Wash. Rev. Code § 58.17.155
Whenever a city, town, or county receives an application for the approval of a short plat of a short subdivision that is located adjacent to the right-of-way of a state highway, the responsible administrator shall give written notice of the application, including a legal description of the short subdivision and a location map, to the department of transportation. The department shall, within fourteen days after receiving the notice, submit to the responsible administrator who furnished the notice a statement with any information that the department deems to be relevant about the effect of the proposed short subdivision upon the legal access to the state highway, the traffic carrying capacity of the state highway and the safety of the users of the state highway.
RCW 58.17.155