Marsh and oyster reef restoration near the now-closed Mississippi River Gulf Outlet along with improved methods of removing storm water from inside the New Orleans levee system could enhance storm-protection work already done since Hurricane Katrina, according to a new report released Tuesday.
“We’re seeing progress on a lot of fronts,” said David Muth, director of the National Wildlife Federation’s Gulf restoration program. “We have a long way to go.”
Much of the message around the 10th anniversary of Hurricane Katrina this year has been that the city is back, thriving and safer than ever, said Cynthia Sarthou, executive director of the Gulf Restoration Network.
“The truth is we’re not safer than ever. We’re safer than we were a day before Hurricane Katrina,” she said.
The wetlands outside the massive levee system haven’t been restored and without that, as well as better work to handle drainage within New Orleans, levees can still be overtopped and flooding within the city can still occur.
“Evacuation is always going to be a part of sustainability,” she said.
Sarthou said she’s heard talk about people not having to evacuate if a Category 2 storm is approaching because the levees are so much stronger. But there are limits to what levees can protect against.
“We are a coastal city more and more every day, and we really need to think like that,” she said. “There is a segment of the population who believe they don’t have to evacuate anymore.”
Shortly after hurricanes Katrina and Rita ravaged south Louisiana, the “multiple lines of defense strategy” — which calls for the rebuilding of barrier islands, coastal wetlands and forested ridges of land as well as levees and better water management inside levees — began to get traction as a way of taking some energy out of storm surge.
“Pieces of the multiple lines of defense strategy are falling into place,” Muth said.
Flying over the Lower 9th Ward this week, Muth pointed out coastal restoration work the report recommends to give additional protection to New Orleans. All are included in the state’s master plan and some are on the state’s list to possibly receive Deepwater Horizon settlement money.
Projects include the marsh creation and oyster reef restoration as well as marsh creation in an area of west St. Bernard Parish known as the Golden Triangle Marsh.
“Compared to the Barataria-Terrebonne basin, it’s eroding much more slowly,” he said. “Investment here in restoration or oyster reefs is a good long-term investment.”
Other recommendations include the need to find long-term funding to maintain and improve levee systems and to increase work on non-levee options such as raising homes and increasing building code standards.
The report also highlights the need to rethink storm water runoff within the New Orleans levee system. Instead of trying to direct water into concrete-lined channels and pumping the water out of the city, methods must be implemented to retain water in a safe way so it can be gradually released.
“Just as levees alone are not enough, just pumping (the water out) is not enough,” Sarthou said. “There needs to be an acknowledgement that we need to live with water, because we’re not going to be able to pump it all out fast enough to keep from flooding.”
The report, “10th Anniversary of Katrina: Making New Orleans a Sustainable Delta City for the Next Century,” is from the MRGO Must Go Coalition.
The report noted that in the 10 years since Hurricane Katrina, $14 billion in improvements have been done to the levee system around New Orleans and the Mississippi River Gulf Outlet, blamed for decades of marsh loss, has been closed.
The outlet, known commonly as MRGO, was widely blamed for providing straight-line access for storm surge to travel from the Gulf of Mexico to New Orleans. In the same legislation that authorized the channel to be closed in 2009, Congress authorized restoration work on wetlands the channel had harmed or destroyed in the previous decades. Congress has not authorized funding for that work as of yet.
“The new structures that have been built to block flow and storm surge in the MRGO are huge accomplishments, but the legacy of its impact on wetlands has yet to be addressed in earnest,” according to the report.
Follow Amy Wold on Twitter, @awold10.