Updated

Colorado River water has begun pouring over a barren delta in northwest Mexico, the result of a landmark agreement between the U.S. and Mexico that is being celebrated Thursday.

The gush of water in Mexico is an effort to revive the last 70-mile stretch of the river into the Sea of Cortez, which dried up decades ago.

The river's most southern dam — Mexico's Morelos Dam, near Yuma, Ariz. — on Sunday began unleashing 105,392 acre-feet of water, enough to supply more than 200,000 homes for a year. The one-time release is expected to last until May 18.

Farms, businesses and homes in seven U.S. states — Arizona, California, Colorado, Nevada, New Mexico, Utah, Wyoming — rely on the Colorado River, as do the Mexican states of Baja California and Sonora.

In 2012, the two countries that share the river water agreed on ways to share the pain of droughts and bounty of wet years, a major amendment to a 1944 treaty. Part of that agreement called for restoration of the Colorado River delta.

"Never before have we deliberately sent water below the Morelos Dam ... to benefit the environment," Jennifer Pitt of the Environmental Defense Fund, who helped negotiate the one-time flood, wrote on her blog this month. "By abandoning the old framework of 'who gets what' and establishing cooperative management of our shared resource, the U.S. and Mexico are achieving benefits for communities and nature alike."

The one-time release of water was achieved through water conservation projects by the U.S. and Mexico, according to the International Boundary and Water Commission. Officials from the U.S. and Mexico were scheduled to be at the Morelos Dam on Thursday for an event to mark the restoration effort.

Experts will monitor the flood to determine its effects on the environment. Conservationists hope the water will bring back trees, wildlife and aquatic life that were once abundant in the region when it was teeming with water decades ago.

Follow us on twitter.com/foxnewslatino
Like us at facebook.com/foxnewslatino