The majestic Mississippi River is a system of rivers and tributaries that has shaped the geography of the United States since its early settlement by Europeans. Spanning 2,350-miles in length, and traversing no less than 10 states in its course, it is the second longest river in the US after the Missouri. Its average depth is reported to range from between 6.4 ft (1.9 m) to 10 ft (3.0 m), and its deepest measured point is at 200 ft or 61 m. But how deep does it get?
The first settlers in the Mississippi Valley, who were drawn to its fertile soils, often attempted to estimate its depth by throwing weighted pieces of wood and other objects into its waters. According to one source, a Sir Robert Montgomery of Scotland calculated in 1797 that the deepest part of the river was over 170 fathoms (about 1010 feet), and the average depth was much shallower at eight fathoms (48 feet).
Today, modern studies of the Mississippi River have led to more accurate and reliable estimates of its depth. According to the U.S. Army Corps of Engineers (USACE), its mean depth is 13.8 ft (4.2 m), with a maximum reported depth of almost 200 ft (61 m). The deepest recorded point of the Mississippi River is beneath a dam at Louisiana, where it is reported to be a 137-ft (42 m) deep.
The USACE further reports that the Mississippi River has a specific gravity of 1.02, which is 10 percent greater than that of the nearby Gulf of Mexico. This phenomenon is believed to stem in part from the fact that a great deal of the water in the river is delivering sediment downstream from small rivers that enter from the North, and from rain water from larger watersheds farther upriver.
The Mississippi River represents an important source of freshwater to many of the humans and animals that live in its vicinity. The river supports more than 1,000 different species of fish, birds and other wildlife, and it serves as the main source of drinking water for most of the region’s estimated 230 million people. Moreover, its reflective waters provide a beautiful visual testament to its importance and its power.
Changes Over Time
Though the depth of the Mississippi River has remained relatively stable over time, its course has shifted drastically. This is due at least partly to the fact that the river carries a whopping 500 million tons of sedimentary material each year. Tributaries, such as the Missouri and Ohio Rivers, also introduce a great deal of water and sediment into the Mississippi, throughout the year. Over time, these elements, combined with the devastating effects of natural disasters such as floods, have caused the Mississippi River to change its course throughout the centuries.
In fact, the Army Corp of Engineers estimates that the bed of the Mississippi River has moved more than 600 miles from its original course since its formation around 6,000 years ago. This dynamism has caused the Mississippi River to create new landmasses such as the wetlands to the east of New Orleans in the past, and could potentially lead to the disappearance of the Delta in the nearby future.
Therefore, while the depth of the Mississippi River has stayed relatively constant over the years, its course has shifted considerably. This also suggests that the boundaries and structures of the river aren’t fixed, and are constantly changing as sediment is added to and taken away from the river’s course.
Dams and Levees
The presence of dams and levees along the course of the Mississippi River is one of the primary factors influencing its depth. There are currently 29 major dams spanning along the river and its tributaries, with the majority of them located in the upper course of the river, between Minnesota and Louisiana.
The presence of these dams affects the depth of the Mississippi River in two ways. First, it reduces the velocity of the water, and second, it captures and stores sediment within the reservoir created by the dam. On one hand, this reduces the potential for flooding downstream, and, on the other, it reduces the amount of silt that usually gets deposited in the riverbed.
In addition, levees, which are built in order to prevent flooding, also affect the depth of the river. The levees, which can be of either earth or concrete construction, are narrow walls that are built along the banks of the river. They generally act as a physical barrier to the flow of the water, which can sometimes lead to a deeper and narrower riverbed. Additionally, levees also prevent large amounts of sediment from being deposited in the river, leading to even deeper waters.
Overall, the presence of dams and levees along the Mississippi River has a significant impact on its depth. While the dams reduce the amount of sediment that enters the river and reduce the velocity of the water, the levees act as a physical barrier to the flow of the water and create a deeper and narrower channel.
Environmental Concerns
The changes in the depth of the Mississippi River due to the presence of dams and levees have also brought about various environmental concerns. Many of the dams built along the river are considered to be unsustainable in the long run, due to their impact on the aquatic life, and the spread of pollutants.
