Hydraulic and salinity characteristics of the tidal reach of the Peace River, southwestern Florida

Water-Resources Investigations Report 88-4162

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The tidal reach of the Peace River in southwestern Florida extends about 26 miles upstream from Charlotte Harbor and is characterized by flow-direction reversals, low velocities, and salinity gradients that vary with freshwater inflow, tides, and wind. Flow reversals generally occur on each tide throughout most of the tidal reach, their upstream limit determined primarily by freshwater inflow and tide. Flow reversals occur at river mile 18.9 whenever freshwater inflows are less than about 1,000 cu ft/sec. Velocities were less than 0.3 ft/sec more than half the time at river mile 18.9. The volume of the flood and ebb tidal flows in the midreach of the tidal river (mile 11.5) on July 12-13, 1984, was about five times the volume of flood and ebb tidal flow near the upstream end of the tidal reach July 10-11, 1984 (mile 18.9). Salinity varied along the 26-mile river reach, across channel and with depth, depending upon complex patterns of flow, freshwater runoff, wind, tide, and salinity in Charlotte Harbor. Daily variations in salinity increased downstream and variations were larger near the surface than near the bottom. Regression analysis indicated that the location of the 0.5 ppt salinity will move upstream more than 2 river miles if low flows are reduced by 50%. Freshwater flushing of the lower 20-mile tidal reach, approximated from freshwater replacement time, varied from about 2 days during heavy freshwater runoff to 40 days during extreme low flows. (USGS)

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USGS Numbered Series
Hydraulic and salinity characteristics of the tidal reach of the Peace River, southwestern Florida
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Water-Resources Investigations Report
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Dept. of the Interior, U.S. Geological Survey ; Books and Open-File Reports [distributor],
v, 37 p. :ill. ;28 cm.