Iowa's Pollution Problems: What's The Main Culprit?

Iowa has one of the highest rates of nitrate pollution in the United States, with manure spills, factory farms, and agricultural pollution being the main contributors. The state's water quality is in crisis, with high levels of nitrate in the water leading to a range of health issues, including blue baby syndrome in children and colon cancer in adults. The state has also seen a rise in E. coli advisories, with Backbone State Park Beach recording a reading 85 times higher than Iowa's safety standard. With over 4,000 factory farms operating without permits and a lack of effective regulation, Iowa's pollution problem is causing significant harm to both the environment and public health.

Manure pollution

The impact of manure pollution extends beyond drinking water. It also affects Iowa's beaches, with E. coli advisories on the rise. E. coli can cause gastrointestinal illnesses, meningitis, and even death in vulnerable populations. Backbone State Park Beach, for example, has been heavily impacted, with E. coli levels reaching 85 times the state's safety standard. This contamination is due to the drainage of farmland into the small lake, showcasing the far-reaching consequences of manure pollution.

The manure spills are often caused by dairy manure land-applied runoff and the lack of proper discharge permits among concentrated animal feeding operations. A single "anthropogenic" spill in northwest Iowa killed between 100,001 and 500,000 fish, according to reports. Environmental advocacy groups have called for stricter regulations, such as the proposed "Clean Water for Iowa Act," which aims to enforce the Clean Water Act and require National Pollutant Discharge Elimination System permits for medium and large-scale feeding operations.

Iowa's current permit system relies on self-reporting by factory farms, which has been criticised as ineffective and prone to underreporting. Additionally, the fines imposed by the Iowa Department of Natural Resources on offenders are often insufficient to cover the costs of remediation and fail to incentivise meaningful change in business practices. As a result, the state's residents bear the burden of the pollution, both in terms of health consequences and financial costs.

To address the issue of manure pollution in Iowa, there is a growing call for stricter regulations and enforcement of existing laws to hold factory farms accountable for their waste management practices. Environmental watchdog groups, such as Food & Water Watch, play a crucial role in advocating for policy changes and raising awareness about the impact of manure pollution on Iowa's water sources and the health and well-being of its residents.

Nitrate pollution

One of the primary sources of nitrate pollution in Iowa is agricultural runoff. The state's extensive agricultural activities result in large amounts of fertilizer and manure being applied to fields, which can then be washed into nearby water bodies during rainfall or irrigation. This runoff contains high levels of nitrates, leading to increased nitrate concentrations in Iowa's streams and rivers. The state's heavy reliance on groundwater for drinking water further exacerbates the issue, as contaminated water can pose serious health risks to those who consume it.

The impact of nitrate pollution on Iowa's drinking water has been significant. Between 2003 and 2017, elevated nitrate levels (3 milligrams per liter or mg/L) were detected in the tap water supplies of 236 towns and cities in Iowa, affecting approximately 1.3 million people. The problem was more prevalent in smaller, rural communities, with 73% of communities experiencing increasing nitrate levels during this period. This trend is concerning as these communities often lack the resources and infrastructure to adequately treat contaminated water.

The health risks associated with nitrate pollution are severe. Recent studies have linked nitrate consumption to an increased risk of colorectal cancer, thyroid disease, and neural tube birth defects, even at levels below the federal drinking water standard of 10 mg/L. According to research by the Environmental Working Group, nitrate pollution in Iowa's drinking water may contribute to up to 300 cases of cancer annually. The group's analysis estimated that four-fifths of these cases were occurrences of colorectal cancer, with the remaining being ovarian, thyroid, kidney, and bladder cancer.

Addressing nitrate pollution in Iowa requires a multifaceted approach. While agricultural practices are a significant contributor, it is essential to work collaboratively with farmers to implement sustainable farming techniques that minimize nitrate runoff. This includes adopting edge-of-field conservation practices, such as buffer strips and cover crops, which can help capture and reduce nitrate levels in runoff. Additionally, improving water treatment processes and increasing access to water quality testing, especially for private wells, can help mitigate the health risks associated with nitrate contamination.

Factory farms

Iowa's factory farms are a major contributor to the state's pollution crisis. With more factory farms than any other state, Iowa's agricultural climate footprint is significant. Factory farms are responsible for driving the state's climate pollution, with agriculture contributing 38% of Iowa's greenhouse gas emissions. The state also has the highest emissions of the potent greenhouse gases methane and nitrous oxide, with factory farms producing, concentrating, and storing vast amounts of methane-rich manure.

