Wash. Rev. Code § 53.46.040
None of the obligations of each port district which has been consolidated shall be affected by the consolidation, and taxes and assessments for payment of such obligations shall continue to be levied and collected in respect to property in such former port district notwithstanding the consolidation. The port commission of the port district resulting from the consolidation shall have all the powers possessed at the time of the consolidation by the port commission of each port district which has been consolidated, to levy or collect taxes or assessments in respect to property in such former port district, for payment of such obligations. While any such obligations remain outstanding, funds subject to such obligations shall be kept separate.
RCW 53.46.040