A spit is formed due to the process of the long shore drift, the waves approach the beach in the direction of the prevailing winds, this causes the sediment to be pushed up the beach at an angle. The backwash then brings the sediment back down the beach vertically under gravity, this causes sediment to move a long the beach.When it reaches a river estuary, the sediment can no longer be transported so loses energy and is deposited. This accumulates over time and the feature extends into the sea. If the winds change direction, a recurved tip is formed. Behind the spit, a salt mash commonly forms due to the protected bay behind the sand bar.