In late 2019, Seattle City Light completed its 10th consecutive year conducting contact voltage testing. With the help of Osmose Utilities Services and Utility Testing and Geographic Information Systems (UTGIS), City Light was able to identify and repair seven instances, six City Light-owned assets and one privately-owned system, where metal structures or equipment were improperly energized with at least 30 volts of electricity. These instances were responded to and repaired immediately after being discovered. Both contractors supported the testing by calculating survey routes to ensure area coverage and using their mobile detection program to detect and log the events.
This year’s findings were significantly fewer than those in 2018, when 17 instances were discovered by this survey testing. Testing in 2018 also identified 17 instances of contact voltage of less than 30 volts, which were also responded to and either repaired or de-energized. Over the ten years of survey testing, no accidents or injuries have resulted from this method of testing.
Contact voltage events can be the result of many factors, including weather, improper installation, aging infrastructure and corrosion. City Light’s contact voltage testing and response is a demonstration of the utility’s commitment to safety, both for the public and for its employees. Surveying for contact voltage events can also help increase power quality and decrease vault fires.
It is important to note that most cases of contact voltage occur in the winter months when weather can be a factor. You can keep yourself and your loved ones safe by taking these tips into account:
- When walking your pet, be aware if your pet acts strangely around any potentially energized metal equipment.
- Don’t tie your pet’s leash to a streetlight or near a handhole.
- Avoid contact with metal equipment that could be energized.
- Report any streetlights that remain on during the day or that are flickering during the evening. This could indicate a problem.
- To report a malfunctioning streetlight or a streetlight that is out, visit seattle.gov/light/streetlight.
The full report can be found here: 2019 Contact Voltage Survey Results (PDF).