County annual report · FIPS 46025
2025 Clark County, SD Power Outage Report
In 2025, customers in Clark County, SD went without power for an average of 7.8 hours, a total of 12K customer-hours (South Dakota average 6.5 hours). That ranks 14th worst of 65 South Dakota counties and 1039th of 3,000 nationally.
Compared with SD, the US and 2024
Coverage line is EAGLE-I's share of South Dakota customers tracked each year.
Biggest outages in Clark County, 2025
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 11, 2025 14:30 | June 11, 2025 17:00 | 2h 30m | 1,953 | 3,110 |
| 2 | April 14, 2025 22:15 | April 15, 2025 00:00 | 1h 45m | 1,339 | 1,179 |
| 3 | December 10, 2025 04:45 | December 10, 2025 08:15 | 3h 30m | 1,283 | 2,886 |
| 4 | December 18, 2025 05:30 | December 18, 2025 08:15 | 2h 45m | 630 | 1,106 |
| 5 | June 17, 2025 15:00 | June 17, 2025 15:30 | 30m | 364 | 91 |
| 6 | June 22, 2025 23:00 | June 23, 2025 03:15 | 4h 15m | 364 | 785 |
| 7 | December 25, 2025 18:00 | December 25, 2025 19:30 | 1h 30m | 309 | 464 |
| 8 | May 22, 2025 02:15 | May 22, 2025 02:30 | 15m | 87 | 22 |
| 9 | September 10, 2025 15:00 | September 10, 2025 19:15 | 4h 15m | 61 | 196 |
| 10 | September 2, 2025 18:00 | September 3, 2025 00:45 | 6h 45m | 58 | 334 |
Outage episodes by size in 2025: 7 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 Clark County reported on EIA Form 861 for 2025, 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 - (SD) | 2024 | 76 min | 0.70 | 66 min | 0.65 |
| Northern Electric Coop, Inc | 2024 | 50 min | 0.67 | 50 min | 0.67 |
| H-D Electric Coop Inc | 2018 | 2.6 hrs | 1.52 | 1.6 hrs | 1.14 |
| WAPA-- Western Area Power Administration | - | - | - | - | - |
| Codington-Clark Elec Coop, Inc | - | - | - | - | - |
| Kingsbury 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 South Dakota's customers in 2025; utilities it does not see are not counted.
- Hours per customer = outage customer-minutes ÷ 1,587 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. Clark County has data for 2019–2025.
Cite this report
MassOutage (massoutage.com), Clark County, SD annual power outage report, 2025, 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/2025/south-dakota/clark-county