Iowa's Water Pollution Crisis: Understanding The Severity

Iowa's water pollution is a pressing issue, with the state's waterways heavily contaminated by agricultural runoff, industrial waste, and other sources. The Iowa Department of Natural Resources (DNR) plays a crucial role in monitoring and addressing water quality, but the scale of the problem remains vast. In 2022, the DNR identified 751 impaired water bodies, including rivers, lakes, streams, reservoirs, and wetlands, with pollution levels impacting recreation, aquatic life, and drinking water sources. This accounts for 54% of the 1382 segments assessed, indicating a significant challenge for the state. The sources and impacts of Iowa's water pollution are diverse and complex, and addressing them will require concerted efforts from policymakers, industries, and communities alike.

The Clean Water Act

Iowa's waterways are highly polluted, with 751 impaired waters in 2022, 599 of which were rivers and streams. The Clean Water Act (CWA), enacted in 1948 as the Federal Water Pollution Control Act, provides a framework for regulating pollutant discharges into US waters and maintaining water quality standards. The CWA mandates that the Environmental Protection Agency (EPA) implements pollution control programs and sets wastewater standards for industries.

The 1972 amendments to the CWA gave it its common name and strengthened its provisions. These changes made it unlawful to discharge pollutants from a point source into navigable waters without a permit. The EPA's National Pollutant Discharge Elimination System (NPDES) permit program controls these discharges. The CWA also maintains requirements to set water quality standards for all contaminants in surface waters.

The CWA requires states to submit a list of impaired waters, known as the 303(d) list, to the EPA every two years. This list identifies water bodies impaired by point source and non-point source pollutants, with the latter primarily stemming from agricultural activities. Once a water body is placed on the 303(d) list, a TMDL (Total Maximum Daily Load) plan is developed to improve water quality. The TMDL determines the maximum amount of pollutant(s) a water body can receive to meet its designated use, and local communities are involved in its implementation.

Impaired waterways

Iowa's waterways are highly polluted, with 751 impaired waters identified in the 2022 list submitted by the Iowa Department of Natural Resources (DNR) to the Environmental Protection Agency (EPA). This list, known as the 303(d) list, is required by the Clean Water Act and includes lakes, rivers, streams, wetlands, and reservoirs that are impaired by point source and non-point source pollutants.

Rivers and streams are the most polluted, with 599 impaired segments, followed by lakes, with 102 impaired waters. These impairments are caused by various pollutants, including E. coli, bacteria, turbidity (water clarity), chemicals, high levels of nitrates and phosphorus, pH issues, fish kills, and algae. For example, Lake Wapello in Davis County has been listed due to high mercury levels in fish, while Lake Rathbun has issues with turbidity, which can lead to increased algae growth.

The DNR's reporting format previously allowed for easy searching of specific counties to identify impaired waterways. However, the current format makes it more challenging to determine which local waterways may be impaired. The DNR is required to maintain a separate list of waters requiring further investigative monitoring, which includes waterbody segments with limited information suggesting potential water quality impairment.

To address water pollution, Iowa has implemented TMDLs (total maximum daily loads), which determine the maximum amount of pollutant(s) allowed to ensure the waterbody meets its designated use. Once a TMDL is developed and approved by the EPA, the water body is removed from the 303(d) list, even if pollution levels remain high. The DNR reports that non-point sources, primarily agriculture, contribute significantly to phosphorus and nitrate pollution in Iowa's waterways.

Drinking water quality

Iowa's drinking water quality is a growing concern, with the state's waterways heavily polluted by agricultural and industrial sources. The Iowa Department of Natural Resources (IDNR) is responsible for ensuring the safety of public drinking water sources, which include city water utilities, rural water supplies, and mobile home parks, serving more than 25 individuals daily. In 2021, the IDNR recorded 1,842 public water supply systems, and 96.2% of these systems were in compliance with all health-based standards.

