Though it is probably not news to most Moabites, data shows that this part of the state is in dire need of storms this winter. The Natural Resources Conservation Service recently released a pair of reports that illustrate the current water conditions across Utah. While the state overall is having a just below average water year thus far, southeastern Utah is lagging. However, the reports released on Jan. 1 do not take into account the most recent storms that brought more moisture to the area at the end of last week.
The weather station at Canyonlands Field Airport operated by the National Weather Service reported on Jan. 22 that Moab’s month-to-date precipitation total was .71 inches. Notably, national climate data shows that Moab’s average precipitation for January is .63 inches. As of Jan. 22, The Weather Channel predicted a small chance of rain on Friday , Jan. 25, but shows no other precipitation coming until February.
While the storms continue to bring much-needed moisture to southeastern Utah, the snowfall will increase avalanche danger. “Avalanche concerns will be enhanced by this snowfall,” stated the NWS.
The first of the NRCS reports, titled Utah Water Supply Outlook, begins by noting that the current snowpack is double what it was at the beginning of 2018. However, that is not saying much since last year’s snowpack on Jan. 1 was about 51 percent of the normal level. The state’s snow water equivalent, which measures the amount of water contained in the snowpack, is close to normal for the state overall, but in Southeastern Utah, it is only 72 percent of nomal.
Though it is still below average, the snowpack totals in the southeastern part of the state are currently much better than the previous year. According to the report, snowpack was only at 12 percent this time last year. Thanks to a wet October, the seasonal accumulation (October-December) of precipitation is now at 131 percent of the average. “Soil moisture is at 41 percent compared to 16 percent last year,” the report said.
Since the winter of 2017-2018 was so dry, reservoirs are depleted throughout the state, and Ken’s Lake is no exception. Due to “the abysmal 2018 water year,” reservoirs saw heavy use throughout the summer, the report said. The report notes that Ken’s Lake was at 54 percent of its capacity last year but is now at a measly 13 percent.
Due to the government shutdown, the NRCS is short-staffed, so the report only included forecasts for February through May and not January or June. The usual stream-flow forecasts were also not available. The report did point out, “A weak El Niño is forecast for this winter and may augment Utah’s precipitation totals – particularly for southern Utah.”
The second of the two reports, titled Utah Climate and Water Report, is intended to “provide a snapshot of current and immediate past climatic conditions and other information useful to agricultural and water user interests in Utah.” The report presents the conditions of two distinct geographic regions, low elevation valleys and high elevation (more than 6,000 feet) mountainous areas, using two sets of data from a variety of sources, including the United States Geological Survey, the US Department of Agriculture and the NRCS. The Soil Climate Analysis Network monitors the areas that are vital to agricultural production, while Snow Telemetry (SNOTEL) data looks at areas where the water supply is generated.
Southeastern Utah persists in “a Severe to Exceptional Drought,” the report noted. The scant 0.3 inches of precipitation that fell in December brought the water-year total to 3.4 inches and did little to alleviate the drought. “For the second month in a row, southeastern Utah, the region needing it the most, got the least precipitation,” the report said.
The Climate and Water Report presents a water availability index (WAI) for each region. The WAI is “an observed hydrologic indicator of current surface water availability within a watershed,” explains the report. It is calculated by combining current reservoir storage with the previous month’s streamflow. The WAI value is displayed as a percent chance of non-exceedance. “While this is a cumbersome name, it has the simplest application,” the report claims. It describes how the percentage can be thought of as scale from one to 99, with one being the driest possible conditions and 99 being the wettest possible.
Moab’s water availability index is currently at 12 percent. That means only 12 percent of historical events have had less total water supply. The last time Moab had so little water availability was in 2013. Before that, 1989 was the most recent year with a similar WAI. More information on the WAI can be found at www.ut.nrcs.usda.gov/snow/ on the water supply page. It includes the entire period of historical record for reservoir storage and streamflow with water supply outlook reports dating back to 1925.
The data analysis provided by the two reports “can be used to increase irrigation efficiency and agricultural production,” claims the NRCS. It does note, however, that “there are limitations due to data quality, quantity and spatial application.” It also points out that while the NRCS continues to operate during the Federal shutdown, it may undergo interruptions in service and site maintenance. Both reports are available to the public on the NRCS website.