10 flood insurance claims·$8,245 paid·1 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 Silver Bow 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.
Silver Bow County experiences a flood risk profile where standard riverine flooding slightly outpaces flash flooding. Over the last 30 years, NOAA recorded 14 flood events and 6 flash flood events.
Severe weather events have historically driven flash flooding across the area. For example, a strong low pressure system and cold front produced flash flooding in the city of Butte on August 6, 2009, when up to an inch of precipitation fell in 30 to 45 minutes alongside baseball-sized hail and 70 mph winds. Additionally, anomalous atmospheric moisture and slow-moving thunderstorms caused heavy rain and localized flooding on June 6, 2023, while monsoonal subtropical moisture brought heavy rainfall on August 1, 2021.
National Flood Insurance Program records indicate historical claims in both high-risk and moderate-to-low risk areas. Zone A properties account for 7 claims with an average payout of $1,543 and an average recorded water depth of 7 inches. Zone X properties account for 3 claims with an average payout of $2,073 and an average recorded water depth of 0 inches. Property owners in Zone A should pay the closest attention to this flood risk.
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 7 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 2011, with 5 claims and $5,419 paid, the year of Severe Storms and 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.
7 federal disaster declarations since 1981, 1 of them floods, coastal storms or hurricanes.
| Disaster | Began |
|---|---|
| Hurricane Katrina Evacuation | Aug 29, 2005 |
| Southwestern Zone Two Fire Complex | Aug 5, 2000 |
| Wildfires | Jul 13, 2000 |
| Severe Storms, Flooding, And Ice Jams | Feb 4, 1996 |
| Severe Storms & Flooding | May 27, 1981 |
Weather and water disasters only; most recent first. Source: OpenFEMA Disaster Declarations.
20 since 1996: 6 flash floods and 14 river or area floods.
| Event | Date | Damage |
|---|---|---|
| Flash Flood | Jun 6, 2023 | $15,000 |
| Flash Flood | Aug 1, 2021 | — |
| Flood | Mar 19, 2017 | $1,000 |
| Flash Flood | Aug 6, 2009 | $1,000 |
| Flash Flood | Aug 6, 2009 | — |
| Flood | Mar 13, 2003 | — |
| Flash Flood | Jul 30, 1998 | — |
| Flood | May 1, 1997 | $69,000 |
— = no damage estimate in the record. Source: NOAA Storm Events Database.
Flash Flood · Jun 6, 2023. Anomalous atmospheric moisture combined with slow moving thunderstorms caused copious amounts of rain and in some places flooding.
Flash Flood · Aug 1, 2021. Monsoonal subtropical moisture set the stage for thunderstorms to produce heavy rainfall across southwest Montana. North of this moisture plume, the Boulder 2700 fire burned down structures near Montana Highway 35 along the southeastern shore of Flathead Lake.
Flood · Mar 19, 2017. An ice jam on the Big Hole River caused water to back into properties in Silver Bow County.
Flash Flood · Aug 6, 2009. A strong low pressure system and associated cold front moved into the Northern Rockies, creating a favorable environment for strong hail producing thunderstorms and heavy rain. Flash flooding was reported in the city of Butte with this event as up to an inch of precipitation occurred in 30 to 45 minutes. Hail up to the size of baseballs and strong winds nearing 70 mph were also observed.
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 Silver Bow 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.