EASTON — The Tred Avon River should be cleaner in the future with the addition of new filters installed in Easton stormwater drains.
The work was done over the summer and facilitated by the Midshore Riverkeeper Conservancy, which obtained a grant from an anonymous Pennsylvania family foundation that has funded other projects on the Eastern Shore to pay for it.
The filters hang from inside and are lined flush along the length of the drains. They are designed to catch debris and trash, as well as oil-byproducts, phosphorus and sediment as it flows with water into the storm drain.
The drains flow directly to the Tred Avon River, which is listed as impaired by the Maryland Department of the Environment, Tim Junkin, executive director of the Midshore Riverkeeper Conservancy, said.
“It’s a way to filter the water before it gets into our rivers,” Junkin said. “They’ve been used in a number of towns with really good results.”
The 255 Ultra-Urban Filters were manufactured by AbTech Industries and installed by Andrew Frase Excavating LLC, from Trappe, in 52 stormwater drains spread across town.
According to the local Riverkeeper group, the unique micro-porosity of the sponge inside each filter allows a hydraulic flow rate of more than 250 gallons per minute and has proven effective in removing more than 80 percent of hydrocarbons, or oils, and total suspended solids. The filters also have an overflow capability to eliminate potential street flooding in case a filter is plugged.
Junkin said that in order for the filters to fit in a storm drain and be flush to work properly, the drains have to have a few feet of vertical leeway.
“Some of them had old gas pipes running through them that blocked it, so we had to find the ones that were suitable,” he said. “It took a while to do that.”
Junkin said stormwater runoff is a significant source of river pollution, so removing hydrocarbons, street chemicals, phosphorus and sediment with the filters “will hopefully help make a difference.”
Mayor Bob Willey said the town is pleased to try the filters as another step to clean area streams and rivers.
Willey said the town has been “catching a lot of grief” from runoff from shopping center parking lots down near St. Michaels Road and the Easton Parkway.
“If you look at some of the streams around town where you’ve got Styrofoam cups, food wrappers and all that — a lot of this stuff now is going to be picked up before it gets to the streams,” Willey said.
Beyond stopping trash from initially entering streams and rivers, stopping hydrocarbons and phosphorus from entering them is a plus, Willey said.
The expected lifespan of the filters is between three and five years, and the town intends to replace the filters as needed over revolving budget cycles.
Easton’s public works department has constructed a way to clean the filters — an extension from a street sweeper that serves as a vacuum to suction out the trash and debris from the filters.
According to Junkin, Talbot County has expressed interest to use the filters in other towns, and the Midshore Riverkeeper Conservancy would welcome the opportunity to do the work in other areas.