Glossary

A structure projecting out into the sea, usually at the mouth of a harbor or river intersecting the coast, for the purpose of protecting a navigation channel or harbor, or to influence water currents; often built in pairs along both sides of an entrance channel.

Generally, a structure on an open coast extending into a body of water; designed to prevent shoaling of a channel by littoral materials and to direct and confine stream or tidal flow; defined in the State Navigation Law as a structure located within the shorelines of a body of water for the purpose of controlling currents usually to prevent filling in of a channel. Jetties are built at the mouths of rivers or tidal inlets to help deepen and stabilize a channel.