During July 2020, more than 5,000 people visited the wastewater treatment facility in Albany, Oregon. The main attraction was the 40-acre constructed wetland that cools up to 7 mgd of effluent from the activated sludge facility to meet regulatory requirements.

“Just think how unique it is that so many people would want to visit any part of a wastewater treatment plant,” says Joe Deardorff, natural treatment specialist for the city. But it’s not just any wetland. Named Talking Water Gardens, it’s a cascading series of nine ponds (cells) that provide habitat for wildlife, space for recreation and a laboratory for education.

Created in 2011 in response to the listing of salmon and steelhead trout on the endangered species list, and to meet state Department of Environmental Quality’s discharge temperature guidelines, the wetland was an alternative to more expensive cooling towers.

Fresh start

Rather than add to an existing pond structure that was part of a defunct plywood mill, the city started over and hired a landscape architect to design 40 acres of emergent wetlands. “Most of the facility functions like a wildlife preserve, but several sections are managed as Japanese healing gardens,” says Deardorff.

Large boulders, two 20-foot waterfalls, trickling water and crooked trees give the area a pleasing appearance. Some trees were left standing from when the wetland was flooded. Now dried, they provide perches for raptors. Primitive stop logs serve as control structures for water elevation through the cells.

“It presents a really tranquil area that benefits a whole lot of people,” Deardorff says. All the vegetation is native and supports native fauna. Cattail, bulrush, wapato, duckweed and Mexican water fern are the workhorses for cooling.

An ongoing project to install native trees and shrubs increases canopy cover for reduced sun exposure over the water. White alder, cedar, ponderosa pine, Oregon white oak and ocean spray complement coyote brush and black twinberry in that effort.

Space for walkers

More than 2 miles of gravel walking trails, some on tall berm plateaus and others at the water level, welcome visitors to the Talking Water Gardens. Amenities include benches at preferred viewpoints and doggy-bag stations. Notable wildlife includes great egrets, herons, bald eagles, otters, minks and beavers. Two federally listed threatened species, the western painted turtle and the western pond turtle, nest and bask in the gardens.

“That’s another really cool benefit to the gardens,” says Deardorff. “We are supporting one threatened species by controlling the temperature affecting the salmon and steelhead in the river, but we’re also providing habitat for a whole different threatened species.” The gardens are a hot spot for birdwatchers, too, and especially as a destination for the Audubon Society’s Christmas bird count.

A chain-link security fence separates the wetlands from the 12.3 mgd (design) Albany-Millersburg Water Reclamation Facility. Scott LaRoque, plant superintendent, says summertime flow averaging 5 mgd is pumped into the wetlands with two 16-inch Pentair Fairbanks Nijhuis vertical turbine pumps. 

There it is mixed with 2 mgd of effluent from a nearby metalworking firm, Allegheny Technologies, that was a financial partner in the construction of the treatment plant in 2009. Once mixed, water is split for gravity flow through four separate cooling trains as it makes its way through the wetlands for two days of retention time before outfall at the Willamette River.

“We adjust the flow occasionally to allow newly planted species to get established before we bring the water levels back up,” says LaRoque. “We don’t want to drown the emergents before they’ve had a chance to get out of the water.” 

Growing attraction

Each year, invasive species are removed and new seed mixes are tried in different areas. “Every year we draw down the water, then wait to see what sprouts out there the following season,” LaRoque says. “It’s a whole different approach than operating a conventional treatment plant.”

Bicyclists are allowed on the garden trail but are not encouraged.  Last year a decorative bike rack was installed at the entrance to encourage visitors to park and walk. Mounted on an 8-foot square concrete pad, the rack resembles elements of the gardens, such as a heron, dragonflies and bulrushes, all creatively flame-cut into the structure.

The number of visitors to the facility keeps increasing, says Deardorff. Formal tours of the plant and the gardens are given to students from grade schools and high schools each year. Colleges use the facility in their environmental education programs. A local watershed council uses it for programs about ecology and water quality.

“We’ve had many international visitors, too, from countries like Guatemala, Thailand, Vietnam, China and Mexico, just to name a few,” Deardorff says.