Wash. Rev. Code § 35.68.030
If all or any portion of the cost is to be assessed against the abutting property owner, or if the abutting property owner is required to construct the improvement, the resolution shall fix a time from and after its passage, and a place, for hearing on the resolution. The resolution shall be published for two consecutive weeks before the time of hearing in the official newspaper or regularly published official publication of the city or town and a notice of the date of the hearing shall be given each owner or reputed owner of the abutting property by mailing to the owner or reputed owner of the property as shown on the tax rolls of the county treasurer, at the address shown thereon a notice of the date of hearing, the mailing to be at least ten days before the date fixed for the hearing. If the publication and mailing is made as herein required, proof thereof by affidavit shall be filed with the city clerk, comptroller or auditor of the city before the hearing. The hearing may be postponed from time to time to a definite date until the hearing is held. At the time of hearing the council shall hear persons who appear for or against the improvement, and determine whether it will or will not proceed with the improvement and whether it will make any changes in the original plan, and what the changes shall be. This action may be taken by motion adopted in the usual manner.
RCW 35.68.030