Existing Structures in the Floodplain

FACT: Floods are the nation’s most common and costly natural disaster and cause millions of dollars in damage every year. Floods cost America, on average, $8.2 billion each year (according to 2015 data). Recovering from just one inch of water inside your building can cost about $27,000. Learn about The BIG Cost of Floods.

FACT: Homeowners and renters insurance do not typically cover flood damage.

FACT: Floods can happen anywhere--More than 20 percent of flood claims come from properties outside the high risk flood zone.

FACT: If you home is located with the special flood hazard area, your home has a 26% chance of being damaged by a flood during the course of a 30-year mortgage, compared to a 9% chance of fire.

FACT: Flood insurance can pay regardless of whether or not there is a Presidential Disaster Declaration.

FACT: Most federal disaster assistance comes in the form of low-interest disaster loans from U.S. Small Business Administration (SBA) and you have to pay them back. FEMA offers disaster grants that don't need to be paid back, but this amount is often much less than what is needed to recover. A claim against your flood insurance policy could and often does, provide more funds for recovery than those you could qualify for from FEMA or the SBA--and you don't have to pay the money back.

FACT: You may be required to have flood insurance. Congress has mandated federally regulated or insured lenders to require flood insurance on mortgaged properties that are located in areas at high risk of flooding. But even if your property is not in a high risk flood area, your mortgage lender may still require you to have flood insurance.

Elevation Certificates

Your insurance agent may ask you for an Elevation Certificate (EC). This certificate verifies your building's elevation compared to the estimated height floodwaters will reach in a major flood in a high-risk flood area.

A property owner in a high-risk flood area always has the right to purchase an EC, which may reduce your flood insurance premium. Please contact a licensed professional surveyor for further information about obtaining an Elevation Certificate. PDS may provide a review of any elevation certificate for completeness and will keep a copy on file as a permanent record associated with your structure. 

Improvements to Structures within the Floodplain

The construction requirements for changes to existing floodplain buildings depend on when the structure was build (or substantially improved) and the nature of the proposed changes.

Substantial Improvement Rule

If the cost of improvements exceeds 50 percent of the market value of the building, then the entire structure must be brought up to current floodplain management standards.  For many existing buildings, this can require a major investment to elevate the structure, fill the basement, or make other changes to conform to current rules.  The “cost of improvements” must include the market value for all materials and labor, even if the out-of-pocket expenditures are less (for example, the owner does some of the labor).  The “cost of improvements” does not include the cost of repairs required to remedy existing health, safety, and sanitary code violations.   If the project is implemented in stages, FEMA requires that the entire project be counted as one for the purpose of determining whether it constitutes a substantial improvement.

Exception for Some Lateral Additions

When an addition that increases the square footage of a structure is a substantial improvement (i.e. the cost exceeds 50% of the value of the structure), the addition must be elevated or floodproofed in compliance with current standards.  However, in non-coastal floodplains, the existing building may not have to be brought into compliance if:  (1) no significant improvements are made to the existing structure and (2) the common wall of the existing structure is retained (except for a doorway).

Substantial Damage

If a floodplain structure is damaged by flood, fire, or any other cause and the cost to repair the damage exceeds 50 percent of the market value of the building before the damage occurred, then any repairs are considered a substantial improvement, regardless of the actual repair work performed.  The determination of substantial damage is based on the true cost of bringing the building back to its pre-damage condition using qualified labor and materials obtained at market prices.  If the owner had flood insurance and the building was substantially damaged by a flood, the Increased Cost of Compliance coverage will help with the extra cost of complying with this requirement.

Exception for Historic Structures

Historic structures[1] are exempt from the substantial improvement requirements, provided that the project maintains the historic status of the structure and incorporates all possible flood damage reduction measures.

Minor Improvements to Pre-FIRM Structures

Modifications to a pre-FIRM structure that do not constitute a substantial improvement still require a floodplain development permit.  The project should incorporate methods and materials that protect against flood damage "to the greatest extent practical."  This can involve the use of flood-resistant materials, location of mechanical and electrical equipment above the flood protection level, and other techniques. 

Consult with PDS or your local floodplain administrator and review your local floodplain regulations to determine how to proceed with your project.

Flood Preparedness

Know your flood risk and be prepared before, during and after a flood event. Please review the following resources:

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