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3 Recommendations The BPAT's recommendations are presented below. Engineering design drawings are also presented that illustrate the recommendations and provide details that can be used to enhance building performance under hurricane and coastal flood conditions. 3.1 APPLICATION OF V-ZONE AND A-ZONE DESIGN AND CONSTRUCTION REQUIREMENTS NFIP V-Zone construction requirements specifY that new construction be elevated on piles, posts, columns, or piers and that the bottom of the lowest horizontal structural member (e.g., floor beam, joist) be at or above the BFE. Depending on the dimensions of those structural members, the resulting lowest floor elevations can be as much as 1.5 feet above the BFE. By comparison, NFIP A-Zone standards for new construction require that the lowest floor of the structure be at or above the BFE. FIRMs accounting for wave effects were adopted by the communities in the study area between 1985 and 1987, prior to changes in V-Zone mapping procedures that extended coastal V- Zones to the landward toe of the primary frontal dune. The BPAT believes that this factor, coupled with a decade of long-term erosion, resulted in narrow V-Zones and an underestimation of actual risk along or near the shoreline, which increased the exposure of some post-FIRM A- Zone construction to V-Zone flood forces. 3.1.1 FEMA To ISSUE REVISED FIRMs FEMA will address the V-Zone issue discussed above by completing restudies and revisions to the FIRMs as necessary for the communities in the study area. Preliminary revised maps for the affected communities will not be completed until 1997; thus, the majority of post -Opal reconstruction will be governed by the FIRMs in effect at the time of the storm and by State CCCL requirements. Until the revised FIRMs are completed, the affected communities should consider studying local coastal flooding conditions that occurred during Hurricane Opal to determine whether areas in coastal A-Zones, as well as areas within several hundred feet of the Gulf of Mexico shoreline, are actually subject to V-Zone flood forces. If such areas are identified, the affected communities should strongly encourage the owners of new construction and substantial improvements to existing structures within those areas to conform with V-Zone construction standards and to provide several feet of freeboard above the BFEs shown on the current FIRMs. 3.1.2 COMMUNITIES USING HIGHER STANDARDS IN COASTAL A-ZONES The benefit of applying more stringent requirements to new construction in coastal A-Zones in the study area was illustrated by the performance of recent post-FIRM A-Zone construction in the City of Pensacola Beach during Hurricane Opal. Under the jurisdiction of the Santa Rosa Island Authority (SRIA), the city enforces V-Zone construction standards in all of the barrier island areas shown as A-Zones on its current FIRM. Within the same A-Zones, the SRIA also HURRICANE OPAL IN FLORIDA 3-1