Lands belonging to the state, and school, county, school district and other lands belonging to public corporations and which are not devoted to public use, which are benefited by any improvement instituted under the provisions of this chapter, shall be assessed in the same manner as lands of private persons and corporations, and the assessment shall be paid by the proper authorities.
RCW 91.08.575
Assessment procedure: RCW 91.08.270 through 91.08.380, 91.08.520.