Power outage history
Minnehaha County South Dakota
5.6hours
without power for the average customer in a typical year, 2018–2025
15th most of 32 in South Dakota 15% 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 Minnehaha's customers who were without power at that day's worst moment.
Year by year
Hours in the dark, per customer
2019 was the worst well-recorded year, at 10 hours for the average customer. Hatched years have a thin record and are left out of the averages.
Minnehaha, 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 | 16,409 | 18% | 2.1 d | 46 h | 327k |
| Apr 10, 2019 | Flooding | 10,809 | 12% | 3.3 d | 2.6 d | 258k |
| Sep 10, 2019 | Thunderstorms | 13,763 | 15% | 41 h | 37 h | 195k |
| Jul 5, 2022 | Thunderstorms | 23,986 | 26% | 26 h | 21 h | 165k |
| May 30, 2022 | Thunderstorms | 9,920 | 11% | 38 h | 34 h | 146k |
| Jan 14, 2022 | Winter storm | 1,367 | 1% | 2.8 d | – | 91k |
| Jan 3, 2020 | No storm report | 2,164 | 2% | 3.0 d | – | 79k |
| Jun 17, 2024 | No storm report | 11,079 | 12% | 4.0 h | 3.5 h | 39k |
| Jul 28, 2025 | Thunderstorms | 3,228 | 4% | 17 h | – | 35k |
| Jul 28, 2025 | Heat | 3,821 | 4% | 13 h | – | 21k |
| Jul 20, 2019 | Thunderstorms | 6,194 | 7% | 5.8 h | 5.8 h | 21k |
| Jun 22, 2015 | Thunderstorms | 6,655 | 7% | 4.5 h | 14 h | 20k |
| Nov 8, 2025 | Winter storm | 6,588 | 7% | 3.5 h | 2.2 h | 19k |
| May 7, 2018 | Flooding | 13,253 | 14% | 1.5 h | 30 min | 16k |
| Feb 16, 2021 | Winter storm | 7,033 | 8% | 2.8 h | 2.0 h | 16k |
| Apr 28, 2016 | No storm report | 7,515 | 8% | 2.8 h | 2.0 h | 13k |
| Aug 5, 2023 | No storm report | 7,150 | 8% | 4.5 h | 3.5 h | 13k |
| Jun 20, 2022 | Thunderstorms | 2,982 | 3% | 4.8 h | – | 13k |
| Aug 27, 2015 | Flooding | 5,004 | 5% | 2.8 h | 1.5 h | 12k |
| May 1, 2017 | No storm report | 1,966 | 2% | 7.5 h | – | 11k |
| Jun 17, 2016 | Thunderstorms | 4,461 | 5% | 3.5 h | – | 11k |
| Dec 28, 2018 | No storm report | 4,384 | 5% | 2.5 h | – | 11k |
| Oct 18, 2019 | No storm report | 4,405 | 5% | 2.2 h | – | 9.9k |
| Aug 4, 2024 | No storm report | 2,700 | 3% | 3.8 h | – | 9.9k |
| Aug 6, 2025 | Thunderstorms | 4,127 | 4% | 3.2 h | – | 9.3k |
| Aug 6, 2021 | Thunderstorms | 7,171 | 8% | 1.2 h | 1.2 h | 8.9k |
| Nov 24, 2022 | No storm report | 5,171 | 6% | 1.8 h | 2.2 h | 8.9k |
| Jul 25, 2023 | Heat | 5,740 | 6% | 2.0 h | 1.8 h | 8.3k |
| Jul 31, 2023 | No storm report | 2,870 | 3% | 2.8 h | – | 7.9k |
| Nov 22, 2015 | No storm report | 1,785 | 2% | 4.0 h | – | 7.1k |
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 Minnehaha from twelve hours before it began to its peak. Matching shows coincidence, not proof of cause.
- Thunderstorms 50%
- No storm on record 22%
- Flooding 17%
- Winter storm 7.8%
- Heat 2.4%
- Windstorm 0.8%
Who keeps the lights on
Utilities serving Minnehaha
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 |
| City of Sioux Falls | SD | – | – | – | 12.8 | 9.8k |
| 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 91,940 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 →