DNRC and county brief commissioners on preliminary FEMA flood‑insurance maps; appeal window, timeline explained

Federal, state and county officials briefed Missoula County commissioners on preliminary Flood Insurance Rate Maps (FIRMs) and the accompanying Flood Insurance Study for the Clark Fork River, Bitterroot River and Rock Creek.

Matt Heimel, Missoula County floodplain administrator, introduced the item and said the preliminary maps were issued by FEMA on Aug. 28. Nadine Wadsworth (flood hazard outreach planner) and Tracy Sears (DNRC National Flood Insurance Program coordinator) presented study scope, mapping products and next steps. DNRC staff said the study updates approximately 93 stream miles and consolidated older studies into the new preliminary maps and technical memoranda.

Presenters explained key map components: the special flood hazard area (commonly called the 1% annual chance or 100‑year flood), the floodway (stricter state and local controls), and the 0.2% annual chance (500‑year) zone. DNRC emphasized that preliminary maps are the basis for an upcoming formal 90‑day appeal and comment period and that appeals must identify a scientific or mathematical error and supply revised technical components to be considered by FEMA.

Tracy Sears noted the National Flood Insurance Program (NFIP) provides flood insurance availability and disaster‑assistance benefits to participating communities and that Missoula participates in the NFIP’s Community Rating System (CRS). “Missoula actually participates in what they call the community rating system…right now you guys are at a class 7,” Sears said, which yields an approximately 15% premium discount for property owners in the community.

DNRC staff described the public process: FEMA will publish a notice in the Federal Register, begin a 90‑day formal appeal period (typically opening six to nine months after the preliminary issuance), and, following review, may issue revised preliminaries if valid appeals are accepted. If the schedule proceeds without appeals that change maps, FEMA could issue a Letter of Final Determination and maps could become effective in mid‑ to late‑2027. Communities then have six months to adopt maps and update local regulations before the maps take effect.

Staff stressed that appeals are technical and often require surveyors or engineers; DNRC and Missoula County can provide data and guidance to parties considering an appeal. The presentation included DNRC’s online flood hazard viewer showing areas proposed for addition, removal or no change relative to the effective maps, depth grids useful for emergency planning, and LOMA/LOMR (letter of map amendment/revision) implications for some properties.

Commissioners and attendees asked about how different county departments were using preliminary maps; the floodplain administrator said the county continued to use effective (federal) maps for floodplain permitting but that other departments (for example, environmental health) may use preliminary data as it becomes available for regulatory planning. DNRC and county staff offered to assist property owners exploring LOMA/appeal options and to coordinate outreach during the formal appeal period.

A representative of the Missoula Conservation District thanked the county and DNRC for the work and said up‑to‑date mapping and inclusion of riparian/channel migration information supports longer‑term planning and resiliency.