Small, green leaves on the willows dot the banks of a newly dug channel, and blades of grass poke through the dry, sandy soil—signs of an ecosystem returning to a healthier equilibrium.
“Did you see the fish?” asks Sarah Hurteau during a recent tour of the re-engineered effluent outflow in Corrales, where the Harvey Jones Channel meets the Rio Grande.
The secret to the resurgence of life on the riverbank: “Just add water,” the climate change program director of the New Mexico chapter of The Nature Conservancy tells SFR.
The Nature Conservancy partnered with local governments and other environmental groups to transform the site of Rio Rancho’s wastewater outfall—which averages 4 to 5 million gallons of treated effluent per day—into a wetland habitat.
The result is a bioswale, a series of wide channels lined with vegetation, that funnels the wastewater back into the Rio Grande.
The constant flow of water from the city supports the growth of plants, fungi and bacteria that help filter the water before returning it to the Rio Grande, all the while supporting a habitat for native species.
“Most of the vegetation that was here was either invasive or dead,” Hurteau says of the landscape before the renovation. She’s been visiting this area for years, but last Thursday was the first time the longstanding willows looked green.
Teams with Rio Grande Return, a nonprofit that supports river health in New Mexico, harvested and transported the willows and young cottonwood trees that line the newly excavated channels from the Bosque del Apache National Wildlife Refuge. Crews also removed 18,000 cubic yards of soil from the site.
The treated wastewater, which previously flowed directly into the Rio Grande, now meanders through vegetation and boulders, slowing the flow and enabling more water to infiltrate the soil and support the plant life filling in around the wetland.
In the face of climate change, engineered solutions that make the most of water are necessary, explains Hurteau.
“When it’s coming, it’s coming all at once,” she says of precipitation in New Mexico, “with lots of time in between when it’s dry.”
The pattern points to a need to conserve water and prepare for large storm events. The project includes a high-flow channel to accommodate surges in water levels from the Harvey Jones Channel, which collects and directs the flood water from Corrales into the Rio Grande.
Historically, urban areas in New Mexico relied on infrastructure to quickly remove water and, in turn, prevent flooding. Combined with the extensive development of impervious surfaces (roofs and pavement), these factors have contributed to drying of the landscape and the unhealthy expansion of arroyos in urban areas.
The City of Santa Fe has invested in green stormwater infrastructure such as rain gardens and permeable pavement, two practices that capture rain where it falls and prevent excessive amounts of stormwater from collecting pollutants on roadways and carrying those downstream.
The benefits of green stormwater infrastructure can simultaneously conserve water, Hurteau says, and prevent the transportation of pollutants and help support ecosystems that make cities more livable.
“We need to be thinking about the city of the future we want to create,” she says, noting that with increasing temperatures, cities need to leverage stormwater to sustain more trees in urban environments. By providing shade, trees provide a cooling effect that can reduce daytime temperatures in a city by up to 10 degrees.
Hurteau says green stormwater infrastructure projects and other conservation methods, like the use of cisterns to collect rainwater, can support the growth of more trees and green spaces in urban areas.
The project cost $700,000, with contributions from the City of Rio Rancho and The Nature Conservancy, she tells SFR.
Though her group doesn’t have similar projects planned for development, Hurteau says the next step is to explore other areas further upstream on the Rio Grande to look for other effluent sources that could result in similar projects.