Plymouth County Power Outage History
2015–2025 · Iowa
Top 20% most reliable nationally — infrequent, short outages. How grades are calculated
Outages by year
Outages by month (seasonality)
Worst outage events on record
| Date | Duration | Customers affected | Cause |
|---|---|---|---|
| Jun 18, 2016 | 37 hrs | 2,232 (18%) | Excessive Heat |
| Jun 29, 2025 | 7 hrs | 2,099 (17%) | Excessive Heat |
| Jul 30, 2024 | 16 hrs | 1,462 (12%) | Thunderstorm Wind |
| Dec 15, 2021 | 8 hrs | 1,387 (11%) | Winter Weather |
| Mar 19, 2025 | 3 hrs | 1,127 (9%) | Drought |
Over the 11 years from 2015 to 2025, Plymouth County recorded 324 distinct power outage events, averaging 2.0 hours per event.
The single worst outage on record in Plymouth County started June 18, 2016 (Excessive Heat), lasting 37 hours and leaving up to 2,232 customers without power (18% of the county) at its peak.
July has historically been the worst month for outages in Plymouth County, with 44 events recorded during that month across the dataset.
Based on this history, Plymouth County earns a Reliability Grade of A, placing it in the 88th percentile nationally for grid reliability (higher percentile = more reliable).
Sized for Plymouth County's outage profile
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Similar counties in Iowa
Counties with the closest reliability grade and national percentile to Plymouth County.
| County | Grade | National percentile |
|---|---|---|
| Osceola County | A | 88th |
| Cherokee County | A | 87th |
| Union County | A | 87th |
| Jackson County | A | 87th |
| Black Hawk County | A | 88th |
FAQ
How often does power go out in Plymouth County?
Between 2015 and 2025, Plymouth County recorded 324 outage events, averaging 2.0 hours each.
What is Plymouth County's reliability grade?
Plymouth County has a Reliability Grade of A, in the 88th national percentile.
What was the worst power outage in Plymouth County?
The worst outage on record started June 18, 2016 (Excessive Heat), lasting 37 hours and affecting up to 2,232 customers.