Wash. Rev. Code § 87.22.070
At the time and place stated in the notice of said hearing, the court shall consider said petition and shall receive such pertinent evidence as may be offered in support thereof or against the same, shall enter a decree fully determining the maximum benefits received by and the irrigable acreage in, the several tracts of land involved as shown by the schedule and as prayed for in said petition. Said action shall be an equitable one in rem and the court shall have full authority to make and issue any and all necessary orders and to do any and all things proper or incidental to the exercise of its jurisdiction in this connection. At said hearing the matters set forth in said petition and accompanying schedule shall be presumed to be true and correct in the absence of sufficient evidence to the contrary.
RCW 87.22.070
Refunding bonds-Form-Manner of payment-Interest rate (decree may determine): RCW 87.22.150.