'Rain Gardens' Work to Capture Stormwater Runoff in Roswell

Submitted by the city of Roswell

We’ve all seen water rushing across a parking lot after it rains, and we’ve probably not thought much about it. But stormwater flow across hard surfaces like parking lots and roadways is a key way that pollutants enter our local waterways.

And it’s one of the main reasons the city of Roswell has built innovative structures called rain gardens to improve the water quality of Crossville Creek, a stream that runs through Roswell Area Park.

A rain garden is a shallow depression or basin in the ground that is designed to capture and filter stormwater runoff and the pollutants it carries. Rain gardens are planted with deep-rooted native plants, grasses and shrubs to remove sediments and pollutants before they enter our groundwater and waterways.

“Rain gardens mimic the natural absorption and pollutant removal that happens in a forest, meadow, prairie or other natural area,” said Alice Champagne, water resources manager for the city of Roswell. “It’s a low-tech, effective, sustainable, and aesthetically beautiful way to safeguard our waterways.”

The city targeted areas within Roswell Area Park because many of the park’s impervious areas (parking lots) drain directly into Crossville Creek. The creek is included on the Federal Clean Water Act’s list of impaired waterways in Georgia for fecal coliform bacteria.

“When we found out Crossville Creek was impaired, we knew we had to come up with a way to protect that waterway from further damage. We also wanted to reduce the volume and velocity of stormwater contributing to stream bank erosion and flooding,” Champagne added. “Rain gardens are called a Best Management Practice, or BMP, in our line of work because they address all those concerns quite effectively.”

Four rain gardens have been created throughout the park: entrance road parking lot, pedestrian path near turf ball fiend and two areas in the football field parking lot

The total project was just under $200,000, which included a partial grant from the federal government for 55 percent of the cost.

Roswell’s Water Resources Division plans to continue to monitor downstream of Roswell Area Park and compare new data to previous data. In addition, rain gardens will be incorporated into future City projects wherever appropriate.

The city will be celebrating the completion of its new rain gardens during a ceremony at Roswell Area Park on Thursday, Nov. 6, 2014 at 11:15 a.m. The ceremony will take place near the first parking lot on the left, immediately after entering the park at 10495 Woodstock Road. Residents are welcome to attend and learn more about the rain gardens.

“We’re placing informational signs at the rain gardens to help educate our residents and visitors,” said Champagne. “We’re excited for the community to see these gardens and the improvements they will make. We can all be proud of this long-lasting solution.”

(Photo credit: city of Roswell)