Thanks to a landmark agreement between the United States and Mexico, the parched Colorado River Delta will get a rejuvenating shot of water this spring for one of the first times in five decades, just in time for World Water Day on March 22.

On March 23, 2014, the gates of Morelos Dam on the Arizona-Mexico border will be lifted to allow a "pulse flow" of water into the final stretch of the Colorado River. Officials and scientists hope the water will help restore a landscape that has long been arid but that once supported a rich diversity of life.

"The pulse flow is about mimicking the way the Colorado River flowed in the springtime, thanks to snowmelt from the