POULSBO — Power was out for nearly an hour and a half before Puget Sound Energy crews turned the lights back on at 10:47 a.m.

The cause of the outage was unknown when power was restored. PSE crews traveled circuit lines searching for the error. But no interruptions — such as a fallen branch on a power line — were found, according to Ray Lane with PSE.

Customers served by the substation at 519 NW Liberty Road were affected.

Poulsbo went dark from City Hall to area traffic lights, along the east side of Liberty Bay, around 9:20 a.m., leaving approximately 2,100 PSE customers without power. All customers have had power restored.

Traffic was slowed along the city’s main roadways, such as Highway 305, during the outage.