In carrying out any of the foregoing powers, or any powers possessed by said district, it shall have the right of eminent domain to acquire any property or rights or interest therein, within or outside of the district, necessary for the use of such district for the construction and maintenance of any ditches, drains, dikes, dams, spillways, outlets, necessary appliances and structures in connection with the operation, alteration, enlargement, extension, or protection of its drainage system. The procedure for exercising the right of eminent domain shall be that provided by law for private corporations.
RCW 85.06.690
Eminent domain by corporations generally: Chapter 8.20 RCW.