Wash. Rev. Code § 36.87.140
Whenever a county road or any portion thereof is vacated the legislative body may include in the resolution authorizing the vacation a provision that the county retain an easement in respect to the vacated land for the construction, repair, and maintenance of public utilities and services which at the time the resolution is adopted are authorized or are physically located on a portion of the land being vacated: PROVIDED, That the legislative body shall not convey such easement to any public utility or other entity or person but may convey a permit or franchise to a public utility to effectuate the intent of this section. The term "public utility" as used in this section shall include utilities owned, operated, or maintained by every gas company, electrical company, telephone company, telegraph company, and water company whether or not such company is privately owned or owned by a governmental entity.
RCW 36.87.140