Resource Description 
Sarasota Bay has been called a lagoon, a neutral estuary, and a 
bay. It is located between Tampa Bay and Charlotte Harbor, the nation’s 
17th and 18th largest estuaries, respectively (Seaman 1988). It 
exemplifies a number of water bodies along the Florida and gulf coasts by 
its proximity to open, shallow waters; much greater width than depth; 
physical dominance by wind and tides rather than tributaries; and 
recreational uses (Estevez 1988). 
The bay area has a mean annual temperature and rainfall of 72.0°F 
and 54.6 inches of rain per year. Most of the rain (60%) falls between 
June and September (Walton 1988). The bay is approximately 20 miles long 
and has a mean depth of 5 ft. Deeper portions of the bay’s central basin 
are 8-10 ft deep, and Longboat Pass (between Longboat Key and Anna Maria 
Island) has a maximum depth of 27 ft. Extensive shallow areas bordering 
the bay are mudflats, seagrass beds, or wetlands. The bay is subject to 
a relatively low energy climate (Evans 1988). Winds vary to and from the 
gulf, except during winter frontal systems when northwest winds prevail. 
Tides are mixed diurnal and semidiurnal, with a mean and extreme range of 
1.3 and 2.1 ft, respectively (Goodwin 1988, Walton 1988). Average wave 
heights (on barrier beaches) are about 1 ft, and sediment transport is 
minimal (Evans 1988, Harvey 1982). 
Currents in the bay are tide and wind dominated, ranging between 
0.3ft/sec in open bay areas to 1.5 ft/sec within inlets. A nodal area-- 
or zone of little net water movement-- crosses the mid bay area in 
Manatee County (Walton 1988). Flushing time for the bay in general is 
estimated to be 2-15 days, although actual rates depend upon freshwater 
inflow (DeGrove and Mandrup-Poulsen 1984; Dendrou, Moore and Walton 
1983). Toward the east and north the bay’s watershed is bounded by the 
Braden and Manatee Rivers, respectively, which flow into Tampa Bay. 
Uplands within the watershed occupy twice the surface area (80 sq mi) of 
open bay waters (40 sq mi) and are drained by the Palma Sola, Bowlees 
Creek, Whitaker Bayou, Hudson Bayou, and Phillippi Creek basins. The 
Phillippi Creek basin is the area’s largest. Its impervious area 
increased from 15% in 1966 to 22% in 1988 and is expected to reach 24% by 
the year 2000. This trend is believed applicable for the watershed as a 
whole. Combined peak discharge of nonpoint sources to the bay area are 
about 13,560 cfs (for a 25 year, 24 hr event over the entire watershed) 
(Flannery 1988, Giovannelli 1988). Treated wastewater contributes another 
15-25 cfs, and there are no industrial discharges of consequence. 
Water quality is considered "good" for most parts of the bay*. In 
fact, all waters of the bay except for two small creek mouths are 
According to 305b summaries by the Florida Department of 
Environmental Regulation, using water quality (marine) and trophic state 
(aquatic) indices. 
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