County annual report · FIPS 46127
2021 Union County, SD Power Outage Report
In 2021, customers in Union County, SD went without power for an average of 2.6 hours, a total of 8,705 customer-hours (South Dakota average 3.4 hours). That ranks 33rd worst of 61 South Dakota counties and 2004th of 2,974 nationally.
Compared with SD, the US and 2020
Coverage line is EAGLE-I's share of South Dakota customers tracked each year.
Biggest outages in Union County, 2021
The 10 outage episodes with the most customers out at once. Times are UTC.
| # | Started (UTC) | Ended (UTC) | Duration | Peak out | Customer-hours |
|---|---|---|---|---|---|
| 1 | October 3, 2021 15:45 | October 3, 2021 17:00 | 1h 15m | 1,843 | 1,755 |
| 2 | May 19, 2021 20:45 | May 19, 2021 21:30 | 45m | 883 | 662 |
| 3 | December 16, 2021 01:45 | December 16, 2021 11:45 | 10h | 488 | 850 |
| 4 | October 27, 2021 12:30 | October 27, 2021 14:15 | 1h 45m | 336 | 259 |
| 5 | October 23, 2021 15:15 | October 23, 2021 19:45 | 4h 30m | 193 | 70 |
| 6 | August 1, 2021 07:45 | August 2, 2021 13:30 | 1d 5h | 106 | 647 |
| 7 | July 22, 2021 12:00 | July 24, 2021 21:00 | 2d 9h | 88 | 130 |
| 8 | September 22, 2021 16:15 | September 22, 2021 19:00 | 2h 45m | 85 | 87 |
| 9 | November 11, 2021 15:00 | November 11, 2021 17:15 | 2h 15m | 68 | 58 |
| 10 | August 27, 2021 06:15 | August 27, 2021 14:00 | 7h 45m | 67 | 155 |
Outage episodes by size in 2021: 6 reached 100+ customers, 1 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 2021, 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 | 2021 | 1.9 hrs | 1.04 | 75 min | 0.74 |
| 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 79% of South Dakota's customers in 2021; 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, 2021, 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/2021/south-dakota/union-county