There are huge benefits to the rain gardens at the two wastewater treatment plants in Fayetteville, Arkansas, says Tim Luther, operations manager for contract management firm Jacobs Engineering Group.

More than 135,000 square feet of turf has been converted to rain gardens, bioswales and managed naturalized buffer areas that support the city’s commitment to sustainability. “We are using native vegetation and managing areas at our treatment plant sites to promote natural growth and reduce lawn maintenance,” Luther says. “Done in the right way, you can get rather large areas of landscape that require zero irrigation.”

Diverse vegetation

Fayetteville’s West Side Wastewater Treatment Facility (16 mgd design, 10 mgd average) has the larger rain garden area; nearly 2 acres are dedicated to Ozark-only plants. They complement the adjoining Woolsey Wet Prairie Sanctuary, a 44-acre wetland and publicly accessible wildlife area that is integral to the plant’s operation.

More than 50 species of native vegetation have been planted in the rain garden and bioswale areas to minimize maintenance, improve aesthetics, increase biodiversity as protection against disease or pest outbreaks, and improve stormwater uptake.

Native plants such as splitbeard bluestem, river oats, pink muhly grass, purpletop tridens, and switchgrass are mixed with wildflowers such as milkweed, dogbane, purple coneflower, black-eyed Susan, and sunflowers. Strategically placed native trees and bushes include black gum, eastern redbud wafer ash, Ozark witch hazel, possum haw and winterberry.

Still expanding

The rain gardens at the Paul R. Noland Wastewater Treatment Facility (17 mgd design, 12.6 mgd average) are a work in progress. “They are not entirely maintenance-free,” says Jeff Hickle, environmental projects specialist. “Each year we have project areas that need to be maintained, and nearly every year we create new ones, typically around 15,000 square feet.”

Rain garden maintenance and expansion are part of the utility’s community outreach and public education. Each year the staff engages community volunteers who spend a day weeding and cleaning the sites, gathering and planting native seeds and plants, improving existing gardens, and creating new ones.

“We made a commitment in 2013 to learn what’s required to increase each species’ density, improve plant diversity, and engage volunteers to collect native seeds from nearby areas and then broadcast them in the rain gardens,” Hickle says. “It’s a good fit for our maintenance schedule, supports out team’s mission as environmental stewards and brings a lot of good attention to the city’s commitment to be a resource-efficient community.”  

Grant support

The rain garden project began in 2009 with a design by The University of Arkansas Community Design Center, part of the university’s school of architecture. The purpose of the original garden was to establish civic presence to an industrial area through habitat restoration and education.

Since then, grants from the Beaver Watershed Alliance and the Illinois River Watershed Partnership have largely funded the rain gardens. Goals to restore a natural habitat and attract butterflies, birds and other wildlife are being met, Hickle says.

Tim Nyander, utility director encouraged pursuit of the grants and supports other city initiatives. For example, Fayetteville is a signatory of the National Wildlife Federation Mayors’ Monarch Pledge. More than 25 mayors across the nation have pledged to create and sustain habitat for monarchs and other migratory pollinators. 

“Rain gardens are great place for the milkweed and other good pollinating wildflowers that create good habitat for monarchs,” Hickle says.

Climate-friendly

The rain gardens also reflect the city’s commitment to sustainable landscapes. “We want to promote spaces that are good for mitigating heat island effects, offer climate resiliency, and aid in carbon sequestration by not using fossil fuel during mowing,” Hickle says.

Luther adds, “We’ve been at this for nearly 10 years, and we have had a learning curve. When it’s done right, you gain more benefits over time, like improved soil quality, better stormwater infiltration, improved habitat for butterflies and wildlife and, of course, the aesthetics and community involvement.”