After Hurricane Katrina, the Louisiana congressional delegation asked John Barry to chair a bipartisan working group on flood control. In 2006 the National Academy of Sciences invited him to give the 2006 Abel Wolman Distinguished Lecture on Water Resources-- he is the only non-scientist ever to give that lecture. In 2007 he was appointed to the Southeast Louisiana Flood Protection Authority, which oversees several levee districts in the metropolitan New Orleans area, and the Louisiana Coastal Protection and Restoration Authority, which is responsible both for the state's hurricane protection and for rebuilding the 2100 square miles of land the state has lost in recent decades. He has discussed Katrina and its aftermath in such venues as Meet the Press, NPR, and the BBC, and he has written about it for The New York Times, Time Magazine, USA Today, The Washington Post, and The Smithsonian.
The essay below combines information that appeared originally in different articles in The Washington Post, The New York Times, Los Angeles Times, and Time Magazine. It was updated in April 2011.
Protecting Louisiana is not a partisan issue. It's a leadership issue. John Barry is a liberal Democrat. Newt Gingrich is a conservative Republican. Yet Barry and Gingrich co-authored an essay in Time making many of the points below.
Five of the fifteen largest ports in the U.S. are in Louisiana. 20% of all waterborne commerce moving on U.S. waters moves through Louisiana. 30% of all domestic oil and gas production is produced in or off-shore Louisiana, and a comparable percentage of the nation's refining capacity is in the state. By weight, 40% of all commercial fish caught in the U.S. is caught in Louisiana waters. All of this economic activity-- activity upon which the entire nation depends-- has become increasingly threatened by hurricanes because of the erosion of nearly 2,300 square miles of coastal land, marsh, and barrier islands.
The land loss has made the region far more vulnerable to hurricanes than nature made it. Each land mile over which a hurricane travels absorbs between six inches and a foot of storm surge, so the loss of this buffer has had enormous impact. Here's another way of putting it: the land lost is roughly equivalent to the state of Delaware. If you wrap the state of Delaware around New Orleans, it wouldn't need levees. Protecting the region requires restoration of this buffer.
Much of the debate since Katrina has been conducted without any real understanding of the geological context. To engage in intelligent debate, Washington needs to recognize the following geological facts, facts which are not in dispute, and which address the key question: how did the land-loss occur and what can be done about it?
- Fact 1: The task is absolutely urgent. Currently one football field-size chunk of Louisiana's land melts into the ocean every 50 minutes. The scientific community believes that aggressive action must be taken within a few years, certainly within a decade, or we will reach a tipping point and it will be too late.
- Fact 2: The Gulf of Mexico once reached north to Cape Girardeau, Mo. But the Mississippi River carried such an enormous sediment load that, combined with a falling sea level, it deposited enough sediment to create 35,000 square miles of land from Cape Girardeau to the present mouth of the river. Then ocean currents carried sediment from the mouth of the river east and-- mostly-- west to build more land.
This river-created land, a total of approximately 40,000 square miles, includes all of the Gulf Coast and barrier islands stretching from western Mississippi to Texas. But human interventions have interfered with this natural process and have dramatically increased the hurricane threat to the Gulf Coast. These interventions benefit the rest of the country while increasing the danger to Louisiana and Mississippi.
- Fact 3: The Mississippi River historic natural sediment load-- the sediment that built the land-- was once 400 million tons a year. It has now declined to about 125 million tons a year. This decline of sediment in the river is a major factor in land loss.
The decline occurred for several reasons, but more than half the total sediment decline is caused by a series of six dams on the upper Missouri River. These dams, in Montana and North and South Dakota, were built to produce hydro-electric power and provide irrigation and, ironically, flood protection in the region. The reservoirs created by the dams are so huge they have a coastline longer than California's. And according to the U.S. Geological Survey, once these dams were built the flow of sediment from this area "virtually stopped." The dams now retain about 150 million tons of sediment a year-- more sediment is kept back by these dams than the entire rest of the Mississippi River system now delivers to the Gulf.
But the dams are not the only cause of sediment decline. Acres of riverbank at a time used to collapse into the river system providing a main source of sediment. To prevent this and to protect lives and property, engineers stopped such collapses by paving hundreds of miles of the river with riprap and even concrete, beginning more than 1,500 miles upriver -- including on the Ohio, Missouri and other tributaries -- from New Orleans. The loss of all this sediment has starved the coast.
Thus, producing electricity on the High Plains, encouraging economic development in much of the country, and making these areas safer has actually-- and quite directly-- increased the danger to Louisiana.
- Fact 4: To stop sandbars from blocking shipping at the mouth of the Mississippi, engineers built jetties extending more than two miles out into the Gulf of Mexico, dropping most of the sediment remaining in the river into deep water off the continental shelf. So even the sediment in the river is largely wasted, and is prevented from replenishing the Louisiana and Mississippi coasts and barrier islands.
