Beware the Wet Year

The stories are everywhere – record precipitation and snowpack in California, atmospheric rivers crashing across the Pacific Northwest, and lingering above-average snowpack across Colorado, Utah, and Wyoming. And while short-term relief is welcome, we shouldn’t break out the party hats quite yet. As Mother Nature often shows us, we never really know what is right over the horizon – we need to be prepared.

We still have a long way to go before taking our foot off the gas in encouraging everyone across the Colorado Basin towards greater conservation measures, smart water sharing agreements, and stabilization of the system overall.

Certainly, California’s statewide snowpack numbers are great – over 160% of average in early April – even inspiring Governor Jerry Brown to recently declare the end of the current drought. Upper Basin states are rolling in the numbers as well – the Colorado River basin is currently at 122% and every major river basin in Utah is at or above historical average. But not to throw a wet blanket over this year’s good news, we still have a long way to go before taking our foot off the gas in encouraging everyone across the Colorado Basin towards greater conservation measures, smart water sharing agreements, and stabilization of the system overall.

The Colorado River is currently over allocated to the tune of more than a million acre feet (one acre foot is about 325,000 gallons) per year – there is physically not as much water in the river as is being taken out. The main storage reservoirs in the system, Lake Mead and Lake Powell, are both under 50% of their capacity. In order for the system to be sustainable, and in preparation for the uncertainty of more bouts of lingering drought and climate change, we must all work together to support a stable and reliable Colorado River system – from the headwaters in the Colorado Rockies to the lettuce fields of Yuma and beyond.

Even with a few wet years, climate impacts are reducing flows on the Colorado River. A recent study by Jonathan Overpeck and Bradley Udall illustrates that warmer temperatures on the river between 2000 and 2014 accounted for a reduction of at least a half-million acre-feet of water a year – the amount needed to support 2 million people. The study concludes that warming temperatures alone could cause Colorado River flows to decline by 30% by midcentury if solutions are not implemented.

Snowpack! Snowpack! Snowpack!!

While water levels in both Lake Mead and Lake Powell will likely rise significantly this summer, it would be unwise to give up on collective and collaborative efforts across the Southwestern US to develop agreements and practices to conserve water across the Colorado River basin. Lake Mead is still over 140 feet below full, and even with a projected rise in Powell to bring it to nearly 66% full by the end of the water year, we still have a long way to go. One good snow year is nice, but the long-term effects of prolonged drought and substantial overuse mandates diligence, effort, and flexibility in how we interact with our delicate yet crucial water supply in the Southwest.