Nick Cote/KUNC and LightHawk

The Colorado River gets its start in the Rocky Mountains, and flows through small farm and ranch communities in Colorado's high country.

In a 5-4 decision, the U.S. Supreme Court has ruled that the federal government does not have to take affirmative steps to secure water for the Navajo Nation.

The Navajo Nation had sued the federal government, saying a treaty from 1868 compelled the U.S. to take such water security measures for the tribe.

Arizona, Nevada and Colorado intervened against the tribe, in an attempt to protect their interests in Colorado River water. 

Writing for a majority made up of conservative justices, Justice Brett Kavanaugh explained that “the Navajos contend that the treaty requires the United States to take affirmative steps to secure water for the Navajos — for example, by assessing the tribe's water needs, developing a plan to secure the needed water, and potentially building pipelines, pumps, wells, or other water infrastructure.”

But, Kavanaugh said, “In light of the treaty's text and history, we conclude that the treaty does not require the United States to take those affirmative steps.”

Kavanaugh acknowledged that water issues are difficult ones.

“Allocating water in the arid regions of the American West is often a zero-sum situation,” he wrote. It is important, he said, for courts to leave “to Congress and the President the responsibility to enact appropriations laws and to otherwise update federal law as they see fit in light of the competing contemporary needs for water.”

The ruling reverses a 9th Circuit Court of Appeals decision.

University of Utah law professor and a citizen of the Navajo Nation, Heather Tanana, says the decision means the burden will remain on tribes to secure their water.

“The help and assistance and I think the federal responsibility to help and assist would have gone a long way to filling that water gap,” she said.

More than a third of Navajo Nation residents lack clean water access in their homes.