ABSTRACT

Turbidity in Tampa Bay was monitored for a 6-month period using a towable 1-meter optical transmissometer system (Hydro-Products Model 512T). The system provided for continuous chart readout and allowed short-term water-mass migrations to be quantitatively mapped.

Five major sources of turbidity were identified (1) resuspended bottom sediment, both naturally over shoals and artificially by dredging and other developmental activities, was the greatest source of turbid water; (2) suspended phytoplankton, seston, was important locally, especially in Hillsborough Bay, where the pollutional nutrient input is excessive and promotes plankton blooms. Other, less important sources of turbidity were from: (3) sewage outfalls and miscellaneous inputs related to urbanization; (4) river-borne tripton; and, (5) surf-generated fine debris. Transmission readings ranged from 80 percent in the open Gulf of Mexico to 0 percent in Hillsborough Bay.