There is a major issue facing the rebuilding of businesses in areas of the Coast near waterways where flood levels were high. In areas like East Biloxi, FEMA is recommending that Base Flood Elevations be increased in height by four to eight feet.
The problem is, retail doesn’t usually work on the second level of buildings. People are accustomed to walking into a store on the street level, and might bypass stairs to opt for visiting another store elsewhere that doesn’t have them.
“Retail can’t go up,” says Chevis Swetman, president and CEO of People’s Bank on the Coast. “If you have retail customers who have to walk up stairs to get in, it isn’t going to happen. You have just killed the retail development of the neighborhood.”
There are alternatives for business rebuilding. While it isn’t an alternative for homes where lives could be put at risk by residents staying during a hurricane, businesses can rebuild on the ground level by using what is known as flood-proofing, said Susan Wilson, National Flood Insurance Program (NFIP) group supervisor for Hurricane Katrina in Mississippi.
In Special Flood Hazard Areas designated as Zone A, non-residential buildings may be floodproofed in lieu of elevating the lowest floor to the Base Flood Elevation. Floodproofing is not an option in the Coastal High Hazard Areas, designated on the Flood Insurance Rate Maps as Zone V or velocity zone.
The V Zones are the areas where storm surge and wave action produces the most damage. Wilson said non-residential structures in zones starting with “A” can be either elevated or flood proofed. There can also be a combination of elevation by the placement of fill or construction of an elevated foundation, like piers, or elevation in combination with flood proofing.
Flood proofing means non-residential business buildings must be designed, engineering and constructed so walls are impermeable to the passage of water. Utilities are installed so they are not impacted by flooding. And there must be a means for sealing off the building openings when a storm is coming.
“There are a minimum number of openings, and some kind of closure devices that would effectively seal the building off,” Wilson said. “In a non-residential situation, we assume businesses are in a better position to have that type of building designed professionally so it would be flood proof. The building owners also must have an operation and maintenance plan to implement in advance of the storm to bring in the closure panels and install them so by the time the storm or flood occurs, the building would be essentially sealed. Buildings must be designed and certified by architects or engineers to be flood proof. They must be able to withstand water pressures.”
Currently all the Gulf Coast communities in Mississippi participate in the NFIP. They have adopted and enforced local programs of floodplain management that comply with the basic minimum requirements of NFIP. FEMA and the NFIP are encouraging communities on the Coast to adopt higher base flood elevations based on more current data.
FEMA has released an advisory Base Flood Elevation map that will show the areas inundated by Katrina, as well as the advisory base flood elevations. Revised Flood Insurance Studies and Flood Insurance Rate Maps (FIRMs) are expected out in 18 months to two years. Areas at the advisory base flood elevation are expected to have a 1% chance of flooding in a year (a 100-year flood event). Katrina was more like a 200-year flood event in some areas, so the new advisory base flood elevations are not as high as Katrina flood levels.
“It is important to understand that we can have a flood event that exceeds the base flood,” Wilson said. “Some people think we could never have a flood event that exceeds what is shown on the map. Katrina provided ample evidence that we could have a flood event that exceeds that by quite a bit. We are encouraging the communities to consider adoption of the advisory base flood elevations to govern redevelopment. We suspect current effective flood studies underestimate the true flood risk.”
Harrison and Jackson counties have adopted the new advisory Base Flood Elevations, while harder hit Hancock County has decided to remain with the current Base Flood Elevations.
There are a number of commercial areas on the Coast that are in V zones. That means the flood proofing option isn’t available. At the Mississippi Renewal Forum, Miami architect Andrés Duany and others suggested that to preserve business districts in V zones, performance codes should be used instead of the present prescriptive codes that require building to a certain elevation.
Performance codes could allow things like wet flood proofing and hardening the building so it could “take a bath” every 30 years with minimal damage. There would have to be devices such as breakaway walls in V zones to allow water to flow freely underneath the structure. NFIP regulations allow for communities to let those areas below the lowest elevation be enclosed with breakaway walls that are designed, engineered and certified to break away without damage to structure. These areas can only be used for storage, parking and building access.
Wilson said FEMA only considers wet flood proofing acceptable under limited conditions. The community would have to pass variances to allow businesses to use wet flood proofing.
“It may be an option in limited situations, for example, for the port facility at Gulfport because those buildings are what we consider to be functionally dependent. They must be located in close proximity to water in order to perform their function,” she said. “Port facilities have to be located immediately adjacent to the water for cargo to be stored temporarily. But wet flood proofing should only be used in very limited circumstances. Generally speaking, the options for non-residential buildings under the NFIP are to elevate on fill, foundation system or flood proofing in zones A. In the coastal high hazard V zone, buildings must be elevated on pilings or columns.”
Each city or county has its own flood plain management regulations, and some differ from others. Some communities have recognized the risks and, as a result, adopted a higher regulatory standard than the minimum regulations of the NFIP.
“Anybody rebuilding anywhere in the coastal area of Mississippi is best advised to contact local permitting officials about what they are going to require to redevelop in those areas,” Wilson advises.
While it has been well publicized the many homeowners on the Coast who flooded didn’t have flood insurance, the same is true with businesses. Wilson recommends businesses at risk carry flood insurance.
“One of the things a lot of people didn’t realize going into this disaster is that business owners could get up to $500,000 in flood insurance not only on the building, but the contents or inventory,” Wilson said. “A renter of a non-residential building can insure their inventory up to $500,000. I think a lot of business owners were unaware that coverage was available to them.”
Contact MBJ contributing writer Becky Gillette at firstname.lastname@example.org.