The county handles building permits for all unincorporated areas, while incorporated cities like Pasco, Connell, and Kahlotus maintain their own independent building and planning departments. Development in the county is subject to critical area ordinances, including flood hazard zones along the Snake and Columbia Rivers and specific irrigation district requirements.
How this fits with the state
The state authority here is Washington Department of Labor & Industries. The county file does not replace that — it adds the permit office, local overlays, and the actual filing path.