What Happens When the Mississippi River Freezes Over?

Written by Megan Martin
Updated: December 19, 2022
© iStock.com/juliannafunk
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Have you ever wondered what would happen if the second largest river in the United States froze over? It turns out you don’t have to wonder! Although it’s a rare phenomenon, there have been times when the Mississippi River had completely frozen over. In some instances, people were even able to walk across the river

Ready to learn what happens when the Mississippi River freezes over? Let’s dive in!

The Last Time the Mississippi River Froze Over

Freezing was common in the earliest parts of the 20th century and the end of the 19th century.

©Milen Mkv/Shutterstock.com

Because of the amount of human infrastructure on the Mississippi River, it doesn’t freeze over often. However, in the early 20th century, freezing over wasn’t too uncommon. It also wasn’t catastrophic, either.

That part can be a bit surprising. After all, with a major river like the Mississippi, it seems like any changes can completely alter how we live our lives, especially in the time before planes and cars were fully accessible. While the freezing of the Mississippi River did disrupt some travel, since only portions of it froze, there weren’t any vast negative effects. Once the weather cleared up – and thus warmed up – the Mississippi River thawed and melted before continuing to flow like it always has.

However, while the river is frozen, there are some interesting things that occur. First, while it is safe to walk on when frozen to a certain degree, it’s not exactly what you’d expect. Most notably is that the ice “sings.” While people were walking across the ice in the 1800s and the 1900s, the ice would echo certain high-pitched sounds back and forth, which could be heard above. 

Freezing was common in the earliest parts of the 20th century, as well as the end of the 19th century. Here the water would freeze completely solid, enough so that people could walk across it. However, after the Alton Lock and Dam were completed, the amount of freezing decreased because of the new ability to manipulate the flow of water in certain areas. 

What’s it called when the Mississippi River freezes over?

Mississippi River - New Orleans
When the Mississippi River freezes over, it’s called an ice gorge.

©Sean Pavone/Shutterstock.com

The Mississippi River actually has a fairly unique process when it freezes over. As a result, it also has a unique name! You see, when the Mississippi River freezes over, it’s called an ice gorge.

In this phenomenon, piles of ice form and stack on top of each other. It’s said that these stacks of ice can rival the height of a church steeple! In some areas, ice gorges can be as large as almost 1000 feet thick, although you won’t find these types of gorges near the Mississippi River. 

Does the Mississippi River freeze over often?

Mississippi River Marsh
Nowadays, the Mississippi River does not freeze over often.

©iStock.com/Jaimie Tuchman

When the Mississippi River freezes, it doesn’t freeze all at once. Instead, certain areas of the river will completely freeze over. While this isn’t necessarily a common event, it isn’t all that rare either. In fact, it’s estimated that the Mississippi River froze over in St. Louis at least ten times between the years 1891 and 1938. 

Nowadays, however, you won’t hear about the Mississippi River freezing over often. This is because it doesn’t, especially because of human influence on the river. 

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About the Author

I'm a writer with almost five years of experience. I recently graduated from Wingate University with a Bachelor of Arts in English and a double minor in biology and professional and technical writing. I love everything animals and nature related! The American kestrel is my favorite animal, but I also like sharks and alligators. In my free time, I like to watch documentaries and explore nature.

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  2. History 101, Available here: https://www.history101.com/day-mississippi-river-froze/