Analyzing the Effects of the Mississippi River on
The Dead Zones in the Gulf of Mexico

Dead zones in the Gulf of Mexico have reached about 8000 square miles. Dead zones are oxygen depleted areas in the ocean in which the levels of oxygen in the water are so low that it cannot sustain sea life. These dead zones are created by water runoff from the mighty Mississippi River. Nutrients in the water that run out into the gulf cause an abundance of algae growth. The alga then dies and as it sinks to the bottom of the ocean is decomposed by bacteria reducing the oxygen levels in the water. This coupled with the fact that the fresh water acts as a barrier between the salt water and the atmosphere preventing it from being oxygenated, is the primary cause of these massive dead zones. These dead zones, primarily the one in the gulf have increased in size drastically in the past decades and researchers are desperately trying to find a way to reduce their size. For the most part, nutrient levels in the river are naturally occurring, but there are some human factors in the rising levels causing increasing growth in the size of the Gulf of Mexico dead zone. Dead zones are nothing new. They have in fact been occurring for some time in history. Natural nutrients that come from rain water runoff from the mountains and streams along the Mississippi River have always run off into the gulf causing this natural phenomenon, especially in years with high rainfall. Throughout the years though, the amount of nitrate and fertilizer use have increased the levels of nutrients in the water, thus causing extreme growth in dead zones along the coast. This is only made worse with the increasing amount of manmade pollution that is put into the river, leading to increased efforts to clean the water before it reaches the gulf. Efforts have and are being made to eliminate the levels of nitrogen pollution in the water, but even with the best practices today the levels are still too high. As you would expect the aquaculture is greatly affected by the existence of these dead zones. Organisms like clams and mussels cannot exist and oxygen levels are too low for slow moving life forms like lobster, crab, and other shellfish to survive. For faster moving sea life though, it does mean death…or at least immediate death. Studies have shown that in fish living in the area of dead zones, there is drastic reduction in the size of reproductive organs, decreased spawning habits, a noticeable reduction of eggs produced by females, and decreased levels of hormones. Although hurricanes are nature’s way of combating this fault in the ecosystem, it doesn’t entirely fix it. Hurricanes act as natural mixers, stirring up and combining the fresh and salt water bodies to naturally oxygenate the gulf water. The random occurrence of hurricanes combined with the increasing amount of nutrient levels found in the water have made even nature’s fix useless today. The EPA struggles to find ways to lower the levels of nitrogen pollution and even their best efforts aren’t working anymore. I would propose some mechanical way of drawing salted gulf water in and mixing it with fresh river water before it reaches the gulf. Large mixing stations would have to be constructed in order to intake enough water to mix with the river water before being routed to the gulf. Another way could be to construct mechanical aerators in the dead zones to pump oxygen into the water. This idea is comparable to your fish tank at home. These solutions sound good, but the core mitigation is simply just to greatly eliminate the amount of pollution we allow to get in to the water in the Mississippi River. The more we clean up our waste water and our impact on the ecosystem the more likely that the dead zones decrease in size and sea life populations start to increase.