DES MOINES, Iowa — Iowa water quality and climbing cancer rates have moved to the forefront of state politics, overtaking long-simmering concerns as candidates across the ballot confront a complex mix of public health, agriculture and infrastructure policy.
The state is also grappling with a budget gap, higher costs and trade pressures that have squeezed farmers. Yet what had often been a politically delicate topic, given the strength of Iowa’s agricultural industry, now anchors debate questions, roundtables and campaign ads for both parties.
Runoff from chemical fertilizers and animal waste, which contain nitrates and phosphorus, can be swept by rain and snowmelt into a network of rivers and lakes that supply drinking water. The issue has long fueled tension between urban communities that depend on surface water and largely conservative rural areas stewarding productive farmland. While more farmers are adopting practices to limit runoff, critics argue that voluntary efforts leave downstream residents paying for pollution.
Public scrutiny intensified after consecutive years of water-use limits in the Des Moines area, alongside a growing “Make America Healthy Again” push that has resonated in small towns and rural communities. Iowa now has the nation’s second-highest rate of newly diagnosed cancers, and diagnoses such as prostate, breast and lung cancer are rising faster than the U.S. average in both urban and rural regions.
New state-funded research at the University of Iowa indicates most, but not all, of the state’s elevated rates for five cancers can be tied to demographic and behavioral factors, including smoking and binge drinking. Researchers will next examine environmental contributors, including nitrate exposure.
Democratic U.S. Senate candidate Josh Turek has pressed the connection, telling cancer patients that nitrates in water are a core concern and that residents deserve confidence their tap water is not making them sick.
Scientists have found associations between nitrates in drinking water and certain diseases, though the links remain disputed. The U.S. Environmental Protection Agency does not classify nitrates as a cancer risk. A federal review launched in 2017 has repeatedly stalled and restarted under different administrations.
Republican Rep. Ashley Hinson, Turek’s opponent, recently convened farmers, researchers and local officials to discuss Iowa’s water problems. She called for sustained investments in infrastructure, monitoring and conservation, while emphasizing that tap water meets federal standards and is safe to drink.
More than a decade ago, the Des Moines-area water utility, frustrated by spending about $16,000 a day to strip nitrates from drinking water, sued upstream counties to share costs. The case was dismissed, a decision celebrated by state Republican leaders. Last year, Central Iowa Water Works imposed its first-ever ban on lawn watering to reduce strain on nitrate-removal systems. At the time, state officials rejected blame-shifting toward farmers, noting Iowa’s ongoing investment of nearly $100 million annually in a nutrient reduction strategy.
Iowa water quality funding grows as debate intensifies
In May, Gov. Kim Reynolds and lawmakers approved an additional $320 million for water infrastructure, conservation incentives and other initiatives, including upgrades at Central Iowa Water Works. Reynolds said water quality is non-negotiable, characterizing it as a shared priority that transcends farm, city and party lines. Even so, critics, including candidates seeking to succeed her, say progress remains too slow.
Republican Zach Lahn and Democrat Rob Sand both argue the state must elevate the issue. Neither has called for mandatory farm conservation requirements to curb runoff. Lahn, who was endorsed early in his primary by MAHA Action, has gone further than many Republicans in directly linking polluted water and agrochemicals with Iowa’s cancer problem. At an agriculture-focused town hall in northeast Iowa in August, he acknowledged producers rely on key chemicals but said water quality must still be addressed.
Federal rules set a maximum contaminant level for nitrates in drinking water at 10 milligrams per liter, a standard intended to prevent infant methemoglobinemia, or blue baby syndrome. Researchers are now examining potential risks from nitrate exposure below that threshold and possible ties to certain cancers. Lahn said tests of his well and a nearby creek in rural east-central Iowa showed nitrate levels above the federal limit. Earlier this year, Central Iowa Water Works ran its nitrate-removal system for a record 193 consecutive days, with treated water often measuring eight to nine milligrams per liter during the summer peak.
Sand frequently references water in his stump speech, saying clean water advocacy helped draw him to the Democratic Party. After meeting with cancer survivors and parents of children with cancer this week, he said public concern has surged and some residents are questioning whether they want to remain in Iowa.
Research scientist Chris Jones recalled that two decades ago, when he worked for the Des Moines water utility, leadership wondered why there was not more outrage over nitrate levels. He says that outrage has now arrived, and he calls it a failure of the state if Iowans lose faith in their drinking water.
Jones, a Democrat running for secretary of agriculture against incumbent Republican Mike Naig, differs sharply with Naig on whether conservation measures should be mandated. In a debate, Naig said Jones is an outlier for seeking requirements on farmers. Many in the industry resist mandates, noting that not all operators own the land they farm and that some practices can initially cut into profits. Naig, a former Monsanto employee, touted record conservation activity under Reynolds and said efforts are scaling up to speed progress.
“It’s been a hot topic on the campaign trail,” Naig said, adding that Iowa needs a long-term view and is making headway.
