Sunday, August 06, 2017

In Race Against Rising Seas, Louisiana Scrambles to Save Dwindling Coast

In the absence of broad federal support, state managers in Louisiana have had to go it alone in the quest to save the state's eroding coastline.

Managed retreat--planting marsh grass (Credit: Ann Hermes/Staff | Caption) Click to Enlarge.
Tough decisions are coming thicker and faster than the Gulf of Mexico in southern Louisiana these days – and the water is coming up faster than anyone in the region can remember.  Stand on the main road in Jean Lafitte, for example, and you can smell the Gulf's salt in the air.

Faced with a multipronged assault of environmental changes combining to wash away the state’s coastline at an unprecedented rate, state officials and local communities are absorbed in nothing less than an existential struggle against an increasingly hostile and proximate ocean.

“The very basic recognition that the coast is in deep trouble and we really need to take action, that’s very widely recognized” in the state, says Torbjörn Törnqvist, chair of the Department of Earth and Environmental Sciences at Tulane University in New Orleans.

Indeed, the science has become hard for Louisiana officials to ignore.  The state is losing about a football field of land every hour due to a combination of subsidence, or gradual sinking of land; sea level rise; and a century of human development including levee building and oil and gas exploration that has disrupted the Mississippi Delta’s natural marshland-building processes.  The land loss is leaving coastal communities increasingly exposed to storms and flooding events, which are predicted to become even stronger in the future due to climate change.

Louisiana is not the only state facing these issues – Alaska and Virginia, to name two, have their own challenges – but in the absence of broad federal support the Bayou State is arguably making the most concerted effort to deal with them.

The state is 10 years into an ambitious 50-year, $50 billion (and rising) master plan to protect and restore its coastline.  The plan, which is reviewed every five years, analyzes the latest scientific research to predict how the coastline may change over the next five decades, then recommends various projects across the state to help protect and mitigate the effects of the changes.

In the most recent iteration of the plan, the best-case estimate for sea level rise almost matches the worst-case estimate for sea level rise in the 2012 plan.  It also describes as many as 200 projects in development – including levee construction, barrier island restoration, and diversion of freshwater sediment to gradually rebuild eroding marshland.

But if anything, all the activity has only created more short-term problems and unlocked tougher debates, such as how communities should respond, where money can be scraped from, and where the money should go.

Read more at In Race Against Rising Seas, Louisiana Scrambles to Save Dwindling Coast

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