Increasing Flood Resilience: Designing and Building for the Future

In July 2023, FEMA released a report based on their analysis of Hurricane Ian in Florida. This report, titled "Designing for Flood Levels Above the Minimum Required Elevation After Hurricane Ian (Recovery Advisory 1)," provides critical insights that extend beyond state boundaries and offers valuable lessons for designing resilient buildings.

FEMA’s report underscores the vital importance of going beyond the minimum regulatory requirements to better prepare for future flood events. This approach is fundamental in enhancing overall flood resilience.

Where we are today

To provide context, the National Flood Insurance Program (NFIP) is a program that makes flood insurance available in states and communities that agree to adopt and enforce minimum floodplain management requirements. Participation in the program is voluntary and is contingent on compliance with the established requirements. 

To participate in the NFIP, communities must use Flood Insurance Rate Maps (FIRMs) that delineate Special Flood Hazard Areas (e.g., Zone VE, Zone AE, X) to reflect flood conditions expected during a base flood. FIRMs show the Base Flood Elevation (BFE) associated with a flood that has a 1% annual chance of occurrence.

The minimum standards for the NFIP require new buildings, buildings with substantial damage, and buildings undergoing reconstruction or substantial improvement to be elevated so that their lowest floor (or the lowest horizontal structural member of the lowest floor) is at or above the established BFE.

The report highlights some of the gaps and limitations associated with FIRMs, focusing on how implementing stricter maps, elevating structures above the BFE, and committing to other design changes can significantly enhance resilience.

Addressing limitations of FIRMs

An important note about FIRMs is that they rely on models that use the best available data at the time they are prepared. However, there are critical limitations, some of which include: 

• Older FIRMs may no longer accurately represent the location and actual risk.
• The BFE is not representative of any individual storm, but is derived from an analysis of many potential and historical storm responses.
• Flood elevations can and do exceed the BFE, and extend beyond the mapped boundaries of the SFHA.

To tackle some of these limitations, stricter regulations can be effective. Two recommendations were provided in the report:

• Design a Coastal A Zone. Improve the flood map by delineating the Limit of Moderate Wave Action (LiMWA). The LiMWA is depicted as a solid black line with arrows pointing in the direction of the area with additional wave-associated risk. The area between the Zone V boundary and the LiMWA is known as the Coastal A Zone.  

• Implement Freeboard Standards. Require additional feet of elevation to meet a Design Flood Elevation (DFE). The “freeboard” accounts for the space between the BFE and the DFE, compensating for the unpredictable factors that could contribute to flood heights greater than anticipated (ie: wave action, bridge openings, and the hydrological effect of urbanization of the watershed).

Forerunner’s floodplain management software can be a helpful tool for implementing these types of regulations. The software maps out the floodplain in a community and consolidates all of the data into individual property profiles. Forerunner automatically detects and highlights Coastal A zones for both internal and public reference - and if a community regulates those zones, can help with Elevation Certificate management and compliance (using the Elevation Certificate Error Detection feature). Forerunner can also automatically apply freeboard standards to the Base Flood Elevation (BFE) listed for each property, so floodplain managers can easily calculate the Design Flood Elevation (DFE) and ensure everyone is clear on the requirements.

Preparing for future conditions

Another important point is that FIRMs reflect the conditions of the time that they were made. They do not often factor in future conditions, such as sea level rise, subsidence, shoreline erosion, increased storm frequency/intensity, land use change, and levee settlement and failure. Most buildings last many decades, so it is important to consider these factors when designing new buildings and undergoing significant construction.

The report provides a 14-step process for determining flood elevations based on future conditions and guidelines for anticipating future flood zones. They provide a comprehensive framework for decision-making, enabling stakeholders to make informed choices about building elevation.

One of Forerunner’s partners, Clearwater, Florida, is a great example of a forward-thinking community. They adopted a new floodplain management ordinance in 2018, mandating two feet of freeboard, more stringent enclosures, adjustments for critical facilities, and restrictions on manufactured homes. Shortly thereafter, they established a Coastal A Zone (preemptively), conducted a Coastal Vulnerability Assessment, and teamed up with Forerunner. Forerunner consolidated their flood maps in one place, automated their tracking for Substantial Improvement and Damages, reduced their time spent on reviewing Elevation Certificates, and helped increase transparency with residents. So far, the steps they have taken as a community have helped them maintain their CRS participation, modernize construction and development, and protect the shoreline. They believe their actions now will set them up for a successful future.

At Forerunner, a big part of our work is anticipating challenges and building solutions to meet local needs. We’ve designed our software to enable and empower floodplain management teams and communities as we navigate the path forward. Forerunner consolidates all floodplain management data into one central platform, allowing floodplain managers to simplify workflows, collaborate efficiently, and plan more effectively for development. We consolidate permits, Elevation Certificates, and other key documents on a property’s profile, minimizing tedious information look-ups and streamlining permit reviews. We also make it easy for residents to find the documentation and data that they need to make more informed decisions, without requiring extra assistance.

Additional considerations

There are other factors to consider when selecting the right elevation requirements. Some communities may limit building height, operate with unique building codes, have nuances for building type, or be influenced by a federal grant. Things like preliminary FIRMs, age of effective flood analysis, and risk tolerance also come into play. 

The report goes further by outlining additional design considerations that can help mitigate flood damage. It highlights the importance of calculating design loads based on future stillwater elevation and wave conditions, considering strong connections to ensure a continuous load path, and using flood damage-resistant materials. These measures collectively bolster a building's resilience against both flood and wind hazards.

The aftermath of Hurricane Ian underscores the urgency of designing buildings that can withstand future flood events. Recovery Advisory 1 offers valuable insights, guiding designers, planners, homeowners, and operators on the current landscape and the strategic choices that can help pave the way for a more flood-resilient built environment.

We will continue to build more features to support new regulations and changes. If you are interested in learning more about Forerunner, we would love to connect! Please reach out to support@withforerunner.com or request a demo.