Wash. Rev. Code § 8.20.150
No corporation authorized by law to condemn property for public use, which has heretofore entered or shall hereafter enter upon property for a public use with the consent of the record owner or the person or corporation in possession, shall be ousted from such possession or prevented from continuing the putting of such property to public use if before entry of judgment of ouster it shall institute proceedings in condemnation to acquire such property for public use, and shall thereafter prosecute the same in good faith and pay any compensation which may be awarded therein.
RCW 8.20.150
Severability-1927 c 219: "If any section, provision or clause in this act be adjudged invalid the remainder of the act shall nevertheless remain valid." [ 1927 c 219 s 4.] This applies to RCW 8.20.150 through 8.20.170.