The Return of the Colorado River to the Sea
Because of thirsty towns and even thirstier farmland, not all rivers reach the sea. The Colorado River has long been the poster casualty of this phenomenon—that is until last week, when for the first time since 1998, the delta reached its final destination, the Gulf of California, just as nature intended.
Though temporary, the change could mark the beginning of the 1,450-mile river’s restoration. A group of scientists and an agreement between Mexico and the U.S., which for years was in violation of a treaty guaranteeing Mexico a certain amount of flow at the border, made the landmark reunion possible.
Just in time for World Water Day in March, the Morelos Dam on the Arizona-Mexico border was opened to allow a “pulse flow” of water to refresh the parched expanse of the Colorado River Delta. Scientists designed the move to mimic how the river once flowed, when snowmelt from the Rocky Mountains reached the delta most years in the spring until dams diverted the water to places like Las Vegas and Los Angeles.
Eight weeks after the facilitated pulse flow, the Colorado River touched the gulf (also known as the Sea of Cortez). National Geographic reports that scientists didn’t expect the pulse flow to achieve the historic result, which they describe as a “wonderful bonus.”
Still, the stream of water amounted to less than 1 percent of the river’s pre-dam flow. Researchers are now working to increase the amount in future flow releases.
“[The reunion shows that] improving estuarine conditions in this upper part of the estuary is possible if restoration efforts continue in the future,” Francisco Zamora, director of the Colorado River Delta Legacy Program, told National Geographic.
A recent hike in awareness is promising. Thanks to organizations like Change the Course and, in part, to Robert Redford and Will Ferrell, more people have been paying attention to the parched river delta. With enough effort, the Colorado River could regain its majesty. That would be good news for Mexico, as well as for the birds, fish, and other wildlife that the river once nurtured.