County annual report · FIPS 30017
2017 Custer County, MT Power Outage Report
In 2017, customers in Custer County, MT went without power for an average of 1.7 hours, a total of 12K customer-hours (Montana average 2.7 hours). That ranks 7th worst of 19 Montana counties and 1759th of 2,786 nationally.
Compared with MT, the US
Coverage line is EAGLE-I's share of Montana customers tracked each year.
Biggest outages in Custer County, 2017
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 7, 2017 08:30 | November 7, 2017 09:45 | 1h 15m | 4,342 | 1,101 |
| 2 | April 13, 2017 00:15 | April 13, 2017 17:15 | 17h | 4,145 | 1,434 |
| 3 | October 1, 2017 16:00 | October 2, 2017 05:15 | 13h 15m | 1,092 | 610 |
| 4 | June 13, 2017 03:30 | June 13, 2017 12:45 | 9h 15m | 878 | 2,282 |
| 5 | July 25, 2017 10:30 | July 25, 2017 13:15 | 2h 45m | 646 | 981 |
| 6 | July 10, 2017 23:45 | July 11, 2017 15:00 | 15h 15m | 517 | 1,569 |
| 7 | September 15, 2017 01:30 | September 15, 2017 16:00 | 14h 30m | 372 | 593 |
| 8 | June 26, 2017 22:30 | July 6, 2017 22:15 | 9d 23h | 346 | 665 |
| 9 | August 21, 2017 13:00 | August 21, 2017 13:30 | 30m | 112 | 29 |
| 10 | October 14, 2017 23:00 | October 15, 2017 00:00 | 1h | 50 | 50 |
Outage episodes by size in 2017: 9 reached 100+ customers, 3 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 2017, 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 | 2017 | 4.6 hrs | 2.65 | 4.6 hrs | 2.65 |
| 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 2017; 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, 2017, 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/2017/montana/custer-county