When delivered it acted as a relief boat until it was moved to the Mukilteo–Clinton route in the mid 1980s.

In 1990, in order to keep up with growing demand, the Kittitas underwent a capacity expansion by adding additional vehicle areas above the vehicle areas along the outside edge of the ferry.

These upgrades had been planned for in the original design of the vessels.

The ferry's passenger cabin was updated in the late 1990s.

Included in the upgrades were the removal of many tables located in the passenger cabin to allow for the bench seats to be spaced closer together in some sections of the ship.