WAC 468-30-100
WAC 468-30-100. Policy relative to the installation of signs and markings on state highway rights of way
No permits shall hereafter be issued for the installation of signs and markings other than traffic control signs and state historical markers on state highway rights of way. Traffic control signs shall be consistent with the manual on Uniform Traffic Control Devices for Streets and Highways, as modified and adopted by the department of transportation.