County annual report · FIPS 19103
2018 Johnson County, IA Power Outage Report
In 2018, customers in Johnson County, IA went without power for an average of 1.9 hours, a total of 145K customer-hours (Iowa average 2.2 hours). That ranks 59th worst of 99 Iowa counties and 1918th of 2,798 nationally.
Compared with IA, the US and 2017
Coverage line is EAGLE-I's share of Iowa customers tracked each year.
Biggest outages in Johnson 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 | November 5, 2018 21:30 | November 6, 2018 13:00 | 15h 30m | 12,865 | 5,641 |
| 2 | June 9, 2018 11:00 | June 9, 2018 18:00 | 7h | 10,998 | 7,962 |
| 3 | August 28, 2018 16:00 | August 30, 2018 03:30 | 1d 11h | 8,625 | 14K |
| 4 | August 12, 2018 08:00 | August 12, 2018 17:15 | 9h 15m | 3,258 | 7,616 |
| 5 | February 18, 2018 17:30 | February 18, 2018 20:45 | 3h 15m | 3,041 | 4,983 |
| 6 | January 21, 2018 02:00 | January 21, 2018 03:00 | 1h | 2,979 | 1,988 |
| 7 | November 23, 2018 07:30 | November 23, 2018 09:15 | 1h 45m | 2,670 | 4,005 |
| 8 | October 10, 2018 00:00 | October 10, 2018 02:45 | 2h 45m | 2,495 | 640 |
| 9 | June 22, 2018 17:30 | June 22, 2018 19:30 | 2h | 2,471 | 623 |
| 10 | May 16, 2018 22:00 | May 17, 2018 01:30 | 3h 30m | 2,352 | 2,673 |
Outage episodes by size in 2018: 90 reached 100+ customers, 26 reached 1,000+ customers, 2 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 Johnson 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 |
|---|---|---|---|---|---|
| MidAmerican Energy Co | 2018 | 1.9 hrs | 1.18 | 75 min | 0.96 |
| Eastern Iowa Light & Power Coop | 2018 | 1.9 hrs | 0.92 | 1.7 hrs | 0.85 |
| T I P Rural Electric Coop | 2018 | 2.5 hrs | 1.33 | 2.5 hrs | 1.33 |
| Linn County REC | 2018 | 2.6 hrs | 1.13 | 2.6 hrs | 1.13 |
| Farmers Electric Coop - (IA) | 2018 | 77 min | 2.30 | 77 min | 2.30 |
| Interstate Power and Light Co | - | - | - | - | - |
| Alliant Energy (Interstate Power & Light) | - | - | - | - | - |
| East-Central Iowa Rural Elec Coop | - | - | - | - | - |
About this data
- Outage figures come from DOE/ORNL EAGLE-I, which records customers out by county every 15 minutes. EAGLE-I tracked about 89% of Iowa's customers in 2018; utilities it does not see are not counted.
- Hours per customer = outage customer-minutes ÷ 77,769 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. Johnson County has data for 2015–2025.
Cite this report
MassOutage (massoutage.com), Johnson County, IA 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/iowa/johnson-county