Columbia-area utility customers experienced a series of brief power interruptions over the weekend as extreme temperatures strained transmission equipment and pushed electrical demand to summer records, utility officials said.
High temperatures, sagging lines and system "blinks"
As the Columbia area reached 100 degrees Monday with feels-like temperatures even higher, Tri-County Electric Cooperative and Santee Cooper reported brief outages known as "blinks" tied to heat-related line sag. The National Weather Service had issued a heat advisory for the region Sunday.
Santee Cooper officials said Monday’s heat produced a record summer peak on the utility’s system. In the Tri-County cooperative's Midlands service area, which covers six counties, the system recorded five power blinks Monday and one on Saturday. The cooperative specifically reported outages Monday in the Lower Richland area.
"An inspection Monday found that the line was sagging, something that can happen during periods of extreme heat as the metal in transmission lines expands," said Mollie Gore, a Santee Cooper spokesperson.
In this incident the sagging transmission line came into contact with a Dominion Energy distribution line running underneath it. When transmission lines contact another object such as tree branches or another line, service can be interrupted. Dominion Energy later lowered its line in the affected area, and Santee Cooper said the issue is expected to be resolved.
Local impacts and broader context
Officials characterized the events as brief interruptions rather than extended outages, but the occurrences illustrate how heat extremes can affect electric infrastructure and system reliability. Santee Cooper and other utilities have noted higher summer peaks and added stress on grids as heat waves grow more frequent.
- Location affected: Lower Richland area within Tri-County Electric Cooperative’s Midlands service territory.
- Duration: Multiple brief "blinks" — five on Monday, one on Saturday.
- Cause: Transmission-line sag from extreme heat leading to contact with a distribution line; Dominion Energy lowered its line to address the problem.
Climate and energy researchers have linked rising temperatures to increased stress on power systems nationwide. While utility spokespeople tied Monday’s blinks to thermal expansion of conductors, the broader trend of higher demand during heat waves also contributes to system strain. Santee Cooper’s statement that the system reached a record summer peak Monday highlights that rising demand accompanied the equipment impact.
What officials recommend
Though specific emergency instructions tied to these blinks were not issued, residents are reminded of general heat- and power-safety guidance from local and federal agencies during heat advisories: stay hydrated, seek cool environments, and report outages to your utility. Utilities typically ask customers to report any sustained loss of power or safety hazards such as downed lines.
| Metric | Reported value |
|---|---|
| Columbia temperature Monday | 100°F |
| Power blinks recorded (Tri-County) | 5 on Monday, 1 on Saturday |
| Area specifically reported | Lower Richland |
Utility officials said the crossing distribution line has been lowered and the immediate issue in that location is expected to be resolved. As extreme heat events continue to challenge infrastructure, local customers and emergency planners will be watching how utilities manage demand and equipment stress during peak periods.
WE NEWS will continue to monitor updates from Santee Cooper, Tri-County Electric Cooperative and Dominion Energy for any changes to restoration efforts or further advisories affecting Columbia-area residents.
