The Federal Emergency Management Administration has declared the New Orleans area levee system accredited, clearing the way for the improved storm surge protection to be incorporated into National Flood Insurance Program flood maps, which should eventually lead to reduced flood insurance rates.
The Times-Picayune reports the announcement came in a letter to the Army Corps of Engineers from Frank Pagano, mitigation director for FEMA’s Region 6 office in Texas.
“Constructing the hurricane protection system was a huge accomplishment and this letter certifies that the comprehensive, integrated system of levees, floodwalls, and gates provide residents in Southeast Louisiana protection against a 100-year storm,” said U.S. Sen. David Vitter who released the letter on Feb. 20.
“I’ll continue working to ensure my provision in WRDA (Water Resources Development Act) requiring the Corps to perform future levee lifts so that the system remains accredited (and) is included in the final conference report.”
Ken Holder, a spokesman for the corps’ New Orleans District office, said, “We’re very pleased that the system has been accredited and that we will be able to go into the upcoming hurricane season for the first time with an accredited levee system.”
Holder said the levee improvements have cost about $11.8 billion so far. The corps still has $2.6 billion from post-Katrina appropriations aimed at improvements to area levees and drainage, including more than $600 million for building permanent closure and pump stations at the ends of the 17th Street, Orleans Avenue and London Avenue canals.
For the New Orleans levees included in the accreditation decision, the corps also must still install armoring, a combination of grass and geotextile fabric designed to reduce erosion. It also must complete several environmental improvements in the area to mitigate for environmental damage that occurred during the levees’ construction.
The raising of a stretch of levees in Plaquemines Parish that serve as protection from both Mississippi River flooding and storm surge moving up the river during hurricanes also is still under construction.
Interior drainage projects in New Orleans and Jefferson parishes and the raising of non-federal levees in the New Orleans to Venice system in Plaquemines Parish also are still being completed.
The accreditation decision follows a formal certification process conducted by the corps, which had to prove to FEMA’s satisfaction that the levee improvements will protect interior areas from the effects of surges caused by a hurricane with a 1 percent chance of occurring in any year, a so-called 100-year storm.
The result is that the portions of new flood maps that include the levee system will show that areas behind the levees are protected, meaning they will be marked as a shaded Zone X – areas that would see significantly lower flood insurance rates.
However, areas within the levee system that are still subject to flooding from other causes, such as poor drainage during rainfall events, would still be given an AE rating, with rates higher than Zone X. Areas outside the levee system could still be rated at even higher risk levels, with corresponding insurance rates.
The rate maps showing the new changes have not yet been approved by local parishes. Some parishes have specific objections to the heights shown on some parts of the maps, both inside and outside the improved levees. Until the parishes reach agreement with FEMA, the new rates won’t go into effect.
The accreditation of the levees will remain in effect until the FEMA flood maps are updated again, which will require the corps to again certify to FEMA that the levees meet the 100-year requirements.