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Actual Operations under Criteria-Water Year 1978 Water supply in the Colorado River system during 1978 returned to near normal, recovering from the general drought condi- tions of the previous two years, Precipita- tion accumulations in the Upper Basin for the first 6 months of the water year were 120 percent of normal and snow measurements of April 1, 1978, indicated 130 percent of normal snowpack, Since the content of Lake Powell was less than the content of Lake Mead 8,214,000 acre-feet were released from Lake Powell. Releases from the other reservoirs through September 1978 were made accordingly to meet the power productions and other multiple purpose requirements of the system, At the beginning of January and each month thereafter, through June, the forecast was revised based on precipitation and snow data collected through the month, and the scheduled operation was revised accordingly, ~~.-::;- L ~; If ~,......i -~,,"'- .--- ..,..,.,.-,..'........-. ~. J" -. ~. -, "-.'[ .' ..;....::.. ~ ." The Colorado River Basin runoff at Lake Powell for water year 1978 was 11,504,000 acre-feet or 98 percent of the longtime average, The major storage reservoirs on the Colorado River system stayed within the normal operating range during water year 1978 and downstream water requirements were met from carryover reservoir storage, Aggregate storage at the end of water year 1978 was 44,863,000 acre-feet which repre- sented an increase of 2,722,000 acre-feet from water year 1977, A description of the actual operations of each of the reservoirs in the Colorado River Basin follows, Charts 1-10 show hydro- graphs of the monthly outflow from the reservoirs and water surface elevation and active storage in the reservoirs for water year 1978, The Coachella Canal near India, Ail-American Canal System, California. 1