Restoring the Colorado River Delta

How building binational support brought water, trees, funding, and birds back to the Colorado River Delta.

By Jennifer Pitt, Colorado River Program Director, Audubon
Verdin. Photo: Lisa Langell/Audubon Photography Awards

Today, the United States and Mexico, through the International Boundary and Water Commission (IBWC), released an implementation report documenting the first environmental progress under Minute 323, a binational Colorado River agreement adopted in late 2017. The report documents more than $3 million spent and nearly 7,000 acre-feet water delivered for habitat restoration during the first year of the agreement. The story behind these numbers is remarkable.

First, there’s the fact that restoration is taking place at all. Not long ago, the United States and Mexico were locked in a bitter battle over Colorado River management, disputing lining of a canal that saved water for the United States and depleted water availability in Mexico. Today the two countries are collaborating to put habitat back in the Colorado River Delta—an extraordinary success of diplomacy that stands out at a time when U.S.-Mexico relations are otherwise fraught.

Throughout the 20th century, both countries developed water for farms and cities that desiccated the Colorado River Delta throughout its 250,000 square mile watershed. A vast expanse of wetlands and riparian forests disappeared as the river ceased to flow through its final hundred miles towards the sea.

Now, more than 1100 acres thrive with native trees and wetlands vegetation. In 2018 alone, restoration crews cultivated more than 50,000 native plants in on-site nurseries before planting them—significantly hard labor in the desert sun.

It takes extraordinary effort to make this landscape bloom again. Hard-working non-governmental organizations (NGO) restoration crews spend countless days in the hot sun preparing lands and planting trees. An NGO environmental water trust cooperates with the vast Mexicali Irrigation District to ensure those trees are watered. A binational team of scientists travels the area repeatedly to collect data on the ecological and social impacts so that the effort might improve in the future. An impressive, binational collection of organizations, including federal and state agencies, NGOs, and universities work together to coordinate the work and ensure dollars and water are available to support it.

We know from past monitoring reports that birds are returning—species diversity is 27 percent greater and populations are a stunning 80 percent greater in restored sites along the Colorado River in the delta when compared to lands not yet restored. Birds recently spotted include: Albert’s Towhee, Ash-throated Flycatcher, Blue Grosbeak, Black Phoebe, Black-tailed Gnatcatcher, Cactus Wren, Crissal Thrasher, Gila Woodpecker, Hooded Oriole, Ladder-backed Woodpecker, Song Sparrow, Vermillion Flycatcher, Verdin, Western Kingbird, and Yellow-breasted Chat. We expect more good news when the IBWC publishes the next monitoring report later this year.

Originally appeared on, May 7, 2020