tl;dr The 1922 Colorado River Compact was supposed to sidestep the “doctrine of prior appropriation”, assuring slow-developing Upper Colorado River Basin states that their fast-growing downstream neighbors wouldn’t lock up all the water. But while that may be true on paper, 21st century reality suggest “prior appropriation” is back.
longer: Bret Walton’s Circle of Blue piece last week on Colorado River Basin water use plans as Lake Mead drops makes clear the states of the Upper Colorado River Basin – Wyoming, Utah, Colorado and New Mexico – will never get the water promised them under the 1922 Colorado River Compact. The result is a sort of de-facto “doctrine of prior appropriation”. By building quickly into their full share, the states of the Lower Basin – California, Nevada and Arizona – may have effectively pre-empted their Upper Basin neighbors:
Utah — like fellow upper basin states Colorado, New Mexico, and Wyoming — is not using all the Colorado River water it was granted by a 1922 interstate compact. The four states have the legal authority to increase their Colorado River diversions.
However, the water they seek may not be available. The calculations of availability stem from wetter hydrological conditions and supply forecasts made nearly a century ago. Under the 1922 compact, the upper basin is entitled to 7.5 million acre-feet. A later agreement apportioned each state a percentage of the available supply. The upper basin’s average annual use between 2007 and 2011, the most recent figures, was 4.6 million acre-feet.
This is the outcome Colorado water lawyer Delphus Carpenter, the person arguably most responsible for the shape of the complex institutional plumbing governing the Colorado River, was trying to avoid back in the 1920s.
Dubbed by his biographer “the silver fox of the Rockies,” Carpenter was a small-town lawyer in Greeley, Colo., when a battle erupted between his state and neighboring Wyoming over water in the Laramie River.
Representing the Greeley-Poudre Irrigation District, this son of a homesteading irrigation farmer ended up arguing before the United States Supreme Court, defending Colorado’s water in a case that lead to the landmark 1922 decision in the case of Wyoming v. Colorado.
Wyoming had argued that, because its farmers had first put the Laramie’s water to use, their water rights should trump the Colorado irrigators who came after. The U.S. Supreme Court agreed, dealing a devastating blow to not only the Colorado farmers who had hoped to use the Laramie’s water, but to Colorado’s hopes for the future.
The battle over the Laramie was tiny compared to the growing conflict over the Colorado River, where tributaries flowed through seven U.S. states before discharging into the Gulf of California. Development patterns were happening unevenly across the region. If the “doctrine of prior appropriation” upheld by the U.S. Supreme Court in Wyoming v. Colorado was applied to the basin, Colorado and the other states feared fast-growing California would simply get it all.
Carpenter is the architect of the alternative: a compact among the states that divides the water evenly at the start, rather than giving it to whoever uses it first. It appeared at the time the compact’s drafters had sidestepped prior appropriation.
In the legal literature, prior appropriation has been a bit of a Schrödinger’s cat – “alive but irrelevant“, perhaps dead completely. And I’m stretching the argument to even invoke prior appropriation here. It’s not being invoked in the Colorado River Basin as a legal matter. It’s simply the practical nature of the thing.
California, Arizona and Nevada developed their full share of the river’s water. The other states didn’t. And now there’s no water left.
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