County annual report · FIPS 55055
2018 Jefferson County, WI Power Outage Report
In 2018, customers in Jefferson County, WI went without power for an average of 3.2 hours, a total of 110K customer-hours (Wisconsin average 1.7 hours). That ranks 18th worst of 71 Wisconsin counties and 1454th of 2,798 nationally.
Compared with WI, the US and 2017
Coverage line is EAGLE-I's share of Wisconsin customers tracked each year.
Biggest outages in Jefferson County, 2018
The 10 outage episodes with the most customers out at once. Times are UTC.
| # | Started (UTC) | Ended (UTC) | Duration | Peak out | Customer-hours |
|---|---|---|---|---|---|
| 1 | June 20, 2018 00:45 | June 20, 2018 05:45 | 5h | 5,472 | 22K |
| 2 | August 26, 2018 23:15 | August 28, 2018 01:30 | 1d 2h | 5,261 | 24K |
| 3 | April 13, 2018 10:00 | April 13, 2018 15:15 | 5h 15m | 2,653 | 3,324 |
| 4 | December 28, 2018 13:00 | December 28, 2018 14:15 | 1h 15m | 2,095 | 526 |
| 5 | July 5, 2018 18:30 | July 6, 2018 05:45 | 11h 15m | 1,859 | 4,747 |
| 6 | July 13, 2018 02:30 | July 13, 2018 05:00 | 2h 30m | 1,855 | 4,173 |
| 7 | October 10, 2018 16:15 | October 10, 2018 16:30 | 15m | 1,694 | 424 |
| 8 | July 1, 2018 15:00 | July 2, 2018 09:45 | 18h 45m | 1,658 | 2,233 |
| 9 | October 15, 2018 23:45 | October 16, 2018 04:45 | 5h | 1,437 | 2,215 |
| 10 | June 15, 2018 11:45 | June 15, 2018 17:00 | 5h 15m | 1,377 | 1,102 |
Outage episodes by size in 2018: 43 reached 100+ customers, 14 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 Jefferson County reported on EIA Form 861 for 2018, 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 |
|---|---|---|---|---|---|
| Wisconsin Electric Power Co | 2018 | 2.0 hrs | 0.73 | 70 min | 0.59 |
| Adams-Columbia Electric Coop | 2018 | 6.5 hrs | 0.91 | 50 min | 0.46 |
| Wisconsin Power & Light Co | - | - | - | - | - |
| Jefferson Utilities | - | - | - | - | - |
| Lake Mills Light & Water | - | - | - | - | - |
| Waterloo Light & Water Comm | - | - | - | - | - |
About this data
- Outage figures come from DOE/ORNL EAGLE-I, which records customers out by county every 15 minutes. EAGLE-I tracked about 83% of Wisconsin's customers in 2018; utilities it does not see are not counted.
- Hours per customer = outage customer-minutes ÷ 34,512 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. Jefferson County has data for 2015–2025.
Cite this report
MassOutage (massoutage.com), Jefferson County, WI annual power outage report, 2018, 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/2018/wisconsin/jefferson-county