Just below a bridge in north Tempe, black-crowned night herons wade through fluffy clouds of bright green algae clinging to the Salt River’s muddy bottom.
Families of ducks waddle around, snatching the heads off of cattail reeds. Native plants such as cottonwood and willow trees, Colorado River hemp and Valley red stem poke out of the swampy water.
The riparian area under the McClintock Drive bridge just north of Rio Salado Parkway is a snapshot of what the Salt River could have looked like hundreds of years ago and is the goal of some restoration projects currently in the mix.
"Just add a little water and it will grow," said ecologist Julie Stromberg.
Stromberg, an associate professor in the School of Life Sciences at Arizona State University, studies the wetland with a group of graduate students. They started exploring what she calls "uncharted territory" beneath the McClintock Drive bridge in the spring of 2004.
"No one has ever done a complete inventory of all the plant species of the Salt River," Stromberg said. "Basically we don’t know all the plants that are out there."
The group has found many indigenous plants as well as such urban varieties as Chilean mesquite trees that arrived via a storm drain.
Few of these riparian habitats exist along the Salt River because most areas lack a constant flow of water throughout the year.
The Tempe Marsh, as this spot is dubbed by bird-watchers, was just that lucky. A combination of effluent waters replenishing the area from Mesa’s water treatment facility, runoff water and an Arizona Department of Transportation storm drain led to the birth of the small biological miracle more than six years ago.
What’s happening naturally under and near the bridge is what two other projects on the Salt River, the Rio Salado Project and the Va Shly’ay Akimel, hope to accomplish — restoration of natural habitats.
Organizers of the Rio Salado Project, which runs from the west dam of Tempe Town Lake to Priest Drive and from the east end of the lake to a grade control system near the McClintock Drive bridge, have begun planting native plants such as cottonwood and willow trees in and around the Salt River. The project should be completed by early 2007 at a cost of about $8 million.
The difference between what’s happening in the Tempe Marsh and the Rio Salado Project is that the Rio Salado plants will be irrigated "intermittently" for two years and then allowed to survive on their own, said Nancy Ryan, senior planner for the project, while the riparian areas receive constant water flow year-round.
As an example of what organizers hope to replicate, Ryan cited the LoPiano Mesquite Bosque Habitat near Papago Park, which was constructed in 1993 and is now considered a success. Native plants reintroduced to the area now survive on their own without water sources provided by the city.
"It started out irrigated and now it doesn’t have water. It’s what we hope to see of this habitat 10 years from now," Ryan said.
Some, such as ecologist Stromberg, are wary of the projects’ impact.
"Generally, I think it would be a good idea to be concerned and pay attention to what’s there now and work around it to some degree," she said, citing rich soil surrounding the river.
Resources such as seed banks along the river, she said, already have the potential to re-create natural habitats if they are just allowed the necessary water.
The habitat manager for the Mesa office of the Arizona Game and Fish Department, Russ Haughey, agrees.
"I’m a little skeptical and a little disappointed in some of the Rio Salado Project," he said.
"It’s really hard for people to create habitats. So many things can go wrong. However, if you just add water and walk away, you get a riparian habitat."
Tempe Marsh, which attracts bird-watchers from throughout the country, is between the two other Salt River projects. So for the moment, many bird-watchers trespass on the land owned by Tempe, the Salt River Pima-Maricopa Indian Community and ADOT to get the best view possible.
"We call this little section ‘the orphan,’ " said Diana Stuart, environmental planner for the Flood Control District of Maricopa County.
"Sooner or later it will get a parent — we hope it will be part of the river rehabilitation projects in the future."
Maricopa County Vector Control takes care of the mosquitoes, the county Flood Control District cleans up debris and salt cedar trees and the Game and Fish Department monitors the critters, including muskrats and the occasional bobcat.
It’s a partnership that Stuart says is worth it.
"Nature took its course and created this natural habitat," she said. "If we were to try to build (the habitat) from scratch, it would cost millions and millions of dollars."