The bill introduces new requirements for cities and code cities in Washington regarding the designation of historic landmarks. Specifically, it mandates that cities must adopt or amend their development and zoning regulations to comply with these requirements within one year of the bill's effective date. Notably, no property can be designated as a historic landmark if it is less than 40 years old or if such designation would restrict the use, alteration, or demolition of the property without the written consent of the property owner. If a city fails to comply with these requirements, the new regulations will supersede any conflicting local regulations.

Additionally, the bill reenacts and amends existing law to clarify that certain actions taken by cities to implement these new requirements are not subject to administrative or judicial appeals. This includes actions consistent with the new sections added to chapters 35.21 and 35A.21 RCW, which outline the conditions under which properties can be designated as historic landmarks. The bill aims to streamline the process of historic landmark designation while ensuring property owners' rights are protected.