County annual report · FIPS 55133
2019 Waukesha County, WI Power Outage Report
In 2019, customers in Waukesha County, WI went without power for an average of 6.1 hours, a total of 878K customer-hours (Wisconsin average 4.4 hours). That ranks 20th worst of 71 Wisconsin counties and 899th of 2,945 nationally.
Compared with WI, the US and 2018
Coverage line is EAGLE-I's share of Wisconsin customers tracked each year.
Biggest outages in Waukesha County, 2019
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 30, 2019 10:15 | July 1, 2019 22:00 | 1d 11h | 21,890 | 133K |
| 2 | June 27, 2019 20:30 | June 30, 2019 06:15 | 2d 9h | 19,874 | 280K |
| 3 | July 2, 2019 12:30 | July 4, 2019 07:15 | 1d 18h | 11,593 | 108K |
| 4 | November 14, 2019 15:45 | November 14, 2019 23:00 | 7h 15m | 9,493 | 3,146 |
| 5 | May 19, 2019 17:30 | May 20, 2019 06:30 | 13h | 5,409 | 17K |
| 6 | September 12, 2019 00:30 | September 14, 2019 10:15 | 2d 9h | 5,316 | 19K |
| 7 | May 30, 2019 19:45 | May 31, 2019 04:30 | 8h 45m | 5,000 | 1,327 |
| 8 | February 24, 2019 12:45 | February 25, 2019 07:15 | 18h 30m | 3,968 | 15K |
| 9 | February 14, 2019 12:30 | February 14, 2019 22:45 | 10h 15m | 3,812 | 6,713 |
| 10 | October 25, 2019 16:45 | October 26, 2019 01:30 | 8h 45m | 3,780 | 958 |
Outage episodes by size in 2019: 116 reached 100+ customers, 43 reached 1,000+ customers, 3 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 Waukesha County reported on EIA Form 861 for 2019, 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 |
| Oconomowoc Utilities | - | - | - | - | - |
About this data
- Outage figures come from DOE/ORNL EAGLE-I, which records customers out by county every 15 minutes. EAGLE-I tracked about 84% of Wisconsin's customers in 2019; utilities it does not see are not counted.
- Hours per customer = outage customer-minutes ÷ 143,177 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. Waukesha County has data for 2015–2025.
Cite this report
MassOutage (massoutage.com), Waukesha County, WI annual power outage report, 2019, 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/2019/wisconsin/waukesha-county