It’s early January, and while snow season in the Southern Rockies continues for another three months, we already see snowpack at 59% of the seasonal average. That is something to celebrate, as the Colorado River Basin has been in an extended drought going on 24 years, with consequences for people, birds and every other living thing that depend on rivers in this region. But the abundant start to the snow season does not mean Colorado River managers get a reprieve from their aggressive efforts to reduce water use and reform Colorado River operations.
In recent years we have seen “above average” early season snowpack turn into below average snowpack and far-below-average runoff. In 2021 for instance, 85% of average snowpack turned into runoff of 36%. A variety of factors created these dynamics, including fewer storms later in the snow season, warmer temperatures both increasing evaporation and evapotranspiration (evaporation from plants) and drying out soils which then soak up melting snow. Of course, we don’t yet know this how this year will turn out for Colorado River water supply. But we know it is too early to draw conclusions, other than – gee, sure would be nice if it keeps snowing.
With Colorado River reservoirs two-thirds empty, federal and state water managers have sounded alarms, pointing to the risk of infrastructure failure and even the ability to deliver water and hydroelectric power to tens of millions of people. The available storage space in the reservoirs can hold more than three years of the Colorado River’s average undepleted flow. So even a bomber snow season is not going to end the drought. Tom Buschatzke, who leads the Arizona Department of Water Resources acknowledged this in a recent interview with CNN: "One good year doesn't fix us—even a couple of good years doesn't fix us…We've got to rebuild that bank account."
With climate warming projected to increase, there’s an urgent need to balance Colorado River water uses with supply, even to reduce uses below supply so that there’s less risk to the dams, to people and to nature. Best to keep the pedal to the floor on reforming Colorado River management—because while winter storms are inherently good for water supplies, there is no guarantee winters will be long, sustained, or consistent.