Twenty years after Katrina, study finds that Louisiana's flood defenses cut expected damages by 60%
Twenty years after Katrina, study finds that Louisiana's flood defenses cut expected damages by 60%
| Author: | Brenna Losch |
|---|
As the nation reflects on the 20th anniversary of Hurricane Katrina, Ravi and Eleanor Talwar Rising Star Associate Professor Edwardson School of Industrial Engineering, Dr. David Johnson, sheds light on the progress made in protecting Louisiana's communities from devastating storms.
In collaboration with The Water Institute of the Gulf and the Louisiana Coastal Protection and Restoration Authority (CPRA), Dr. Johnson co-authored a new study quantifying the impact of Louisiana’s two decades of investment in flood risk reduction and coastal restoration. Last week, he presented the findings to nearly 90 members of the U.S. Army Corps of Engineers.
The results are striking. According to the analysis, Louisiana’s post-Katrina investments in risk reduction are delivering returns on investment ranging from 4:1 to 10:1. “The investments made since 2005 are reducing risk and paying for themselves many times over,” the study concludes. The upgraded system reduces expected annual damages by $6-8 billion annually.
The report compared Louisiana’s current levee and coastal systems with a “no investment” scenario, simulating what would have occurred if no improvements had been made after 2005. The findings show that statewide expected flood damages are nearly 60% lower today.
At the center of these investments is the Greater New Orleans Hurricane and Storm Damage Risk Reduction System (HSDRRS): an $18 billion network of levees, gates, and pumps completed in 2018. It is just one of many coastal restoration projects that Louisiana has implemented since Hurricane Katrina. Dr. Johnson's analysis shows that during Hurricane Isaac in 2012, the nearly complete system prevented up to $165 billion in damages, more than paying for itself in a single storm.
A boat passes through the Chef Menteur Pass Bridge, with New Orleans in the distant background. (Photo via Jabriel/Pexels.com)
Louisiana’s coastal protection efforts extend well beyond New Orleans. An additional $3 billion in levee upgrades, new risk reduction systems, and ecosystem restoration projects have dramatically lowered flood risk across parishes such as Plaquemines, Lafourche, and Terrebonne. Statewide, these projects have cut expected annual flood damages by 60%, with benefit-cost ratios as high as 8-to-1.
“This study shows what’s possible when science, leadership, and sustained commitment come together,” said Beaux Jones, President and CEO of The Water Institute, in CPRA’s announcement.
Dr. Johnson’s work spotlights the vital role that industrial engineering methods, such as risk modeling, cost-benefit analysis, and systems optimization, play in addressing some of society’s most pressing challenges. His research demonstrates the critical impact of engineering beyond the factory floor, contributing directly to safer, more resilient communities.
The work of Dr. Johnson’s Environmental Decision-Making Lab highlights the vital role engineers play in solving society’s most complex problems. By combining operations research, risk modeling, and cost-benefit analysis, their research aids the government of Louisiana in making informed investments that save lives, protect communities, and strengthen resilience.
Author: Brenna Losch