County annual report · FIPS 46127
2025 Union County, SD Power Outage Report
In 2025, customers in Union County, SD went without power for an average of 7.3 hours, a total of 24K customer-hours (South Dakota average 6.5 hours). That ranks 16th worst of 65 South Dakota counties and 1101st 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 Union 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 | July 29, 2025 02:30 | August 6, 2025 14:00 | 8d 11h | 650 | 15K |
| 2 | June 2, 2025 22:30 | June 3, 2025 00:00 | 1h 30m | 560 | 476 |
| 3 | May 19, 2025 11:00 | May 19, 2025 20:00 | 9h | 542 | 935 |
| 4 | June 3, 2025 00:45 | June 3, 2025 05:45 | 5h | 406 | 1,758 |
| 5 | October 19, 2025 16:15 | October 22, 2025 11:15 | 2d 19h | 240 | 664 |
| 6 | June 22, 2025 08:45 | June 22, 2025 14:15 | 5h 30m | 223 | 296 |
| 7 | July 16, 2025 02:15 | July 16, 2025 09:15 | 7h | 223 | 940 |
| 8 | March 19, 2025 13:45 | March 20, 2025 01:15 | 11h 30m | 187 | 571 |
| 9 | June 21, 2025 23:30 | June 22, 2025 01:45 | 2h 15m | 182 | 245 |
| 10 | March 7, 2025 02:15 | March 7, 2025 05:15 | 3h | 88 | 262 |
Outage episodes by size in 2025: 9 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 Union 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 |
|---|---|---|---|---|---|
| MidAmerican Energy Co | 2024 | 5.5 hrs | 1.42 | 1.7 hrs | 0.94 |
| WAPA-- Western Area Power Administration | - | - | - | - | - |
| Southeastern Electric Coop Inc - (SD) | - | - | - | - | - |
| Clay-Union Electric Corp | - | - | - | - | - |
| City of Beresford | - | - | - | - | - |
| City of Elk Point | - | - | - | - | - |
| Union County 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 ÷ 3,359 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. Union County has data for 2015–2017, 2019–2025.
Cite this report
MassOutage (massoutage.com), Union 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/union-county