1 Circulation Patterns at Tidal Inlets

interpreting horizontal circulation patterns at inlets. BACKGROUND: Tidal inlets provide a conduit for water exchange between the ocean and coastal bays, lagoons, and estuaries. They also serve as navigation routes for commercial and recreational vessels. The U.S. Army Corps of Engineers maintains Federal inlets on all coasts of the United States and its territories. The Corps manages inlets primarily by construction of jetties and by dredging. Jetties stabilize the entrance and the entrance channel, and they also protect vessels from waves as they travel between the surf zone and deep water. Tools for inlet management have become more sophisticated in recent years with advances in field instrumentation and computing capabilities. These improvements have yielded high-quality data and detailed calculations of inlet currents. Engineering problems that can benefit from interpretation and understanding of circulation patterns at inlets are prediction and prevention of scour, channel migration, and navigation safety. Circulation patterns are specific to each inlet, but certain properties are common to many inlets. Common properties include ebb or flood dominance, preferred channels on ebb and flood tide, eddy formation and migration, and jetty control on flow patterns. This CETN describes th