Heavy Rains Cause Chemical Runoff Worries For Water Companies

May 15, 2017

Experts are cagey about whether farmers or weekend warriors pose more of a threat to water systems from the chemicals they use.
Credit Peter Organisciak / https://www.flickr.com/photos/organisciak/525843127

At least one Indiana water company is warning its customers to be mindful of the chemicals they put on their lawns.

Indiana American Water issued a press release saying recent heavy rains have made it more likely that pesticides and other chemicals would flow from urban lawns into municipal sewer systems.

Once they get there, Office of the Indiana State Chemist pesticide administrator David Scott says they can be hard to treat – especially if the chemicals dissolve during heavy rains like Indiana has seen in recent weeks.

Scott admits farms are also a source of toxic runoff, and says he can’t say whether urban or rural land creates more pollution. But he says if lawn care companies are careless, they pose a significant threat.

“If you’re going to leave pesticides or fertilizers on hard surfaces in urban areas, I think that has a larger potential of having materials go directly into the stormwater,” Scott says.

Scott says the Environmental Protection Agency mandates training for the application of some chemicals, so fewer poisons wind up in drinking water.

And though some companies monitor their water several times daily – especially after heavy rains – Scott says it’s not uncommon for downpours to overwhelm treatment systems, resulting in discharges of chemical-filled water into lakes, rivers and streams.

“A lot of the water suppliers are experienced enough they almost can tell you based on the amount of rainfall and the amount of research that’s been done, they know when they’re going to have to up their treatment capabilities," Scott says.

So far this spring, the Indiana Department of Environmental Management has received nearly 100 water overflow reports from more than a dozen different treatment locations.

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