The 2016 flooding in south Louisiana was offered as evidence of the destructive potential of climate change in a recent White House report.
The Fourth National Climate Assessment is an exhaustive review of environmental data by a team of hundreds of scientists. Its findings are grave and made clear from the first two sentences:
"Earth’s climate is now changing faster than at any point in the history of modern civilization, primarily as a result of human activities. The impacts of global climate change are already being felt in the United States and are projected to intensify in the future."
The report turns to Baton Rouge in a chapter on threats to the South. It counts the total losses from the August 2016 flood at $10.1 billion.
"Events of such magnitudes are projected to become more likely in the future due to a changing climate, putting more people in peril from future floods," the report states.
The South is somewhat unique, according to Adam Terando, a research ecologist with the U.S. Geological Survey's office in Raleigh, North Carolina. Temperatures in the region haven't risen as much as they have in the rest of the world, he said, but the South is especially susceptible to sea level rise and flooding.
Though Louisiana enjoyed a quiet hurricane season — which ended with the turn of the calendar — there was an above-average number of Atlantic storms.
Terando co-led the chapter on the Southeast with LSU climate change researcher Lynne Carter, who was unavailable for comment.
A warmer climate allows more water vapor to collect, which is already causing the more frequent and intense kinds of rain that lead to flooding, Terando said.
"That's happening now, and that's something we expect to have a big impact into the future. ... Think of it as fewer showers, more deluges," he said.
The Climate Assessment says Southerners are also at risk because they continue to rebuild in dangerous areas, partly because of out-of-date flood maps used to calculate insurance and warn people of flood risk.
"Existing flood map boundaries do not account for future flood risk due to the increasing frequency of more intense precipitation events, as well as new development that would reduce the floodplain's ability to manage storm water," the report states. "As building and rebuilding in flood-prone areas continue, the risks of the kinds of major losses seen in these events will continue to grow."
After the 2016 flood rerouted the channel of the Amite River, locals had a chance to consider whether to update the area's maps, many of which are several decades old. However, there seems to be little appetite. Mark Harrell, Livingston Parish's emergency preparedness director, said he's not in favor of a change.
The maps that dictate how much south Louisianans pay for flood insurance could be redrawn, though Baton Rouge-area leaders have their doubts.
Rather, Harrell is focusing on pooling resources with neighboring parishes to build regional flood control projects. The Climate Assessment singled out eight Acadiana parishes for doing just that. By combining their efforts — and their federal hazard mitigation money — the region is working to improve the Teche-Vermilion watershed, the report notes.
The capital region has talked about similar action, but so far, parishes haven't banded together on a single project. Harrell said he's optimistic that will happen in the future.
The Climate Assessment also discusses the National Flood Insurance Program's incentive program, which offers residents reduced premiums if their local government adopts resilient practices. It commends communities in Florida, Mississippi, Georgia and South Carolina, but none in Louisiana.
Approximately 5,000 new homes have been approved in East Baton Rouge, Ascension and Livingston parishes since the flood, but locals have clamored for changes to building requirements. East Baton Rouge has begun a review of its Unified Development Code, which will include a "wholesale rewrite" of portions dealing with stormwater management, Planning Director Frank Duke said.
The changes will include requiring open spaces on types of residential developments where those are not required and revising the rules where they are already mandated, he said. Some of that work is getting close to finishing.
The city-parish is also working with the firm developing the East Baton Rouge Storm Water Master Plan to completely refashion the rules that govern fill, stormwater plans and drainage impact studies. Those recommendations should come out mid- to late 2019, Duke said.
How has the process been?
"Painful," Duke said.
He's heard that a locality should update its code when it's older than the youngest person on the planning team. Duke's youngest is 22.
"Our code dates back to the '80s," he said.
WASHINGTON — Congress pushed back its deadline to deal with the National Flood Insurance Program by at least a week, passing yet another short…