Water Pollution In Iowa: Is It A Concern?

Water pollution in Iowa is a pressing issue, with the state's waterways facing significant challenges. The state's agricultural practices, engineering projects, and natural conditions have contributed to degraded water quality, particularly in Western Iowa. High levels of nitrogen, phosphorus, and other pollutants have led to toxic algae blooms, contaminated drinking water sources, and adverse health impacts on both people and animals. With pollution from fertilizer runoff, livestock feces, and pesticides, Iowa's water bodies are under threat, and despite efforts and investments to improve the situation, the problem persists and, in some cases, is worsening.

High levels of bacteria, arsenic, and nitrate in private wells

Iowa's private wells have been found to be contaminated with unsafe levels of nitrate, coliform bacteria, and fecal coliform bacteria. An investigation by the Environmental Working Group and the Iowa Environmental Council revealed that between 2002 and 2017, thousands of wells across the state, particularly in rural areas, were affected by these contaminants. The primary source of this contamination has been attributed to agricultural practices, especially in rural regions, where farms contribute nitrate from fertilizer and animal manure, as well as bacteria from manure applied to fields. These contaminants then seep through the soil or run off unprotected fields, ultimately polluting drinking water sources.

The presence of these contaminants in private wells has serious implications for public health. The U.S. Environmental Protection Agency has declared that there is no safe level of coliform or fecal coliform bacteria in drinking water. While most coliform bacteria do not pose direct harm, certain strains of E. coli can induce diarrhea, vomiting, and even lead to fatal consequences. Moreover, the existence of coliform bacteria in drinking water suggests the potential presence of other harmful pathogens.

Nitrate contamination in private wells is equally concerning. High nitrate levels in drinking water can elevate cancer risk and cause birth defects. This issue is particularly acute in Iowa, where an estimated 230,000 to 290,000 residents rely on private wells for their water supply. The Iowa DNR and public health agencies recommend annual testing of private water supplies and immediate testing if any changes in water quality are observed, such as alterations in colour, clarity, taste, smell, or sediment.

Arsenic contamination is another concern in Iowa's groundwater. Prior studies indicate the presence of arsenic in groundwater across many areas of the state. The Iowa DNR recommends that all private well users test their well water for arsenic at least once. If elevated arsenic levels are detected, more frequent testing may be necessary to monitor the situation and make informed decisions about installing water treatment systems or discontinuing the use of the water.

Nitrogen pollution in waterways

Iowa's waterways are facing a significant challenge due to nitrogen pollution, which is having a detrimental impact on the state's aquatic ecosystems and drinking water sources. Nitrogen, in the form of nitrates, is one of the primary pollutants affecting Iowa's rivers and streams. The source of this pollution is largely attributed to agricultural activities, with an estimated 92% of nitrate pollution stemming from non-point sources, primarily factory farms and fertilized fields.

Factory farms in Iowa produce a substantial amount of manure, which can find its way into nearby waterways through over-application, runoff, and spills. In addition, monocropped corn and soy production rely heavily on commercial fertilizers, which can leach nitrogen into the water through tile lines, an underground drainage system. This excess nitrogen acts as a fertilizer in the water, leading to excessive growth of algae, including toxic forms such as microcystin.

The consequences of nitrogen pollution are far-reaching. The overgrowth of algae chokes the oxygen out of the water, creating hypoxic areas known as "dead zones." These dead zones can cover vast areas, such as the 6334 square-mile dead zone in the Gulf of Mexico, which was a result of nitrogen runoff from Iowa's waterways flowing into the Mississippi River and eventually into the Gulf. The hypoxic conditions kill fish and other marine life, impacting the ecosystem and the livelihoods of coastal communities.

Additionally, nitrogen pollution in drinking water sources poses a serious health risk to Iowans. High nitrate levels in water can cause short-term health effects, such as nausea and headaches, and can be especially harmful to vulnerable populations. From 2010 to 2015, more than 60 Iowa cities and towns were found to have contaminated drinking water with high nitrate levels. The Iowa Environmental Council has estimated that, at the current rate of remediation, it could take hundreds to thousands of years to significantly reduce nitrogen pollution levels.

Addressing nitrogen pollution in Iowa's waterways is crucial to protecting both the environment and public health. While efforts like the Nutrient Reduction Strategy (NRS) aim to reduce nitrogen pollution, more stringent measures and better-funded remediation programs are needed to effectively tackle this issue.

Pollution from agriculture

Iowa's water pollution is a growing concern, with agricultural practices contributing significantly to the issue. The state's agricultural industry, particularly factory farming and corn and soybean production, has been identified as a major source of water pollution.

One of the primary concerns regarding agricultural pollution in Iowa is nitrate contamination. Nitrates from fertilizer runoff and manure from factory farms have been detected in the state's rivers, including the Des Moines and Raccoon Rivers. This contamination poses a significant threat to human health, as nitrates have been linked to various health problems, including thyroid disease, "blue baby syndrome," and certain types of cancer. The presence of nitrates in drinking water can lead to increased costs for water utilities and higher water bills for residents, as seen in the case of Joe Henry, a resident of Iowa, whose water bill doubled over a decade, partly due to agricultural pollution.

