Title 42 › Chapter CHAPTER 50— - NATIONAL FLOOD INSURANCE › Subchapter SUBCHAPTER II— - ORGANIZATION AND ADMINISTRATION OF FLOOD INSURANCE PROGRAM › Part Part A— - Industry Program With Federal Financial Assistance › § 4057
The rule requires FEMA’s Administrator, working with the NOAA Under Secretary, to publish a standard math formula called the COASTAL Formula within 180 days after a related protocol is set. Key terms explained in one line each: Administrator = FEMA head; COASTAL Formula = the new allocation formula; coastal State = the usual legal meaning but not a State with an operational wind-and-flood system; indeterminate loss = a damage claim where a certified NFIP adjuster (and an engineer if needed) finds only foundations or no clear physical evidence remains after a named storm; named storm = a weather system named by the National Hurricane Center with winds of at least 39 miles per hour; post-storm assessment = the assessment under the cited law; standard insurance policy = NFIP flood policy; Under Secretary = NOAA head. The formula must use the Coastal Wind and Water Event Database, Elevation Certificate or similar flood-risk data, any credible pre-storm evidence, and other measures needed to split flood versus wind or surge damage. The post-storm assessment may be used only if the Under Secretary certifies it is at least 90 percent accurate. FEMA may use the COASTAL Formula to review or pay flood parts of indeterminate claims after a Presidential major disaster, but only after the National Academy of Sciences (NAS) evaluates the formula and reports that it won’t hurt the NFIP financially and can reach 90 percent accuracy. The NAS report must be sent to four congressional committees named in the law. Up to $750,000 from the National Flood Insurance Fund is allowed to carry out the NAS review. FEMA must tell a claimant within 30 days if the COASTAL Formula was used and give a summary of results. A certified adjuster who knowingly lies about an indeterminate loss can be fined up to $1,000, paid into the National Flood Insurance Fund. Using the formula does not force FEMA or private insurers to pay, does not change policy limits, and does not create a new right to sue.
Full Legal Text
The Public Health and Welfare — Source: USLM XML via OLRC
Legislative History
Reference
Citation
42 U.S.C. § 4057
Title 42 — The Public Health and Welfare
Last Updated
Apr 6, 2026
Release point: 119-73