By MaryBeth Matzek
New storm-water regulations are stacking up faster than the methods to comply, but a public-private research partnership is working to counteract that imbalance as quickly as possible.
The Environmental Protection Agency and Wisconsin Department of Natural Resources recently developed new regulations to improve storm-water quality in urban areas, requiring further reductions in pollution from state municipalities, businesses and property owners.
Biofiltration, which is the use of an engineered soil layer to filter storm-water pollutants from runoff, is a popular method to comply with such regulations, but questions remain about how best to use the technique.
To answer those questions, three Neenah businesses teamed up with the Wisconsin DNR and the United States Geological Survey to test several biofiltration options. The research project will help determine the minimum thickness of engineered soil needed to cost-effectively remove storm-water pollutants, said Nick Vande Hey, senior project engineer at Neenah-based McMahon Associates Inc., one of the companies involved in the project.
SCA Tissue North America LLC and Miron Construction Co. Inc. The three devices have different engineered thicknesses — 12 inches, 24 inches and 36 inches — and contain a mix of compost and sand.
“The devices will be monitored to see what the different depths do in regard to filtration,” Vande Hey said.
“For example, if the monitoring shows 12 inches filters just as well as 36 inches, that is helpful to know since digging a hole 12 inches deep is cheaper than going 3 feet down.”
Essentially, the partnership is seeking a new standard for the industry, he said.
The Geological Survey and Wisconsin DNR installed the monitoring equipment at the sites in fall, Vande Hey said. The equipment documents rainfall, runoff volumes and pollutant removal at each site.
For McMahon Associates, which provides engineering, architectural and design/build services, participating in the project was a natural fit, Vande Hey said.
“This is something a lot of people are concerned about, and we thought this research project was a great way to find a cost-effective solution to the problem,” he said. “It’s all about sustainability.”
The other two companies involved also are champions of improving sustainability. Miron recently completed an expansion project at its Neenah headquarters that incorporates a wide variety of energy-efficient improvements, including the biofilter installation. Among SCA Tissue’s green efforts is the installation of a wind turbine on its property to help lower electricity costs.
The DNR plans to examine the biofiltration samples this summer, and the project’s results may be published by the end of the year, Vande Hey said.
“It’s something we’re eager to see,” he said.