Desert hydrology: Science Moab highlights talks with Eric Kuhn, Jack Schmidt, Brian Richter, and Arne Hultquist #ColoradoRiver #COriver #aridification

Click the link to read the article on the Moab Sun News website (Science Moab). Here’s an excerpt:

In the desert, few issues are as crucial as water. As a historic megadrought continues in the West, water usage is at the top of mind for many scientists. Hydrologists can help us understand how and when to enact new water policies. In this week’s column, Science Moab highlights important messages from conversations with hydrologists, speaking with Eric Kuhn, Jack Schmidt, Brian Richter, and Arne Hultquist.

Science Moab: Are we bound by water usage policies enacted years ago? If nature can’t sustain those, what then?

Eric Kuhn: One hundred years ago, we had some flexibility because the river was not very well-used. Today, not a drop of the Colorado River reaches the Gulf of California, so we don’t have that luxury. The way I look at it is: we legally allocated water based on an assumption that this river system had about 20 million acre-feet. Today, we think it’s more like 13, and it might be less in the future with climate change. Predictions and models show that increasing temperatures are going to reduce flows to the Colorado River. The drama is not how much water we’re going to have in the future — we know it’s going to be less. The drama is how we’re going to decide who gets less water, and when…

Science Moab: At the start of 2021, Lake Powell was at 41% of its capacity. Why should we be so concerned that Lake Powell levels continue to fall to all-time lows?

Brian Richter: Lake Powell serves three really important benefits. One is that it generates hydropower from the Glen Canyon Dam, which provides electricity throughout the southwestern United States. Two, Lake Powell is important for tourism, which is impacted by falling water levels. But by far the biggest concern is that if Lake Powell drops by another 85 feet — and for reference, the lake level dropped by more than 30 feet in 2020 — then the lake will drop below the hydropower outlets, so all the electricity production out of Glen Canyon Dam will stop. But even worse is that it will become physically impossible to move enough water into the Lower Basin states to provide for their water needs.