The Us's Most Polluted River: A Troubling Story

The health of US rivers is critical to the health and safety of communities and wildlife. River pollution in the USA is an ongoing issue, with millions of miles of rivers being treated as open sewers and garbage cans for over a century. While the Clean Water Act has helped improve river cleanliness, climate change, agricultural runoff, and industrial pollution continue to pose threats. The Ohio River, a lifeline for six states, is currently the most polluted river in the US, with industrial pollution and contamination affecting the health of those who depend on it.

The Ohio River: industrial pollution

The Ohio River has faced a myriad of issues due to industrial pollution. In 2020, industrial facilities released approximately 193.6 million pounds of toxic pollution into US waterways, with the Ohio River watershed accounting for over one-fifth of the total pollution. This included toxic chemicals such as nitrates, which can cause developmental and birth defects in humans, as well as lower dissolved oxygen levels, leading to toxic algal blooms. In 2019, these algal blooms were observed along 265 miles of the Ohio River.

The Ohio River's pollution is largely attributed to industrial discharges from coal-fired power plants, steel and aluminium manufacturers, and petrochemical plants. For instance, the steel producer North American Stainless in Carroll County dumped over 3 million pounds of toxic waste in 2020, making it the largest polluter in Kentucky by volume. Additionally, Louisville Gas and Electric's Mill Creek coal-fired power plant in Kentucky released the highest toxicity-weighted pounds of discharges, including heavy metals such as arsenic, nickel, and chromium.

The Ohio River is an essential resource for the region, providing drinking water for 5 million people and supporting recreation and economic activities. However, the river has experienced some of the worst flooding in the past decade, and climate change may render historical data less relevant for future decision-making. To address these challenges, there have been discussions about maximizing the river's potential for industry, agriculture, energy, recreation, and drinking water.

The Ohio River is not the only waterway facing threats. California and Mexico's Tijuana River, Connecticut's Farmington River, and California's Trinity River are all facing pollution issues that impact the health and well-being of the local communities and wildlife.

The Neuse River: poor wastewater treatment

The Neuse River, named after the indigenous Neusiok people, meaning "peace river", was once one of the most polluted rivers in the US. The Clean Water Act of 1972 has been instrumental in driving improvements, with communities along the river answering the Act's ambitious call to make the river safe and clean for everyone.

The Neuse River Resource Recovery Facility in Raleigh has played a pivotal role in the river's rehabilitation. The facility treats 44 million gallons of water daily, serving 500,000 people. The plant has undergone significant upgrades, including the implementation of total nitrogen removal facilities and sludge management strategies. The transition from chlorine contact tanks to ultraviolet disinfection has been crucial in improving water quality.

The City of Raleigh has also focused on sustainability initiatives, aiming to mine resources from wastewater and convert sludge into fertilizer for sunflower fields. These efforts have resulted in a 20% reduction in annual energy costs, with plans to use recovered gas to fuel the city's transit bus fleet.

The Neuse River's recovery is a testament to the diligent work of the communities and partners involved. The river's improved health has positively impacted both the environment and the economy, showcasing the significance of investing in sustainable practices for the benefit of rivers and streams nationwide.

While the Neuse River has made remarkable progress, ongoing vigilance is necessary to address new challenges, such as the growing effects of climate change, to ensure the river's health and the equitable distribution of its benefits among the communities it supports.

Tijuana River: choked with pollution

California and Mexico's Tijuana River is one of the most polluted rivers in the US. It has been at the centre of a transboundary pollution crisis on the US-Mexico border for decades, resulting in public health issues, beach closures, and massive environmental degradation of the Tijuana River Estuary and coastal marine waters from Tijuana to Coronado.

The discharge of untreated sewage containing high levels of faecal bacteria into the river has resulted in frequent beach closures, endangering marine life and habitats and posing direct health risks to communities. The Tijuana River Estuary, recognised as a "Wetland of Global Importance" by the UN's Ramsar Convention, has been severely degraded by decades of sewage, chemicals, trash, and sediment being dumped into it from both sides of the border. The Estuary and offshore habitats are home to hundreds of terrestrial and marine species, and the pollution has had a detrimental impact on the region's biodiversity.

The Tijuana sewage pollution crisis is attributed to a combination of outdated infrastructure, extreme weather conditions, and a lack of adequate maintenance and upgrades. Since October 2023, 31 billion gallons of raw sewage, polluted stormwater, and trash have flowed into the Tijuana River, causing significant environmental damage and impacting the local economy, particularly in the tourism sector.

