The Mississippi River is the fourth longest river system in the world, and one that has been captivating hearts and minds since well before the dawn of recorded history. The river has long been a major transport route, providing a gateway to exploration for European settlers and a vital lifeline for Native American tribes.
Although many aspects of the Mississippi River’s grandeur and history are relatively well-known, few people consider the question of how high above sea level it actually is.
According to the U.S. Geological Survey’s National Hydrography Dataset, the Mississippi River has an average elevation of 13.1 feet above sea level, with its lowest point occurring at its terminus in the Gulf of Mexico (approximately two feet below sea level). At its highest point near Lake Itasca in Minnesota, the river rises to an elevation of 2,297 feet above sea level.
In terms of the geology of the area, much of the area through which the Mississippi River passes is made up of limestone and sandstones, formed during the Mesozoic era some 220 million years ago. Despite its length and vast drainage basin, the Mississippi River has an incredibly low gradient, moving at an average of around 3 feet every mile.
Chad Pope, a local water resources expert, notes that “the Mississippi River’s low gradient is what makes it such a slow-moving river, and allows it to be navigable. This is a key factor that has enabled the river to play an important role in transportation, energy production and recreation for centuries.”
To better understand the river’s elevation, it’s important to consider the overall landscape of the North American continent. Much of the region is characterized by gently rolling hills, known as the Interior Lowlands. Many of these hills are covered in thick layers of sediment, deposited by the Mississippi River over thousands of years. This sediment has all but leveled off the contours of the land, reducing the features to near-perfect flatness.
“The sedimentary layers in the region are part of what has enabled the river to traverse so many miles at such a low elevation,” says Pope. “And that low elevation, in turn, has helped make the Mississippi River a safe, reliable and necessary feature of the landscape.”
Political Impact
The Mississippi River has often served as a source of friction between states, tribes and the federal government. Political battles over the rights to the river and its resources have been raging since the early 19th century, when the Supreme Court ruled that states along the river have “riparian” rights – that is, they have the right to use (or withdraw) waters from the river.
Since then, numerous treaties have been signed to protect the rights of adjacent states, tribes and other stakeholders, as well as preserve the river’s ecosystems and prevent pollution. To this day, states such as Wisconsin, Minnesota and Illinois continue to cooperate on federal water protection programs.
Today, the Mississippi River remains a major source of income, transportation and recreation. As such, preserving and protecting the river is of paramount importance to many states, tribes and communities. According to Pope, “The elevation of the Mississippi and its low gradient is an important factor in helping the states negotiate the delicate balance between exploitation and preservation of the river and its resources. Without this low elevation, the balance may be much more difficult to maintain”.
Environmental Impact
The Mississippi River’s low gradient and elevation have also had a major impact on the river’s environment, both positive and negative. While the region’s low hills allow for easy transportation and recreation, they also act as a sort of “soak-away”, allowing sediment and polluted runoff to settle with little resistance. As such, riverside habitats for numerous aquatic species are often deoxygenated, creating low-oxygen areas that can be extremely detrimental to sensitive species.
Furthermore, the region’s low elevation makes it more susceptible to the effects of flooding than most other places, as water can quickly and easily overflow onto nearby areas. While certain measures are in place to help manage and mitigate the effects of flooding, many communities along the Mississippi River continue to suffer the effects of recurrent flooding today.
Pope states that: “The presence of low hills and a low gradient is certainly a strong suit of the Mississippi River and a major reason for its success as a transportation and recreation route. However, the river’s low elevation also means that it is particularly vulnerable to both flooding and water quality impacts, necessitating stronger management and conservation efforts to balance its exploitation and protection.”
Economic Impact
The Mississippi River’s low gradient and elevation over the years have allowed for a number of developments along its banks, both for commerce and recreation. Countless cities and communities have flourished in or near the river, providing employment and recreational opportunities for millions of people.
The availability of water has also allowed industrial operations to be established along the banks of the river, ranging from agricultural centers to energy production facilities. In addition, numerous locks and dams along the river provide reliable navigation and energy production, providing the vital energy necessary for many communities and industries.
The Mississippi River has no doubt played an important part in the economic success of the states it runs through. As Pope puts it, “The Mississippi River’s low gradient and ground elevation has enabled the state to take full advantage of the river’s resources, from tourism to commerce. This has been a major boon for business, both large and small, and has enabled the state to expand and develop in a number of ways.”
Cultural Impact
In addition to its economic and environmental importance, the Mississippi River has been a major source of culture and tradition for many generations. Throughout the river’s history, Native American tribes have regarded the river as a source of food, transportation and spiritual inspiration. Furthermore, the river has served as a source of comfort and refuge for generations of African Americans, providing a safe haven and a new start during some of the United States’ darkest days.
Today, the river remains a major source of celebration and growth for millions of people, from large cities to small settlements. As Pope notes: “The Mississippi River’s low gradient has allowed for pleasure as well as practical uses. It has been a major source for recreation for generations, allowing people to appreciate its beauty and heritage up close, or simply take a leisurely boat ride along its banks.”
Future of the Mississippi
Considering the river’s key role in the history and culture of the United States, the question of how to protect, manage and develop the river responsibly remains an important one. Increasing development and larger urban centers have placed new and unprecedented stress on the river, while rising sea levels have complicated its navigation.
One of the most important steps is to improve navigation and reduce flooding, while also preserving the river’s sensitive habitats and ecosystems. This will require the implementation of newer, more effective management practices, as well as improved collaboration between stakeholders. As Pope puts it, “The importance and relevance of the Mississippi River extends well beyond economic considerations. In order to ensure it stays safe and relevant for future generations, we must redouble our efforts to preserve, restore and develop the area responsibly.”
Impact on Local Communities
The Mississippi River has long been a major source of livelihood for local communities in the United States, both in terms of commerce and recreation. From fishing to boating to transportation, the river has enabled millions of people to make a living from its resources, providing them with income, food and security.
Today, however, the river’s future is uncertain. As development and urbanization continue, the river’s low gradient, coupled with its slow speed, makes it highly susceptible to pollutants, which can have far-reaching environmental impacts. In order to protect this vital resource, local communities must be better informed and engaged in conservation efforts.
Pope contends that, “The Mississippi River’s low elevation and gradient require compassionate and thoughtful management and preservation. Local communities must be engaged in order to ensure that our grandchildren will have the chance to enjoy the many natural and economic gifts that the river has to offer.”
Conclusion
All in all, the Mississippi River’s low gradient and elevation have played a major role in its success as a transport route and major source of livelihood for many communities. However, its low elevation and slow speed also make it vulnerable to pollution, runoff and flooding, necessitating both improved management and greater understanding from local communities.
