The Colorado River is a crucial water source for seven states (Wyoming, Colorado, Utah, New Mexico, Arizona, Nevada, and California) and Mexico, and like many shared rivers has its share of challenges. We talked to Doug Kenney—director of the Western Water Policy Program at the University of Colorado and a member of the PPIC Water Policy Center research network―about balancing priorities in managing the river.
PPIC: What’s the basin’s biggest challenge currently?
DOUG KENNEY: That depends on what part of the basin you’re in and what sector you work in. There’s no shortage of things to worry about. Right now, most would probably say it’s the effort to maintain the levels of water stored in the big reservoirs, Lake Mead and Lake Powell. Those reservoirs provide a lot of benefits—drought protection, recreation, and hydropower—but only if they have enough water in them. They’re about half full right now, which is about as low as they can go before mandatory cuts in water deliveries—or curtailments—kick in. It’s a math problem, essentially—managing water coming in versus what’s going out. So far in this century, people have pulled more water out than consistently flows in. Obviously, that has to change.
The more chronic issue is that the Colorado has been treated more like a plumbing system than a river, so there’s been a lot of environmental damage to the river. The big environmental concerns in the basin are a result of reduced flows and some water quality issues, such as high salinity, loss of valuable sediments, and increased water temperatures. The real challenge is to remind people we’re talking about a river—the most important ecological resource of the southwest United States.
PPIC: What efforts are underway to address the problems?
DK: The big effort at the moment in the Lower Basin is called drought contingency planning, which would help stabilize (and ultimately increase) the amount of water stored in Lake Mead. The negotiations among California, Arizona, and Nevada have gone remarkably well in this regard, although each state still has internal challenges to work through. For example, Arizona is concerned about looming curtailments of their water supply, while in California the big sticking point is the Salton Sea. The sea has become a critical issue as successful efforts to use water more efficiently in Southern California agriculture have reduced inflows, resulting in a host of environmental and public health issues. In both of the situations, the underlying desire is to protect water supplies for urban users in a way that doesn’t impose undue burdens on agricultural regions.
Another issue worth watching is the 2012 agreement between the US and Mexico that laid out cooperative efforts to manage the river. The agreement expires at the end of this year, and a new one is needed to maintain positive momentum and cooperation. Key issues between the US and Mexico include restoring the river’s delta ecosystem, enabling Mexico to store water in Lake Mead, and sharing water shortages during drought. While cooperation on the Colorado between the US and Mexico has gotten dramatically better in the past decade, people are worried that the tensions arising from the current political environment at the national level could spill over to the negotiations. But so far, the two sides are still talking, and people still seem pretty optimistic about reaching an agreement.
PPIC: How do upstream states view California’s efforts to manage its Colorado River supplies?
DK: Everyone in the basin pays attention to what’s going on in California. California has the largest and arguably the most legally secure allocation of Colorado River water rights. California’s dependence on the river is shaped by many factors, including other water issues within the state. For example, the project to build tunnels under the Sacramento-San Joaquin Delta—if it progresses—would go a long way to create some room for compromise and creativity on how Southern California uses its Colorado River supplies. With every passing year it becomes more difficult to talk about the Delta and the Colorado as separate challenges. Everything is connected to everything else.
PPIC: How is climate change affecting the river basin?
DK: We’re already experiencing big climate-related changes in the basin. It’s already nearly 2 degrees Fahrenheit hotter this century compared to last, and by 2050 it will be closer to 5 degrees hotter. That results in higher evaporation rates, increased water demands, and reduced stream flows. Climate change is water change, and more heat works against all our water management goals. During this drought, precipitation has dropped only slightly but stream flows are way down, partly because it’s hotter. And that will continue―this is the part of climate projections we’re most certain of. Continued warming and the related reduction of stream flows is a huge problem.
Water management is traditionally based on the premise that the future will look like the past, but that’s not a safe assumption anymore. Our physical infrastructure isn’t ideally suited to the projected future hydrology. There’s a similar problem with our institutional infrastructure. We have a pretty sophisticated management regime that is increasingly out of step with evolving conditions. The good news is that key players in the basin now understand that the climate is affecting everything they do, and that they have to cooperate to find solutions to tough problems. People in the basin are committed to putting in the work, but there’s still a lot more to be done.
Read California’s Water: The Colorado River (from the California’s Water briefing kit, October 2016)
Watch our 4-minute video “Colorado River”
Visit the PPIC Water Policy Center