On October 30, 2023, the Technical Mapping Advisory Council (TMAC) recommended that FEMA implement six flood mapping changes. The objectives:
- Reduce the number of uninsured losses
- Reduce future flood losses compared to maintaining the status quo
- Improve transparency around the potential impacts of climate change and proposed development
SFHA and FPA Definition Recommendations
FEMA currently defines a Special Flood Hazard Area (SFHA) as land “subject to a 1 percent or greater chance of flooding in any given year.” The SFHA may contain several different zones that show different degrees of risk. Historically, FEMA has equated the SFHA with “floodplain” or “flood-prone area” (FPA).
TMAC recommends redefining these terms to give them different meanings. TMAC also recommends using a higher standard of accuracy (95% confidence level as opposed to 50%), but more on that later.
If FEMA adopts the recommendations, the term “Special Flood Hazard Area” would apply to areas that currently require flood insurance for mortgages made by federally regulated lending institutions.
The term Flood-Prone Area, on the other hand, they argue, should be reserved to reflect future risks from climate change and development. See below.
Why separate the two? Lenders would face resistance to enforcement of the insurance-purchase mandate if it meant requiring flood insurance on homes or businesses not yet in the 1-percent-annual-chance floodplain.
But having a separate, second definition that reflects future risk could help floodplain managers lower the probability of future flooding for homes under construction by applying to building codes, elevation requirements, and more. It could also give home buyers additional information on which to base their decisions.
Recommendation for Higher Confidence Limits
Because of a perceived rise in flood occurrences on properties lying outside the SFHA, the lending community has become more suspicious of the standard’s accuracy. People see the SFHA’s flood insurance requirement as a binary choice. “I need it or I don’t.”
But the current definition is based on the AVERAGE chance of flooding. That means 50% of properties would have a higher risk than indicated and the rest would have a lower chance.
After a flood, surprised borrowers sometimes blame their mortgage companies. “How come you didn’t tell me I was at risk?” Many buyers conclude they are safe based on a misunderstanding of technical details related to the 1% annual-chance standard.
The new standard proposes a 95% confidence interval as opposed to an average risk. That would include homes expected to flood in all but 5% of floods. A confidence interval in statistics is another way to describe probabilities.
TMAC argues that an easily understood and interpreted standard would balance safe land use with economic benefit. It would also protect lenders, educate buyers, and encourage borrowers to act responsibly.
Redefining Flood-Prone Areas
The illustration below depicts TMAC’s concept for developing the FPA elevation and associated boundary. It includes an extra safety margin for climate change and future development.
This “freeboard factor” would be a proxy for estimated future conditions.
However, TMAC recognizes there may not be:
• Adequate land-use information to determine the impact of future development or
• Planned development expected to change flood conditions or
• Sufficient information to determine the impacts of climate change.
0.2% Annual Chance Flood Recommendations
For consistency and ease of communication/education, TMAC recommends applying the 95% confidence limit to .02% annual chance floods also. These were previously known as 500-year floods.
Bringing fill dirt into a floodplain to elevate homes reduces the amount of storage capacity for floodwaters. Fill can also often increase hazards to nearby property owners and have negative environmental impacts.
Currently, a maze of regulations governs the use of fill. TMAC recommends consolidating and clarifying all fill requirements in flood-prone areas.
Among the recommendations: Prohibiting fill as a floodproofing technique.
Notice of Fill Impacts
TMAC recommends that FEMA should require participating communities, as part of permitting duties, to quantify and put on file the impacts of proposed fill and other development on flood height and the environment prior to issuing fill permits.
When increases in flood elevation or potential negative environmental consequences are found and cannot be mitigated, at a minimum, property owners and appropriate environmental agencies should be notified prior to issuing permits.
Many such requirements already exist for floodways. This recommendation would expand the requirement to floodplains.
The TMAC report observes that large amounts of fill placed in the flood fringe can potentially create significant impacts upstream, downstream or both. But there are no impact notification requirements in many communities and states.
“This is in effect a risk transfer to uninformed landowners and environmental stewardship organizations,” says the report.
Status of Adoption Unclear at this Point
Due to the holidays, I’ve had trouble determining where FEMA stands in adopting these recommendations. TMAC clearly labels these “interim recommendations.”
Congress plans to take up the subject of flood insurance in January or February. So we may get some clarity then. Check back often.
The problem with proposed changes to regulations is that they create winners and losers. People with risky land to sell may not want fuller disclosure. On the other hand, those in danger of flooding may want more information.
The states seem divided on flood-insurance reform. Some want to continue encouraging floodplain development by keeping NFIP premiums low. Others want to avoid burdening taxpayers with NFIP bailouts. They claim higher premiums help avoid development of flood-prone land.
It could take years to find suitable compromises. In the meantime, buyers beware. Perhaps TMAC’s recommendations will help improve awareness.
Posted by Bob Rehak on 12/27/2023
2311 Days since Hurricane Harvey