Seattle City Light warns that coming rain could mean outages

Utility prepares for possible outages due to effects of recent dry weather

Seattle City Light has crews ready for possible outages with forecasts calling for an end to the 80-day dry spell that has been in place in the Puget Sound area. No significant rain has fallen since July 20 and that can have an impact on both the overhead and underground electrical systems.

"What we are seeing is the possibility of outages due to a couple of issues,” says City Light Systems Control Director Pawel Krupa. “For overhead power lines, summer can bring a buildup of dust. When it rains after a long dry spell, that dust gets wet and can cause electricity leakage or short circuits. You might hear a buzzing sound when this starts to happen. That sound is the coating of the insulators burning off. When the coating is gone, a short circuit happens, creating an outage. A heavier rain will wash away the dirt and dust better.

“The same is true in our underground system. Underground power lines are insulated and designed to float in water that fills the concrete vaults, but over time the insulation becomes brittle.  As temperatures begin to drop and with shorter daylight hours, demand for power increases. The increased flow of electricity puts more stress on the cable, increasing the risk of failure. If the insulation on an underground cable cracks, any water in the vault will cause a short,” adds Krupa.

Another problem with the coming rains – leaves are still on the trees.  Many of the leaves and branches are very dry and the ground has been very dry.  A significant amount of wind and rain will bring leaves and branches down – and possibly could affect the shallow-root evergreen trees that are prevalent in the northwest. This could mean trees and branches falling into the power lines.

“Even though City Light will do more than 625 miles of power line trimming this year, we can’t protect against every falling tree,” says Brent Schmidt, manager of the utility’s Vegetation Management program.  “We would like to know when there are conflicts between trees and wires, especially if there is any arcing or sparking.” Customers are asked to call the utility at 386-1733 or look at our website  if they need more information.

The utility encourages everyone to be ready if there is an outage. One important step residents can take is to put together an emergency preparedness kit. A kit should include enough food and supplies to last your family for at least three days, hand-crank or battery-operated flashlight and radio, fresh batteries, a survival blanket, a first aid kit, pocket tissues and hand sanitizer wipes. For a checklist and other tips, go to www.takewinterbystorm.org.

City Light also reminds customers to be safe. Downed lines can be dangerous.

Here’s what customers can do if they experience a power outage:

• Do not go near any downed wire. Wires should always be assumed to be "live" and dangerous. If someone seeks a downed wire, they should call (206) 684-3000;
• Do not use a barbecue grill or generator inside the house or in a garage that is attached to the house.
• Do not use a grill or generator near a home air intake vent or near windows;
• Do not use fossil fuel burning auxiliary heating sources;
• Know how to manually override electric garage doors, security doors and gates;
• Have a land line phone or fully charged cell phone available -- cordless phones won’t work when the power is out;
• Make sure City Light has your home phone number and your cell phone number to ensure the system recognizes your telephone number if you call in to report an outage.  Update your account information;
• Unplug electrical appliances if the power goes out so that when the power comes back on, there won’t be a surge that could damage sensitive electronic equipment;
• Use battery-powered flashlights - not candles or oil lamps;
• Close doors, windows, curtains, and unused fireplace dampers to retain heat if there is an outage.

A reminder that you can now track power outages on your mobile phone if you have Internet access. Just type into your browser for the latest information while you’re on the go.

Seattle City Light is the 10th largest public electric utility in the United States.  It has some of the lowest cost customer rates of any urban utility, providing reliable, renewable and environmentally responsible power to nearly 1 million Seattle area residents.  City Light has been greenhouse gas neutral since 2005, the first electric utility in the nation to achieve that distinction.