Pasco, WA Fence Regulations: Retaining Walls (2026)

Pasco regulates retaining walls primarily through the adopted building code and its reduced-permit policy. Per the city's published guidance, retaining walls under four feet tall are exempt from a building permit. This mirrors the International Residential Code, which exempts retaining walls not over four feet in height measured from the bottom of the footing to the top of the wall, unless the wall supports a surcharge (an added load such as a slope, driveway or structure above it). A permit is therefore required for walls taller than four feet or any wall carrying a surcharge, and engineered plans are typically needed for those. Retaining walls also interact with fence rules: under PMC 25.180.050, where a fence sits along a common lot line, fence height is measured from the grade along that line or from the top of any structural retaining wall occurring at the lot line. That means a tall retaining wall topped by a fence can together exceed the standalone fence limits, so confirm the combined treatment with the city. Walls must also respect setbacks, drainage and utility easements, and they cannot be placed to obstruct the intersection sight-distance triangle. Verify the current adopted code edition and thresholds with Pasco's Building Division before construction.