This winter, abundant snowpack across the interior West all but erased severe drought conditions and temporarily reduced the risk of a water shortage along the Colorado River. While a significant improvement from 2018, supplies remain vulnerable due to overuse and climate change, according to estimates from Western Resource Advocates whose associates are closely watching changes in seasonal precipitation and are advocating for solutions to ensure overstressed rivers can continue to meet the needs of cities, farms and ranches, water-based recreation, and the environment across the West.
“Warming temperatures throughout the West affect the type of precipitation we receive and when we receive it. This in turn has significant implications for river flows, agricultural production, water-based recreation, drinking water supplies, reservoir levels, and riparian habitats,” said a press release from the organization.
In addition to changing the type of precipitation, increasing temperatures are also causing Western snowpack to melt one to four weeks earlier, on average, than in prior decades, contributing to reduced runoff. Dust on snow, soil moisture, and wind are also factors that affect the timing, speed, and amount of snowmelt and runoff.
Record-low snowpack in 2018 and a hot and dry summer led to historically low flows, and warmer water in Western rivers. Last year, the Yampa River in Colorado experienced its first-ever “call” to curtail use due to low flows. While current snowpack in the Yampa Basin is well above average, stream flow is expected to be around average.
Despite snowpack reaching up to 200 percent of the 30-year normal in parts of the Four Corners, the region is still experiencing drought conditions, with severe drought lingering in northwest New Mexico, officials said.
Heavy snowfall in the Upper Basin this year will help water levels in Lake Powell, but it will not be enough to make up for years of overuse and rising air temperatures in the Colorado River Basin. Lakes Powell and Mead each remain around 40 percent full.
“Low snowpack and stream flows harm Western agricultural producers, can devastate outdoor recreation businesses, and stress municipal water supplies. The Colorado River alone provides drinking water to roughly 40 million Westerners and supplies four million acres of irrigated farm and ranch land across seven U.S. states and Mexico,” officials said.
WRA is working to help states, cities, and water users across the West to increase their water security by enacting smart conservation strategies. One approach, called demand management, would compensate willing water users who temporarily reduce their consumption in order to keep more water in rivers and reservoirs. WRA also has a suite of tools, including a land use guide, to help growing Western communities integrate water conservation and efficiency into their planning and development efforts.