County annual report · FIPS 47187
2018 Williamson County, TN Power Outage Report
In 2018, customers in Williamson County, TN went without power for an average of 0.8 hours, a total of 101K customer-hours (Tennessee average 2.1 hours). That ranks 36th worst of 71 Tennessee counties and 2379th of 2,798 nationally.
Compared with TN, the US and 2017
Coverage line is EAGLE-I's share of Tennessee customers tracked each year.
Biggest outages in Williamson County, 2018
The 10 outage episodes with the most customers out at once. Times are UTC.
| # | Started (UTC) | Ended (UTC) | Duration | Peak out | Customer-hours |
|---|---|---|---|---|---|
| 1 | June 14, 2018 08:00 | June 14, 2018 22:15 | 14h 15m | 6,761 | 3,412 |
| 2 | April 4, 2018 01:45 | April 5, 2018 02:00 | 1d | 4,600 | 4,048 |
| 3 | September 8, 2018 11:30 | September 8, 2018 12:15 | 45m | 3,474 | 1,298 |
| 4 | May 29, 2018 23:00 | May 30, 2018 00:45 | 1h 45m | 3,467 | 2,601 |
| 5 | September 23, 2018 00:30 | September 23, 2018 07:00 | 6h 30m | 3,466 | 1,757 |
| 6 | May 26, 2018 08:00 | May 26, 2018 23:45 | 15h 45m | 3,383 | 7,671 |
| 7 | June 15, 2018 22:45 | June 16, 2018 03:00 | 4h 15m | 3,031 | 3,089 |
| 8 | February 7, 2018 07:15 | February 7, 2018 18:00 | 10h 45m | 3,022 | 2,055 |
| 9 | October 8, 2018 13:15 | October 8, 2018 20:30 | 7h 15m | 2,948 | 2,248 |
| 10 | November 24, 2018 12:30 | November 24, 2018 14:15 | 1h 45m | 2,847 | 957 |
Outage episodes by size in 2018: 81 reached 100+ customers, 32 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 Williamson 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 |
|---|---|---|---|---|---|
| Duck River Elec Member Corp | 2018 | 2.9 hrs | 1.62 | 1.5 hrs | 1.29 |
| City of Dickson | 2018 | 2.5 hrs | 1.59 | 2.5 hrs | 1.59 |
| Nashville Electric Service | 2018 | 1.8 hrs | 1.56 | 1.8 hrs | 1.56 |
| Columbia Power System - (TN) | 2018 | 1.9 hrs | 1.81 | 61 min | 1.17 |
| Middle Tennessee E M C | - | - | - | - | - |
About this data
- Outage figures come from DOE/ORNL EAGLE-I, which records customers out by county every 15 minutes. EAGLE-I tracked about 55% of Tennessee's customers in 2018; utilities it does not see are not counted.
- Hours per customer = outage customer-minutes ÷ 123,583 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. Williamson County has data for 2015–2025.
Cite this report
MassOutage (massoutage.com), Williamson County, TN 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/); EIA Form 861 (utility reliability) (https://www.eia.gov/electricity/data/eia861/). https://massoutage.com/reports/2018/tennessee/williamson-county