A plan to address a shrinking supply of water on a river that serves 40 million people in the U.S. West is headed to President Donald Trump.
The U.S. House and Senate approved the Colorado River drought contingency plan on Monday.
Arizona, California, Colorado, Nevada, New Mexico, Utah and Wyoming spent years negotiating the drought plan. They aim to keep two key reservoirs from falling so low they cannot deliver water or produce hydropower.
Mexico has promised to store water in Lake Mead on the Arizona-Nevada border if the U.S. legislation is approved by April 22.
State water managers and federal officials have cited a prolonged drought, climate change and increasing demand for the river's flows as reasons to cut back on water usage. The agreement runs through 2026.
In the lower basin, Arizona and Nevada would keep water in Lake Mead when it falls to certain levels. The cuts eventually would loop in California if Lake Mead's level drops far enough.
The measure approved Monday reflects language proposed by the states but also includes a section that says the implementation of the drought plan won't be exempt from federal environmental laws.
The Imperial Irrigation District in California, which holds the largest entitlement to Colorado River water, and environmental groups had raised concern about draft language they took to mean federal laws like the National Environmental Policy Act and the Endangered Species Act would be disregarded.