New Orleans, LA
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Re-engineering the Mississippi River will stem catastrophic economic and environmental losses from human development and climate change while raising billions of dollars in value, according to a report released yesterday.
The paper, titled "Answering 10 Fundamental Questions about the Mississippi River Delta," highlights the need to protect against land losses and preserve ecosystems along the Gulf Coast. Scientists and engineers from environmental advocacy groups and research institutions contributed to the report, noting that a quarter of the land on the bayou has eroded over the past 100 years, which they attributed to activities like damming the water for energy and flood control, dredging the riverbed for shipping and diverting the river for irrigation.
These actions halved the amount of sediment flowing into the delta to replenish the landscape, and if the process continues unabated, thousands of square kilometers of land will wash into the ocean, with more than $350 billion in losses over the next 20 years, according to the report. Meanwhile, sea levels are rising and weather events like hurricanes are becoming more extreme, accelerating the process and threatening to submerge cities like New Orleans.
This was described as having huge repercussions, not just for Louisiana but for the United States as a whole. "The Mississippi Delta is phenomenally important to the nation," said Sam Bentley, one of the report's co-authors and a professor specializing in sediment in the Department of Geology and Geophysics at Louisiana State University.
He explained that the region is critical for offshore oil drilling and is a transit route for close to 20 percent of America's shipping and navigation, particularly for grain from the Midwest. The waters provide one-third of seafood tonnage served in the United States, and many species spawn over the silt near the mouth of the Mississippi.
But the delta's 2 million residents have watched the sand beneath their feet washing away over the years, with no end in sight. The delta constantly gains and loses land, but losses have drastically outpaced gains.
A 2009 study by Michael Blum and Harry Roberts in Nature Geoscience found that the delta could lose up to 13,500 square kilometers of land by 2100. Many have already left the region, fearing for their homes and their jobs, in the aftermath of Hurricanes Katrina and Rita as well as the Deepwater Horizon oil spill.
'A state of environmental decline'
"[The delta is] in a state of environmental decline that threatens a large amount of commerce and ecosystem services," said Bentley, who co-authored the report. "Even if there were no climate change, even if we were in a steady state right now, the delta would continue to subside and erode into the ocean." This will raise fuel prices, hamper the economy, reduce biodiversity and threaten food security.
"By letting this system completely collapse, you lose a lot of those economically important species," said Alisha Renfro, a coastal scientist with the National Wildlife Federation. In addition, without the delta as a shield, the coast along Louisiana and Mississippi is more vulnerable to storms and saltwater intrusion.
The report calls for an all-out approach that includes mitigating the damage, restoring land and adapting to a new normal. "The situation is so dire that all the tools in the toolbox need to be used," said Angelina Freeman, a coastal scientist at the Environmental Defense Fund and a co-author.
One strategy is to mimic how the river picks up sediment upstream and deposits it on the delta. John Day, a professor emeritus in the Department of Oceanography and Coastal Sciences at LSU, said that upstream water can be routed into wetlands and then back into the river "to restart the natural function of the delta." Engineers can also construct bypasses that allow sediments to flow around obstructions like dams on the Mississippi.
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6 Comments
Add CommentSeems to me that we got ourselves into this problem by trying to tame the Mississippi in the first place. We did not understand the environmental consequences then and I doubt if we come close to understanding the consequnces of this plan either. Instead of adapting nature to our idea of the way it should be, I think we should consider adapting our own livestyles to nature instead.
Reply | Report Abuse | Link to thisWe should consider abandoning New Orleans and come up with a different plan that minimizes man's impact on the delta. A port to either side of the delta with river traffic routed through an intercoastal waterway that should be designed to require little or no dredging to keep clear. Incorporate the expected rise in sea levels when planning that route as well.
Supporting oil platforms at sea does not require a port in the delta. In fact, keeping the oil industry out of the delta would help keep these wetlands cleaner and my productive.
Minimize construction in the area including massive and costly government projects that would just try to make the delta into our own idea of what it should be like.
Just my 2 cents.
Thats almost exactly what I was just thinking, 2 more cents
Reply | Report Abuse | Link to thisIf we can get the Federal government to stop backing flood insurance, so that people have to pay the real cost of insuring their homes and property when they choose to live in such areas, then the economics of the situation would solve some of this by itself.
Reply | Report Abuse | Link to thisAll over our country, people are building more and more homes in areas we know are unsustainable, and they are shielded from considering the true costs of these decisions... so let's stop shielding the true costs. While it won't solve everything, it certainly can help reverse a downward dynamic...
Wishing you all good luck in this endevour.
Reply | Report Abuse | Link to thisThe predicted asteroid will alter the planet at a continental level. It may be time to give up. One prediction I saw was a Gulf of Mexico reaching Chicago.
Reply | Report Abuse | Link to thisI live on the River Ridge in the French Quarter, New Orleans. This is the land that the French originally settled over 300 years ago, and it never floods. Nonetheless, I am required to carry flood insurance on my property here that is similar to what I pay in more vulnerable parts of the city.
Reply | Report Abuse | Link to thisWe know more now about how to restore our wetlands, which can be a lucrative project. The expansion over the last 300 years into low lying areas is not particular to New Orleans, but in fact has happened, and is happening all over the globe. The marshlands on which 80% of the city is built are not crucial to food production, and not particularly fertile in their current state. The Port of New Orleans is a valuable asset that requires a physical, human resource, and financial infrastructure which the surrounding municipalities provide. All of us who live in flood zones are required to carry insurance commensurate with the value of, and potential flood damage to, the property in question. Federal agencies help establish these guidelines. The Federal guarantee is
required because insurance companies, when left to their own devices, will collect premiums but avoid payouts on claims, because they are parasitic mercenaries. If Bush didn't cut revenues while substantially increasing spending, we would have the funds necessary to be a civil society which maintains its infrastructure, rather than a banana republic which allows its levies, roads and sidewalks to crumble.
New Orleans is a vibrant and unique American cultural jewel. The metro area is home to 1.2 million people.