The City of Isle of Palms participates in the National Flood Insurance Program (NFIP), and in this participation, the city adopts local ordinances whose goals are to reduce the risk of losses in the flood plain. During the permitting process, the building department will conduct a review of the applicable ordinances to ensure compliance. All new construction and substantial improvements are required to meet current flood zone standards as determined by the flood insurance rate maps (FIRM) for the City of Isle of Palms.
New construction and additions located in flood zone VE, Velocity Zone, and the construction drawings are required to be stamped and signed by an architect or engineer. Also, a V-Zone certification is required to be on the plans. The forms designed by FEMA are available at the building department.
Projects located in the AE flood zone, whether new construction or addition would not necessarily require the stamp of an architect, unless, specifically requested by the building official.
Base Flood Elevation (B F E)
Within the designated flood zones AE and VE there is a corresponding number such as 13,14,15, etc., which determines the height with which the structure is to be elevated. For example: AE-13 would require the first finished floor to be elevated to meet or exceed 13 feet mean sea level (MSL). If the flood zone is VE -16, the first horizontal member under the structure must meet 16 feet (MSL). All materials used below the base flood elevation are required to be class 4 or 5 flood-resistant materials in accordance with the Technical Bulletin 2-93 as published by the Federal Emergency Management Agency. Copies of the Technical Bulletin may be obtained from the building department.
This provision applies to existing structures which are below the minimum base flood elevation, as shown on the current flood insurance rate maps. Prior to the issuance of a building permit for repairs, renovations, alterations or additions a substantial improvement review would be conducted. The proposed improvements to the structure cannot exceed fifty percent (50%) of the appraised or accessed value of the structure, excluding the lot. For example; if the structure is appraised or accessed at $100,000 the amount of improvements allowed would be $50,000 - this is in effect for a period of five years. If during the five year period the improvements exceed 50% the structure would then have to be brought into compliance with current flood zone standards. A substantial improvement documentation packet can be obtained at the building department.
Substantial Damage/Substantial Improvement Repair/Reconstruction Affidavit
Preliminary Flood Insurance Maps
September 19, 2016
The City has received a preliminary copy of new Flood Insurance Rate Maps (FIRMs) from FEMA for review and comment. According to FEMA, a series of public meetings will be scheduled in the fall to provide the public an opportunity to ask questions and express concerns. After the review and appeal periods end, FEMA will prepare final FIRMs, which the City will adopt through a local ordinance. FEMA expects this process to take at least a year. In the meantime, the current flood maps will remain in effect.
When reviewing these preliminary maps you may note dramatic differences from the prior maps and the proposed new ones. One difference contributing to this change is the reference elevation that these maps are based on has changed from previous flood maps from the National Geodetic Vertical Datum of 1929 (NGVD 1929) to the North American Vertical Datum of 1988 (NAVD 1988). This new reference point is approximately one foot lower. Therefore, an elevation requirement of 13 feet on an older flood map is the same elevation as 12 feet on these proposed maps. Additionally, the City has a local requirement that requires an additional foot of elevation above the FIRM requirement, which improves the City’s Community Rating System (CRS) score and provides for a flood insurance discount for property owners.
Because most, if not all, of the elevation requirements will be lower under these new proposed maps, if they are adopted as currently proposed, the City may consider passing a local ordinance that would increase the elevation requirement to maintain the disaster resistance of the community, improve the City’s CRS score and provide for additional insurance discounts for property owners.
The proposed flood maps can be found here. If you have specific questions about the flood regulations as they pertain to your property, you may call the Building Department at 843-886-9912. This site will be updated on public meetings as they are announced.