County annual report · FIPS 46135
2025 Yankton County, SD Power Outage Report
In 2025, customers in Yankton County, SD went without power for an average of 2.3 hours, a total of 27K customer-hours (South Dakota average 6.5 hours). That ranks 36th worst of 65 South Dakota counties and 2325th 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 Yankton 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 | February 18, 2025 09:45 | February 18, 2025 13:45 | 4h | 1,953 | 7,444 |
| 2 | March 15, 2025 11:15 | March 15, 2025 19:00 | 7h 45m | 1,433 | 3,154 |
| 3 | August 30, 2025 16:30 | August 30, 2025 17:30 | 1h | 1,310 | 1,310 |
| 4 | July 30, 2025 01:45 | July 30, 2025 06:30 | 4h 45m | 1,081 | 3,783 |
| 5 | June 28, 2025 04:30 | June 28, 2025 08:15 | 3h 45m | 864 | 3,024 |
| 6 | July 10, 2025 19:00 | July 11, 2025 05:15 | 10h 15m | 421 | 860 |
| 7 | May 31, 2025 01:45 | May 31, 2025 04:15 | 2h 30m | 323 | 808 |
| 8 | October 16, 2025 04:15 | October 16, 2025 12:15 | 8h | 170 | 1,360 |
| 9 | September 23, 2025 17:45 | September 23, 2025 22:15 | 4h 30m | 167 | 299 |
| 10 | February 27, 2025 15:45 | February 27, 2025 17:15 | 1h 30m | 151 | 227 |
Outage episodes by size in 2025: 15 reached 100+ customers, 4 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 Yankton 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 |
| Bon Homme Yankton El Assn, Inc | 2018 | 34 min | 0.32 | 34 min | 0.32 |
| WAPA-- Western Area Power Administration | - | - | - | - | - |
| Southeastern Electric Coop Inc - (SD) | - | - | - | - | - |
| Clay-Union Electric Corp | - | - | - | - | - |
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 ÷ 11,940 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. Yankton County has data for 2019–2025.
Cite this report
MassOutage (massoutage.com), Yankton 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/yankton-county