Valley CountyPower Outage History
What this grade means
(How grades are calculated)Average — typical outage frequency and duration nationally. This county sits in the middle of the national distribution — its outage frequency and duration over the past 12 years are close to the nationwide median, neither notably better nor worse than most other US counties. A typical amount of backup-power preparedness is reasonable here.
Outages by year
Outages by month (seasonality)
Worst outage events on record
| Date | Duration | Customers affected | Cause |
|---|---|---|---|
| Jul 23, 2021 | 6 hrs | 3,217 (81%) | Drought |
| Jan 24, 2025 | 2 hrs | 3,214 (81%) | Winter Weather |
| Nov 5, 2021 | 7 hrs | 3,174 (80%) | Drought |
| Dec 26, 2025 | 3 hrs | 3,145 (79%) | Unnamed event |
| Mar 8, 2021 | 2 hrs | 2,890 (73%) | Drought |
Was There an Outage on a Specific Date?
Pick a date to see whether a power outage was recorded for Valley County, Montana that day.
Over the 7 years from 2019 to 2025, Valley County recorded 117 distinct power outage events, averaging 4.0 hours per event.
The single worst outage on record in Valley County started July 23, 2021 (Drought), lasting 6 hours and leaving up to 3,217 customers without power (81% of the county) at its peak.
June has historically been the worst month for outages in Valley County, with 20 events recorded during that month across the dataset.
Based on this history, Valley County earns a Reliability Grade of C, placing it in the 49th percentile nationally for grid reliability (higher percentile = more reliable).
Similar counties in Montana
Counties with the closest reliability grade and national percentile to Valley County.
| County | Grade | National percentile |
|---|---|---|
| Wheatland County | C | 48th |
| Judith Basin County | C | 49th |
| Sweet Grass County | C | 54th |
| Powell County | C | 55th |
| Missoula County | C | 42nd |
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 Valley County?
Between 2019 and 2025, Valley County recorded 117 outage events, averaging 4.0 hours each.
What is Valley County's reliability grade?
Valley County has a Reliability Grade of C, in the 49th national percentile.
What was the worst power outage in Valley County?
The worst outage on record started July 23, 2021 (Drought), lasting 6 hours and affecting up to 3,217 customers.