Today, Food & Water Watch, Iowa Environmental Council and the Environmental Law & Policy Center sued the Environmental Protection Agency (EPA) over its July 2025 decision to, without scientific justification, delist seven impaired waterways from Iowa Department of Natural Resources’ 2024 303(d) Impaired Waters List. Groups are asking the Court to order that EPA relist the waters or, at the very least, issue a final determination that explains the delistings.

Just months earlier, the EPA had determined these waters–which include segments of the Cedar, Des Moines, Iowa, Raccoon, and South Skunk Rivers that supply drinking water to hundreds of thousands of people–are contaminated with levels of toxic, cancer-linked nitrates exceeding federal safety thresholds. A recent analysis of the Des Moines and Raccoon Rivers found that more than 80% of the rivers’ nitrates stem from industrial agriculture, including factory farms and the intensive row cropping that feeds them.

Food & Water Watch Staff Attorney Dani Replogle said: “Trump’s EPA is enabling an enormous public health crisis in Iowa. While factory farms pollute hundreds of thousands of peoples’ drinking water with dangerous levels of toxic nitrates, EPA is hanging Iowans out to dry — we cannot allow that to happen. EPA’s irresponsible about-face on Iowa’s nitrate pollution crisis will not stand in court.”

Nitrate, linked to birth defects and cancers, is found in synthetic fertilizers and factory farm waste. A recent Iowa Environmental Council and Harkin Institute report found that Iowa has the nation’s worst waterway nitrate contamination. Iowa has the second-highest cancer rate in the nation and is one of only three states with rising cancer rates.

Environmental Law and Policy Center Senior Attorney Josh Mandelbaum said: “At a time when Iowans were facing a water quality crisis that led to the first ever lawn watering ban in the Des Moines metro, EPA removed waters from the impaired waters list. EPA’s actions were out of step with the experience of Iowans and the law. It’s time for EPA to course correct and come up with a real plan to clean Iowa’s dirty waters.”

Iowa Environmental Council General Counsel Michael Schmidt said: “Iowans in cities, towns, and rural areas face worsening health problems due to nitrate contamination. Pretending the problem doesn’t exist is not a legal option. Instead, EPA needs to protect Iowans and follow the Clean Water Act by acknowledging that nitrate contaminates drinking water sources across the state.”

Last week, 83 groups called on EPA and the Department of Health & Human Services (HHS) to take emergency action on industrial agriculture’s nitrate water pollution crisis in Iowa and nationwide. A recent EWG report found that roughly 1 in 5 Americans’ drinking water contains nitrates, and substantial new evidence suggests that nitrate exposure may be toxic at far lower levels than the current federal safety threshold, meaning that people are being exposed to dangerous chemicals even from regulated water systems that meet current safety standards.