Stormwater is a toxic cocktail of road grime, grease, tire wear and any litter small enough to slip into storm drains.
Thursday marks the 40th anniversary of the Clean Water Act. When it first took effect, stormwater pollution was not the top priority. What’s known as “point source pollution” — dumping of toxic pollutants from a particular, often industrial site — was the first focus. But in the decades since, stormwater pollution, also known as “non-point source pollution,” has taken the lead when it comes to carrying the most contaminants to U.S. waterways. About 40 percent of U.S. rivers, lakes, and estuaries are not clean enough for fishing or swimming because of pollution from runoff.