Figure 6. Groundwater movement in the Florida Keys is quite different than most coastal systems. Groundwater and surface waters continuously interact due to the porous nature of the water table aquifer. When tides are high in the Atlantic (top), Atlantic surface water is pushed into the subsurface and groundwater flows toward Florida Bay. When tides are low (bottom), groundwater flows toward the ocean. This continual sloshing of groundwater controls the overall path of injected wastewater and septic effluent in the subsurface, thus increasing the possibility of surface water contamination.
Credit: Robert Celander, FSU Research in Review, 1999