The potential negative impacts of the dams and levees are wide ranging and include disruption of the natural migration of fish, reduced sediment transport and deposition, alterations in the chemical compositions of the river, and increased water temperatures due to the presence of the structures. Additionally, the presence of the dam walls can disrupt the floodplain and disrupt the natural flow of the river, leading to an increase in the risk of flooding in other areas.
Moreover, it is believed that the presence of dams and levees also affects the flow of energy in the river, leading to a decrease in the ability of the river to transport and store sediment. This decrease in the sediment transport and deposition could also lead to a decrease in the depth of the river over time.
In conclusion, the depth of the Mississippi River is an ever-evolving phenomenon that is affected by numerous factors, with human activity playing a large role. The depth of the water is estimated to range between 6.4 ft (1.9 m) to 10 ft (3.0 m), but it could vary depending on the presence of dams and levees, as well as its proximity to smaller streams and tributaries. By understanding how this great river works, and the potential effects of human activity on its waters, we can ensure that its resources are properly managed and protected for future generations.
Impact on Local Ecosystems
The depth of the Mississippi River also has an extensive impact on the local ecosystems, as it affects numerous aquatic species that inhabit the river. The fish, shrimp, and other species that originate in its waters are heavily dependent on the river for their reintroduction and offspring production during their life cycle.
The shallow waters of the Mississippi River also make it vulnerable to the introduction of invasive species, which can occasionally make the native species go extinct in isolated regions. This is often a result of stocked fish that were originally meant to restock the river being introduced from other areas and continents.
Additionally, the deeper waters of the Mississippi River also provide a natural habitat for many of the fish species. Some of the larger species, such as catfish, sturgeon and paddlefish, inhabit the deeper waters of the river, where they can spawn their young in the warmer waters. This is an important source of food for many of the mammals and birds native to the region.
In summary, the depth of the Mississippi River has a direct impact on local ecosystems. The shallow areas of the river are especially vulnerable to the threat of invasive species, while the deeper areas provide vital resources for native fish species and other aquatic life.
Conservation of Resources
The conservation of the Mississippi River and its resources is vital to the health of the ecosystem, and many techniques have been deployed in order to ensure that the waters are kept clean and healthy.
Due to its strategic location, the Mississippi River is heavily utilized for shipping, transportation, and recreation. Vessels frequently move along the waters, carrying cargo and passengers, releasing a variety of pollutants in the process. Additionally, shoreline landscapes are heavily developed as people build homes and businesses, which can also introduce pollutants into the water.
The USACE, along with the Environmental Protection Agency (EPA), has employed numerous measures in order to protect the Mississippi River from pollutants and other environmental impacts. These include strict regulations on the types of vessels that can travel on the water and the overall quality of water they must adhere to. Furthermore, certain sections of the river undergo regular water quality tests to ensure that their water quality is maintained.
Therefore, conservation of the Mississippi River is of utmost importance, and the USACE and EPA are taking careful steps in order to ensure that the water remains clean and healthy for generations to come.
Final Thoughts
The depth of the Mississippi River has been subject to various changes over the decades. While its average depth is reported to range from between 6.4 ft (1.9 m) to 10 ft (3.0 m), its deepest measured point is at 200 ft or 61 m. This is due at least partly to the fact that the river carries a whopping 500 million tons of sedimentary material each year, combined with the devastating effects of natural disasters such as floods. The presence of dams and levees along the course of the river also have a significant impact on its depth, reducing the velocity of the water and capturing and storing sediment on the reservoir they create.
Moreover, the changes in the depth of the Mississippi River due to the presence of dams and levees have also brought about various environmental concerns. These potential negative impacts include disruption of the natural migration of fish, reduced sediment transport and deposition, alterations in the chemical compositions of the river, and increased water temperatures due to the presence of the structures. Therefore, the conservation of the Mississippi River is of utmost importance, and the USACE and EPA are taking careful steps in order to ensure that the water remains clean and healthy for generations to come.
