County annual report · FIPS 46057
2021 Hamlin County, SD Power Outage Report
In 2021, customers in Hamlin County, SD went without power for an average of 24.4 hours, a total of 53K customer-hours (South Dakota average 3.4 hours). That ranks 4th worst of 61 South Dakota counties and 347th 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 Hamlin 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 | August 26, 2021 15:00 | August 27, 2021 02:45 | 11h 45m | 741 | 2,121 |
| 2 | January 6, 2021 13:15 | January 6, 2021 14:45 | 1h 30m | 675 | 1,008 |
| 3 | July 17, 2021 23:30 | July 19, 2021 22:00 | 1d 22h | 666 | 25K |
| 4 | July 28, 2021 06:15 | July 28, 2021 15:30 | 9h 15m | 489 | 3,705 |
| 5 | October 18, 2021 20:00 | October 18, 2021 22:15 | 2h 15m | 470 | 728 |
| 6 | October 4, 2021 13:30 | October 4, 2021 15:45 | 2h 15m | 456 | 1,026 |
| 7 | March 14, 2021 05:30 | March 15, 2021 14:45 | 1d 9h | 378 | 1,144 |
| 8 | July 14, 2021 12:45 | July 14, 2021 16:15 | 3h 30m | 337 | 203 |
| 9 | August 11, 2021 22:30 | August 12, 2021 15:30 | 17h | 336 | 4,492 |
| 10 | September 19, 2021 23:00 | September 20, 2021 00:00 | 1h | 193 | 193 |
Outage episodes by size in 2021: 16 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 Hamlin 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 |
|---|---|---|---|---|---|
| Otter Tail Power Co | 2021 | 86 min | 1.13 | 74 min | 1.09 |
| NorthWestern Energy - (SD) | 2021 | 1.5 hrs | 0.95 | 81 min | 0.83 |
| Sioux Valley SW Elec Coop | 2021 | 1.8 hrs | 1.08 | 1.5 hrs | 0.93 |
| 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 | - | - | - | - | - |
| City of Bryant - (SD) | - | - | - | - | - |
| City of Estelline - (SD) | - | - | - | - | - |
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 ÷ 2,187 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. Hamlin County has data for 2018–2025.
Cite this report
MassOutage (massoutage.com), Hamlin 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/hamlin-county