Authorizing accessory dwelling units in rural areas.

HB 1010 allows rural counties in Washington to authorize detached accessory dwelling units (ADUs) - small secondary homes on the same lot as a primary residence - on any lot size, even where local zoning previously prohibited them. Key requirements include limiting ADUs to 1,296 square feet, ensuring water/sewage systems can handle added demand, prohibiting construction on closed water sources or agricultural land, and requiring exterior design to match the main home. The bill directly affects rural property owners seeking to build affordable housing options and counties managing land use planning. It aims to expand housing choices without counting new residents toward rural growth targets in county plans.