Mariposa County Power Outage History
2018–2025 · California
Bottom 20% least reliable nationally — frequent and/or long outages. How grades are calculated
Outages by year
Outages by month (seasonality)
Worst outage events on record
| Date | Duration | Customers affected | Cause |
|---|---|---|---|
| Nov 3, 2021 | 4 hrs | 10,893 (100%) | Drought |
| Feb 24, 2023 | 220 hrs | 10,887 (100%) | Frost/Freeze |
| Mar 10, 2021 | 4 hrs | 10,290 (94%) | Unnamed event |
| Oct 4, 2020 | 9 hrs | 10,268 (94%) | Unnamed event |
| Feb 16, 2019 | 70 hrs | 10,236 (94%) | Unnamed event |
Over the 8 years from 2018 to 2025, Mariposa County recorded 964 distinct power outage events, averaging 5.9 hours per event.
The single worst outage on record in Mariposa County started November 3, 2021 (Drought), lasting 4 hours and leaving up to 10,893 customers without power (100% of the county) at its peak.
October has historically been the worst month for outages in Mariposa County, with 146 events recorded during that month across the dataset.
Based on this history, Mariposa County earns a Reliability Grade of F, placing it in the 1st percentile nationally for grid reliability (higher percentile = more reliable).
Sized for Mariposa County's outage profile
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Similar counties in California
Counties with the closest reliability grade and national percentile to Mariposa County.
| County | Grade | National percentile |
|---|---|---|
| Plumas County | F | 1st |
| Calaveras County | F | 1st |
| Amador County | F | 1st |
| Tuolumne County | F | 1st |
| Butte County | F | 1st |
FAQ
How often does power go out in Mariposa County?
Between 2018 and 2025, Mariposa County recorded 964 outage events, averaging 5.9 hours each.
What is Mariposa County's reliability grade?
Mariposa County has a Reliability Grade of F, in the 1st national percentile.
What was the worst power outage in Mariposa County?
The worst outage on record started November 3, 2021 (Drought), lasting 4 hours and affecting up to 10,893 customers.