REPORT OF INVESTIGATIONS No. 42


:radients and for future hydraulic gradients. The vertical
permeability computed from the movement of 5 inches of water a
year through the 15 feet of aquiclude with a head difference of 2
feet is about 0.003 gpd/ft2.
 During a wet period (November 1959), the average yearly
seepage from the eastern part of the area was determined to be
about 5 inches (table 14) when the level of Lake Lowery was about
134 feet and the piezometric surface was about 132 feet. During
a dry period (May 1962), the indicated yearly seepage from Lake
Lowery was about 21 inches when the level of Lake Lowery was
about 128 feet and the piezometric surface was about 120 feet. If
during May 1962 the water level in the Lowery pool had been
maintained at about 133 feet, the resulting gradient (13 feet)
would cause a yearly seepage rate of about 34 inches which is 60
percent greater than that computed for May 1962.
 The piezometric surface will decline progressively in response
to increased pumping in the populated and industrialized areas
south of Green Swamp (see fig. 37). Therefore, maintaining high
water levels in the southeastern part of the Green Swamp area will
make additional water available for future recharge.

 SIGNIFICANCE OF THE HYDROLOGY OF THE AREA

 The Green Swamp area is unique because it is a headwaters
area for five major rivers and for part of the Floridan aquifer. The
proximity of the headwaters of the streams and their interconnec-
tions by swamps at relatively high elevation suggest that the area
can be used effectively for flood control and water conservation.
Because of the high piezometric surface, Stringfield (1936) and
others have inferred that high rates of recharge for the Floridan
aquifer occur on the Polk high in the Green Swamp area and that
ground water flows outward in all directions from the area. In
order to meet the demands of present and future water-use and
for flood prevention, a water-management plan was proposed to
utilize the Green Swamp area for impoundment of flood waters
and for increasing the amount of recharge to the Floridan aquifer.
Thus, the significance of the hydrology of this area in relation to
central Florida has been appraised on the basis of the findings of
this investigation.
 In general, with other water-budget factors being equal, surface
runoff would be low in areas where high rates of ground-water
recharge occur. Therefore, comparison of streamflow from two


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