In so far as this chapter relates to cities of the second-class, this chapter shall not be deemed to be exclusive or as repealing or superseding any existing law relative to such cities, covering any subject covered by this chapter, but as to such cities, this chapter shall be construed as conferring additional powers and additional remedies, to those now provided by law.
RCW 8.12.560
Second-class cities, specific powers enumerated: RCW 35.23.440(45).