Why Is the Mississippi River Drying Up?

The Mississippi River's water levels are the lowest they have been in a decade.

The river is the second largest in the U.S. and provides drinking water to around 20 million people but as water levels continue to decline, this integral water source could be at risk.

Particularly low water levels have been recorded in Memphis, Tennessee, where levels have dropped to as low as -6.1 feet as of November 15.

In October, Tower Rock—an island in the middle of the Mississippi River in Missouri—became accessible by foot for the first time in living memory. Water levels were so low people were able to walk to the island rather than take a boat as usual.

It is not the only anomaly to occur as the river dries up. The sunken remains of a 19th-century trading ship—previously covered by the river's waters—were discovered in Baton Rouge, Louisiana.

Even relics and artifacts from the American Civil War have been discovered on the river banks.

Riley Bryant, from Memphis, shared videos of him finding Civil War-era bullets and an intact belt buckle from the river.

Why Is the Mississippi River Drying Up?

Parts of the U.S. have been in the grips of an ongoing megadrought. The Mississippi River is just the latest body of water to be affected by the dry conditions.

"Around 1/3 of rainfall in the U.S. ends up in the Mississippi River, and with decreased rainfall in the Midwest, there is less water entering the river to begin with," Alexander Loucopoulos, Partner of Sciens Water and Chair of the Mississippi River Cities and Towns Initiative (MRCTI)'s Corporate Advisory Board, told Newsweek.

It is suspected that climate change is the main reason for the ongoing drought.

But it is hard to tell for certain. Some scientists have noted that in previous years, the river has actually produced record water flows, meaning this could just be a one year issue.

If water levels continue to recede, however, the discovery of shipwrecks will not be the only result.

"The Mississippi River provides drinking water to around 20 million people, or 16% of the U.S. population. It's also a primary mode of transportation, carrying around 500 million tons of cargo every year," Loucopoulos said. "The Mississippi River Basin is home to 57% of US farmland, producing 60% of US grains and 54% of US soybeans. This interconnected network, spanning much farther than just the Mississippi River Basin, will be affected by this drought."

How Many States Does the Mississippi River Run Through?

The Mississippi River runs through ten states, namely Minnesota, Wisconsin, Tennessee, Iowa, Illinois, Kentucky, Missouri, Arkansas, Mississippi and Louisiana.

Although the river will probably never dry up entirely because of its size and not all of these states are in a severe drought, those that are may see narrower waterways as water levels continue to drop, which will in turn affect the routes of cargo ships.

Loucopoulos said that Louisiana, as well as Tennessee, have been particularly affected and the results of the drought are already being seen first hand in these states.

"Louisiana has been affected in a pretty big way, as it sits at the mouth of the river and has experienced first hand the impacts of saltwater intrusion at the Mississippi River Delta," he said. "There are already communities that have issued water advisories and are looking to desalination treatments to ensure steady drinking water supplies."

"Throughout many parts of the river, including Memphis, the Mississippi River has reached record lows," Loucopoulos said. "At one point there were 2,000 barges stalled due to low water levels. Low water levels mean less drinking water for the 20 million people dependent on the river, issues transporting crops and other goods on barges down the river and threaten availability of water for food production in the Basin. It's an interconnected system; you can't separate one issue from another."

What Is the Source of the Mississippi River?

The main source of the Mississippi River is Lake Itasca, a small glacial lake in Minnesota. From there, the river runs through to the Gulf of Mexico. But the effects of the drought could expand way beyond the states the river flows through.

"In short, if the drought continues, we will face issues in delivering clean drinking water, producing food, and transporting goods. Costs for all will increase, beyond just those living in the Mississippi River Basin," Loucopoulos said.

"The Mississippi River is the cheapest way to transport crops across the Midwest, but drought conditions have caused barges to decrease in number and carry less weight, in turn increasing costs," he said. "Drought impacts the amount of freshwater available along the entire river and its tributaries, which if prolonged will threaten the drinking water supplies and agricultural water availability for every community that is reliant on the Mississippi River."

"Saltwater intrusion into the Mississippi River further threatens our drinking water. This drought affects all sectors of society: health outcomes worsen when access to clean drinking water is restricted or cut off, companies will go bankrupt because they can't move their barges, and businesses will close."

How Long Is the Mississippi River?

In total, the river flows 2,350 miles.

"Since we don't have the power to control the weather, the best thing to do is to plan and prepare for the future," Loucopoulos said. "Federal funding for drought is extremely limited and needs to be supplemented by investments from the private sector. The economic impacts of failing to respond to this drought promptly and proactively could be massive.

"The number one solution is water reuse, which is essential to continued water security. By being conservative with water use now and building the systems that will allow us to operate with less available water going forward, we can be much more resilient in the face of drought."

The Mississippi River is not the only body of water in the U.S. to be affected by drought. Lake Mead, the largest man-made resevoir in North America, is also drying up because of severe drought conditions.

A multitude of discoveries have been made as the lake dries up, including sets of humans remains and shipwrecks.

Also, water levels at the Great Salt Lake in Utah are the lowest they have ever been.

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