Wash. Rev. Code § 36.55.070
All rights, privileges, or franchises granted or attempted to be granted by the board of county commissioners of any county prior to April 1, 1937, when such board of county commissioners was in regular or special session and when the action of such board is shown by its records, to any person to erect, construct, maintain, or operate any railway or poles, pole lines, wires, or any other thing for the furnishing, transmission, delivery, enjoyment, or use of electric energy, electric power, electric light, and telephone connection therewith, or any other matter relating thereto; or to lay or maintain pipes for the distribution of water, or gas, or to or for any other such facilities in, upon, along, through or over any county roads, are confirmed and declared to be valid to the extent that such rights, privileges, or franchises specifically refer or apply to any county road or county roads, or to the extent that any such county road has prior to April 1, 1937, been actually occupied by the bona fide construction and operation of such utility, and such rights, privileges, and franchises hereby confirmed shall have the same force and effect as if the board of county commissioners prior to the time of granting said rights, privileges, and franchises, had been specifically authorized to grant them.
RCW 36.55.070