On a foggy day in the Puget Sound region, you'll often hear the regionally distinctive sound of a ferry horn.

But on this foggy day in West Seattle, drivers and passengers instead heard the voice of a dock worker named Tiffany.

"Sorry, no boats today," she could be heard saying over and over to drivers near Fauntleroy. "We'll see you tomorrow."

That's because of what the Washington State Ferry System described as a massive sickout. WSF said 23 engine room employees called in sick Monday morning. The agency said it sought qualified relief workers to cover the open positions, but each employee qualified to fill them declined. At one point, the agency said 13 of its 18 operating vessels were out of service.

RELATED | Crew call-outs cause major disruptions to Washington ferry service, 72% not in operation

By Monday afternoon, some service had returned, but WSF's travel bulletin still listed Seattle-Bainbridge, Edmonds-Kingston and Fauntleroy-Vashon-Southworth as out of service because of crew shortages. Mukilteo-Clinton and Seattle-Bremerton were operating with one boat, and WSF warned of an estimated two-hour wait for drivers departing Mukilteo.

In the San Juan Islands, WSF said the Chelan and Yakima were expected to resume limited evening service. The Samish's remaining sailings after the 5:35 p.m. departure from Anacortes were canceled. WSF said dispatch was continuing to try to fill open positions and that it would provide updates as conditions changed.

MEBA Secretary-Treasurer Roland “Rex” Rexha, who met with Gov. Bob Ferguson on Monday, told KOMO News the union did not organize a job action.

“The union didn't take any action today,” Rexha said. “This is not a coordinated effort by any means.”

Rexha said the ferry system has become too dependent on overtime to cover a shortage of marine engineers, a problem he said began before Ferguson took office. He said one member had worked more than 1,800 overtime hours in the past year, while union members collectively logged more than 100,000 overtime hours to cover crewing shortfalls.

“One person taking off sick shouldn't shut down the service that people rely on, and neither should 23,” Rexha said.

Ferguson said he met with local and national MEBA leadership Monday morning and heard concerns about staffing. The governor said he remained committed to improving staffing levels but criticized the effect of the cancellations on riders.

“Causing significant harm and inconvenience to the people of Washington state is not the way to address those issues,” Ferguson said. “I was very direct in our meeting: My expectation is that every vessel on every route is fully operational no later than the first vessel sailing tomorrow morning.”

Rexha said he agreed with the goal but stopped short of guaranteeing the system would be fully restored.

“We want the vessels to run,” he said. “We want them to run on time. We want them to run safely. I think we all have the same goals here.”

Asked whether he expected every route to be operating Tuesday morning, Rexha said: “I hope so, and I plan on it. We plan on everything running the way they're supposed to.”

The dispute also exposed a sharp divide over pay and working conditions. In its social media posts Monday, WSF highlighted the compensation of staff chief engineers, saying they have a $157,000 base salary and can earn more than $350,000 annually with overtime, along with sick leave, vacation and retirement benefits.

Rexha called the messaging “passive aggressive” and said it left out the qualifications required of the engineers. He said chief engineers can spend 15 years working toward the position and hold U.S. Coast Guard licenses. He also argued that ferry management has not properly completed a prevailing wage survey required by state law and that comparable mariners earn more elsewhere in the industry.

“We want to be partners on this. We want to find a solution,” Rexha said. “In the end, our goal is to make sure the ferries run on time and safely.”

WSF said the ferries cannot operate without the required engine room positions being filled. Riders can check the agency's online travel alerts and real-time map before heading to a terminal.