As you drive out East State Street to go home or shopping, you likely have noticed the many recent street improvements to enhance the flow of traffic in this part of Athens. What you may not have noticed is the new bio-retention basin.
Or maybe you have seen it but don’t know what it is. And what is a bio-retention basin anyway?
As you head east, it’s on your right at the East State and US Rt. 33 interchange. That big bowl-like depression in the ground with the shrubs and ornamental grasses in the middle – that’s the basin.
It’s like a rain garden but bigger. And it involves engineering design and an overflow pipe.
The purpose of the bio-retention basin is to reduce runoff to the Hocking River. This works by allowing rainwater, aka stormwater, to infiltrate the ground instead of running off.
“There is a drain in the center that is connected to the city’s storm sewer system,” explained Jessica Adine, assistant city engineer. “If there is a significant rain event and the ground is already saturated, the drain would allow stormwater to flow into the city’s system.”
The U.S. Environmental Protection Agency considers rainwater – or more accurately what it’s carrying – to be a significant source of pollution. In this case, rain and snow-melt from the street and highway could carry oil, grease, gasoline, dust from tires and brakes, and more.
Athens is required by the Ohio EPA to regulate stormwater inside the city limits. The mandate led to adoption of a Stormwater Management Program.
Teresa Caldwell, conservation education coordinator for the Athens Soil and Water Conservation District, was hired to develop and implement the program.
“Plant selection is very important to the operation of the bio-retention basin as well as its appearance,” Caldwell said. “Plants can do a lot toward reducing the quantity of the stormwater in the garden since a working garden should drain in 24 to 36 hours after a rainfall.”
The plants at the basin were also selected for their beauty. Most of them will provide blooms and fruit that are attractive to pollinators and other wildlife.
“They also have the ability to survive in extreme conditions, very wet or very dry, which is often the case with rain gardens,” added Caldwell. “The plants selected for this project were all natives to this region, with the exception of the some ornamental grasses which were added for their interest and color.”
The plantings were arranged by their size at maturity. At the center is the American highbush cranberry (Viburnum trilobum).
“Growing from 10 to 15 feet tall, (the highbush cranberry) has lovely blooms in the spring and red berries loved by wildlife in the fall,” Caldwell said.
Dresden Landscaping served as subcontractor for the basin project, and the company was paid approximately $80,000, according to Adine.
“The planting area will need to be weeded, and the plants cared for, but the system shouldn’t need any special longterm care,” she said.
The East State Street basin is not the first construction of its kind in Athens. The city installed smaller bio-retention boxes along West Union Street (near Depot Street) in 2014 as part of a stormwater project funded by the Ohio EPA, Adine said.