Louisiana's draft coastal master plan update promises billions in hurricane-damage savings

A draft update of the state's $50 billion coastal master plan predicts that 61 new projects to build or protect land, a dozen new levees, and new efforts to elevate, flood-proof or relocate flood-prone homes will reduce annual hurricane storm surge damages by at least $11 billion per year by 2073.

The plan includes calls for construction of projects long proposed to reduce flooding risk, such as a $2.4 billion concrete barrier and weir combination aimed at reducing surge entering Lake Pontchartrain through the Rigolets and Chef Menteur passes.

It also reverses some past decisions to not build major levees, including plans to protect portions of Iberia and St. Mary parishes from Gulf of Mexico surge; to dramatically upgrade levees surrounding the Lafitte area , and to protect portions of St. James and Ascension parishes, where sea level rise is expected to increase the threat of flooding from Lake Maurepas over the next 50 years.

The $1.7 billion, 31-mille Iberia-St. Mary Upland Levee would be designed to withstand surges caused by a hurricane with a 1% chance of occurring in any year – a so-called 100-year storm – and would be built during the plan's first 20 years. The project will reduce surge flooding for New Iberia, Jeanerette, Lydia and the Port of Iberia.

Both the $1.4 billion, 28-mile Lafitte Ring Levee, which would be raised from its present 7 ½-foot level to a 16-foot, 100-year-flood level, and the $730 million, 39-mile St. James-Ascension Parishes Storm Surge Protection levee project would be built during the plan's final 30 years.

Most money set aside for coastal restoration will be dedicated to projects that dredge sediment from the Mississippi and Atchafalaya rivers or from local bays, with $16 billion set aside for marsh restoration, and $2.9 billion for land bridges – combinations of wetlands, ridges and above-water land – to be built across stretches of open water in the Barataria and Lafourche basins.

The 100-page report, released Friday by the state Coastal Protection and Restoration Authority, is focused on offsetting at least some of coastal erosion caused by natural subsidence and global warming's effect on sea levels, while also reducing the risk of damage from flooding for the state's 2 million coastal residents.

Stuart Brown, who oversees the master plan program for the CPRA, said the loss of nearly 2,000 square miles of coastal land since 1932 has directly impacted coastal fisheries and wildlife resources and the jobs and incomes that depend on them.

"We have been experiencing a land-loss crisis for nearly a century," he said.

The land losses directly impact other segments of the coast's economy and culture, too, including agriculture, tourism, the navigation industry, and oil and gas, he said.

"And, of course, land loss also increases the flooding impacts of hurricanes and tropical storms," Brown said. "And this is likely how most coastal citizens most acutely experience the impacts of land loss."

"Addressing Louisiana's land loss crisis and protecting coastal communities requires the comprehensive and integrated approach that projects identified in the master plan offer," added CPRA Chairman Chip Kline. "No other state in the country has a plan like ours utilizing the best available science and engineering to preserve our coast and culture for generations to come."

The update is the fourth to the master plan since it was first adopted by the Legislature in 2007. All three of the previous plans received unanimous approvals of the Legislature. In 2018, lawmakers voted to lengthen the time between rewrites from five to six years, meaning the next revision will be in 2029.

Public comments on the plan will be collected by the CPRA through March 25. The draft will be reviewed by the authority's board on Jan. 18, and four public hearings at different locations across the state will be held from Jan. 31 to Feb. 16. The CPRA board will vote on the revised plan, incorporating comments, on April 19. It will be submitted to the Legislature on April 24.

Brown and other state officials have stressed that Louisiana will continue to lose a significant portion of its wetlands over the next 50 years, even if all the projects in the plan are added to the billions of dollars already spent on restoration and hurricane protection since 2007. The risk of damage from hurricane storm surge and other flooding will also continue to increase, though the plan is expected to reduce that damage considerably.

Public officials, representatives of industry, community groups and environmental organizations that have participated in briefings or served on advisory teams say delays in the plan's approval and implementation are not an option.

"We have some tremendous, tremendous challenges facing Louisiana environmentally, moving forward, even with plans like this that are complex and multifaceted," said Simone Maloz, campaign director with Restore the Mississippi River Delta, an organization supporting Louisiana's coastal restoration efforts that includes representatives of numerous environmental advocacy groups.

"It really represents our best shot at a sustainable future here in Louisiana," said Simone Maloz, campaign director with Restore the Mississippi River Delta, an organization supporting Louisiana's coastal restoration efforts that includes representatives of numerous environmental advocacy groups.

