15 June 2022 — 0958 mdt

Montana is cold and wet, but the
Colorado River basin is hot and dry

By James Conner

When it’s as cold and wet as Montana has been the last few days, global warming and historic drought are hard to take seriously — until one looks beyond the northern Rockies to Phoenix, Arizona, a thousand miles south southeast of Kalispell and an order of magnitude more populous. Here’s Phoenix’s current forecast:

Kalispell will warm to 65°F today, and to 80°F tomorrow. The Flathead River will keep rising through next week, and may stay high for several weeks thereafter. Then, through the hot months of July and August, the river’s streamflow will decrease by an order of magnitude and the Flathead basin’s residents will worry about fires, not floods.

Meanwhile, in the Colorado River basin, residents would welcome flooding that would refill Lakes Mead and Powell, the huge reservoirs behind Hoover and Glen Canyon Dams. But that’s not likely any time soon. The Colorado’s basin is in the midst of a historic drought. Much less water than assumed by the compact governing the seven-state, two-nation, basin is flowing down the river, demands for water are rising, and the crisis long forecast by experts such as Eugene Clyde LaRue is here. For a good summary of the situation, see The Colorado River Is in Crisis and It's Getting Worse Every Day in the 14 May Washington Post.

Map by U.S. Geological Survey.

West of the Colorado’s basin, Utah’s Great Salt Lake is drying up, reduced to one-third of its maximum size by evaporation and reduced inflow from rivers whose waters are being intercepted by fast growing and water hungry Salt Lake City. As the lake bed is exposed and dries, the risk that it will release toxic dust into the city grows.

According to a lengthy report in the New York Times, Salt Lake City’s per capita water consumption is approximately 20 percent higher than that of Phoenix and Los Angeles.

Yesterday, while Kalispell swam in steady rain and shivered in the low forties, I threw another log on the fire and finished reading Science Be Damned, the definitive account of how cockeyed optimists and lying opportunists based the Law of the [Colorado] River on estimates of streamflow that were significantly higher than reported and predicted by the scientists who measured the river’s flow.

Although the river was over-allocated from the gitgo (negotiations for the Colorado River Compact began in 1922), decades passed before water consuming development made use of the river’s last drop. Thus managers avoid making the hard choices that nature finally would impose on them.

Montana’s river basins are wetter than the Colorado River’s basin, but they, too, are subject to the drying of the environment that results from global warming. Yes, rivers under the Big Sky still can roar and rip houses from the riverbank, but as we know from recent years, they can diminish to a trickle, warm to fish killing temperatures, and leave trout belly up in shallow pools where once clear cold water tumbled downstream at the beginning of its long journey to the sea.

Do not be fooled by a somewhat freakish flood. Global warming is upon us, and so are long periods of low water.