Sammamish grading, drainage, and street standards
Site work in Sammamish needs a Clearing and Grading Permit or a Site Development Permit unless SMC 16.15.050 exempts it. The city caps cut and fill slopes at 2 horizontal to 1 vertical unless the Director approves, and work within critical areas or their buffers cannot be exempted, except on publicly owned land. The residential code exempts a wall of four feet or less that carries no surcharge, so a short wall on level ground is treated differently from one that holds fill or a structure.
Under the city’s Title 13 definitions, drainage review applies once new plus replaced impervious surface reaches 2,000 square feet, or land-disturbing activity reaches 7,000 square feet. Residential driveways in the street follow the 2016 Public Works Standards, which set a residential width of 10 to 24 feet on non-arterial streets and 20 to 24 feet on arterial streets, measured at the right-of-way or property line. The standards cap grade in the right-of-way at 15 percent.
Nearby, we also build in Redmond, Issaquah, Kirkland, and Woodinville, and we serve the rest of western Washington.
Sources we checked
Checked November 2026. Rules change, so we confirm the current requirements with the city before we start.