Power outage history
Fall River County South Dakota
6.1hours
without power for the average customer in a typical year, 2018–2025
14th most of 32 in South Dakota close to 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 Fall River's customers who were without power at that day's worst moment.
Year by year
Hours in the dark, per customer
2025 was the worst well-recorded year, at 15 hours for the average customer. Hatched years have a thin record and are left out of the averages.
Fall River, 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 |
|---|---|---|---|---|---|---|
| Dec 18, 2025 | Windstorm | 2,302 | 57% | 4.8 d | 13 h | 34k |
| Mar 14, 2021 | Winter storm | 1,001 | 25% | 28 h | 10 h | 18k |
| Nov 13, 2025 | No storm report | 4,055 | 100% | 5.2 h | 3.2 h | 14k |
| Jun 9, 2023 | No storm report | 133 | 3% | 4.1 d | – | 13k |
| Oct 12, 2020 | No storm report | 1,459 | 36% | 6.2 h | 12 h | 9.1k |
| Sep 23, 2023 | No storm report | 2,235 | 55% | 6.0 h | 2.0 h | 8.2k |
| Apr 6, 2021 | Winter storm | 918 | 23% | 23 h | 8.2 h | 7.1k |
| Sep 1, 2020 | No storm report | 173 | 4% | 43 h | – | 3.8k |
| Aug 21, 2025 | No storm report | 1,639 | 40% | 2.2 h | 2.2 h | 3.7k |
| Oct 2, 2024 | No storm report | 548 | 14% | 5.5 h | 5.5 h | 2.6k |
| Aug 18, 2024 | No storm report | 1,667 | 41% | 1.5 h | 11 h | 2.5k |
| Feb 11, 2016 | No storm report | 3,277 | 81% | 48 min | 48 min | 2.5k |
| May 21, 2021 | No storm report | 405 | 10% | 7.0 h | 6.8 h | 2.4k |
| Dec 22, 2022 | Winter storm | 506 | 12% | 4.5 h | 9.8 h | 2.3k |
| Jan 13, 2024 | Winter storm | 518 | 13% | 5.0 h | 4.0 h | 1.7k |
| Oct 18, 2020 | No storm report | 456 | 11% | 6.2 h | 5.8 h | 1.5k |
| Mar 12, 2024 | No storm report | 521 | 13% | 2.5 h | 12 h | 1.3k |
| Jun 12, 2017 | Thunderstorms | 90 | 2% | 13 h | – | 1.2k |
| Mar 29, 2022 | No storm report | 162 | 4% | 7.2 h | – | 1.2k |
| Jul 15, 2019 | No storm report | 965 | 24% | 2.8 h | 2.8 h | 1.2k |
| Jul 2, 2022 | Thunderstorms | 79 | 2% | 16 h | – | 1.2k |
| Sep 4, 2024 | No storm report | 164 | 4% | 5.2 h | – | 855 |
| Jul 23, 2023 | No storm report | 173 | 4% | 5.0 h | – | 773 |
| May 23, 2021 | Thunderstorms | 433 | 11% | 2.8 h | 2.5 h | 772 |
| Apr 15, 2019 | No storm report | 588 | 14% | 1.2 h | 1.2 h | 735 |
| May 17, 2024 | Thunderstorms | 380 | 9% | 4.8 h | 3.8 h | 705 |
| Jun 28, 2023 | No storm report | 1,366 | 34% | 30 min | 30 min | 683 |
| Aug 17, 2021 | No storm report | 146 | 4% | 4.2 h | – | 620 |
| Nov 26, 2022 | No storm report | 302 | 7% | 2.5 h | 1.8 h | 618 |
| Apr 18, 2023 | Thunderstorms | 188 | 5% | 3.2 h | – | 611 |
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 Fall River from twelve hours before it began to its peak. Matching shows coincidence, not proof of cause.
- No storm on record 54%
- Windstorm 23%
- Winter storm 20%
- Thunderstorms 3.5%
Who keeps the lights on
Utilities serving Fall River
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 |
|---|---|---|---|---|---|---|
| Black Hills Power, Inc. | Investor Owned | 541 | 43 | 2.27 | 15.1 | 68k |
| Black Hills Electric Coop, Inc | Cooperative | 2,487 | 120 | 3.41 | 14.8 | 9.4k |
| Niobrara Electric Assn, Inc | WY | – | – | – | – | 86 |
| 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.
Next door
Neighbouring counties
- Sioux, NE 12 h
- Custer 11 h
- Fall River (this county) 6.1 h
- Niobrara, WY 3.8 h
- Dawes, NE 1.5 h
- Oglala Lakota 1.0 h
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 4,055 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 →