RCW 28A.530.040

Whenever any bonds lawfully issued by any school district under the provisions of this chapter shall reach maturity and shall remain unpaid, or may be paid under any option provided in the bonds, the board of directors thereof shall have the power without any vote of the school district to fund the same by issuing bonds conformable to the requirements of this chapter and use the proceeds exclusively for the purpose of retiring and canceling such outstanding bonds as aforesaid, or the said directors in their discretion may exchange such refunding bonds par for par for such outstanding bonds.