County annual report · FIPS 30017
2023 Custer County, MT Power Outage Report
In 2023, customers in Custer County, MT went without power for an average of 0.6 hours, a total of 4,348 customer-hours (Montana average 1.8 hours). That ranks 41st worst of 50 Montana counties and 2789th of 2,977 nationally.
Compared with MT, the US and 2022
Coverage line is EAGLE-I's share of Montana customers tracked each year.
Biggest outages in Custer County, 2023
The 10 outage episodes with the most customers out at once. Times are UTC.
| # | Started (UTC) | Ended (UTC) | Duration | Peak out | Customer-hours |
|---|---|---|---|---|---|
| 1 | July 11, 2023 22:15 | July 12, 2023 01:15 | 3h | 2,691 | 2,738 |
| 2 | June 19, 2023 00:15 | June 19, 2023 02:00 | 1h 45m | 671 | 526 |
| 3 | August 31, 2023 00:45 | August 31, 2023 04:15 | 3h 30m | 309 | 185 |
| 4 | July 13, 2023 13:45 | July 13, 2023 14:30 | 45m | 111 | 82 |
| 5 | April 28, 2023 23:45 | April 29, 2023 00:45 | 1h | 50 | 50 |
| 6 | July 3, 2023 12:15 | July 3, 2023 12:45 | 30m | 48 | 13 |
| 7 | May 22, 2023 19:15 | May 22, 2023 19:45 | 30m | 43 | 12 |
| 8 | August 29, 2023 08:00 | August 29, 2023 09:15 | 1h 15m | 41 | 51 |
| 9 | September 1, 2023 13:45 | September 1, 2023 14:00 | 15m | 39 | 10 |
| 10 | May 8, 2023 23:15 | May 8, 2023 23:30 | 15m | 38 | 10 |
Outage episodes by size in 2023: 4 reached 100+ customers, 1 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 Custer County reported on EIA Form 861 for 2023, 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 |
|---|---|---|---|---|---|
| Mid-Yellowstone Elec Coop, Inc | 2018 | 4.5 hrs | 3.82 | 4.5 hrs | 3.82 |
| WAPA-- Western Area Power Administration | - | - | - | - | - |
| Montana-Dakota Utilities Co | - | - | - | - | - |
| McCone Electric Coop Inc | - | - | - | - | - |
| Tongue River Electric Coop Inc | - | - | - | - | - |
| Southeast Electric Coop, Inc | - | - | - | - | - |
About this data
- Outage figures come from DOE/ORNL EAGLE-I, which records customers out by county every 15 minutes. EAGLE-I tracked about n/a of Montana's customers in 2023; utilities it does not see are not counted.
- Hours per customer = outage customer-minutes ÷ 6,942 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. Custer County has data for 2017–2025.
Cite this report
MassOutage (massoutage.com), Custer County, MT annual power outage report, 2023, 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/2023/montana/custer-county