Arizona Department of Water Resources

The Santa Cruz River near its head waters in the San Rafael Valley.

More than two years ago, Tucson brought flowing water back to a dry portion of the Santa Cruz riverbed, and the ecosystem has made a fast recovery.

The river was revived with treated wastewater, and according to media reports, wildlife responded quickly.

People showed up to witness the flows the day they started. Kari Hackney of the Tucson Audubon Society says that the river ecosystem has allowed native trees to thrive, which has been beneficial to birds.

“It’s pretty wild for us doing our work in the desert. We’re not used to working next to water," she said. "So we’ll be taking our lunch break, and there will be birds

hunting in the river, great egrets. They’ll be hunting right in the river, right where we’re working.”

She says the change has brought predatory species, such as owls, as well as migratory birds attracted to willows and cottonwoods.