In addition to nitrate pollution, agricultural practices in Iowa have also been associated with other forms of water contamination. For example, perforated pipes used in corn and soybean fields to drain excess rainwater and snowmelt have been identified as "point sources" of pollution, potentially requiring regulation under the federal Clean Water Act. The lawsuit filed by Stowe against drainage districts upstream of Des Moines brought attention to this issue, highlighting the need for stronger measures to address agricultural pollution.

The impact of agricultural pollution extends beyond the immediate contamination of water sources. It also affects the local ecosystem and communities that rely on clean water. For instance, the Meskwaki Nation, who value caring for the land and water as essential to their way of life, face threats to their waterways from upstream industrial agriculture. Returning some of the land currently used for corn and soybean production to pasture and prairie could help mitigate these issues.

While there have been some efforts to address agricultural pollution in Iowa, such as the implementation of a $5 per acre rebate on crop insurance for farmers adopting cover crops, the overall regulatory climate suggests little prospect of increased government intervention. The Iowa Farm Bureau has acknowledged the problem but has requested more time and incentives for farmers to adopt more sustainable practices. In the absence of stronger regulations and enforcement, the burden of dealing with the consequences of agricultural pollution falls on the residents of Iowa, including vulnerable communities disproportionately affected by water contamination.

Ineffective state and federal regulations

Iowa's water quality is a pressing issue, with concerns about both public water supplies and private wells. While public water supplies are regulated to uphold specific water quality standards, issues with private wells, which serve fewer than 25 individuals per day, have come to light. The responsibility for maintaining the water quality of private wells falls on the well owners, who are expected to conduct annual testing for pollutants. However, ineffective state and federal regulations have led to challenges in ensuring safe drinking water for all.

The Iowa Department of Public Health has reported that pollutants like bacteria, arsenic, and nitrate are found at elevated levels in 10-30% of private wells. This is a significant concern as private wells are the primary drinking water source for many Iowans. The presence of bacteria, such as E. coli, indicates faecal pollution and the potential presence of pathogens, posing a serious health risk to those consuming the water.

The Grants-to-Counties Program, which offers free or low-cost annual testing for private wells, is a step in the right direction. However, it does not address the underlying issue of inadequate regulations and enforcement. Well construction, geographic setting, and land use in the watershed all play a role in water quality, and older wells may have fewer protective features in place. Without clear and stringent regulations, backed by robust enforcement mechanisms, private well owners are left vulnerable to contaminated water sources.

Furthermore, the lack of standardised documentation and consistent construction standards for private wells exacerbates the challenge of maintaining water quality. Many well owners may not have access to information about the construction of their wells, making it difficult to identify potential risks and vulnerabilities. This gap in knowledge could lead to unforeseen issues and challenges in maintaining safe drinking water standards.

In conclusion, while Iowa has made some efforts to address water quality issues, ineffective state and federal regulations have hindered progress. It is essential that regulations are strengthened and enforced to protect the health and well-being of those relying on private wells as their primary water source. Clear guidelines, regular inspections, and robust enforcement mechanisms are needed to ensure that all Iowans have access to safe and clean drinking water.

Fecal coliform/E. coli in drinking water

Iowa's drinking water comes from two main sources: public water supplies and private wells. Public water supplies include city water utilities, rural water supplies, mobile home parks, and other systems that regularly serve 25 or more individuals. These systems are regulated to maintain specific water quality standards. Private wells, on the other hand, generally serve fewer than 25 individuals per day and it is the responsibility of private well owners to maintain water quality, including annual testing for pollutants like bacteria, arsenic, and nitrate.

Fecal coliform, a type of total coliform, is derived from the guts and feces of warm-blooded animals, including humans. E. coli, a type of fecal coliform, indicates fecal pollution and the possible presence of pathogens. The presence of fecal coliform/E. coli in drinking water suggests a pathway from a relatively fresh waste/sewage source, which is a serious health concern due to the potential contamination of enteric microorganisms that can cause disease. While total coliforms are generally harmless, E. coli can cause short-term health effects like nausea and headaches, and some rare strains like E. coli 0157:H7 can lead to more serious illnesses.

The Grants-to-Counties Program in Iowa usually tests for total or fecal coliforms, and if a problem is detected, they may recommend further testing for E. coli. Private well owners should test for bacteria annually, and if any bacteria are detected, the well is considered unsafe. Late spring or early summer is the best time to test for contamination as it is more likely to show up during wet weather.

When fecal coliform or E. coli are detected in public water systems, water providers investigate the source of contamination, collect additional water samples for testing, and may inspect the entire system. If the presence of coliform bacteria is confirmed, the water system should be inspected to identify and eliminate any possible sources of contamination. Public health authorities will also issue advisories, recommending the use of boiled or bottled water, and informing customers of the actions being taken to correct the issue.

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