On the Flushing of Tampa Bay

A high-resolution, three-dimensional coastal ocean circulation model is used to estimate the bulk residence time distributions for the entirety of Tampa Bay and for five of its sub-regions using an Eulerian passive tracer technique. With a resolution as high as 20 m, the model domain includes all of the important mass conveyances by the channels and inlets, plus the impediments to flow by bridge causeways and natural constrictions. The non-tidal circulation is found to be the primary agent for the flushing of Tampa Bay. Tides alone have a minor effect. Exceptions pertain to within a tidal excursion from the mouth of the bay and sub-regions with multiple inlets, where differential flows related to tidal phase differences aid in flushing. By resolving the main shipping channels, we also address the effect of channel deepening and widening on the flushing of Tampa Bay. Bulk residence time is found to decrease due to an increase in the non-tidal circulation.