Sand Bypass System

Sand Bypass System. Creating Balance. , There is an ocean current that moves sand parallel to the coast known as the "littoral drift" or "longshore current." Along most of coastal Delaware, this current moves in a northward direction. As it moves north, it moves sand. There is so much sand being moved that the "cape" at Cape Henlopen State Park is actually growing., Completion of the stone jetties in 1939 interrupted this natural flow of sand. As a result, the beach on the south side of the inlet grew, while the beach on the north side became "sand -starved.", To make up for this imbalance, a sand bypass system was constructed in 1990. The building located between the jetty and the public bathhouse is the pump-house that powers this system. A slurry of sand and water is vacuumed up from the south side of the inlet, pumped through a pipe that is affixed to the bridge, and is then deposited onto the beach on the north side of the inlet. This system operates from September to May each year, and although the amounts may vary, it is designed to pump 100,000 cubic yards of sand., [Captions:] , These photos show how littoral drift has changed the shape of Cape Henlopen over the years., The pump-house powers the bypass system that moves sand from the south side to the north side of the inlet.