County annual report · FIPS 46137
2018 Ziebach County, SD Power Outage Report
In 2018, customers in Ziebach County, SD went without power for an average of 0.2 hours, a total of 260 customer-hours (South Dakota average 1.1 hours). That ranks 20th worst of 30 South Dakota counties and 2630th of 2,798 nationally.
Compared with SD, the US
Coverage line is EAGLE-I's share of South Dakota customers tracked each year.
Biggest outages in Ziebach County, 2018
The 3 outage episodes with the most customers out at once. Times are UTC.
| # | Started (UTC) | Ended (UTC) | Duration | Peak out | Customer-hours |
|---|---|---|---|---|---|
| 1 | May 28, 2018 04:45 | May 28, 2018 13:30 | 8h 45m | 33 | 257 |
| 2 | March 20, 2018 05:30 | March 20, 2018 07:15 | 1h 45m | 1 | 2 |
| 3 | October 23, 2018 04:00 | October 23, 2018 05:45 | 1h 45m | 1 | 2 |
Outage episodes by size in 2018: 0 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 Ziebach County reported on EIA Form 861 for 2018, 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 |
|---|---|---|---|---|---|
| WAPA-- Western Area Power Administration | - | - | - | - | - |
| Grand Electric Coop, Inc | - | - | - | - | - |
| West River Electric Assn Inc | - | - | - | - | - |
| Moreau-Grand Electric Coop Inc | - | - | - | - | - |
About this data
- Outage figures come from DOE/ORNL EAGLE-I, which records customers out by county every 15 minutes. EAGLE-I tracked about 46% of South Dakota's customers in 2018; utilities it does not see are not counted.
- Hours per customer = outage customer-minutes ÷ 1,374 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. Ziebach County has data for 2018–2025.
Cite this report
MassOutage (massoutage.com), Ziebach County, SD annual power outage report, 2018, 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/). https://massoutage.com/reports/2018/south-dakota/ziebach-county