Current Water Situation:
Current Conditions
August 2009
The wet spring months (particularly April and June) have turned a fairly normal water year into one of water abundance. The National Drought Monitor (http://drought.unl.edu/dm/monitor.html) reports that although abnormally dry, to severe drought conditions persists for the western U.S. coastal States much of the Mountain West is currently experiencing normal water supply conditions. This is true for Utah which has experienced fairly average precipitation ever since the 2005 water year put an end to the state’s most recent drought.
Normally the amount of water stored in Utah’s reservoirs, due to spring runoff, peaks around the first of June. Then as water users, primarily irrigators, call upon stored water supplies, the reservoir levels decline throughout the summer and into the fall. In 2008 an abnormally wet spring resulted in reduced irrigation demand in the early summer. Consequently, reservoir levels around the state continued to rise, peaking around the first of July. This condition was repeated in 2009. A very wet April and a record setting string of rainy days in June significantly reduced the demand for irrigation water around the state. Meanwhile, Utah’s reservoirs continued to experience a net increase in stored water through the month of June. As a result the amount of water stored in Utah’s reservoirs on August 1st was only about one percent less than was stored on June 1st. Typically, Utah’s reservoirs experience a 10 percent decrease of stored water over the same period. This situation should bode well for the end of the year water supply conditions and translate into significant carry-over storage for next year.
Although 2005 and 2006 went a long way towards replenishing the Utah's dwindling reservoir storage, the 2007 and 2008 water years did not continue the trend. In 2006 statewide reservoir storage peaked at just over 80 percent of the total capacity. The amount of water stored in Utah’s reservoir peaked at 76 percent during the 2007 water year and 70 percent during the 2008 water year. This estimate is based upon storage in 29 of the State's largest reservoirs, excluding Lake Powell and Flaming Gorge. These 29 reservoirs have a combined storage capacity of 5.29 million acre-feet, roughly 85 percent of Utah's estimated total storage capacity of 6.19 million acre-feet (again excluding Lake Powell and Flaming Gorge).
About 60 percent of the unfilled capacity shown in the graphic above is in Bear Lake. Although Bear Lake currently has about 490,000 acre-feet more water than it had at the end of the drought in 2004, it is still about 800,000 acre-feet below capacity and will require at least a couple of very good runoff years to refill. Bear Lake’s low level is reflected by the Bear River Basin’s Surface Water Supply Index (SWSI), which at -2.45 continues to classify the Bear River Basin as being in a moderate drought condition. Although the depleted reservoir storage in Bear Lake implies that the basin is still experiencing moderate drought conditions, there have been adequate supplies in the basin for agricultural uses as well as M&I uses. The only other area of the State that is currently experiencing moderate drought conditions based upon its SWSI is the Moab area.
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