As water supply continues to raise alarm bells across the American West, Sen. Mark Kelly introduced a bill that would allow central Arizona’s Colorado River Indian tribes to give portions Colorado River shares to other parts of the state. 

The Colorado River Indian Tribes are a single tribal nation made up of more than 4000 Chemehuevi, Mojave, Hopi and Navajo members who live along the river in California and Arizona. 

The bill comes amid historic low levels in Lake Mead and as Arizona faces a harsh water future. The state is set to take mandatory cuts to its share of Colorado River water starting in January.

Like other tribes in Arizona, the Colorado River Indian Tribes have a pre-set share of water rights and, under the legislation, could lease some of those shares to other cities. Both Tucson and Phoenix metropolitan areas rely on that water.

In a statement, the tribe said the legislation would protect Arizona, and, for the first time in more than a century, allow the tribe to fully benefit from its water rights.