(Courtesy of the Sonoran Institute)

The Colorado River (top) fails to reach the Sea of Cortez.

For the first time in many years, the Colorado River is expected to reach the Sea of Cortez in Mexico on Thursday. 

It's the result of something called a pulse flow, a large release of water into the Colorado River that began in late March. It came about thanks to the work of a coalition of nonprofit organizations in the U.S. and Mexico.

This historic reconnection is important, said Jennifer Pitt of the Environmental Defense Fund, "but I think it’s more important to us as human beings and our sense of what is right for our river, then it is in terms of a particular ecological goal that I could express to you."

In general, Pitt explained, the goal of the pulse flow is to reawaken the delta, which hasn’t regularly seen water in more than 50 years.

She said it could spur the growth of trees and restore habitat for many species of birds. The pulse flow is meant to simulate floods that used to sweep through the delta every spring.