia River and the Yakima River, and at Grays Harbor. No emergency actions were needed to counteract the effects of the drought. Salt-water intrusion into estuaries was not a problem in the Pacific Northwest. No ser- ious deterioration of the quality of ground water was noted, The Blue Lakes Spring near Twin Falls, Idaho had dissolved-solids concen- trations and nitrite plus nitrate concentrations in the normal range. Forests Forests and range lands in the Pacific Northwest were exceptionally dry in 1977. Lightning started fires in ld'l.ho in April which is unusually early, and more than 100 fires occurred in both Idaho and Washington in April. During the entire fire season in 1977, there were 2,400 forest fires which burned 12,500 acres. ln an average season there are 2,000 fires that burn 8,300 acres; therefore, the losses from fires were not as serious as expected considering the extra dry conditions. However, incidence of fires in Washington was about twice normal. The number of lightning caused fires in 1977 was the fourth highest since 1900. The drought did cause the loss of young, newly planted trees, and reduced the grazing in National Forests. The Fishery The low flows in 1977 that were near or below the minimum of record in many streams of the Columbia River basin, and the lower main stream discharges caused by the reduc- tion in hydroelectric power generation placed an additional strain on the fishery resources. Therefore, an interagency Committee on Fish- ery Operations was formed to determine the amount of water needed to preserve the fishery and to resolve the conflicts between those competing for water for numerous im- portant uses (Committee on Fishery Operation, 1977), Three plans were developed and carried out: (1) Releases from Libby, Hungry Horse, and Dworshak Reservoirs were made to aug- ment the low flows so that the juvenile fish would reach the ocean more rapidly; (2) Spills were made at nine main stem structures to help the young fish to pass the structures more easily and with fewer losses; (3) About 2.8 mil- lion juvenile salmonids were transported by barge and (or) truck from the lower Snake River to the Columbia River below Bonneville Dam. The water actually used in May and' June 1977 for the first two plans was 1.4 million acre-ft, most of which also was used to generate electricity, Surplus electrical energy was delivered to utilities in British Columbia, Oregon, and California to be returned by February 28, 1978. The return of the electri- cal energy was intended to reduce the demand for hydroelectric generation in the Columbia River basin and to allow storage of additional water to offset that used for the fishery, All the energy was returned and the net use of water was about 230,000 acre-ft and the net cost was about $2.2 million. When the fish return in future years, the value of the increased fishery is estimated at $8.8 to $10 million, The truck-barge operation cost al- most $1 million, and the estimated value of the additional fish returning is $4 to $6.5 million. The implementation of the three plans was accomplished at a lesser cost and with less