And Alex Kolker, a coastal researcher with the Louisiana Universities Marine Consortium, warned that the new plan's estimates of land saved over the next 50 years -- only between 230 and 310 square miles -- is already dramatically less than a similar estimate in the 2017 version of the plan, which predicted 802 square miles would be built or maintained through its 50-year period ending in 2067.

He blamed the expected drop on increased rates of sea level rise driven by global warming and the effects of subsidence.

"The more we can do globally to reduce the impacts of climate change, the more options Louisiana will have available to restore the coast," Kolker said.

The plan aims to improve flood protection, restore the flow of water or introduction of sediment along the coast, protect coastal habitats, protect the state's cultural heritage and assuring that Louisiana maintains its unique "working coast," where residents' jobs are more likely to depend on the value of the coast's resources, not just tourism.

While the plan estimates costs for projects, its approval does not trigger the appropriation of money for individual projects. Many of its projects will likely be paid for with a combination of federal, state and local sources.

In recent years, the state has often managed to capture $1 billion a year or more to pay for coastal projects, including more than $2.6 billion in federal funds in 2021, but the plan notes that such funding is not assured.

For instance, state officials are using portions of more than $10 billion from various settlements with BP over the 2010 Deepwater Horizon oil spill, but those funds are expected to run out around 2032.

The state also expects to get an increasing share of offshore oil revenue under the federal Gulf of Mexico Energy Security Act, which gives the state and coastal parishes 37.5% of offshore revenue from recent oil and gas production in federal waters. The state has dedicated most of its share of GOMESA money to various levee and other infrastructure projects aimed at reducing coastal flooding.

An attempt to remove a cap on how much Louisiana and other Gulf states receive under GOMESA never made it out of Congress at the end of last year, but similar legislation is expected this year.

The cap provision now limits total funds going to Louisiana, Mississippi, Alabama and Texas to $500 million a year. Louisiana only received about $112 million from the program in 2022.

The state also has been eyeing various pots of federal money made available through the Inflation Reduction Act and the Infrastructure Investment and Jobs Act for project funding, as well as through funding streams like the Army Corps of Engineers' annual budget.

The state also funds projects through its annual budget process.

In designing individual projects and determining which ones to pursue, the plan uses two future scenarios to estimate the effects of sea-level rise. Those scenarios also include lower and higher estimates of hurricane intensity, precipitation and other factors over the plan's 50-year lifetime.

The lower scenario predicts 1.6 feet over 50 years; the higher scenario predicts 2.5 feet. Subsidence and other factors were added.

Under the lower scenario, if none of the plan's projects are adopted, Louisiana's coastline would lose another 1,100 square miles of land by 2070, and flood damages could rise to $15 billion a year. Under the more pessimistic scenario, as much as 3,000 square miles of land could be lost, and annual damages coastwide could rise to $24 billion.

Both of those estimates reflect new protection added by projects built since the 2017 plan was approved, and expected improvements resulting from projects to be completed in the next few years. That includes the land expected to be added by the Mid-Barataria and Mid-Breton sediment diversions, and flooding reductions resulting from the West Shore Lake Pontchartrain hurricane levee.

If all of the new plan's projects are built, annual flood damages using the lower scenario would be cut by $11 billion; damages under the higher scenario would be cut by $15 billion.

Officials also estimate that under the lower scenario, 314 square miles of land will be created and maintained at the end of 50 years, and 233 square miles would be added under the higher scenario. That means even if all the projects are built, significant land loss will still occur across the coast, with 786 square miles still lost by 2070 under the lower scenario and 2,767 square miles still lost under the higher scenario.

Public hearings on the plan are scheduled for Jan. 31 at the East Baton Rouge Parish Library, 9200 Bluebonnet Blvd., in Baton Rouge; Feb. 2 at the Houma Municipal Auditorium, 800 Verret St., Houma; Feb. 7 at the University of New Orleans, 2000 Lakeshore Dr., in New Orleans; and Feb. 16 at Burton Coliseum Complex, 7001 Gulf Highway, Lake Charles.

Each hearing is preceded by an open house, which will begin at 3:30 p.m., followed from 5:30 p.m. to 7:30 p.m. with a presentation and public comment session. Comments can also be submitted to masterplan@la.gov, or by mail to CPRA, 150 Terrace Ave., Baton Rouge, LA 70802.

A master plan data viewer also is available online.

Draft Louisiana 2023 Coastal Master Plan