Once Gone, Gone Forever
Louisiana’s Continuing Crisis of Land Loss

The crisis of land loss in coastal Louisiana is plain to see, according to Windell Curole, general manager of the South Lafourche Levee District. “Even over a few weeks’ time you can see changes in the landscape,” he says. “You’d have to try hard not to notice the problem.”

As an example, he points to the Leeville bridge. It wasn’t so long ago, according to Curole, that you’d only get a glimpse or two of the bridge on the way down to Grand Isle. “Now the landscape’s flattening out,” Curole says. “Ridges are gone. Trees have disappeared. You can see the bridge almost the whole way.”

The rate at which Louisiana’s land is converting to water is probably the fastest in the world. Since 1932 the state has lost an estimated 1,900 square miles of coastal land, an area about the size of the state of Delaware, or acreage equivalent to 80 Manhattans. According to the most recent study, the state will lose between 500 and 700 more square miles within the next 50 years, numbers that will swiftly increase should sea levels rise, subsidence rates expand, or accretion diminish. Ninety percent of the lower 48 states’ coastal marsh loss occurs in Louisiana, an increase of 10 percent over the past two decades. Consequently, Louisiana’s share of the nation’s coastal marshes has declined from 40 percent in the 1980s to 30 percent today.

That the rate of land loss has fallen from its peak of 39 square miles a year during the 1970s actually indicates how severe the crisis is. “You can’t lose the same land twice,” Denise Reed, professor of geology at the University of New Orleans, points out. “We’re losing less land because there is less land to lose.”

Report Measures Loss, Past and Future

To appraise the crisis of land loss in Louisiana, the Louisiana Coastal Area Comprehensive Coastwide Ecosystem Restoration Study and the Louisiana Coastal Wetlands Conservation and Restoration Task Force commissioned a team of scientists to produce the report Historical and Predicted Coastal Louisiana Land Changes: 1978 – 2050. Analyzing aerial photographs and satellite imagery, the team calculated past loss and predicted probable future loss for the next 50 years. The document substantiates the severity of the crisis of Louisiana’s vanishing wetlands.

Generally scientists agree that it takes centuries to reverse land loss and that the next several decades will produce little land accretion to offset Louisiana’s decline. However, by describing the patterns across the coast where land loss does, or does not, occur; by determining the locations at greatest risk; and by disclosing where there is stable marsh to build on, the report assists planners in designing remedies.

“Two things make a difference,” says Denise Reed, “land preservation and land creation. To some degree, we can accomplish both.”

Coastal Projects Effect Changes

Land preservation and land creation have been the primary goals of the Louisiana Coastal Wetlands Conservation and Restoration Task Force since it was established in 1990. The task force, composed of five federal agencies and the state of Louisiana, implements the Coastal Wetlands Planning, Protection and Restoration Act (CWPPRA), or, as it is also known, the Breaux Act. Although land loss from erosion and subsidence is a natural phenomenon, as is land accretion from sedimentation and vegetative growth, human intervention in Louisiana’s landscape is decidedly a major factor in land change. For example, hundreds and hundreds of miles of pipeline canals increase erosion in the marshes of Terrebonne Bay. On the other hand, outflow projects that direct waterborne sediments over the Atchafalaya River delta are causing significant land accretion.

Over its 13-year history, the task force has accumulated valuable experience both in techniques for wetlands restoration and in working together with other concerned parties outside of government to address the crisis. The report Historical and Predicted Coastal Louisiana Land Changes: 1978 – 2050 gives the team the scientific data needed to shape effective measures to combat land loss and demonstrate why the dire condition of Louisiana’s coastal wetlands is a crisis of national concern.