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<br />
<br />CHRONOLOGY OF THE 1976-77 DROUGHT
<br />
<br />47
<br />
<br />situation in the mountains in March 1977, the
<br />Denver Water Board requested residents to
<br />voluntarily stop watering lawns. Later, the
<br />deteriorating water supply forced the Denver
<br />Water Board to abandon their program for vol-
<br />untary reductions of water use and to restrict
<br />la wn watering to 3 hours every third day. In
<br />Grand Junction, Colo., and Price, Utah lawn
<br />watering was restricted to 2 days per week,
<br />and in Cortez, Colo., lawns could be watered
<br />only 3 days per month. In July 1977 the city of
<br />Rangely north of Grand Junction had to dis-
<br />continue supplying water to an oil company,
<br />A flow of 76 ft 3/s for irrigation was
<br />released in March 1977 from Taylor Park
<br />Reservoir in the Gunnison River basin east of
<br />Grand Junction, Colo.,-a very unusual occur-
<br />rence for that time of year.
<br />Monticello, near the southeast corner of
<br />Utah, imposed a strict water use limit of 50
<br />gal per person per day for about 2 months.
<br />When rationing ended on July 1, 1977, after
<br />four new shallow wells were put into produc-
<br />tion, the rates were increased so that residen-
<br />tial usage over 15,000 gal per month would be
<br />very expensive. Also, plans were made to drill
<br />a deep well to provide a firmer supply in the
<br />future.
<br />Vernal, Utah set up a water rationing
<br />program on April 1, 1977 on an honor system.
<br />Outside water use was to be limited to twice a
<br />week between the hours of 6 and 12 p,m, A
<br />brochure, "The Water Hole is Drying Up," was
<br />prepared to educate the public on the need for
<br />and how to practice conservation; and it was
<br />used by the media and the schools.
<br />The Governors of Colorado and Utah ap-
<br />pointed special committees to coordinate acti-
<br />vities related to the drought, In Utah, the
<br />committee approved $500,000 of special funds
<br />mainly to drill and equip wells for domestic
<br />supplies at 19 locations in eight counties, The
<br />committee also approved loans totaling
<br />$204,000 to provide emergency water for live-
<br />stock from new wells and pipelines.
<br />Disaster designation was approved for 41
<br />counties in Colorado, New Mexico, Utah, and
<br />Wyoming.
<br />
<br />The Great Basin-WRC Region 16
<br />
<br />The Great Basin (fig. 18) includes most of
<br />Nevada, western Utah, and parts of California,
<br />Idaho, Oregon and Wyoming. The drainage
<br />
<br />I
<br />
<br />consists of numerous closed basins with the
<br />headwaters of many streams in mountains
<br />where snow is the predominant form of pre-
<br />cipitation. The streams traverse valleys down
<br />to lakes, sinks, or playas where there are no
<br />natural surface outlets.
<br />A summary of the 1976-77 drought is pre-
<br />sented in the next few paragraphs.
<br />Below normal precipitation, particularly as
<br />snow in the mountains, produced a severe
<br />drought, Frequency analyses show that on the
<br />basis of streamflow, the drought had an aver-
<br />age recurrence interval greater than 100
<br />years. The low runoff had to be augmented by
<br />substantial reductions of storage in reservoirs,
<br />and the level of Lake Tahoe was below the
<br />level of its outlet for 3 months.
<br />Ground-water levels in many basins did not
<br />change much, but locally declines ranged up to
<br />24 ft. Water quality of both ground and
<br />surface water was not seriously affected.
<br />Water use was restricted in some communi-
<br />ties, many new wells were drilled, and emer-
<br />gency actions had to be taken to provide water
<br />for towns and for livestock.
<br />
<br />Previous Droughts
<br />
<br />Drought in the Great Basin is nothing new.
<br />In 1934 when snow surveying was a relatively
<br />new technique for forecasting runoff from the
<br />snowpack, the water content of the snow cover
<br />on March 29 in the Weber River basin north of
<br />Salt Lake City, Utah was only 27 percent of
<br />that in 1933. The winter was warmer than
<br />average; therefore, some water users started
<br />irrigating as early as the latter part of March
<br />and most of them were irrigating by April 15.
<br />Releases of water in storage started on
<br />April 18 about 2 to 2.5 months earlier than
<br />usual. There was not enough water to meet
<br />everyones' needs, but most of those holding
<br />older water rights temporarily gave up part of
<br />their water to those with junior rights so that
<br />all would be able to start irrigating. The
<br />snowmelt runoff was short-lived and peaked
<br />early, about May 8.
<br />To augment the water supply, Federal
<br />funds were used to pay for the lowering of the
<br />outlets of four lakes. About 200 acre-ft was
<br />obtained in this manner. Between late June
<br />and early August 1934 several canal companies
<br />turned off their diversions so that water could
<br />be used by other canal companies to save hay
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