The bill amends RCW 36.70A.536 to facilitate the development of middle housing in unincorporated areas of Washington State. It allows counties that are required or choose to plan under RCW 36.70A.040 to authorize middle housing types on parcels that permit single-family residences. The bill stipulates that no more than four residential units may be authorized per lot in both limited areas of more intensive rural development and designated urban growth areas. Additionally, it mandates that development regulations for middle housing cannot be more restrictive than those for detached single-family residences and must include provisions for public sewer services.

Key provisions include that middle housing must be served by a publicly owned sanitary sewer system or a large on-site sewage system in rural counties, and by a publicly owned sanitary sewer system in nonrural counties. The bill also ensures that middle housing in designated urban growth areas must be served by water and sewer services. Definitions for "rural county" and "large on-site sewage system" are provided to clarify the terms used in the legislation. Overall, the bill aims to promote the development of middle housing while maintaining certain regulatory standards.

Statutes affected:
Original bill: 36.70A.536
Substitute bill: 36.70A.536