Riders of the Clinton-Mukilteo ferry route may have experienced a surprise this week when they were directed to board using only the No. 2 slip.

The ferry system sent out an alert Jan. 27 to inform riders that the No. 1 slip is out of service due to maintenance. As of Friday, it was still out of commission.

Brian Vail, a communications consultant for Washington State Ferries, said in an email that debris needs to be removed from the slip before it can be opened again. Ferry workers he spoke to reported that the debris is coming from a damaged wingwall, which is one of the structures used to help guide the vessels as they dock.

Vail said the damage was likely caused from aging of the rub timbers.

“The plan is to assess and then repair the issue and the slip should be good to go this weekend,” he said, adding that a barge will arrive Saturday to fix things.

The slip being out of service caused delays this past week, according to alerts from the ferry system about the route.