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The 7 Dirtiest Rivers in the USA

According to Save The Water, “In the United States alone, almost half of our rivers and streams are not safe enough for swimming, fishing, or drinking.” This is a bleak fact for those outdoor enthusiasts who enjoy connecting with nature.

But it’s also a testament to the impact of human development.

Let’s learn more about the seven dirtiest rivers in the USA and ways we can work to reduce pollution to create a better environment for everyone.

How Are Rivers Polluted?

There are numerous reasons rivers are polluted, but most are the results of human activity. Harmful chemicals from farming like pesticides and fertilizers drain into the area’s tributaries, creeks, and rivers. Oil spills or wastewater seeping into the ground also cause water pollution. Industrial factories emit chemicals such as phosphorus and nitrate into local water.

Humans drop trash into rivers.

And it’s not just local pollution. Factories and farms miles away also contribute. But the pollutants find their way into the rivers through rain and weathering. Plus, rivers feed into other bodies, spreading dirty water throughout the United States.

How Does River Pollution Affect Humans?

As the earlier statistic dictates, humans have discovered it’s harder and harder to find swimming holes. Although this may seem insignificant, it’s one way people connect with nature and enjoy the outdoors.

Fish and other animals die because of the polluted rivers, which leads to food chain disruptions. This can cause changes to our overall diet and affect the economy. For example, some areas may rely on the salmon population for food, but local fishermen also drive the local economy. Without a strong supply, the entire town suffers.

Finally, humans get their drinking water from rivers. With increasing pollution, the drinking water supply is limited. It can also become expensive to treat the water and remove all pollutants to become drinking-safe.

Kids standing next to one of the dirtiest rivers in the USA
More and more rivers are becoming polluted due to bad human habits.

The 7 Dirtiest Rivers in the USA

From the north to the south and east to west, rivers across America are getting dirtier and dirtier. Here are seven of the worst, all in the eastern part of the United States.

If you want a way to cool off on a hot summer day or looking to move to a city near these rivers, you may want to think again.

Ohio River

At almost 1,000 miles long, the Ohio River runs from western Pennsylvania into Illinois, where it meets the Mississippi River. Although it only runs through six states, it collects water from fifteen. During the Industrial Revolution, steel factories popped up all along the Ohio River. It made a good trade route. Cities sprung up around these factories. However, the results have been detrimental to the environment, with nitrate compounds and mercury polluting the Ohio River for over 100 years.

The algae bloom also results from the Ohio River’s pollution due to the power plants’ nitrates and phosphates.

In addition, the Ohio River flows through old mines, thus becoming contaminated with metals and sulfur. Raw sewage also discharges directly into the river. Swimming is prohibited in many stretches of the Ohio River.

Mississippi River

The second-largest river in North America, the Mississippi River, flows from Lake Itasca in Minnesota south for 2,340 miles. It then reaches the Gulf of Mexico in Louisiana. It drains 32 states and two Canadian provinces. Friends of the Mississippi River and the National Park Service’s Mississippi National River and Recreation Area have created a State of the River Report. It details the quality of the water.

We find that excess sediment, bacteria, and phosphorus impairs the ecosystems and prevents recreation. Elevated levels of contaminants like PFOS and mercury have caused fish consumption guidelines to be put in place. 

Microplastic fibers, pharmaceuticals, triclosan-derived dioxins, and nitrate concentrations have all increased. The report suggests people avoid swimming within 48 hours of a rainstorm because this is when the most runoff occurs. Keep this in mind if you want to let your dog go out for a swim, too.

Agricultural runoff, sewage treatment plants, and industrial facilities contribute to these pollutants. The Midwest has thousands of acres of farmland. Harmful chemicals like pesticides and fertilizers run off into the Mississippi River. Additionally, industrial plants along the Mississippi River release dangerous chemicals into the water.

Pro Tip: If you’re brave enough to swim in the Mississippi River, make sure to keep an eye out for these Most Dangerous Creatures in the Mississippi River.

Holston River

Although the Holston River is much smaller than the Ohio and Mississippi Rivers, it’s one of the dirtiest rivers in the country. The Holston Army Ammunition Plant is the main source of pollution. It discharges RDX, a toxic chemical explosive, into the river.

The Eastman Chemical Company was fined in 2015 for dumping motor oil, wastewater, and acetic anhydride into the Holston River. In 2017, excessive flooding led to large amounts of sewage waste spilling into the river.

The Tennessee Department of Environment and Conservation issued a water contact advisory that cautioned swimmers, anglers, and boaters about getting into the water. Even though it only runs through Tennessee, the Holston River is dangerously polluted.

