A complicated confluence of considerations means a cut in service for the Coupeville-to-Port Townsend ferry run later this month.

Washington State Ferries announced that, beginning June 24, the route will be reduced to one boat for at least a week.

Ian Sterling, State Ferries spokesman, said one of the main factors leading to the temporary reduction is that the vessel Hyak will be decommissioned at the end of the month because lawmakers decided not to continue funding the boat, which has served as a backup throughout the system.

The decision to put the Hyak out to pasture wasn’t a big surprise. As Sterling explained, the vessel is “really old and hasn’t been maintained.” The only reason it’s still in use is thanks to “the Herculean efforts” of the engine crew, he said.

“It will be sold as a non-working vessel,” he said. “We’ve run this thing into the ground.”

The vintage vessel went into service in 1967. As a testament that it’s from a different era, the chairs in the boat were designed to be movable, Sterling said, in order to make space for square dancing.

At the same time, several other vessels in the hard-working fleet require planned maintenance or unexpected fixes. Several engine overhauls on aging vessels had been previously deferred and further delay would mean “an unacceptably high risk for unplanned service disruptions during the summer season,” according to a ferry official.

The 60-year-old Tillikum, for example, needs both main engines overhauled; they are currently 16,000 hours behind the target overhaul interval of 40,000 hours. This boat is so old, Sterling said, that its drive motor is from a surplus World War II destroyer.

In the ensuing shuffle of boats, State Ferries officials looked at ridership numbers and decided that reducing service on the Coupeville-Port Townsend route would affect the least number of people and would have the smallest impact on revenues.

One of the boats from Coupeville will float over to the San Juan Islands for the week of June 24; it will be on the inter-island route, Sterling said.

The hope is that the single-boat service to Coupeville will only be for a week, Sterling said, but it may end up being longer. People planning on taking the ferry might want to consider driving around.

“It’s not a fun way to start out the summer season,” he said.