Just How Bad is the Pollution in the Mississippi River?

The Mississippi River is one of the most polluted rivers in the entire United States. That part isn't necessarily a surprise. Like I did earlier this summer, I took a Dubuque boat cruise on the river with some friends this weekend, and at one point, just looked at how filthy, mucky, and ugly the water of the once-pristine river is.

Some outlets peg the Mississippi River as the second most polluted river in the country, but those metrics are difficult to quantify. Intuition and general knowledge of pollution suggests that the problem lies with the common offenders: cigarette butts, plastic soda rings, plastic bottles, and other junk...

While of course these elements sadly do find themselves in the Mississippi River, the problem is a lot more significant, and as a result, harder to stop.

For additional context: the Mississippi River is one of the largest rivers in the entire world. It borders Iowa, Illinois, and seven other states, and empties into the Gulf of Mexico. In 2022, it ranked sixth on American Rivers' Most Endangered Rivers list. It was its sixth appearance on said list since 1992.

The problem with the Mississippi River goes beyond conventional garbage pollution, per NPS.gov:

Stretches of the Mississippi River within the park corridor exceed water quality standards for mercury, bacteria, sediment, PCBs (polychlorinated biphenyl), and nutrients. Unfortunately, these "impairments" can make the water unsuitable for fishing, swimming, and drinking.

Nitrogen and phosphorous fertilizer runoff from Iowa and other neighboring farm states contribute to the significantly large "dead zone" that fails to support aquatic life, per The Des Moines Register and the aforementioned endangered rivers list. In 2022, the dead zone was about the size of the state of Hawaii.

To date, the Mississippi River supports about $400 billion in commercial activity, along with over one million jobs. This country is incredibly reliant on the Mighty Mississippi to flow, but the degradation has been slow, painful, and punitive.

The Earth Project further contextualizes the pollution problem in the river:

The brown color of the Mississippi River is caused by sediment and is the reason this large mass of water is often referred to as the Big Muddy. Fertilizer contaminants in the Mississippi are responsible for a dead zone of 6000 to 8000 square miles located where the river runs into the Gulf of Mexico.

This is why when the river dips below normal levels, or rises to the level where catastrophic flooding is imminent, the state of the Mississippi becomes a national story. The pollution levels are significantly concerning, but due to farming habits, there really is no clean nor imminent solution to fix it.

Read more about the state of Mississippi River pollution on The Des Moines Register's website.