Harpeth River

Another Tennessee river that makes the list of dirtiest rivers in the United States is the Harpeth River. It flows approximately 125 miles from Rutherford County to the Cumberland River. The rapid development of Franklin and Williamson counties has negatively affected the Harpeth River because of an increase in sewage in the river. The city also uses the river for its water supply. The Harpeth River is too small to continue to provide the water this growing area needs. Water comes out, and toxic chemicals get poured in.

Harpeth River has been listed as “impaired” by the state of Tennessee because it doesn’t meet the state’s water quality standards for recreation and fish and aquatic life. The Franklin sewer plant is the main culprit. High levels of phosphorus pollution have led to dangerously low levels of dissolved oxygen in about 60% of the river.

In addition to the Franklin area, a lead-smelting plant near the Kirkland community also contributed to the pollution. Lead can lead to cancer and destroy aquatic life. The plant recycled used automobile batteries from the 1950s to the 1990s and caused irreparable damage to the river.

New River

The New River flows approximately 320 miles through West Virginia, Virginia, and North Carolina. Unfortunately, due to mining activities in this part of the country, the New River is heavily polluted with metal. Arsenic and mercury are two extremely dangerous chemicals found in the river.

Other sources of pollution include agricultural runoff and residential sewage discharge. This area has seen rapid growth, much like the Franklin area of Tennessee, and the increased population has harmful effects on the water supply. More trash, industrial drainage, and road salt runoff lead to the New River’s increased pollution. In fact, each of the four tributaries have traces of human-caused wastewater pollution.

The New River Gorge National Park and Preserve issues water safety reminders. One of them is to dispose of human waste at least 100 feet from the river and bury it at least six inches deep. The National Park Service asks guests to clean up their trash to reduce river pollution and keep the environment clean.

Calcasieu River

Located in southwestern Louisiana, the Calcasieu River only flows about 200 miles but still makes the list of the top seven dirtiest rivers in the United States. This bayou country is full of deep forests and rural acreage. Because the river passes through areas of petroleum refining and other industries, petrochemical wastes contaminate the river. Pipeline spills leak millions of tons of dangerous chemicals.

In addition, Lake Charles became a shipping hub during the 1930s and 1940s. The Calcasieu River flows through an area that has experienced rapid industrial development. This has led to excessive chemicals draining into the river for almost 100 years.

The sediment from the bayou and undeveloped land also contributes to the overall pollution of the river.

Savannah River

Finally, the Savannah River, which runs approximately 300 miles along the South Carolina-Georgia border, is one of the dirtiest rivers in America. Mercury and lead are two of the most dangerous chemicals in the river. Tritium, a radioactive pollutant, is also common.

DSM Chemicals in Augusta, a company that makes raw materials for plastics, is responsible for dumping millions of pounds of toxic waste into the Savannah River. The Savannah River Site nuclear weapons plant near Aiken, S.C., produces more than one-third of the plutonium for our country’s nuclear bombs. 

Waste dumping here has led to highly radioactive chemicals like tritium entering the Savannah River. Due to these dangerous chemicals, drinking water and eating fish from the Savannah River can be harmful.

How Can We Prevent River Pollution?

An increase in human population and industrial development has led to river pollution over the last 100 years. We might not have known then what we know now about harmful chemicals and environmentally-friendly power sources. But today, we do. We must prevent further damage and repair what we can to our nation’s waterways.

Keep Solid Waste Out of Waterways

When camping, follow the National Park Service guideline to bury human waste at least six inches in the ground and at least 100 feet from a water source. This ensures solid waste won’t run into the river after a heavy rainstorm. Never dump your tanks into a waterway. It’s dangerous to people’s health and illegal.

Use Organic Gardening Techniques

Large farms commonly use pesticides, herbicides, and fertilizers. However, agricultural runoff is one of the top causes of pollution in several rivers mentioned above. These harmful chemicals end up in the lakes, streams, and rivers that supply drinking water to millions of people. Use environmentally-friendly organic products that don’t cause a health concern to animals or people.

Dispose of Chemicals Properly

Although this relates more to industrial plants than to individuals, if you have any harmful chemicals, dispose of them properly. Dumping radioactive chemicals, nitrates, and phosphorus into waterways may be easier, but it kills plant and aquatic life and poses a health hazard to humans. You can find areas designated specifically to dump hazardous materials.

Pro Tip: We got to the bottom of Why The Missouri River Is So Brown.

Aerial image of a dirty river in the USA
The dirtiest rivers in the USA are not safe to swim in.

Do Your Part to Keep Our Rivers Clean

You may not think one person can do much to affect the overall health of a river like the Mississippi. And you’re right. But we have to start somewhere. If you do your part and your neighbor does his part, entire communities can affect change. The people of Franklin can work to bring about a cleaner, healthier water supply for their city. And as we travel, camp, and explore nature, we can all do our part to protect our nation’s waterways.

How can you do your part to keep America’s river clean? Tell us your tips in the comments!

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