More than 1,500 Holy Cross Energy customers in the Aspen area were without power for nearly three hours Wednesday afternoon, according to an outage map on the Holy Cross website.

The outage was related to an explosion at an underground utility vault near Park Circle at the base of Smuggler Mountain that also occurred Wednesday afternoon, Holy Cross Energy spokeswoman Jenna Weatherred confirmed.

Wednesday’s outage impacted more people and lasted longer than it might have otherwise because Holy Cross was already rerouting power transmission away from a switchgear box located near the Castle Creek bridge where an arc flash caused a small fire Sunday afternoon, she said.

After an investigation, Holy Cross crews determined that Sunday’s incident was most likely caused by equipment failure, according to Weatherred.

As for Wednesday’s explosion, “it could be lots of things but my guess … with an underground vault, it would be equipment failure,” she said.

Utility companies were on the the scene by early Wednesday evening. Crews began power restoration by 6:10 p.m., according to an email sent to some Holy Cross customers.

By 8:15 p.m. service was restored in most of Aspen but approximately 50 customers were still without power, Weatherred said; she expected power for those customers to be restored within an hour.

Fire crews responded to the site and were “securing the scene, investigating what occurred and making sure there are no further hazards” after the explosion, said Jake Andersen, deputy chief of operations for Aspen Fire Protection District.

Three fire engines initially responded to the explosion, but one was rerouted to town to respond to several other incidents, including a small dumpster fire behind the Wheeler Opera House and people stuck in an elevator, according to Andersen. The outage also tripped several fire alarms in town, he said.

“Everything fell apart for an hour, and then we put it all back together,” he said.

Crews from the Aspen Ambulance District also responded to the explosion, in part to wait in the wings and ensure safety of fire crews who were on the scene, Andersen said. All told, the evening required extensive volunteer response.

At least 1,300 customers were without power in the North 40 area near the Aspen airport and another 200 near downtown, according to Holy Cross. The website originally reported more than 1,600 customers without power in the North 40 but later updated the map.

The outage occurred around 4:45 p.m.

The outage did not impact the airport, according to Caroline Bonynge, director of operations, safety and security for the Aspen-Pitkin County Airport.

Members of the Aspen-Pitkin County Housing Authority had to pause a meeting Wednesday because some of the board members were affected by the outage.

The city of Aspen has its own power grid, so the area around downtown was not affected.