Power outage history
Lake County South Dakota
5.0hours
without power for the average customer in a typical year, 2018–2025
19th most of 32 in South Dakota 23% below the national median
Every day since 2015
Eleven years, one night at a time
Each cell is a day. The brighter it is, the larger the share of Lake's customers who were without power at that day's worst moment.
Year by year
Hours in the dark, per customer
2022 was the worst well-recorded year, at 20 hours for the average customer. Hatched years have a thin record and are left out of the averages.
Lake, hours without power per customer
The record
The biggest outages since 2015
Ranked by customer-hours lost: customers out multiplied by how long they stayed out. Times are local.
| Began | Storm | Peak out | Share | Lasted | 90% restored | Customer-hours |
|---|---|---|---|---|---|---|
| May 12, 2022 | Thunderstorms | 3,402 | 42% | 4.1 d | 2.6 d | 142k |
| Oct 2, 2017 | No storm report | 4,106 | 51% | 5.5 h | 3.5 h | 20k |
| Nov 8, 2017 | No storm report | 2,421 | 30% | 5.8 h | 4.0 h | 11k |
| Apr 11, 2019 | Winter storm | 179 | 2% | 2.7 d | – | 9.9k |
| Jul 21, 2021 | No storm report | 609 | 8% | 16 h | 16 h | 9.7k |
| Dec 26, 2024 | No storm report | 151 | 2% | 27 h | – | 3.1k |
| Oct 3, 2017 | No storm report | 783 | 10% | 3.5 h | 1.2 h | 2.7k |
| Jul 4, 2017 | No storm report | 534 | 7% | 4.2 h | 1.5 h | 2.2k |
| Jun 29, 2022 | No storm report | 599 | 7% | 3.8 h | 30 min | 1.3k |
| Sep 12, 2019 | Flooding | 189 | 2% | 6.8 h | – | 1.2k |
| Feb 23, 2022 | Winter storm | 187 | 2% | 6.0 h | – | 1.1k |
| Apr 10, 2019 | No storm report | 178 | 2% | 9.0 h | – | 1.1k |
| Jun 11, 2025 | No storm report | 190 | 2% | 5.8 h | – | 1.0k |
| Jul 20, 2019 | Thunderstorms | 440 | 5% | 6.5 h | 2.0 h | 1.0k |
| Jun 1, 2021 | No storm report | 627 | 8% | 1.5 h | 1.2 h | 940 |
| Apr 23, 2022 | Windstorm | 161 | 2% | 5.5 h | – | 808 |
| Jun 28, 2021 | No storm report | 632 | 8% | 1.2 h | 9.8 h | 790 |
| Jan 23, 2023 | No storm report | 244 | 3% | 3.2 h | – | 780 |
| May 29, 2023 | No storm report | 631 | 8% | 1.5 h | 1.0 h | 776 |
| Jul 11, 2017 | No storm report | 512 | 6% | 1.5 h | 1.5 h | 768 |
| Sep 29, 2021 | No storm report | 188 | 2% | 4.2 h | – | 758 |
| Jul 23, 2016 | Heat | 291 | 4% | 3.5 h | – | 688 |
| May 27, 2020 | No storm report | 269 | 3% | 2.5 h | – | 672 |
| Aug 29, 2025 | No storm report | 190 | 2% | 3.5 h | – | 665 |
| Mar 9, 2019 | Winter storm | 185 | 2% | 3.5 h | – | 637 |
| Jul 5, 2022 | No storm report | 213 | 3% | 2.8 h | – | 534 |
| Jul 24, 2021 | No storm report | 213 | 3% | 2.5 h | – | 532 |
| Jun 6, 2020 | Thunderstorms | 222 | 3% | 2.8 h | – | 496 |
| Jul 4, 2023 | No storm report | 202 | 3% | 3.0 h | – | 490 |
| Apr 30, 2023 | Windstorm | 431 | 5% | 1.2 h | 30 min | 486 |
After the peak
How fast the lights come back
Each line is one major outage, from its peak. The amber line is the typical path.
When it happens
The outage clock
Customer-hours out by month (rings, January innermost) and local hour, 2018–2025.
What was happening
Weather behind the outages
Each outage is matched to NOAA storm reports for Lake from twelve hours before it began to its peak. Matching shows coincidence, not proof of cause.
- Thunderstorms 75%
- No storm on record 18%
- Winter storm 6.1%
- Flooding 0.8%
- Windstorm 0.8%
Who keeps the lights on
Utilities serving Lake
As each utility reports to the Energy Information Administration for its whole South Dakota territory, not this county alone. Outage minutes include major storm days.
| Utility | Type | Outage min / yr | Excl. major storms | Outages / yr | Residential ¢/kWh | Customers |
|---|---|---|---|---|---|---|
| Northern States Power Co - Minnesota | Investor Owned | 160 | 58 | 0.88 | 13.1 | 94k |
| Sioux Valley SW Elec Coop | Cooperative | 59 | 59 | 1.64 | 13.9 | 23k |
| Southeastern Electric Coop Inc | Cooperative | 24 | 24 | – | 13.0 | 21k |
| Otter Tail Power Co | Investor Owned | 191 | 189 | 1.73 | 11.4 | 9.1k |
| City of Madison | Municipal | – | – | – | 12.4 | 2.8k |
| WAPA-- Western Area Power Administration | Federal | – | – | – | – | – |
EIA Form 861, latest year each utility reported. Outage minutes are SAIDI, the yearly minutes the average customer goes without power; outages a year are SAIFI.
About these numbers
Notes
Outages come from the EAGLE-I record of utility outage maps collected every 15 minutes by Oak Ridge National Laboratory. Hours without power are customer-hours divided by the county's 8,064 electricity customers. Averages use well-covered years from 2018. Outages shorter than 15 minutes, and utilities that publish no outage map, are not in the record, so these figures understate the total. How every number is made →