An open house from 9:30 to 11:30 a.m. Saturday will offer residents a chance to hear about the changes of how storm water is handled in Delaware’s Blue Limestone Park.
The city of Delaware received a grant from the Environmental Protection Agency to reduce how storm water runoff filters through the park and into the groundwater aquifer and Delaware Run. Public utilities director Brad Stanton and Upper Olentangy watershed coordinator Kristin Piper will be on hand answer questions about the improvements, which were completed in September.
“I know some people have seen what’s gone on out there, but don’t understand what exactly everything does there,” Piper said.
Among the improvements were installing pervious pavement, which is 10,000 square-feet of porous material in some of the parking lots. According to the city, when rain falls, the droplets will seep through the pavement and a rock-filled bed beneath the parking lot, and through the soil below.
“The water will infiltrate through that material and recharge the groundwater aquifer, as opposed to it just running off and carrying the pollutants and impurities into the lake and Delaware Run,” Piper said. “Now we’re trying to improve that water before it reaches those waterways.”
There are also bioretention areas in the park, also known as rain gardens. These five depressions catch the storm water runoff with wetland plants that can absorb rainfall.
Another improvement is called a bioswale.
“Basically it’s just an engineered open channel, and it’s designed to remove sediment and pollutants from the storm water runoff,” Piper said. “The plants take up water and can use some of those nutrients, such as excess fertilizer that would otherwise just run into Delaware Run or the lake and cause algae.”
In general, it is better for excess storm water to go into the ground than to run off into waterways.
“Before there was a lot of development, the water would just hit the ground and be absorbed,” Piper said. “Now we have hard surfaces like roofs and driveways. Everything flows into pipes, and then all those pipes discharge into the river. The park improvements take it more of a natural setting.”
The improvements will not eliminate flooding, she said.
“Getting rid of some of those impurities that are on lawns and pollutants will benefit our water quality.”
Gary Budzak may be reached at 740-413-0904 or on Twitter @GaryBudzak.