From May 1975 through May 1976, water levels in the Floridan aquifer through most of north and central peninsular Florida declined 2 to 4 feet, on the basis of water-level measurements in 664 wells. These 664 were selected from a network of about 2,100 observation wells for which water-level measurements are in the files of the Geological Survey.
Hydrographs of 60 wells show that the downward trends of groundwater levels continued in areas of heavy pumping and in some areas not affected by pumping. In west-central Polk County, the most notable area of pumping, levels in the Floridan and other aquifers declined to new record lows in 1975 but recovered 3 to 6 feet in 1976. In north Florida where fluctuations of ground-water levels are primarily influenced by changes in stage of the Suwannee River, levels declined 18 and 23 feet in Suwannee and Hamilton Counties. In northwest Florida, declines in level in the sand-and-gravel aquifer ranged from less than 1 foot to 2 feet. In Nassau County, in Northern Brevard County, and at Stuart in Martin County--in the northeastern, eastern, and southwestern coastal parts of the State--levels declined to new record lows also.
