Can you name the river that rises in a US state at the western edge of the Great Plains and travels 1,400 miles, passes through five US states and Mexico, and is being celebrated for an agreement between the two countries that includes environmental benefits for the first time ever?

The delta of that river will be flooding this week for the first time in years. Can you name it?

It's the mighty Colorado, the river that carved out the Grand Canyon over millions of years. Much more recently the Colorado's been drained by irrigation or stopped in its tracks by dams. Barely a drop reaches the river's delta in Mexico anymore. But just a few days ago, US and Mexican officials released a massive pulse of water from Lake Mead in Nevada.

And the flood is now moving south toward the Colorado delta.

Taylor Hawes, Colorado River program director for the Nature Conservancy, says the idea is to mimic the seasonal surges of years past.

"In the spring we get these spring floods," she says. "They help restore the environment and help trees bloom and move seeds around. This is part of a larger agreement between the US and Mexico that includes a lot of other benefits for farmers in Mexico and water for the delta, which has not seen water regularly since the 1960's, since Lake Powell was finished."

Hawes says the artificial flood is an experiment in both river restoration and US-Mexico cooperation.

"We've so over-used the Colorado River throughout the US and Mexico that no water makes it to the delta anymore and so the delta has dried up," Hawes says. "There are a few pockets where there's healthy cottonwoods and willows for birds but this region's been reduced to about 10 percent of its former size. So we're just trying to make sure there's healthy riparian forests for birds and wildlife in this region, but we have to do it a little more creatively than if Mother Nature were doing it."

Hawes says right now the water is seeping more than surging. But by the weekend, she says the flow might be enough for scientists to raft along a stretch near the international border.

And in a few more days, they're hoping the Colorado might flow all the way to its mouth at the Gulf of California for the first time in years.

"It just chokes me up to see this river that has not been through this area is more than 17 years, kind of working its way to the ocean like it should, like it was meant to do," she says. "Just seeing a river getting to be a river again, I just want to celebrate it."

UPDATE: A previous version of this story indicated that the Colorado River starts in Wyoming. The river actually starts at the La Poudre Pass Lake in northern Colorado. There are tributaries in Wyoming that feed into La Poudre Pass Lake. Thanks to our listeners pointing this out.