The impact of factory farms on Iowa's water quality is also significant. In the past decade, Iowa's factory farms have illegally contaminated waterways with animal manure at least 179 times, in quantities of up to 1 million gallons. This has resulted in fish kills, with more than half occurring in a single 2014 spill that extended 28 miles and killed over 865,000 fish. The state's drinking water cleanup costs have soared to an estimated $66 million annually due to nitrate contamination from manure spreading and nitrogen fertilizers.

The state's water bodies are also suffering from E. coli contamination, with more than half of Iowa's rivers and streams designated as "impaired" in 2024. This has impacted the public's ability to enjoy natural spaces, with the DNR issuing 134 E. coli warnings across 39 public beaches in one year.

The expansion of factory farms in Iowa has led to the decline of small family-owned operations, with massive factory farms taking over. The waste produced by these corporate-run industrial animal agriculture operations directly impacts Iowans, with Iowa's factory farms producing 109 billion pounds of waste annually, 25 times the state's human population.

The state's policies, such as the 2021 law that expanded digester use to large-scale factory farms, have come under criticism for supporting biogas, which is made from manure and contributes to methane emissions. Unless bold policies are implemented to hold the industry accountable and prevent further harm, Iowa's pollution crisis will continue to worsen.

Lack of regulation

Iowa is a leader in agriculture and clean energy, and the state works to protect its land, air, and water. The Iowa Department of Natural Resources (DNR) is responsible for protecting Iowa's natural resources and enforcing environmental regulations.

However, there have been concerns about a lack of regulation in the state, particularly in the areas of water quality and mining. The Environmental Law Division of the Iowa Attorney General's Office plays a crucial role in enforcing environmental laws and providing legal assistance. For instance, the division enforces laws related to coal and mineral mining, water quality, and abandoned mine land reclamation projects. It also assists in collecting administrative penalties for violations, including those related to pesticide handling.

One example of the challenges posed by a lack of regulation is the issue of wetland protection. A lawsuit was filed seeking to weaken wetland protections, which could have detrimental effects on the environment. The ELPC (Environmental Law & Policy Center) has intervened in this lawsuit, seeking to protect wetlands and promote renewable energy.

Additionally, the division is responsible for advising and representing various agencies and boards, including the Iowa Comprehensive Petroleum Underground Storage Tank Fund Board and the State Archaeologist. They also advise the Iowa Commissioner to the Midwest Interstate Low-Level Radioactive Waste Commission, highlighting the diverse range of environmental concerns in the state.

In conclusion, while Iowa has made efforts to protect its environment, there are concerns about a lack of regulation in certain areas. The Environmental Law Division plays a crucial role in enforcing laws and providing legal assistance, but ongoing challenges, such as those related to water quality and mining, require continued attention and stronger regulatory measures to ensure the protection of Iowa's natural resources.

Cancer rates

Iowa has the second-highest and fastest-rising cancer incidence in the US, according to a 2024 report by the Iowa Cancer Registry. The report, however, did not mention agricultural pollution as a contributing factor. Instead, it focused on the carcinogenic effects of alcohol and high rates of binge drinking in the state. This has been disputed by critics, including health professionals, who point to the extensive use of pesticides and fertilizers in farming.

The state's agricultural practices, including heavy pesticide use and large-scale livestock farming, are under scrutiny for their potential role in cancer rates. Iowa farmers spread nearly 54 million pounds of pesticides, 2 billion pounds of commercial fertilizer, and 50 million tons of animal manure annually—more than in any other state. These farm pollutants heavily contaminate surface and groundwater across Iowa, potentially exposing even those who don't live or work on farms. Links between farm contaminants and disease have been studied for decades, with researchers finding increased risks of bladder and ovarian cancers associated with elevated nitrate levels in public drinking water.

The Agricultural Health Study, a 30-year study of 89,000 pesticide applicators and their spouses in Iowa and North Carolina, found that farmers have a higher rate of prostate cancer. The study also showed that applicators who used the weedkiller dicamba had an elevated risk of liver cancer and intrahepatic bile duct cancer. Another study found that greater use of the herbicide atrazine increased the risk of lung and prostate cancer.

Nitrates, a contaminant from agricultural sources, have been identified as a potential cause of cancer. Nitrate is found at potentially harmful levels in one-in-twenty Iowa public drinking water systems and in more than 12,000 private wells in the state. While there are challenges in determining the exact causes of cancer, experts are calling for further research into the agricultural industry's role in Iowa's high cancer rates.

In addition to pesticides and nitrates, manure pollution from factory farms is also a concern in Iowa. The state is the nation's top hog producer, with around 53.4 million hogs, and these large confinements are known to pollute air and groundwater. Some manure is sprayed on crops as fertilizer, while some are illegally discharged into public waterways. This has led to calls for stricter regulation and enforcement of the Clean Water Act, with advocates pushing for a "Clean Water for Iowa Act".

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