County annual report · FIPS 19079
2021 Hamilton County, IA Power Outage Report
In 2021, customers in Hamilton County, IA went without power for an average of 4.3 hours, a total of 39K customer-hours (Iowa average 2.7 hours). That ranks 35th worst of 99 Iowa counties and 1485th of 2,974 nationally.
Compared with IA, the US and 2020
Coverage line is EAGLE-I's share of Iowa customers tracked each year.
Biggest outages in Hamilton County, 2021
The 10 outage episodes with the most customers out at once. Times are UTC.
| # | Started (UTC) | Ended (UTC) | Duration | Peak out | Customer-hours |
|---|---|---|---|---|---|
| 1 | December 16, 2021 00:00 | December 19, 2021 00:15 | 3d | 1,621 | 25K |
| 2 | December 10, 2021 22:45 | December 11, 2021 15:30 | 16h 45m | 1,317 | 8,692 |
| 3 | August 8, 2021 06:45 | August 8, 2021 10:30 | 3h 45m | 938 | 595 |
| 4 | February 16, 2021 13:45 | February 16, 2021 17:45 | 4h | 647 | 827 |
| 5 | September 30, 2021 10:30 | September 30, 2021 12:00 | 1h 30m | 365 | 369 |
| 6 | June 13, 2021 06:15 | June 13, 2021 08:30 | 2h 15m | 281 | 492 |
| 7 | May 16, 2021 21:45 | May 16, 2021 23:45 | 2h | 201 | 202 |
| 8 | January 30, 2021 22:00 | January 31, 2021 01:15 | 3h 15m | 171 | 367 |
| 9 | September 3, 2021 00:45 | September 3, 2021 01:30 | 45m | 165 | 102 |
| 10 | September 30, 2021 13:15 | September 30, 2021 15:30 | 2h 15m | 130 | 269 |
Outage episodes by size in 2021: 11 reached 100+ customers, 2 reached 1,000+ customers, 0 reached 10,000+ customers.
Utility reliability filed with the EIA
SAIDI (average outage time per customer) and SAIFI (average interruptions per customer) that utilities serving Hamilton County reported on EIA Form 861 for 2021, or their most recent earlier filing. Utility-wide figures, not county-specific.
| Utility | EIA year | SAIDI | SAIFI | SAIDI excl. major events | SAIFI excl. major events |
|---|---|---|---|---|---|
| MidAmerican Energy Co | 2021 | 1.9 hrs | 1.04 | 75 min | 0.74 |
| Interstate Power and Light Co | - | - | - | - | - |
| Alliant Energy (Interstate Power & Light) | - | - | - | - | - |
| Midland Power Coop | - | - | - | - | - |
| Prairie Energy Coop | - | - | - | - | - |
| City of Story City - (IA) | - | - | - | - | - |
| Cass Electric Coop | - | - | - | - | - |
| City of Stratford - (IA) | - | - | - | - | - |
| City of Ellsworth - (IA) | - | - | - | - | - |
| City of Stanhope - (IA) | - | - | - | - | - |
| City of Webster City - (IA) | - | - | - | - | - |
| Pleasant Hill Community Line | - | - | - | - | - |
About this data
- Outage figures come from DOE/ORNL EAGLE-I, which records customers out by county every 15 minutes. EAGLE-I tracked about 91% of Iowa's customers in 2021; utilities it does not see are not counted.
- Hours per customer = outage customer-minutes ÷ 9,205 customers (ORNL modeled county customer count), including major storm days. It is comparable across counties but is not the SAIDI a utility files.
- An outage event is a continuous stretch with customers out; counts at 100, 1,000 and 10,000+ use its peak.
- Years loaded: 2015–2025. Hamilton County has data for 2015–2025.
Cite this report
MassOutage (massoutage.com), Hamilton County, IA annual power outage report, 2021, data as of Oct 3, 2026 02:41 UTC, sources: DOE EAGLE-I (https://eagle-i.doe.gov/); EAGLE-I modeled customer counts (MCC) (https://figshare.com/); EIA Form 861 (utility reliability) (https://www.eia.gov/electricity/data/eia861/). https://massoutage.com/reports/2021/iowa/hamilton-county