Another Op-ed on Flood Maps Misses the Point
I have nearly 35 years of professional experience in South Louisiana hydrology, including extensive work on flood risk for the Amite River Basin since 2001. First of all, kudos to The Advocate for the great work in covering the flood and flood risk information over the last two weeks. Unfortunately Mr. Robert Taylor’s letter “Flood mapping needs to change” which appeared on Monday August 29th continues to perpetuate six critical misunderstandings about flood maps and the National Flood Insurance Program (NFIP) maps. Since Mr. Taylor is the CEO of Louisiana Bankers Association, it is important to address these misunderstandings.
1. Flood maps technically belong to the local community—and the community can update the maps anytime they wish. Because local communities do not often initiate/fund updates, and because FEMA has a long backlog of requests to assist local communities in map updates along with a tight budget, we should, as a practical matter, expect many or most NFIP maps to be outdated.
2. Ironically, when local communities do initiate a map update themselves, it is almost always to REDUCE flood zones. This reduces flood insurance premiums and saves homeowners money over the short term.
3. Keep in mind the name of the maps—“Flood Insurance Rate Map.” The mapping of the flood hazard is intended to simply be sufficient to support the NFIP rate determinations. For national actuarial purposes, maps only need general regional level accuracy, not rigorous accuracy at every point on the map. Even brand new FIRMs have limitations in local accuracy given the NFIP’s goals.
4. Even the best possible flood hazard evaluations, which are done for risk assessments at very sensitive locations such as major urban areas and nuclear power plants, can have statistical uncertainties of 30 percent in estimating a 100-yr (1 percent annual chance) flood depth. That equates to three feet of uncertainty on a 100-yr flood depth of 10 feet. Professional hydrologists know that estimates of flood hazard are really “scientific guesstimates”—which is one reason why investing in map updates sometimes makes little sense.
5. Virtually every Louisianan lives in a flood hazard area. No mortgage banker should ever tell a borrower that they do not “require” flood insurance. Perhaps this is appropriate as a legal matter (and only after a very carefully worded explanation during the loan closing), but NEVER as practical or financial matter!
6. Flood risk reduction would be better served if the mortgage industry in Louisiana would urge passage of a bill by our Legislature mandating that ALL borrowers obtain flood insurance.
Our state has probably lost over a billion dollars in NFIP payments this year due to underinsurance. Unfortunately, as an earlier blog post pointed out, fixating on NFIP maps will not fix the problem of underinsurance. Fixing this fundamental problem in the how the NFIP is administered requires expanding the flood risk pool to include properties in the 500-yr (0.2% percent annual chance flood risk zone) and 1000-yr (0.1% percent annual chance flood risk zone).
Editor’s Note: An earlier version of this post appeared as a letter in The Advocate on August 29, 2016.