{"id":13341,"date":"2024-01-22T16:45:10","date_gmt":"2024-01-22T15:45:10","guid":{"rendered":"https:\/\/www.aboutriver.com\/?p=13341"},"modified":"2024-01-22T16:45:10","modified_gmt":"2024-01-22T15:45:10","slug":"what-happens-when-the-mississippi-river-flows-backwards","status":"publish","type":"post","link":"https:\/\/www.aboutriver.com\/what-happens-when-the-mississippi-river-flows-backwards\/","title":{"rendered":"What Happens When The Mississippi River Flows Backwards"},"content":{"rendered":"
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The Mississippi River is one of the longest rivers in the United States, spanning over 2,300 miles from the northern tip of Minnesota to the Gulf of Mexico. But what happens when the river starts to flow in the opposite direction?<\/p>\n

At certain times, the Mississippi River may experience what is called a “reverse flow” – when the water starts to flow upriver instead of down. This can occur due to factors like flooding, rapid snow melt and heavy rains, when the water levels on one side of the river become too high and can no longer keep up with the water levels on the other side. It’s estimated that reverse flow can occur for up to 200 miles upriver. This can affect both the quantity and quality of the water in the river as it flows upstream, as well as the health of the river habitat.<\/p>\n

The presence of sewage, chemicals, pesticides and other pollutants running upstream can cause environmental damage and present risks to the public. There is a risk of these pollutants being pushed into the areas they are flowing by, while sewage and contaminated water can easily seep into drinking water sources. Furthermore, when the river starts running in the opposite direction, the flow of the water can become so strong it affects the accessibility of navigation locks, affecting trade, transportation and tourism.<\/p>\n

In order to determine the extent of a reverse flow, experts typically look at “trough departures” in the region. These are the differences between the average trough of the river’s flow and the actual height of the river at any given moment. If the difference exceeds a certain threshold, the reverse flow has begun. Once the reverse flow has started, the current must be monitored for a prolonged period of time before it can be declared over.<\/p>\n