(From WLOX and Associated Press reports)
The Federal Emergency Management Agency said Friday that it’s putting out interim flood elevation maps to help hurricane-ravaged Gulf Coast communities make early rebuilding decisions.
Analysts have decided that the old flood elevation levels were 3 to 8 feet too low in the three coastal counties of Hancock, Harrison and Jackson, a FEMA statement said.
Flood elevation is the height above ground at which there is a 1 percent chance water could reach in a given year.
The new elevations for Hancock, Harrison and Jackson counties were being released to Gulf Coast officials and will be included on updated flood recovery maps now scheduled for release in November.
The new maps update the existing flood elevations developed in the mid-1980s and include tide and storm data collected following Hurricane Katrina and earlier storms like Elena and Georges.
“Our goal is to help states and local communities make the best decisions while reconstructing their communities,” said Vice Admiral Thad Allen, principal federal official and federal coordinating officer for Hurricanes Katrina and Rita recovery efforts.
Todd Davison, mitigation division director with FEMA’s regional office in Atlanta, said water driven inland by Katrina far exceeded the 1 percent chance flood event, sometimes called the 100-year flood. Because of this, he said coast governments had requested that new flood maps be developed to assist with planned new construction.
Davison said FEMA would meet with coast leaders next week to go over the new maps, but “it is their option to adjust and adopt their local codes and ordinances to include these new elevations.”
Until the new maps are approved by local communities, existing elevation maps will be in force, he said.
The new maps include survey information collected in the field after Katrina and a review of storm surge data dating back 20 years.
While the new elevations are higher than the existing standard, they are below the storm surge levels reached by Katrina, a Category 4 storm. He said Katrina’s surge was well beyond the 100-year flood mark and that requiring structures be built to survive such a storm would be prohibitive.
If new elevation requirements are adopted and followed, it will mean a “significant decrease in their insurance premiums” both now and in the future. He said the standards would also benefit local communities to qualify for various federal and state programs.
Davison and Mike Womack, deputy director of the Mississippi Emergency Management Association, said the elevation changes should not mean a major change in how structures are built on the coast.
Davison said many of the structures destroyed by Katrina were built before the current requirements. And he said there were cases where older buildings had been elevated on pilings and survived the storm’s furry.
Davison said permanent maps will be released in 12 to 24 months.