Efforts have been made to address the crisis, with Governor Newsom helping to secure $703 million in federal funding for critical upgrades to the South Bay International Wastewater Treatment Plant. Additionally, California has allocated $35 million in state funding to support cleanup efforts and protect public health in the region.

The Tijuana River pollution crisis highlights the urgent need for comprehensive and sustainable solutions to address water pollution and protect the environment and public health.

Mississippi River: agricultural runoff

The Mississippi River is one of the most polluted rivers in the United States, with agricultural runoff being a major contributor. This runoff is caused by excess fertilizer and animal waste, which are carried into the river system by rainfall or melting snow. This leads to a process called eutrophication, where aquatic plant life, such as algae, grows and dies at high rates, using up the nutrients in the water and blocking sunlight from penetrating the surface. This inhibits photosynthesis and leads to the depletion of dissolved oxygen, resulting in the death of marine life.

Nitrogen and phosphorus are the most common agricultural pollutants found in the Mississippi River Basin. These chemicals contribute to harmful algae growth, fish kills, and the classification of some drinking water sources as unsafe. The Dead Zone in the Gulf of Mexico, an area devoid of life, is fueled by nutrient runoff from the Mississippi River. Farms in Illinois, Iowa, Ohio, and southwest Minnesota contribute significantly to this through the use of drainage tiles, which flush nitrogen fertilizer into tributaries that eventually lead to the Gulf.

Fertilizer runoff from farms is a significant issue, as farmers tend to over-fertilize their crops to increase yield and prevent under-fertilization. Even when fertilizer is applied at appropriate times and rates, some of it still ends up in the water. Animal waste from livestock operations, specifically Concentrated Animal Feeding Operations (CAFOs), is another major contributor to agricultural runoff. Improper storage or application of animal waste as fertilizer can result in runoff that washes into waterways.

To address these issues, the Environmental Protection Agency (EPA) has asked states along the Mississippi River to develop Nutrient Reduction Strategies. These strategies aim to reduce nitrogen and phosphorus loading in surface waters and should include new initiatives and funding streams. The MRC Agriculture Group, for example, focuses on reducing nitrogen and phosphorus pollution in the Basin's rivers, lakes, and streams. They recommend limiting pollution in stormwater runoff from farm fields, improving enforcement of CAFO regulations, and targeting public funding for conservation activities to priority watersheds.

Agricultural runoff is a significant challenge for the Mississippi River, and it requires a combination of regulatory measures, farmer incentives, and conservation efforts to mitigate its impact on the river ecosystem and the Gulf of Mexico.

Willamette River: industrial and agricultural pollution

The Willamette River, a major tributary to the Columbia River, is the 13th largest river in the US in terms of flow. Over the years, the river has been subjected to various forms of industrial and agricultural pollution, threatening the health of the river ecosystem and the species that depend on it.

One of the significant sources of industrial pollution in the Willamette River is the discharge of raw sewage, known as combined sewer overflows (CSOs), by the City of Portland. This issue was addressed through a lawsuit filed by the Northwest Environmental Advocates (NWEA) against Portland, which resulted in a significant reduction in raw sewage discharges. However, the Oregon Department of Environmental Quality (DEQ) was initially complicit, only intervening to assist Portland in defending itself in court. The lawsuit established a legal precedent, empowering citizens to enforce narrative conditions in water pollution discharge permits.

Agricultural activities have also contributed to the pollution of the Willamette River. Upstream farmers engaged in practices that negatively impacted water quality, including the use of pesticides and logging. The loss of floodplain, riparian habitat, and river complexity due to agricultural and urban development has further exacerbated the problem. These changes have resulted in a "Threatened" listing for Spring Chinook salmon under the Federal Endangered Species Act due to poor fish passage at dams on the tributaries.

In addition to sewage and agricultural runoff, the Willamette River has also faced pollution from toxic waste dumping and industrial activities. A Superfund site in Portland Harbor spans 10 miles of contaminated sediments laden with hazardous chemicals such as PCBs, DDT, and oil-based pollutants. The river has also been affected by point-source pollution, non-point source pollution, and runoff from urban and rural areas.

Efforts to improve water quality in the Willamette River basin have been ongoing. In 2008, the Oregon DEQ developed clean-up plans to address mercury pollution, a toxic contaminant found at concerning levels in the river. However, the Willamette Mercury TMDL (Total Maximum Daily Load) was criticized for its shortcomings, including the absence of limits on mercury pollution sources, despite being approved by the Environmental Protection Agency (EPA). NWEA has actively worked to enhance Oregon's water quality standards, particularly regarding temperature control, which is crucial for the survival of cold-water fish species such as salmon, steelhead, and bull trout.

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