These jetties benefit the national economy. For example, they make Tulsa, Kansas City, Cincinnati, Pittsburgh and other cities into ports with direct access to the ocean, greatly enhancing the nation's economy. The river carries 20 percent of the nation's exports, including 60 percent of its grain exports, and the river at New Orleans is the busiest port in the world.
The downside, though, is that-- as with the decline of sediment-- the national benefits of the jetties have directly increased the danger to Louisiana and parts of Mississippi.
- Fact 5: Similarly, the Gulf Intra-coastal Waterway, which was originally built for national security, to protect shipping from German submarines, runs from Texas to Florida (indeed, it crosses Florida to connect with the Atlantic Ocean at Jacksonville). But the GIWW and many other shipping channels have allowed salt water intrusion into coastal marsh, enormously accelerating its erosion.
The GIWW does benefit the port of New Orleans, but it also benefits the ports of Houston, Gulfport, Biloxi, Mobile, Jacksonville, and others.
- Fact 6: Levees that prevent river flooding in Louisiana and Mississippi interfere with the replenishment of the land locally as well. This contributes to subsidence of the land. The levees causing the greatest land loss are well down river from populated areas, and they were not built to protect people-- much of the area is entirely unpopulated. The levees in this region were built to help control the shipping channel, and thus benefit interstate and international commerce. Again, the benefits to the national economy have increased the danger to Louisiana.
- Fact 7: Roughly 30 percent of the country's domestic oil and gas production comes from offshore Louisiana, and to service that production the industry dredged more than 10,000 miles of canals and pipelines through the marsh.
Every inch of those 10,000-plus miles lets salt water penetrate, and eat away at, the coast. Scientists dispute precisely how much of the land loss was caused by the oil and gas industry-- some believe well over half the damage is directly attributable to it-- but no one, including industry scientists, disputes that this industry is responsible for a significant share of the damage.
So energy production has enormously accelerated what was a slow degradation, transforming a long-term problem into an immediate crisis. A good analogy is that the loss of sediment is akin to moving a block of ice from the freezer to the sink, where it begins to melt; the effect of the canals and pipelines is like attacking that ice with an ice pick, breaking it up.
Fact 8: The region can, literally, rise above a rising sea level. The delta of the Mississippi River is a dynamic, living system. This means that, if supplied with sediment, the region can adjust to and rise with the consensus predictions for rising sea level.
The nation as a whole gets nearly all the benefits of engineering the river. Louisiana and parts of coastal Mississippi get 100 percent of the costs. Those costs include vastly increased vulnerability to hurricanes.
Nothing better exemplifies this allocation of benefits and costs than eastern New Orleans, including the lower Ninth Ward, and St. Bernard Parish (nearly all the occupied areas of which, incidentally, are at or above sea level). Three man-made shipping canals-- the Industrial Canal, the Gulf Intra-coastal Waterway, and the Mississippi River Gulf Outlet-- pass through this part of the metropolitan area. These shipping channels create almost no jobs in eastern New Orleans or St. Bernard, but benefit commerce throughout the country. Yet 175,000 people living in this area saw their homes flooded or destroyed, in most cases not because of any natural vulnerability but because of levee breaks on each of these man-made canals.
Without action, land loss will continue, and it will increasingly jeopardize populated areas, the port system and energy production. This would be catastrophic for America. Again, scientists warn that we have only a decade to begin addressing it in a serious way or we will pass a tipping point and the damage will become irreversible.
Generating benefits to the nation is what created the problem, and the nation needs to solve it. Put simply: Why should a cab driver in Pittsburgh or Tulsa pay to fix Louisiana's coast? Because that cab driver gets a stronger economy and lower energy costs from it-- after Katrina gas prices spiked more than $1 a gallon-- and because those benefits created the problem. The failure of Washington to act aggressively to repair the coastline at the mouth of the Mississippi River could threaten the economic vitality of the nation.
The state of Louisiana itself has committed enormous resources to the problem. Three years ago Louisiana voters approved a constitutional amendment dedicating 100% of state revenue flowing from oil and gas production off the outer continental shelf to coastal restoration and flood protection. The U.S. Congress has to all practical purposes limited this money to no more than $300 million a year, even though such states as New Mexico, Wyoming, and Colorado get many times that from revenues derived from federal land. (The justification for giving states money from federal property is to reimburse them for environmental damage and infrastructure development, but obviously none of them have anything like the environmental damage Louisiana suffers.) But no appreciable money starts flowing until 2017. We need action now.
Right now, the state has upwards of $6 billion in restoration and protection projects within two years of turning a shovel. Yet the Obama administration has proposed, by the most generous count, less than $50 million for these projects.
To its credit, the Obama administration has also been developing an inter-agency approach to greatly accelerate the whole process of building levees and restoration projects. How well that works remains to be seen, but at the moment there is reason for some optimism.