2 flood insurance claims·$63,440 paid·2 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 Cassia County, Idaho. 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.
Flash flooding from summer thunderstorms and snowmelt-driven events dominates the flood profile of Cassia County. Over the last 30 years, the NOAA Storm Events Database recorded 22 flash flood events resulting in 1 death, alongside 3 general flood events.
Significant flood events occurred in January and February 2017, when extreme winter snowfall followed by rain and above-normal temperatures caused an emergency declaration in Cassia County and extensive flooding in low-lying areas that persisted through March. Additionally, a localized flash flood event occurred south of Oakley on September 3, 2013.
National Flood Insurance Program records indicate minimal historical claims, with one claim each in Zone A (averaging a $6,751 payout) and Zone X-unshaded (averaging a $56,689 payout), both recording an average water depth of 0 inches. Property owners located in low-lying areas, near mountain snowmelt runoff paths, and in designated flood zones should pay the closest attention to flood risks.
Summary written from NOAA storm reports and NFIP claims for this county. Not a prediction.
4 NOAA storm reports from Cassia County describe what happened, in the words of the forecasters who covered it. Read the Idaho flood stories →
5 federal disaster declarations since 1964, 2 of them floods, coastal storms or hurricanes.
| Disaster | Began |
|---|---|
| Severe Winter Storms And Flooding | Feb 5, 2017 |
| Hurricane Katrina | Aug 29, 2005 |
| Heavy Rains & Flooding | Dec 31, 1964 |
Weather and water disasters only; most recent first. Source: OpenFEMA Disaster Declarations.
25 since 1996: 22 flash floods and 3 river or area floods.
| Event | Date | Damage |
|---|---|---|
| Flash Flood | May 24, 2023 | — |
| Flash Flood | Jul 31, 2021 | — |
| Flash Flood | Jul 30, 2021 | — |
| Flood | Jan 8, 2017 | — |
| Flood | Feb 4, 2017 | $5.2M |
| Flood | Mar 1, 2017 | $175,000 |
| Flash Flood | Sep 3, 2013 | $6,000 |
| Flash Flood | Sep 2, 2013 | $4,000 |
— = no damage estimate in the record. Source: NOAA Storm Events Database.
Flash Flood · May 24, 2023. Widespread large hail was reported in parts of southeast Idaho.
Flash Flood · Jul 31, 2021. Sustained monsoonal flow brought more flooding to southeast Idaho on July 31st.
Flash Flood · Jul 30, 2021. Sustained monsoonal flow brought heavy rains and several areas with flash flooding.
Flood · Jan 8, 2017. A long dawn out atmospheric river event brought a variety of impacts to southeast Idaho including extremely heavy mountain snow, valley snow then rain on snow leading to flooding and roads covered with ice in the Snake River Plain, and many mountain avalanches. Many roads were closed for extended periods due to the heavy snow and avalanches. Custer County was declared a disaster area due to the prodigious snow…
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 Cassia 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.