Cassia CountyPower Outage History
What this grade means
Top 20% most reliable nationally — infrequent, short outages. This county ranks in the most reliable fifth of all US counties in our dataset, based on 12 years of real DOE outage records: outages happen less often here, and when they do occur they tend to be resolved quickly compared to the rest of the country. Baseline outage risk is low, though a severe local storm can still occasionally cause a longer-than-usual outage regardless of the long-term track record.
Outages by year
Outages by month (seasonality)
Worst outage events on record
| Date | Duration | Customers affected | Cause |
|---|---|---|---|
| Jan 9, 2024 | 4 hrs | 4,987 (33%) | Winter Storm |
| Jul 18, 2021 | 2 hrs | 4,268 (29%) | Wildfire |
| Aug 18, 2024 | 4 hrs | 4,239 (28%) | Thunderstorm Wind |
| Dec 14, 2019 | <1 hr | 4,180 (28%) | Heavy Snow |
| Aug 20, 2019 | 2 hrs | 3,714 (25%) | Unnamed event |
Was There an Outage on a Specific Date?
Pick a date to see whether a power outage was recorded for Cassia County, Idaho that day.
Over the 11 years from 2015 to 2025, Cassia County recorded 163 distinct power outage events, averaging 1.8 hours per event.
The single worst outage on record in Cassia County started January 9, 2024 (Winter Storm), lasting 4 hours and leaving up to 4,987 customers without power (33% of the county) at its peak.
August has historically been the worst month for outages in Cassia County, with 24 events recorded during that month across the dataset.
Based on this history, Cassia County earns a Reliability Grade of A, placing it in the 90th percentile nationally for grid reliability (higher percentile = more reliable).
Similar counties in Idaho
Counties with the closest reliability grade and national percentile to Cassia County.
| County | Grade | National percentile |
|---|---|---|
| Ada County | A | 92nd |
| Camas County | A | 92nd |
| Canyon County | A | 88th |
| Minidoka County | A | 95th |
| Bonneville County | A | 85th |
Most reliable counties nationally
The top 3 counties nationally by reliability grade and percentile.
| County | State | Grade | National percentile |
|---|---|---|---|
| Clay County | South Dakota | A | 100th |
| Clearwater County | Minnesota | A | 99th |
| Limestone County | Alabama | A | 99th |
Least reliable counties nationally
The bottom 3 counties nationally by reliability grade and percentile.
| County | State | Grade | National percentile |
|---|---|---|---|
| Clay County | West Virginia | F | 0th |
| Lincoln County | West Virginia | F | 0th |
| Cameron Parish | Louisiana | F | 0th |
FAQ
How often does power go out in Cassia County?
Between 2015 and 2025, Cassia County recorded 163 outage events, averaging 1.8 hours each.
What is Cassia County's reliability grade?
Cassia County has a Reliability Grade of A, in the 90th national percentile.
What was the worst power outage in Cassia County?
The worst outage on record started January 9, 2024 (Winter Storm), lasting 4 hours and affecting up to 4,987 customers.