Between the construction of levees all along the banks of the Mississippi River from Louisiana to Minnesota, the construction of MRGO (Mississippi River Gulf Outlet) and the dumping of pollutants that kill off the natural plants that hold together barrier islands, it is indisputable that the United States as a whole, and in particular the federal government, have contributed mightily towards the destruction of Louisiana's coastal ecosystem, creating the single-greatest threat to endangered species, migratory birds and the environment in general in the United States of America. Additionally, the federal government has declared Louisiana's offshore oil wells as federal property, keeping all of the money generated by the drilling --- yet another major cause of the destruction of the coastal wetlands and ecosystem.
Therefore, the United States Congress should take responsibility for the consequences of the actions undertaken by the U.S. federal government, and commit to providing the monetary resources necessary to repair the damage and create a sustainable coastal model going forward.
"Benefiting our nation since the founding of New Orleans, today the region provides approximately 30% of our nation’s fisheries, and 30% of the nation’s oil and gas supply. The coast that protects these valuable resources must be saved!"
"Human disturbance has had a massive impact on the balance of wetland growth and decline. Since the colonization of America, over half of the original wetlands have been lost. In modern times and with the increase in available technology, this loss has accelerated geometrically. In the past 100 years, Louisiana has lost 20% of its wetlands, representing an acceleration of 10 times the natural rate.
"The main forms of human disturbance are the river-control structures such as dams and levees, the dredging of canals, and draining and filling... The largest and most destructive example of this dredging is the Mississippi River Gulf Outlet (MRGO). Created in the 1960’s to facilitate the passage of ships to the Gulf of Mexico, the canal destroyed over 23,000 acres of wetland. The MRGO has now grown to 2 ½ times its original size and costs the government $7.6 million a year to maintain. Experts say that canals now account for 6.8% of Louisiana’s wetland area."
"Eutrophication is another major problem facing Louisiana’s wetlands. Caused by chemical and industrial pollutants, human waste and agricultural runoff, eutrophication literally means “overnourishing.” The excess chemicals present cause the wetland plants to die, breaking the marsh apart. In addition to these more indirect effects, human effect the wetlands by draining and filling them, destroying them for commercial use, and dumping pollutants directly into them."
"Since construction of the MRGO and other canals that are intended to increase access and improve navigation in the area, average salinity levels have risen in coastal Louisiana. The MRGO, or Mississippi River Gulf Outlet, breaches the barrier islands, which serve to shelter coastal wetlands thus exposing once protected areas to the full effects of salt intrusion. In 1989, the MRGO canal was 3 times larger in width than at original construction due to coastal erosion that resulted from activity along the canal. Although the MRGO has been closed, it is still conveying salt water into the wetlands and salinity levels continue to rise, though not as rapidly." Source: http://lab.visual-logic.com/2010/02/saltwater-intrusion-mrgo/
"By 2050, if nothing is done to stop this process (Coastal Erosion), the state (Louisiana) could lose another 700 square miles, and one-third of 1930s coastal Louisiana will have vanished. Importantly, New Orleans and surrounding areas will become ever more vulnerable to future storms. “New Orleans can’t be restored unless we also address coastal and wetland restoration too,” says Craig E. Colten, a geographer at Louisiana State University (LSU)."
"Today, South Louisiana is one of most intensively engineered places in the nation. Vast quantities of water are diverted or rerouted through a lacework of navigation corridors held in place by 2,000 miles of earthen, rock, and concrete levees. Walled off from the floodplains, the river can no longer provide enough silt to the delta to keep up with natural subsidence and sea level rise. About two-dozen dams also hold sediment back from the river and its tributaries. “We have tamed the river for the almost exclusive benefit of navigation,” says David R. Conrad, a senior water resources specialist with the National Wildlife Federation.
The construction of high levees did end the spring floods along the lower Mississippi, but at an environmental cost, eventually eliminating many of the wetlands, floodplains, and barrier islands of the delta. “When you lose wetlands and flood-plains, you lose their natural services including storage capacity during floods, and when you lose coastal wetlands, you lose wave and storm protections,” says Sandra Postel, director of the Global Water Policy Project, a nonprofit organization based in Amherst, Massachusetts. “Katrina in South Louisiana was an example of what happens when you disturb the natural infrastructure.”
In November 2005, the National Academies released a report, Drawing Louisiana’s New Map: Addressing Land Loss in Coastal Louisiana. The report notes that building and maintaining levees and dams along the Mississippi River was a “more or less ubiquitous” cause of wetland loss."
"The Mississippi River Gulf Outlet, a little-used 40-year-old shipping channel connecting the Gulf of Mexico to the Mississippi River, is believed to have served as a funnel for Katrina’s storm surge. The navigation channel and the eastern levee of the Mississippi River seem to have directed high water into the Breton Sound estuary southeast of New Orleans, according to Greg Steyer, a USGS wetland scientist. From there, the surge poured into Lake Pontchartrain and an industrial canal, where it overwhelmed levees, contributing to flooding in St. Bernard Parish and the Lower Ninth Ward of New Orleans. Like the oil and gas canals, the outlet also allows saltwater intrusion and tidal action into freshwater ecosystems, killing vegetation and turning the marsh into a stretch of open muddy water."