Longshore drift has a very powerful influence on the shape and composition of the coastline. It changes the slopes of beaches and creates long, narrow shoals of land called spits, that extend out from shore. Longshore drift may also create or destroy entire “barrier islands” along a shoreline. A barrier island is a long offshore deposit of sand situated parallel to the coast. As longshore drifts deposit, remove, and redeposit sand, barrier islands constantly change.
Tucker’s Island, New Jersey, is a barrier island that clearly illustrates how longshore drift and strong weather affect these transient sand deposits. The island was first settled in 1735. Since its settlement, residents have had to move the island’s lighthouse several times because the channels shifted constantly as a result of longshore drift. Eventually, they placed the lighthouse on high ground at the island's northern end.
Meanwhile, the inlet north of Tucker’s Island—Beach Haven inlet—was also effected by longshore drift. At times, the inlet was narrow or nonexistent and Tucker’s Island was attached to the nearby Long Beach Island. At other times, the inlet was wide, and Tucker’s Island was separated from Long Beach Island.
In 1924, in an effort to stop the beach erosion that was occurring on Tucker’s Island, experts installed jetties. They were initially successful in halting the erosion, but the jetties worked so well that the currents of Beach Haven inlet began to wash in the other direction—toward Tucker’s Island. As the inlet began to widen, the island then began to erode very quickly. By 1927, just three years after the jetties were installed, waves and longshore drift washed away most of the beach. Later that year, the remaining 300 yards of beach were washed away in a series of storms. Then, in a final dramatic display, the lighthouse fell into the sea!