Wash. Rev. Code § 70A.210.060
The proceeds of any bonds heretofore or hereafter issued in conformity with the authority of this chapter, together with interest and premiums thereon, and any revenues used to pay or redeem any of such bonds, together with interest and any premiums thereon, shall be separate trust funds and used only for the purposes permitted herein and shall not be considered to be money of the municipality. The services of the treasurer of a municipality, if such treasurer is or has been used, were and are intended to be for the administrative convenience of receipt and payment of nonpublic moneys only for which reasonable compensation may be charged by such treasurer or municipality.
RCW 70A.210.060
Port districts-Pollution control facilities or other industrial development-Validation: RCW 53.08.041.