As the Des Moines metro begins watering lawns again, tests show some rivers and faucets still carry nitrate concentrations above federal safety limits, linking farm runoff to Iowa’s stubbornly high cancer rates.
Nina B. Elkadi reports for Sentient.
In short:
- Most of Iowa’s runoff comes from nitrogen-rich fertilizer and manure applied to row crops; when heavy rains flush the excess into rivers, utilities pay up to $16,000 a day to strip nitrates from drinking water.
- Gov. Kim Reynolds says new rules are unnecessary, but Polk County’s own review finds that most of the state’s surface water pollution comes from unregulated farm sources and that voluntary measures are falling short.
- Citizen scientists feeding data to Nitrate Watch have logged tap samples in Des Moines as high as 20 mg/L — double the U.S. Environmental Protection Agency’s limit of 10 mg/L.
Key quote:
“Over the last 15 years, I’ve been cautious about getting into our ponds and rivers and lakes here in Iowa."
— Rich Gradoville, retired teacher and bladder cancer survivor
Why this matters:
Epidemiological studies tie long-term nitrate exposure to bladder, ovarian, and colorectal cancers, while infants can suffer life-threatening “blue baby” syndrome when concentrations top 10 mg/L. Iowa’s hogs and cattle generate billions of pounds of manure each year, and ever-heavier Midwest downpours driven by climate change wash that nitrogen into the Des Moines and Raccoon Rivers, shifting treatment costs onto ratepayers. As utilities expand multimillion-dollar removal plants, residents face a double burden: higher water bills today and increased medical risks tomorrow. The state’s experience underscores how agricultural policy, drinking-water safeguards and public-health outcomes are tightly linked.
Related: Iowa rivers face record nitrate levels following heavy rains
