If your new swimming pool construction project is located in a high-risk flood zone, your municipality may require an elevation certificate as part of the permitting process — and chances are you already have one. This article explains what the Base Flood Elevation (BFE) is, what an elevation certificate is and when and why you may need to obtain one.
Base Flood Elevation (BFE)
The Base Flood Elevation (BFE) is the computed elevation, in reference to the sea level, to which floodwaters are anticipated to rise in a particular area during a base flood, which is usually the flood that has a 1% chance of being equaled or exceeded in any given year (also known as the 100-year flood).
For example, if the BFE in your area is 6 feet and the floor of your house also has an elevation of 6 feet relative to the same sea level, then there is a 1% chance each year that floodwaters will reach the level of the floor of your house.
What is an Elevation Certificate?
An elevation certificate is an official document used to provide information on the elevation of a building (your home) relative to the base flood elevation (BFE) in Special Flood Hazard Areas (SFHAs) — commonly know as “flood zones” — as designated by the Federal Emergency Management Agency (FEMA).
When Is an Elevation Certificate Required
If your property is located in a FEMA-designated flood zone and you have a mortgage from a federally regulated or insured lender (such as FHA, VA, or USDA loans), flood insurance is mandatory, and an elevation certificate is required for assessing flood risk and determining flood insurance premiums. Private lenders also generally require flood insurance (and elevation certificates) for homes in high-risk flood zones as a condition of the loan, even if the mortgage is not federally backed. It is likely, therefore, that you already have an elevation certificate.
Aside from insurance purposes, the BFE is crucial for swimming pool design and construction in areas prone to flooding, even if they not technically designated by FEMA as SFHAs. Our pool design engineers use the BFE for the calculation of the uplift force on in-ground swimming pools. The uplift force, also known as hydrostatic uplift, occurs when groundwater exerts upward pressure on the pool structure. This force can be significant, to the extent that it may cause the pool to shift or “pop up” , especially when the pool is empty or only partially filled.
“Pool popping” is a phenomenon that occurs when an in-ground swimming pool is pushed out of the ground due to hydrostatic pressure from groundwater. This typically happens when the pool is emptied or partially drained, causing a significant reduction in the weight that counteracts the upward force of the groundwater.
Look for your elevation certificate in your settlement papers. It’s often attached to survey if you have it in PDF format.
Digitally Signed Elevation Certificates
There are only a few municipalities in South Florida which still process permit applications in paper form. Most require digitally signed documents, but may still accept the scanned form of a physically signed and sealed elevation certificate. Larger cities, such as Fort Lauderdale, will insist on a digitally signed elevation certificates in PDF format.
For more detailed information about pool construction protocols, you can also check our article on Understanding Swimming Pool Barrier Requirements for Residential Pools in Florida.