The Mississippi River is one of the longest rivers in the world, spanning from Minnesota to the Gulf of Mexico, with vast parts of the USA covered by its hectares of water. As the ninth longest river in the world and the fourth largest in the United States, the Mississippi River’s total water level can be affected by multiple variables, from climate to engineering projects. While the variations in the water level are constant, the river’s mean water level is usually now always as high as it once was.
As the Mississippi River runs through many states, the water level has an effect on local habitats, wildlife, and industry such as barge transportation. On average, the water level of the Mississippi River is 44.3 feet above sea level at the Cairo Station in Illinois, according to the U.S. Geological Survey. This level varies due to weather-related fluctuations throughout the year, and was historically much higher. During the peak of the river’s highest levels in the 1910s, it reached up to 56.2 feet, and in 1997, it went as low as 23.9 feet. In comparison, 2019’s water level averaged at 44.3 feet.
The variations in the water level of the Mississippi River can be caused by extreme high or low climates. For example, a low climate is made up of below-average rainfall in the upstream areas near Canada and during drought conditions. Low rainfall in the upstream areas causes a drop in the water level downstream due to a lack of water supply. On the other hand, a high climate is characterized by flash flooding and high rainfall. This abnormally high water level in the river is caused by the increased runoff of water from the surrounding areas, and during major floods, the water level can rise up to 20 feet or higher.
The presence of human-made infrastructure along the banks and in the middle of the Mississippi River also lead to changes in the mean water level and the flow of the river. Dams and locks control the water level from upstream to downstream, and levees are built to prevent flooding from reaching the surrounding habitats. The usage of the river for transportation is maintained by the locks of dams, as the water level is kept at a desirable height for barges to traverse it. Furthermore, the height of the water is kept regulated to prevent flooding that could possible stop or halt all traffic on the river, affecting the accessibility of goods transportation and all resources downstream.
The fluctuations of water level helps to determine the extent and severity of flooding which occurs along the Mississippi River. Along with the natural and human-made features of the river, the degree of flooding is calculated using present rainfall in areas near the river. In the event of flooding, local and state officials have implemented flood controlling strategies such as investing in flood-preventing infrastructures, creating a network of monitoring locations and warning systems, as well as evacuation plans.
Economic Impact of the Water Level
The Mississippi River serves as an important link between the many states in its path and a major high-volume area for transporting goods. The high water level of the river aids in the barge’s mobility due to a greater flow which allows for the river to accommodate a larger capacity of goods. Keeping the water level high promotes its many benefits for the economy, with states such as Iowa and Arkansas making up to one-third of their entire economy from relying on the Mississippi River for goods transportation.
On the other hand, the low water level results in the dehydration of the fish habitats downstream. With a shallow river, the depths of water pools are not sufficient for fish to reproduce, which affects the biodiversity of these habitats. In addition, the low water level decreases the navigability of the river due to sandbars appearing, obstacles which create difficulty for barges to fill their usual transport capacity.
The Mississippi River also has an impact on the agricultural industry in the adjacent states. Flooding on the river can benefit the land around it and agriculturalists have adapted to the seasonal changes to plan their crops. Periodic flooding helps to deposit soils, supplying essential nutrients to the land which that can become limited over time. The water and sediment are also used to refill the depressions which become alternate wetland sites for migrating and breeding birds, an important indicator for the overall health of the ecosystem.
Environmental Benefits
The rise and fall of the Mississippi River’s water level helps to maintain the overall health of the river’s basin system by providing an adequate amount of water to refill wetlands, irrigate pastures and croplands, and supply cities and towns with drinking water. The differences in the river’s water level are beneficial for the habitats nearby, and for many species which rely on open floodplains for breeding and foraging.
The land around the Mississippi River is frequently flooded and drained, creating valuable habitats for countless wetland species. During floods, the deposition of sediment and organic matter on the substrate results in increased soil fertility, providing nutrition for plants which can help in the growth of nearby forests.
Other species of birds, reptiles, and small animals rely on the Mississippi River to replenish their habitats. They use the wetlands and open floodplains for foraging, nesting, roosting and migration purposes. The Delta marsh, for instance, provides a wide range of biological diversity for those animal species, including various waterfowl and wintering waterbirds.
Conclusion
The water level of the Mississippi River is always in flux, sometimes rising and sometimes falling. It is directly impacted by both natural causes and human-made engineering, which has a major impact on local habitats and reliance upon the river, such as the barge transportation industry and agricultural businesses. The Mississippi River basin is a crucial part of the United States, and understanding the risk of flooding, the importance of irrigation, and the habitation of diverse species due to the water level are all ways of preserving the river’s health.
