Semiahmoo Spit is a low depositional feature rising approximately two meters above mean high water. Its low undulating sandy surface is covered with beach and grass scattered trees.
Coastal Processes of the Whatcom County Mainland (dnr.wa.gov)Numerous natural erosional and depositional processes operate upon shorelines to create a diversity of coastal landforms. Waves are among the most important causes of this diversity as they remove, build, and shape beaches and sea cliffs.
