RCW 35.44.140

All lands held or owned by any county in fee simple, in trust, or otherwise within the limits of a local improvement district or utility local improvement district of a city or town shall be assessed and charged for their proportion of the cost of the local improvement in the same manner as other property in the district and the county commissioners are authorized to cause the assessments to be paid at the times and in the manner provided by law and the ordinances of the city or town. This section shall apply to all cities and towns, any charter or ordinance provision to the contrary notwithstanding.