Wash. Rev. Code § 36.88.310
All land, premises or property necessary for right-of-way or other purposes in the construction or improvement of any county road, including bridges, sidewalks, curbs and gutters and the drainage facilities therefor, under this chapter may be acquired by the county acting through its board of county commissioners, either by gift, purchase or by condemnation. In the event of any exercise of the power of eminent domain, the procedure shall be the same as is provided by law for the securing of right-of-way for county roads. The title to all property acquired for any construction or improvement under this chapter shall be taken in the name of the county. The county commissioners in any eminent domain action brought to secure any property for construction or improvement under this chapter may pay any final judgment entered in such action with county road funds and take possession of the particular property condemned. In the event of any such payment the county commissioners may require that the county road fund be reimbursed out of the particular county road improvement fund of the district for which the property was acquired.
RCW 36.88.310