Seattle City Light has approximately 85,000 streetlights in its 131-square-mile service territory that provide lighting on residential and arterial streets. There are about 20,000 metal streetlight poles, and about 17,000 pieces of related metal equipment, such as handhole covers located on the ground near the poles.
Contact voltage can occur on the surface of metal street light structures, street signs, or other fixtures that can become energized. It may pose a risk for shock. If street equipment becomes energized, pedestrians and their pets may encounter situations of contact voltage when contact is made.
City Light tests all its streetlights for contact voltage annually.
Seattle City Light completed its annual testing of metal streetlights and related structures in October 2012. The full report can be found here.
A total of seven fixtures were found with more than 30 volts. Five of those pieces of equipment were Seattle City Light fixtures and two belong to private entities. In 2011, two fixtures were found with voltage amounts greater than 30. Any City Light fixture with more than 3 volts of energy was repaired immediately or de-energized until the necessary repairs could be made.
In all, 52 fixtures were found to have some amount of voltage. Of that number, 18 were not City Light fixtures. There was a decrease in the total number of voltage incidents in2012, down from 61 in; and 158 events in 2010.
A number of factors contribute to contact voltage, which include aging infrastructure, weather, improper installation, rodent activity, copper wire theft, and corrosion. To address these factors, a 10-year horizon plan has been drafted that prioritizes infrastructure replacement and refurbishment. The plan indicates where City Light needs to strategically invest available budget to bring the streetlight assets up to current safety codes.
The best way to avoid contact voltage is to exercise caution while walking. Most cases of contact voltage occur during winter months when weather can be a factor and when streetlights are on for longer hours.
Here are some tips on how to avoid possible contact voltage:
When walking your pet, be aware if your pet acts strangely around any potentially energized metal equipment;
Avoid contact with metal equipment that could be energized;
Don't tie your pet's leash to a streetlight or near a handhole;
Report any streetlights that remain on during the day, or that flicker during the evening. This could indicate a problem;
Always immediately report any situation you are concerned about to us by calling (206) 684-7056. After normal business hours, call (206) 684-7400.
Streetlights are an important part of a safe community. City Light is committed to maintaining the streetlight system and to do so safely. If you have any questions or concerns about a streetlight, please contact us immediately at (206) 684-7056.