Wash. Rev. Code § 36.94.320
In consideration of a transfer of property by a municipal corporation to a county in the manner provided in RCW 36.94.310 through 36.94.350, a county may assume and agree to pay or provide for the payment of all or part of the indebtedness of a municipal corporation including the payment and retirement of outstanding general obligation and revenue bonds issued by a municipal corporation. Until the indebtedness of a municipal corporation thus assumed by a county has been discharged, all property within the municipal corporation and the owners and occupants of that property, shall continue to be liable for taxes, special assessments, and other charges legally pledged to pay such indebtedness. The county may assume the obligation of causing the payment of such indebtedness, collecting such taxes, assessments, and charges and observing and performing the other contractual obligations of the municipal corporation. The legislative authority of the county may act in the same manner as the governing body of the municipal corporation for the purpose of certifying the amount of any property tax to be levied and collected therein, and may cause service and other charges and assessments to be collected from such property or owners or occupants thereof, enforce such collection and perform all other acts necessary to insure performance of the contractual obligations of the municipal corporation in the same manner and by the same means as if the property of the municipal corporation had not been acquired by the county.
When a county assumes the obligation of paying indebtedness of a municipal corporation and if property taxes or assessments have been levied and service and other charges have accrued for such purpose but have not been collected by the municipal corporation prior to such assumption, the same when collected shall belong and be paid to the county and be used by such county so far as necessary for payment of the indebtedness of the municipal corporation existing and unpaid on the date such county assumed that indebtedness. Any funds received by the county which have been collected for the purpose of paying any bonded or other indebtedness of the municipal corporation shall be used for the purpose for which they were collected and for no other purpose until such indebtedness has been paid and retired or adequate provision has been made for such payment and retirement. No transfer of property as provided in *this amendatory act shall derogate from the claims or rights of the creditors of the municipal corporation or impair the ability of the municipal corporation to respond to its debts and obligations.
RCW 36.94.320
*Reviser's note: For codification of "this amendatory act" [1975 1st ex.s. c 188], see Codification Tables.