Washington Revised Code Title 36. Counties § 36.56.010. Assumption of rights, powers, functions, and obligations authorized

Any county with a population of two hundred ten thousand or more in which a metropolitan municipal corporation has been established pursuant to chapter 35.58 RCW with boundaries coterminous with the boundaries of the county may by ordinance or resolution, as the case may be, of the county legislative authority assume the rights, powers, functions, and obligations of such metropolitan municipal corporation in accordance with the provisions of *this 1977 amendatory act. The definitions contained in RCW 35.58.020 shall be applicable to this chapter.