County annual report · FIPS 30057
2018 Madison County, MT Power Outage Report
In 2018, customers in Madison County, MT went without power for an average of 0.0 hours, a total of 21 customer-hours (Montana average 1.9 hours). That ranks 19th worst of 20 Montana counties and 2765th of 2,798 nationally.
Compared with MT, the US
Coverage line is EAGLE-I's share of Montana customers tracked each year.
Biggest outages in Madison County, 2018
The 4 outage episodes with the most customers out at once. Times are UTC.
| # | Started (UTC) | Ended (UTC) | Duration | Peak out | Customer-hours |
|---|---|---|---|---|---|
| 1 | January 10, 2018 17:30 | January 10, 2018 17:45 | 15m | 5 | 1 |
| 2 | July 30, 2018 14:30 | July 30, 2018 15:45 | 1h 15m | 5 | 6 |
| 3 | August 2, 2018 14:15 | August 2, 2018 16:00 | 1h 45m | 5 | 9 |
| 4 | August 14, 2018 14:15 | August 14, 2018 15:15 | 1h | 5 | 5 |
Outage episodes by size in 2018: 0 reached 100+ customers, 0 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 Madison 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 |
|---|---|---|---|---|---|
| NorthWestern Energy LLC - (MT) | 2018 | 1.7 hrs | 1.08 | 1.7 hrs | 1.08 |
| Vigilante 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 16% of Montana's customers in 2018; utilities it does not see are not counted.
- Hours per customer = outage customer-minutes ÷ 6,199 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. Madison County has data for 2018–2025.
Cite this report
MassOutage (massoutage.com), Madison County, MT 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/montana/madison-county