Sammamish, WA Landscaping Rules: Artificial Turf (2026)

080(2) sets minimum unbuilt "yard" area for new residential development within Sammamish's shoreline jurisdiction: 45 percent of the lot in shoreline residential designations under subsection (c), and at least 60 percent of the lot area above the ordinary high water mark in urban conservancy designations under subsection (d). Both subsections define "yard" identically as any surface area that is not structured or hardened, and both expressly list what counts toward that yard percentage: landscaping, uncovered decks less than 18 inches above grade, or artificial turf.

The same two subsections carve out one exclusion: areas covered by pervious concrete or other similar hardscape materials do not count as yard, even though they are permeable. In practice, a shoreline homeowner can install artificial turf in place of natural lawn without losing credit toward the 45 or 60 percent yard requirement, but cannot substitute a pervious-paver patio for the same purpose. 08 SMC, since new residential development and normal appurtenances must be located to meet the applicable yard percentage as part of demonstrating no net loss of shoreline ecological function.

This artificial turf allowance is specific to the Shoreline Master Program; the reviewed sections of Title 21A do not contain an equivalent artificial-turf provision for lots outside shoreline jurisdiction.