Wash. Rev. Code § 35A.11.030
Powers of eminent domain, borrowing, taxation, and the granting of franchises may be exercised by the legislative bodies of code cities in the manner provided in this title or by the general law of the state where not inconsistent with this title; and the duties to be performed and the procedure to be followed by such cities in regard to the keeping of accounts and records, official bonds, health and safety and other matters not specifically provided for in this title, shall be governed by the general law. For the purposes of this title, "the general law" means any provision of state law, not inconsistent with this title, enacted before or after the passage of this title which is by its terms applicable or available to all cities or towns.
RCW 35A.11.030