Washington State Ferries will cut service by about half on Bremerton and Bainbridge Island runs beginning Sunday as ridership drops steadily during the COVID-19 outbreak.

The state's Triangle route, serving Southworth-Vashon Island-Fauntleroy, will shift to a two-boat schedule as Bremerton and Bainbridge runs will shift to one-boat service. Also beginning on Sunday, the final roundtrip of each sailing day will be suspended on the Bainbridge, Bremerton and Mukilteo-Clinton runs. On the Kingston-Edmonds route, the final roundtrip will be suspended on Fridays and Saturdays only. A handful of daily sailings on the Triangle route will also be suspended.

The moves will begin on Sunday and remain in place through at least April 25, the agency said.

Check wsdot.com/ferries for the most up-to-date schedules.

More:As COVID-19 response grows, people stay home and ferries run light

As of Thursday, state ferry ridership was down about 60% compared with the last week of February, the agency said. Walk-on passenger numbers have plummeted by more than 80%, and vehicles have dropped by nearly half.

"This is something we've never done before," WSF spokesman Ian Sterling said, noting that ridership has dropped back to 1960s-era levels.

"This may not be the end of service reductions, but for now this is what we're able to do," he said.

The agency moved to drop back service because of decreased ridership and as the number of crew members available fell because of illness or necessary isolation, Sterling said. Fewer sailings allow crews to be combined and also allow more time for them to deep clean and sanitize vessels, he said.

A new overhead announcement now being played on vessels advises passengers to stay in their vehicles if possible.

"If you don't have to be, don't be on a ferry boat," Sterling said. "Reserve the ferry boats for emergency personnel, goods and services, that sort of thing."

Nathan Pilling is a reporter covering Bainbridge Island, North Kitsap and Washington State Ferries for the Kitsap Sun. He can be reached at 360-792-5242, nathan.pilling@kitsapsun.com or on Twitter at @KSNatePilling.

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