The Walton Family Foundation will invest $20 million in the next two years to support the restoration and long-term health of the Colorado River, with the promise of more money to come.
"We are intending to spend upwards of $100 million within the Colorado River Basin from 2016 to 2020," said the foundation's senior program officer, Ted Kowalski.
The Walton Family Foundation was started by the founders of Walmart.
Kowalski said part of the investment will be used to help the state of Arizona manage its scarce water resources through proactive conservation programs.
"If entities can conserve water now, it will be better for the state of Arizona and it will be better for the Colorado River Basin," he said.
The foundation is also throwing its weight behind renewing Minute 319, an agreement between the U.S. and Mexico on water management that expires at the end of this year.
That agreement laid the groundwork two years ago for the release of water from the Morelos Dam near Yuma into the long-desiccated Colorado River Delta, a project that scientists and conservationists hailed as an ecological victory.