A Decade After Katrina, Can We Win Over Rising Oceans?

For a casual observer enjoying a classic New Orleans second line parade, it might be hard to imagine the damage wrought by Hurricane Katrina. Ten years ago, a massive, nearly 20-foot storm surge breached the city’s levee walls, damaging or destroying over a million homes and businesses and taking over 1,800 lives. 

(Photo credit: Ron Reiring)

But New Orleans has always been a town of rebirth. After the storm exposed the city’s vast racial and economic divides – with lower-income and African American residents more likely to have gone without food and water, spent time in overcrowded and underprepared emergency shelters, and even lost their lives in the disaster – it now serves as prime evidence of the need for climate justice the world over. We know that natural disasters affect everyone, but they don’t affect everyone equally. Indeed, it is communities of low-income and minority residents that often take the biggest hit when Mother Nature turns on us.

As residents commemorate the 10th anniversary of the storm, it’s worth considering if the efforts to gird Crescent City from another big one are taking into account the biggest one of all: climate change.

Climate Change: The Next Big One

Over $14.5 billion has been spent to protect New Orleans from hurricanes and storm surges since Katrina. A system of levees, pump stations and a network of sea walls — the largest structure ever built by the Army Corps of Engineers— everything the city needs to withstand a storm of Katrina’s category. Experts agree that’s a win for the city, but what about rising sea levels?

The International Panel on Climate Change is already warning of up 3 feet of sea level rise by 2100. Now, prominent scientists like James Hansen argue that with the rate our polar ice is melting, we could expect to see that amount double or triple. That’s going to cause major trouble for coastal cities around the world. The rub for New Orleans is that despite multi-billion dollar flood defenses, the natural barriers which could buffer New Orleans from sea level rises— and hurricane flooding— have largely been thrown out with the proverbial bathwater.

The Delta Blues

Before New Orleans was the bustling city we know today, the rich sediment carried south by the Mississippi River created the delta of marshes and wetlands between the city and the Gulf of Mexico. Flooding was a regular and natural occurrence in this eco system, but when settlers wanted to farm the land, they hemmed in the Mississippi.

The development of the city, a need for consistent and reliable shipping routes, and expansion of oil interests in the delta have seen the river piped straight to the sea. Cut off from the sediment flow, the wetlands that buffer New Orleans from the ocean have been decimated. From 1932 to 2010, Louisiana lost 1,900 square miles worth of wetlands, nearly the same size as the entire state of Delaware. At that rate, Louisiana is currently loosing wetlands at a football field size an hour.

(Photo credit: Alicia Lee)

Natural Protections

Over a decade ago, researchers began a small project to see if opening channels from the Mississippi into the wetlands— sediment diversions— could successfully carry natural river sediment to build up the wetlands delta. The project is considered a success, and sediment diversion is included in a $50 billion state coastal master plan— that’s mostly been hamstrung by lack of funding and bureaucratic red tape.

For the past ten years, wetlands restoration has been a backburner project compared to hurricane protections. But now that Louisiana’s portion of the $18.7 billion BP Deepwater Horizon settlement is set to flow in, the plan is expected to see more implementation. Sediment diversion is not without risk, or cost. As more freshwater flows into the wetlands, saltwater species that the local fishing industry depends on will be pushed out into the gulf. Of course, the other side of the coin is that if you don’t adapt to climate change, there won’t be any industry, of any sort, remaining.

Lessons learned in the Big Easy are impacting coastal regions across the nation: nature’s barriers, if left intact, usually work better than any we can build. Ten years after Hurricane Katrina, New Orleans remains a laboratory of sorts, where the state of Louisiana, and the nation, work out what we need to do— and what we’re willing to sacrifice in the short term— to secure a future where we’re not all the way underwater.