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S.E. Henderson

Publications and source records attributed to S.E. Henderson.

5 recordsLinked to original sources
USGS1989

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

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)

Water-Resources Investigations Report↗
USGS1986

Hydrology of Hunters Lake, Hernando County, Florida

The size and shape of Hunters Lake, Florida has been significantly altered by development of the surrounding Spring Hill residential community. The lake is the largest in Hernando County, enlarged by lakeshore excavation and connection to nearby ponds to an area of 360 acres at an average stage of 17.2 ft above sea level. Hunters Lake is naturally a closed lake, but development of Spring Hill has resulted in a surface water outflow from the lake in its southwest corner. Inflow to the lake could occur on the east side during extreme high-water periods. The karst terrain of the Hunters Lake area is internally drained through permeable soils, depressions, and sinkholes, and natural surface drainage is absent. The underlying Floridan aquifer system is unconfined except locally near coastal springs. Flow in the groundwater system is to the west regionally and to the southwest in the immediate area of Hunters Lake. Water level gradients in the groundwater system increase from 1.4 ft/mi east of the lake to about 8 ft/mi southwest of the lake. Hunters Lake is hydraulically connected to the groundwater system, receiving groundwater on the northeast side and losing water to the groundwater system on the southwest side. This close relationship with the groundwater system is demonstrated by graphical and numerical comparison of Hunters Lake stage with water levels in nearby groundwater sites. During 1965-84, the stage of Hunters Lake fluctuated between 12.48 and 20.7 ft above sea level. Because area lakes are all directly affected by groundwater levels, they also show a close relationship with water levels in Hunters Lake. Analysis of water quality data for Hunters Lake indicates that the water of the lake is a soft calcium bicarbonate type with ionic concentrations higher than in water from nearby shallow wells and lower than in water from the Upper Floridan aquifer. Samples collected in 1981-1983 indicate slightly higher levels of ionic concentration than in 1965-66. Distribution of specific conductance readings throughout the lake and water samples and specific conductance from upgradient sites indicates an inflow of more mineralized water into the northern part of the lake. Concentrations of nutrients, carbon, and phytoplankton in Hunters Lake are typical of lakes in this area of west-central Florida. (Lantz-PTT)

Water-Resources Investigations Report↗
USGS1985

Hydrology of Lake Carroll, Hillsborough County, Florida

Lakeshore property around Lake Carroll has undergone extensive residential development since 1960. This development increased the lake shoreline, altered surface water flow to and from the lake, and may have affected lake-stage characteristics. Some areas of the lake were dredged to provide fill material for lakefront property. Water-balance analyses for 1952-60, a predevelopment period, and 1961-80, a period of residential development, indicate that both net surface water flow to the lake and downward leakage from the lake to the Floridan aquifer were greater after 1960. These changes were due more to changes in the regional climate and related changes in ground-water levels than to changes associated with residential development. Results of water quality analyses in 1980-81 are within State limits for surface waters used for recreation and wildlife propagation. (USGS)

Water-Resources Investigations Report↗