Wash. Rev. Code § 70.22.040
The secretary of health is authorized and empowered to receive funds from any county, city or town, municipal corporation, taxing district, the federal government, or any person, group or organization to carry out the purpose of this chapter. In connection therewith the secretary is authorized and empowered to contract with any such county, city, or town, municipal corporation, taxing district, the federal government, person, group or organization with respect to the construction and maintenance of facilities and other work for the purpose of effecting mosquito control or elimination, and any such county, city or town, municipal corporation, or taxing district obligated to carry out the provisions of any such contract entered into with the secretary is authorized, empowered and directed to appropriate, and if necessary, to levy taxes for and pay over such funds as its contract with the secretary may from time to time require.
RCW 70.22.040