When most Iowans hear about runoff, they think about the fertilizers and herbicides that run from farmland and into streams after rains. They don’t think about the dangers that a leisurely car wash can pose to water quality.
This spring, the state’s Environmental Stewardship Committee is asking organizers to limit the amount soap and other chemicals runs down storm sewers and into Iowa’s rivers and streams.
Rarely enforced, most weekend fundraisers are in violation of the Clean Water Act and water-discharge standards, said Bill Ehm, of the Iowa Department of Natural Resources’ Water Quality Bureau. The soap, scum and debris washing into the storm sewer does affect water quality.
“By the letter of the law, you can’t do it, but we aren’t chasing down fundraising groups and, hopefully, no one ever asks us to,” Ehm said. “We’re kind of splitting hairs here. Similar runoff occurs whenever there is a rainstorm, and the last thing we want to do is shut down kids trying to raise some money, but there is a greener way to go about it.”
The commission sent letters to organizations that often sponsor car washes asking them to consider locating their events off of paved surfaces. Runoff from parking lots usually drains into storm sewers.
That untreated water, soap, oil and grime eventually finds its way into streams and rivers. Commercial car washes are linked to the sanitary sewer system, and the water is treated at the Water Pollution Control Plant before it is released.
That greener way to do it is to avoid holding car washes near storm sewers and instead wash cars on permeable surfaces like on grass or gravel.
Ehm also suggested using phosphorous-free detergents to limit discharge of one of the top pollutants that plagues Iowa’s water quality, he told the Telegraph Herald.