18 flood insurance claims·$119,585 paid·4 federal flood & hurricane disasters
Share of the whole county outline, rivers and lakes included; parts FEMA hasn’t mapped count as zero.
Shaded areas are FEMA’s mapped flood hazard zones in and around Powell County, Montana. Zoomed out they are simplified; at street level the map switches to FEMA’s exact layer. Tap anywhere to check that spot, or search an address above.
River overflow dominates the flood profile of Powell County, accounting for 17 of the 19 recorded events in the last 30 years alongside 2 flash flood events.
Spring flooding typically results from a combination of heavy mountain snowpack and heavy rainfall, as occurred in June 2011 and May 2018 when above-normal snowpack and warm temperatures or cut-off low pressure systems drove significant river rises. Summer convective activity also presents localized risks, such as the heavy rainfall and thunderstorms along the Interstate 90 corridor in August 2014.
National Flood Insurance Program records indicate that property owners in designated Special Flood Hazard Areas should pay the most attention, specifically those in Zone A, which logged 6 claims with an average payout of $20,975 and an average recorded water depth of 1 inch. Residents with properties in Zone UNKNOWN also merit close attention, having accumulated 11 claims with an average payout of $3,543 and an average recorded water depth of 1 inch.
Summary written from NOAA storm reports and NFIP claims for this county. Not a prediction.
In flood insurance claims here that reported a flood depth, the average was 1 inches.
Drawn to scale against an 80-inch door. Even a few inches soaks flooring, the bottom of the drywall and anything plugged in near the floor.
Average of the depths reported on claims (zero and implausible values left out); FEMA’s record doesn’t say exactly where each depth was measured. Source: OpenFEMA NFIP claims.
The worst year was 1981, with 11 claims and $35,434 paid, the year of Severe Storms & Flooding.
Bar height is scaled by square root so ordinary years stay visible next to the worst one. NFIP claims by year of loss. Source: OpenFEMA.
16 federal disaster declarations since 1975, 4 of them floods, coastal storms or hurricanes.
| Disaster | Began |
|---|---|
| Windy Rock Fire | Aug 26, 2025 |
| Straight-line Winds | Jul 24, 2024 |
| Flooding | May 1, 2018 |
| Rice Ridge Fire | Aug 28, 2017 |
| Severe Storms And Flooding | Apr 4, 2011 |
| Hurricane Katrina Evacuation | Aug 29, 2005 |
| Lincoln Fire Complex - 08/14/2003 | Aug 14, 2003 |
| Severe Winter Storms | Jun 3, 2001 |
Weather and water disasters only; most recent first. Source: OpenFEMA Disaster Declarations.
19 since 1996: 2 flash floods and 17 river or area floods.
| Event | Date | Damage |
|---|---|---|
| Flood | Jun 19, 2018 | $70,000 |
| Flood | May 10, 2018 | — |
| Flash Flood | Aug 15, 2014 | $500 |
| Flood | Jun 7, 2011 | — |
| Flood | May 10, 2005 | — |
| Flood | Mar 13, 2003 | — |
| Flash Flood | Jul 3, 1998 | — |
| Flood | May 1, 1997 | $69,000 |
— = no damage estimate in the record. Source: NOAA Storm Events Database.
Flood · Jun 19, 2018. A cut-off low pressure system brought 1 to 3 inches of rain to the upper part of the Clark Fork River Basin resulting in significant stream and river rises. High elevation snow melt also added to the water flow issues.
Flood · May 10, 2018. The combination of above normal mountain snow-pack up to 200% of normal and warmer than normal temperatures in the month of May led to continued and new river flooding. Missoula County reported that the tally for damage was to the amount of $450,000.
Flash Flood · Aug 15, 2014. Several upper level waves moved from south to north during the day around an upper level low that was centered between central Washington and Oregon. One of these impulses initiated thunderstorms across southwest Montana and brought hail and heavy rainfall especially to the Interstate 90 corridor between Garrison and Butte.
Flood · Jun 7, 2011. A mid level circulation over southwest Montana brought widespread heavy rainfall. This same area received significant rainfall the week before. This rainfall in addition to a heavy snow pack had saturated the ground with streams and rivers running high.
National Weather Service narratives, lightly trimmed. Source: NOAA Storm Events Database.
Every colour on the map above is a place on this drawing: where the ground sits relative to the flood FEMA plans for.
If a building in Powell County is in a high-risk zone (A or V) and its mortgage comes from a federally regulated or insured lender, or is federally backed, flood insurance is required.
Outside those zones it is optional, and often worth having: from 2014 to 2024 nearly one-third of NFIP claims came from outside the high-risk Special Flood Hazard Area. Since Risk Rating 2.0, NFIP premiums are set for each building, so the only reliable price is a quote: FloodSmart.gov or a local agent.