Major Deficiencies of FEMA FIRMs

Until [FEMA incorporates all the necessary modeling components], these maps will always be obsolete the day they come out.

–Larry Larson, Director-General Emeritus Association of State Floodplain Managers

FEMA flood maps—formally called Flood Insurance Rate Maps, or FIRMs—have become the generally accepted resource for characterizing current flood hazards. However, these maps were never intended to address the needs of risk managers or property owners; they were designed solely to implement the requirements of the National Flood Insurance Program (NFIP), such as setting flood insurance rates.

Property owners, plant operators, industry associations and regulators, engineering firms, standards bodies, and legal experts are taking note of an emerging class of actionable data such as Jupiter’s, and reassessing how their sole reliance on FEMA flood maps—while convenient—may also be insufficient, and perhaps even negligent.

This special report demonstrates seven ways that FEMA flood maps do not paint an accurate and complete picture of flood risks and shows the material impact of these shortcomings. It compares FEMA flood zone information against observed flood data during Hurricane Harvey, while benchmarking it using Jupiter’s FloodScore™ service.