Too little, too late
The arrival of a tipping point in the coast's demise has long been predicted.
As early as the 1970s, researchers had documented the scope of the state's coastal land loss. They knew the causes: a combination of levee construction, which prevented rivers from rebuilding deltas, and the thousands of canals dredged across the fragile wetlands, primarily at the behest of oil, gas and shipping.
Although the erosion imperiled the entire coast, it especially threatened the wetlands around New Orleans, where loss rates in the 1970s soared above 50 square miles per year. Whole sections of the Terrebonne and Barataria estuaries south and west of New Orleans and the Lake Borgne-Breton Sound area to the east of the city rapidly washed out to sea.
Despite that knowledge, the state did not officially commit to coastal restoration until 1989, with the creation of a trust fund to pay for projects. But during the next 15 years, most proposals were stifled by lack of financing and the conflicting concerns of competing wetland user groups such as commercial fishers and oyster harvesters, the oil and gas industry, property owners and developers.
Since the 1970s, scientists at state and federal agencies have supported a parade of legislation they hoped would finance various plans for a goal collectively known as "coastal restoration." Yet they knew the projects they advocated -- usually unsuccessfully -- would not actually stop the loss.
That includes even the massive $14 billion Louisiana Coastal Area Plan developed by the state and the Army Corps of Engineers five years ago.
Coastal advocates were appalled when the Bush administration promised only $1.9 billion to start the program two years ago. Yet St. Pe and others involved in developing the plan now concede that even if the state got the $14 billion tomorrow, the cumulative impact would not come close to building wetlands at a rate faster than they are being lost. "Everyone who has been involved in this has known for 20 years the projects we were involved in wouldn't reverse this trend," St. Pe said. "But you didn't want to speak out because you were committed at least to getting your idea -- something -- done."
Katrina has sparked an outbreak of frank urgency among scientists. "I'm concerned we've built a level of expectation of restoration among residents in many vulnerable communities that is simply not warranted by what we can deliver," said Twilley, who anticipates the state soon will have to give up on restoring the marshes protecting many communities. "People have a right to know that," he said.
Years of inaction
By the time Katrina struck in 2005, the few meager state and federal restoration efforts that escaped political purgatory had not only failed to reverse land loss, they didn't even slow it down. The impact of the big storm may finally have galvanized public opinion, but those years of inaction have taken a toll that could prove fatal to the hopes of rebuilding critical basins near the city, experts now say.
For nearly 30 years, those hopes depended on moving sediment from the rivers into the remains of the wetlands infrastructure, what UNO coastal scientist Denise Reed calls "the skeleton" of the system that once stretched from the city south to Grand Isle.
The skeleton included the natural levee ridges of ancient bayous, barrier islands, reefs and large marsh islands, all of which could trap and hold sediment and create a foundation for land growth. Even submerged, those "bones" would have provided critical help. But as the decades passed without action, many of those bones have been eroded by the relentless pounding of waves and the subsidence of the delta. Bays that once could trap sediment now are just open bodies of water, growing larger and deeper by the year. In 10 more years, experts said, the size of many bays might require an amount of fill that would be difficult to finance. "Sure, with enough money, you could build projects large enough to build land in that environment, but that isn't likely to be forthcoming," said Donald Boesch, a New Orleans native and expert on the state's estuaries who serves as president of the University of Maryland Center for Environmental Science. "That's why I say we have 10 years left to get this done," he said, echoing St. Pe and others.
Losing Barataria basins
No area is more imperiled than the wetlands of the Barataria-Terrebonne basins, directly south of New Orleans -- the weakest link in the metro area's hurricane defense.
While engineers say they can protect the city's northern flank by controlling storm surge into Lake Pontchartrain with floodgates or other barriers across key passes, no such option exists to the south. The Barataria estuary is simply too large. It stretches in a wide arc along the Mississippi River's west bank, from the freshwater marshes behind Marrero and Westwego, south past Lafitte to Grand Isle, including Belle Chasse, Port Sulphur, Empire and Venice near the mouth of the Mississippi.
Before 1940, Barataria was a trusted storm-fighter, an almost solid mass of cypress swamp, marsh, barrier islands and ridges providing nearly 80 miles of hurricane buffer between the city and the open Gulf.
Since then, the Barataria basins have suffered the greatest rates of land loss in the state. Maps of the region are filled with names of communities that no longer exist, and once-vast marsh islands that are now open water.
Anglers like Joe Courcelle of Jesuit Bend routinely find themselves operating their fishing boats over spots their charts show as solid land. "We're always fishing 'used-to-bes,' " he said. "This used to be Bird Island. This used to be Manila Village."
The quickening pace of erosion has been impossible to ignore for some scientists involved in the fight, because it has literally reached their office doors. Any strong southerly wind now floods roads and yards in communities such as Montegut and Cocodrie along Louisiana 56 in Terrebonne Parish -- little more than 35 miles from the French Quarter.
That has forced researchers at the Louisiana University Marine Consortium in Cocodrie to take boats to work, and the erosion has made life ever more precarious in communities once separated from the Gulf by miles of marsh. "We can't plant gardens anymore because when we get a south wind, the tide comes out of the bayou and covers the yards and the roads," said Carolyn Johnson, who has lived in Cocodrie for 30 years. "We used to only see that with hurricanes."
Such tidal inundation has become a fact of life for almost every community outside hurricane protection levees south and west of the city. The imperiled wetlands to the east offer only slightly more protection to St. Bernard and Plaquemines parishes. Although the land base there better resists erosion, projects such as the Mississippi River-Gulf Outlet shipping channel have weakened that buffer and exposed large developed areas to floods. "The enemy is at the gates," said Jimmy Johnston, who recently retired as chief of the spatial analysis branch of the U.S. Geological Service National Wetlands Research Center, which uses maps and satellite photos to track changes in landscape. "The Barataria estuary is just a disaster. Anyone who thinks we've got 10 years left over there is dreaming."
Aggressive advance
Since scientists first addressed the problem in the 1970s, they have stressed the need for quick action because of the aggressiveness of the sea's inland advance.
As the amount of open water grows, winds build larger waves that strike shorelines with greater force, increasing the rate of erosion. And that results in exponential acceleration: The larger the problem gets, the faster it gets even larger.
St. Pe uses a brief animation that graphically depicts the calamity now unfolding south of the city. Marshes that appear solid in the early 1900s are pocked with holes that slowly grow larger until the 1990s, when the pace dramatically speeds up. By 2020, the expanse of open water is almost unbroken from Lafitte to Grand Isle, Venice to Golden Meadow. "That's where we are right now," St. Pe said of the last 10 seconds in the animation. "We had opportunities in the 1980s to really stop this, to get ahead of the curve. And people still don't seem to realize this isn't something we can wait on. While we were arguing over what to do, the process was gaining speed."
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Bob Marshall can be reached at bmarshall@timespicayune.com or (504) 826-3539.
Staff writers Mark Schleifstein and Matthew Brown contributed to this article.
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