FLORIDA GEOLOGICAL SURVEY


areas, similar in other respects, would indicate the relative amount
of water recharged to the aquifers.
 Table 7 shows that the total surface runoff during July, August,
and September 1960 from Pony Creek, a basin located on the Polk
piezometric high, was about 6 inches more than that from Horse
Creek, a basin located downslope from the Polk high, although the
rainfall on the Pony Creek basin was about 7 inches less. This
indicates a smaller ground-water storage capacity in the Pony
Creek basin than in the Horse Creek basin. Table 14 shows that
during the years 1959-61 surface runoff from the eastern basins,
which include the Polk high, was nearly the same as that from the
western basin although the rainfall was less. The conclusion derived
from comparing the data shown in Table 14 is that the rate of
ground-water recharge on the Polk high is about the same as that
in an area downslope from the Polk high.
 Ground-water outflow from the Green Swamp area is almost
 entirely via the Floridan aquifer. The net outflow over a significant
 period of time is approximately equivalent to the average amount
 of recharge to the aquifer during the period if there were no
 appreciable change in ground-water storage. Table 14 shows that
 the outflow is about 5 inches per year from the eastern part of the
 Green Swamp area and about 3 inches per year from the western
 part. Therefore, this infers that the eastern part contributes about
 2 inches more recharge to the Floridan aquifer. The net ground-
 water outflow from the Polk piezometric high (table 16) was
 estimated to range from 181 to 258 cfs or about 3 to 4.2 inches
 per year. Part of the outflow discharges into streams and swamps
 in the western part of the Green Swamp area so that the net
 amount that leaves as ground-water outflow probably ranges from
 112 to 169 cfs, or about 1.8 to 2.6 inches per year (table 17).
 Mineral content and calcium carbonate saturation with respect
 to calcite in water in the Floridan aquifer implies that recharge is
 about the same in the Green Swamp area as in other parts of central
 Florida. The presence of low mineral content in water in the
 interior of central Florida and high mineral content in water toward
 the coasts (figs. 44 and 45) suggests a general movement of water
 from the interior to the coasts. A comparison of the degree
 (percentage) of calcium carbonate saturation of water with
 respect to calcite in the Floridan aquifer throughout central Florida
 shows that under-saturation occurs throughout much of central
 Florida (fig. 43). Hem (1961, p. C-15) states that the degree of


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