John F. Kennedy dedicating the Fryingpan-Arkansas Project, 1962. Courtesy National Archives

In theory, one of the benefits of interbasin water transfers is spreading risk. One basin may have drought while the other does not. But for folks on the Arkansas River in Colorado, that may not work out so well, based on new tree ring analysis by Jeff Lukas and colleagues. Chris Woodka of the Pueblo Chieftain explains:

“It has always been thought that if you are bringing in water from both sides of the Continental Divide, you have protection. That is not the case,” said Jeff Lukas, of Western Water. “While they vary from year to year, the dry years and wet years in both basins show a strong correlation.”

The Fryingpan-Arkansas Project delivers 63,000 acre feet per year from the Colorado River Basin through nearly 30 miles of tunnels to the Arkansas River Basin on the east slope of the Rockies. It’s one of the smaller water projects on the Colorado. To get a sense of scale, the Metropolitan Water District of southern California moves about 20 times as much water annual through its Colorado River Aqueduct, which is one of the largest interbasin transfers on the river.

In addition to supplying water for irrigation and municipal use, “Fry-Ark,” as they call it, also has one of the coolest names of any water project in the West.