The Mississippi River, the fourth longest in the United States and the third largest in the world, extends from west Minnesota to the south-eastern tip of Louisiana and the Gulf of Mexico, but does the Mississippi River mix with the Gulf of Mexico? The answer is more complex than it appears, and to understand the relationship between the two we need to take a closer look at the geography of the river from its start to its end.
At the start of its journey, the river carries a significant load of dissolved salts and other minerals like phosphorous, nitrogen, and calcium, all of which come into contact with various sources of coastal waterways, with freshwater streams being the primary contributor. Further downstream, the river continues to gather substances from the watershed and all other sources of input along its way to the end, which brings us to the Gulf of Mexico.
When the Mississippi River reaches its evacuation point and finally makes contact with the Gulf of Mexico, the result is an interesting mix of freshwater and saltwater. The saltwater from the Gulf has a substantial impact on the river, as the waters of the Mississippi become denser than the Gulf itself. Because of this, much of the fresher upstream water does not make it to the Gulf, and a significant amount of the saltwater is left behind. This phenomenon has been termed “contact mixing.”
According to scientists at the National Oceanic and Atmospheric Administration (NOAA), the contact mixing of the river and the Gulf of Mexico is what keeps the river healthy. It is estimated that rivers account for 70 percent of the world’s total freshwater supply, and the Mississippi River provides a great deal of this supply. By mixing the two, both ecosystems are kept in balance.
Experts also note that while most of the dissolved salts and minerals of the Mississippi River are unable to fully mix with the Gulf of Mexico, some of the elements that it brings into contact with the ocean manage to seep into the waters of the Gulf. The added phosphorus, nitrogen, and calcium not only help to maintain the health of the river, but according to scientists have a direct impact on the marine life within the Gulf by aiding the growth of marine organisms like oysters, clams, and mussels.
The Mississippi River has long been a major contributor to the health of the United States in many ways, and understanding the impact that its contact with the Gulf has on both ecosystems is essential in order to preserve its significance as a freshwater source and maintain the health of the Gulf of Mexico.
The Effects of Riverborne Pollutants
The Mississippi River is considered the “most polluted” of all large rivers in the United States, due in no small part to pollutants that make their way into the river’s waters from its 31 tributaries. The pollutants, including nitrates and phosphates, come from a variety of sources — industrial and agricultural facilities, as well as domestic and urban runoff — making their way into the river and ultimately into the Gulf of Mexico.
The presence of these pollutants creates an imbalance within the Mississippi River and the Gulf of Mexico, causing increased algal growth and nutrient-related water issues like hypoxia and anoxia. Studies have found that the Mississippi River is the cause for a “dead zone” in the Gulf of Mexico, an area of oxygen-depleted waters low in marine life due to excessive nutrient pollution from the river.
Researchers from the University of Minnesota have also concluded that the concentration of pollutants coming from the Mississippi is causing a long-term decline in water clarity, a decrease in number of edible fish species, and a marked decrease in the abundance of many aquatic organisms in the Gulf. They have hypothesized that if the effects of these pollutants continue unchecked, the impacts could become even more catastrophic.
It is clear that the pollutants found within the Mississippi River are having a serious impact on the health of not only the river, but also the Gulf of Mexico. It is therefore imperative that measures be implemented to address this issue of water quality, in order to better safeguard the integrity of both ecosystems.
Strategies to Enhance Water Quality
A number of strategies have been proposed by scientists to address the issue of water quality and improve the conditions of the Mississippi River and the Gulf of Mexico, with the aim of mitigating the long-term costs associated with the decline of aquatic life.
One proposal advanced by researchers is nutrient trading, which allows those who are able to reduce the amount of a pollutant entering the river to receive credits for those reductions, which can then be traded to other parties who are not able to meet their pollution reduction goals. This provides an incentive for improving water quality, and gives those lacking the resources to clean up their share of the pollutants a way of making up for their inaction.
Other strategies could include further restrictions on the emission of pollutants into the river, more stringent regulations on pollutant-producing industries, and the implementation of education and awareness campaigns to limit the input of pollutants into the waters of the Mississippi.
Whichever strategies are ultimately chosen, it is clear that both short-term and long-term solutions are necessary if the health of the Mississippi River and the Gulf of Mexico is to be preserved for future generations.
Benefits of Improved Water Quality
The benefits of improved water quality from the Mississippi River are considerable, with improved fishing conditions being among the most significant. As mentioned before, the regional economy in the Gulf of Mexico is largely dependent on fisheries, and the presence of pollutants and other contaminants in the water has a direct effect on fishing.
Preliminary research by NOAA has found that if the levels of pollutants in the Mississippi and its tributaries were to be reduced, the number of fish species available for consumption would increase, opening up new economic opportunities and improving the livelihoods of many fishermen in the region.
Improving water quality could also result in an abundance of other species of marine life returning to the Gulf’s waters. The presence of these animals, such as dolphins, sea turtles, and seabirds, could have a positive impact on tourism in the area and possibly revive some of the region’s fishing villages.
The improvement of water quality could also benefit nearby coastal communities. The improved conditions could bring with them cleaner and safer drinking water, better recreational opportunities, and the possibility of increased property values.
The potential benefits of improved water quality in the Mississippi River and the Gulf of Mexico cannot be overstated, and serve to make it even more necessary that solutions to this issue be implemented quickly and effectively.
Conclusion
In conclusion, it is clear that while the contact mixing that occurs between the Mississippi River and the Gulf of Mexico plays an important role in keeping the river healthy, the presence of riverborne pollutants is having a seriously detrimental effect on the health of both the river and the Gulf. It is therefore imperative that strategies be implemented to address this issue and reduce the amount of pollutants entering the river, in order to improve the water quality of the two ecosystems and reap the benefits that come with it.
