This article is excerpted from Wave Maker’s News, our quarterly update on all things water in the Gulf of Mexico, check out the full newsletter here. Satellite image of sediment plumes coming from the flooded Mississippi River, taken on May 17, 2011. Photo courtesy of NASA.Due to heavy rains and snow melt from North Dakota to Minnesota to New York, we have seen record-setting flood levels throughout the Lower Mississippi River Basin. This flooding has pushed the levee system to its limits, but it seems that the system has done what it is supposed to do. Part of utilizing the Mississippi River Levee system has meant the opening of three floodways: the Bird’s Point Floodway in Missouri, the Morganza Floodway in Louisiana, and the Bonnet Carré Spillway, also in Louisiana. The opening of these floodways has inundated farm land and residential property, but relieved the pressure of the floods on some urban centers, including Cairo, IL, Baton Rouge, LA and New Orleans.Regretfully, the levee system that has protected many communities from Mississippi River flooding will likely exacerbate this year’s Dead Zone in the Gulf. Before the levees were built, when the River flooded routinely, it would spill into its floodplains and surrounding wetlands. These floodplains would slow the water down, help filter out pollutants, and store the floodwater. Now with these levees, the channel acts as a syringe, injecting the Mississippi and the pollutants it contains straight into the Gulf. Very simply, more pollution (specifically nitrogen and phosphorus) equals a bigger Dead Zone. As our readers may know, the Dead Zone is an area in the Gulf at the mouths of the Mississippi and Atchafalaya Rivers that has oxygen levels so low that aquatic life must swim away or suffocate. The nitrogen and phosphorus pollution that causes the Dead Zone each summer comes from various sources, but the largest contribution comes from runoff from agricultural fields in the Midwest. Combine this runoff with high rainfall, and we see higher loads of this Dead Zone-causing pollution in the swelled Mississippi. Last month, scientists have released a prediction on the size of this year’s Dead Zone. Their models predict the largest Dead Zone ever measuring 9,400 square miles, or roughly the size of Lake Erie.It is past time that the Federal Government and states step up their game in addressing the Dead Zone. Up until now, we have only seen underfunded voluntary programs utilized to address the agricultural nitrogen and phosphorus pollution issues in the Mississippi, and we have only seen the Dead Zone get bigger. Despite the anti-EPA atmosphere in Washington, D.C., it is imperative that EPA take decisive action. Back in 2008, GRN, along with the Mississippi River Collaborative, formally petitioned EPA to develop numeric limits to the nitrogen and phosphorus pollution in the Mississippi, as well as a concrete plan to reduce this pollution in the River. Almost three years later, EPA has not even responded to our petition, but GRN and the Mississippi River Collaborative will continue to fight for a truly effective solution to the Dead Zone that plagues the Gulf every summer.Matt Rota is GRN’s Director of Science and Water Policy.
