The Florida Intracoastal Waterway (IWW) passes near many inlets where wave- and tide-generated currents entrain and transport some of the littoral sediments through the inlet and the rest to downdrift nearshore areas. These currents can move sediments inshore until flow velocities decrease below a critical value, at which point sediments fall out of suspension and can form shoals in the IWW and surrounding areas in the area of interest.

Over the course of several projects, the Florida Inland Navigation District retained Taylor Engineering to identify and analyze the existing features, wave climate, hydrodynamics, and sediment characteristics of the IWW near an inlet to determine whether any dredging efficiency management alternatives including IWW re-routing would reduce sediment inflow into IWW and thereby reduce the frequency and costs of IWW maintenance dredging. To complete the studies, Taylor Engineering measured flow velocity and water level to validate and apply a state-of-the-art modeling tool—the MIKE suite of hydrodynamic, spectral wave, particle tracking, sand transport, and morphology models—to evaluate the sediment transport mechanisms and alternatives to reduce sediment inflow into the IWW.

Study results show specific cases where IWW re-routing would require less dredging frequency, provide substantial annual cost savings in the maintenance dredging, and improve boat navigation safety.