County annual report · FIPS 46037
2020 Day County, SD Power Outage Report
In 2020, customers in Day County, SD went without power for an average of 2.3 hours, a total of 9,390 customer-hours (South Dakota average 4.6 hours). That ranks 40th worst of 62 South Dakota counties and 2121st of 3,019 nationally.
Compared with SD, the US and 2019
Coverage line is EAGLE-I's share of South Dakota customers tracked each year.
Biggest outages in Day County, 2020
The 10 outage episodes with the most customers out at once. Times are UTC.
| # | Started (UTC) | Ended (UTC) | Duration | Peak out | Customer-hours |
|---|---|---|---|---|---|
| 1 | September 16, 2020 11:00 | September 16, 2020 11:15 | 15m | 571 | 143 |
| 2 | November 4, 2020 01:00 | November 4, 2020 03:00 | 2h | 571 | 1,142 |
| 3 | June 5, 2020 00:45 | June 5, 2020 13:45 | 13h | 382 | 991 |
| 4 | August 30, 2020 20:30 | August 30, 2020 22:30 | 2h | 320 | 412 |
| 5 | February 14, 2020 20:30 | February 14, 2020 21:00 | 30m | 133 | 67 |
| 6 | September 21, 2020 14:15 | September 21, 2020 16:45 | 2h 30m | 126 | 145 |
| 7 | July 23, 2020 20:45 | July 24, 2020 01:00 | 4h 15m | 108 | 386 |
| 8 | January 22, 2020 13:00 | January 23, 2020 06:30 | 17h 30m | 73 | 225 |
| 9 | September 9, 2020 14:15 | September 9, 2020 19:30 | 5h 15m | 62 | 190 |
| 10 | October 5, 2020 18:45 | October 5, 2020 20:30 | 1h 45m | 62 | 103 |
Outage episodes by size in 2020: 7 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 Day County reported on EIA Form 861 for 2020, 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 | 2020 | 1.6 hrs | 1.40 | 1.6 hrs | 1.40 |
| NorthWestern Energy - (SD) | 2020 | 2.6 hrs | 1.54 | 1.9 hrs | 1.28 |
| Northern Electric Coop, Inc | 2020 | 1.7 hrs | 0.62 | 1.6 hrs | 0.56 |
| 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 79% of South Dakota's customers in 2020; 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, 2020, 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/2020/south-dakota/day-county