Power outage causes and restoration

Why power goes out

Planned outages: We sometimes interrupt service for maintenance work. We work to inform you and your community in advance of such outages.
Unexpected outages: Equipment, weather and tree problems cause most outages.
Here’s a breakdown:

unexpected outages pie chart
  • Animal contact 11%
  • Human accidents, vandalism, etc. 7%
  • Miscellaneous such as mechanical damage, construction error, fire, etc. 7%
  • Fallen trees and tree growth 20%
  • Weather such as lightning, wind, rain, snow, heat, cold and ice 27%
  • Equipment wear and tear 29%

Momentary outages: Power outages of less than 5 minutes are considered momentary. Momentary outages are caused by wildlife, weather or trees making brief contact with our electric lines, or by contractor dig-ins into underground facilities. In many instances, our electrical system can reset itself within minutes. Other times, a repair crew is sent to fix the problem.

Power restoration sequence

power restoration sequence
  1. Repair live wires and address potentially life-threatening situations.
  2. Communicate with American Transmission Company to address any issues with their transmission lines.
  3. Fix substation equipment.
  4. Restore main distribution lines.
  5. Repair secondary lines serving neighborhoods.
  6. Fix service lines to individual homes and businesses.