County annual report · FIPS 30049
2020 Lewis and Clark County, MT Power Outage Report
In 2020, customers in Lewis and Clark County, MT went without power for an average of 4.0 hours, a total of 131K customer-hours (Montana average 5.6 hours). That ranks 32nd worst of 50 Montana counties and 1611th of 3,019 nationally.
Compared with MT, the US and 2019
Coverage line is EAGLE-I's share of Montana customers tracked each year.
Biggest outages in Lewis and Clark County, 2020
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 3, 2020 16:30 | June 3, 2020 20:45 | 4h 15m | 8,404 | 12K |
| 2 | September 17, 2020 18:45 | September 17, 2020 20:30 | 1h 45m | 4,488 | 4,777 |
| 3 | October 14, 2020 13:45 | October 15, 2020 04:00 | 14h 15m | 3,862 | 9,001 |
| 4 | July 31, 2020 16:15 | July 31, 2020 20:00 | 3h 45m | 3,851 | 5,777 |
| 5 | July 11, 2020 16:30 | July 12, 2020 02:30 | 10h | 2,333 | 11K |
| 6 | July 14, 2020 23:00 | July 15, 2020 02:30 | 3h 30m | 2,319 | 5,805 |
| 7 | August 4, 2020 15:15 | August 4, 2020 23:45 | 8h 30m | 2,186 | 6,017 |
| 8 | August 20, 2020 10:00 | August 20, 2020 13:30 | 3h 30m | 1,718 | 5,980 |
| 9 | August 1, 2020 13:45 | August 1, 2020 18:45 | 5h | 1,708 | 6,829 |
| 10 | July 3, 2020 19:00 | July 7, 2020 00:15 | 3d 5h | 1,705 | 4,173 |
Outage episodes by size in 2020: 46 reached 100+ customers, 14 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 Lewis and Clark County reported on EIA Form 861 for 2020, 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) | 2020 | 2.8 hrs | 1.13 | 2.0 hrs | 1.02 |
| WAPA-- Western Area Power Administration | - | - | - | - | - |
| Vigilante Electric Coop, Inc | - | - | - | - | - |
| Sun River 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 76% of Montana's customers in 2020; utilities it does not see are not counted.
- Hours per customer = outage customer-minutes ÷ 32,887 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. Lewis and Clark County has data for 2019–2025.
Cite this report
MassOutage (massoutage.com), Lewis and Clark County, MT annual power outage report, 2020, 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/2020/montana/lewis-and-clark-county