County annual report · FIPS 46037
2023 Day County, SD Power Outage Report
In 2023, customers in Day County, SD went without power for an average of 29.2 hours, a total of 118K customer-hours (South Dakota average 2.3 hours). That ranks 2nd worst of 61 South Dakota counties and 249th of 2,977 nationally.
Compared with SD, the US and 2022
Coverage line is EAGLE-I's share of South Dakota customers tracked each year.
Biggest outages in Day County, 2023
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 23, 2023 15:15 | October 31, 2023 13:15 | 7d 22h | 1,032 | 1,224 |
| 2 | March 31, 2023 22:15 | April 1, 2023 17:30 | 19h 15m | 1,027 | 10K |
| 3 | October 6, 2023 00:30 | October 6, 2023 02:30 | 2h | 673 | 1,346 |
| 4 | June 5, 2023 19:45 | June 5, 2023 22:15 | 2h 30m | 586 | 1,326 |
| 5 | June 12, 2023 23:00 | June 13, 2023 05:00 | 6h | 551 | 1,517 |
| 6 | July 31, 2023 15:00 | August 1, 2023 21:15 | 1d 6h | 539 | 2,705 |
| 7 | August 3, 2023 20:00 | August 9, 2023 16:15 | 5d 20h | 410 | 44K |
| 8 | June 26, 2023 15:00 | June 29, 2023 17:15 | 3d 2h | 384 | 1,284 |
| 9 | July 28, 2023 15:45 | July 30, 2023 23:15 | 2d 7h | 316 | 4,622 |
| 10 | June 30, 2023 14:45 | July 5, 2023 17:15 | 5d 2h | 284 | 33K |
Outage episodes by size in 2023: 18 reached 100+ customers, 2 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 Day County reported on EIA Form 861 for 2023, 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 | 2023 | 2.4 hrs | 1.78 | 1.9 hrs | 1.68 |
| NorthWestern Energy - (SD) | 2023 | 1.9 hrs | 1.37 | 74 min | 1.03 |
| Northern Electric Coop, Inc | 2023 | 74 min | 0.67 | 54 min | 0.55 |
| WAPA-- Western Area Power Administration | - | - | - | - | - |
| Montana-Dakota Utilities Co | - | - | - | - | - |
| Codington-Clark Elec Coop, Inc | - | - | - | - | - |
| Lake Region Electric Assn, Inc - (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 n/a of South Dakota's customers in 2023; utilities it does not see are not counted.
- Hours per customer = outage customer-minutes ÷ 4,051 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. Day County has data for 2019–2025.
Cite this report
MassOutage (massoutage.com), Day County, SD annual power outage report, 2023, 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/2023/south-dakota/day-county