Wash. Rev. Code § 53.36.060
The port commission of any port district may, by resolution, create an incidental expense fund in such amount as the port commission may direct. Such incidental expense fund may be kept and maintained in a bank or banks designated in the resolution creating the fund, and such depository shall be required to give bonds or securities to the port district for the protection of such incidental expense fund, in the full amount of the fund authorized by the said resolution. Vouchers shall be drawn to reimburse said incidental expense fund and such vouchers shall be approved by the port commission. Transient labor, freight, express, cartage, postage, petty supplies, and minor expenses of the port district may be paid from said incidental expense fund and all such disbursements therefrom shall be by check of the port auditor or such other officer as the port commission shall by resolution direct. All expenditures from said incidental expense fund shall be covered by vouchers drawn by the port auditor and approved by the manager or such other officer of the port district as the port commission may by resolution direct. The officer disbursing said fund shall be required to give bond to the port district in the full authorized amount of the said incidental expense fund for the faithful performance of his or her duties in connection with the disbursement of moneys from such fund.
RCW 53.36.060