However, the IDNR's 2022 impaired waters list, known as the 303(d) list, revealed that Iowa's waterways remain in a dire state. Of the 1,382 segments assessed, 54% were impaired, with rivers and streams being the most polluted. The primary sources of pollution are agricultural runoff, including fertilizer and livestock waste, and industrial waste from factory farms. This pollution has led to high levels of E. coli, bacteria, chemicals, nitrates, and phosphorus in the water, which can have serious health consequences for humans.

Private wells, which serve approximately 7% of Iowans, are also a source of drinking water. It is the responsibility of private well owners to maintain water quality and conduct annual testing for pollutants. However, many wells are contaminated with bacteria, arsenic, and nitrates, which can pose health risks to those consuming the water.

The Clean Water Act, which requires the submission of the 303(d) list to the Environmental Protection Agency (EPA) every two years, aims to address water pollution. Additionally, plans like TMDL aim to improve water quality by determining the maximum allowable pollutant levels. Despite these efforts, Iowa's water pollution remains a significant issue, impacting the health and well-being of its residents and the environment.

Overall, while efforts are being made to ensure safe drinking water in Iowa, the state continues to struggle with water pollution, particularly from agricultural and industrial sources. As a result, the quality of drinking water varies across the state, with some areas experiencing higher levels of contamination and non-compliance with health standards.

Agricultural pollution

Iowa's waterways are heavily polluted, with 751 impaired waters identified in 2022—a figure that has barely improved since 2020. Of the 1382 segments assessed, 54% were impaired. Rivers, including streams, are the most polluted, with 56% of those tested impaired. Iowa's lakes are also heavily polluted, with 65% of those tested landing on the impaired list.

The state's transition from small farms to sprawling industrial agricultural operations has exacerbated the problem. Iowa's factory farm industry raises 23.5 million hogs annually, yet the number of hog farms has decreased by 90% since 1982. This shift has resulted in a concentration of animal waste and chemical use, with manure spills and chemical runoff polluting waterways. The DNR's impaired waters list includes lakes, rivers, streams, reservoirs, and wetlands, with pollutants such as E.coli, bacteria, turbidity, chemicals, high levels of nitrates, phosphorus, pH issues, fish kills, and algae.

While some farmers have implemented conservation practices to reduce nutrient runoff, there is a lack of incentive for many to adopt more sustainable methods. The Iowa Farm Bureau has requested more time and incentives for farmers to transition to new strategies. However, without increased government regulation or effective voluntary measures, the problem of agricultural pollution in Iowa's waterways is likely to persist.

Health risks

Iowa's waterways are heavily polluted, with 751 of them impaired as of the 2022 impaired waters list. This includes rivers, streams, lakes, reservoirs, and wetlands. The sources of pollutants vary, from E. coli and bacteria to chemicals, high levels of nitrates, and phosphorus.

The health risks associated with polluted water are significant and wide-ranging. Firstly, microbial contamination of drinking water, caused by faeces, is a major risk factor. This can lead to various gastrointestinal illnesses, including diarrhoea, cholera, dysentery, typhoid, and polio. Diarrhoeal diseases are a particular concern, causing an estimated 505,000 deaths each year, with children under five being especially vulnerable.

Contaminated water can also cause acute respiratory infections and neglected tropical diseases. Viruses, bacteria, and parasites can result in stomach pain, vomiting, diarrhoea, headache, fever, and even kidney failure. Infectious diseases, such as hepatitis, can be severe or even fatal for those with weakened immune systems, including infants and the elderly.

Chemical exposure through polluted water is another serious health risk. This can lead to skin discolouration, nervous system damage, organ damage, and reproductive issues. Long-term exposure to certain chemicals in drinking water can also increase the risk of developing chronic diseases, including cancer.

Furthermore, water pollution can lead to the growth of toxic algae, such as microcystin, which can sicken people and even kill dogs. High levels of phosphorus, often caused by agricultural runoff, contribute to this issue by choking oxygen out of the water and killing aquatic life.

The impact of water pollution on human health is significant, with 80% of diseases and 50% of child deaths worldwide linked to poor water quality. Improving water supply and sanitation is crucial to reducing the incidence of waterborne diseases, especially in developing countries.

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