Potentiometric surface of the Upper Floridan Aquifer, west-central Florida, September 1987

The potentiometric surface in the Upper Floridan aquifer was mapped by determining the altitude of water levels in a network of wells and is represented on maps by contours that connect points of equal altitude. Maps of the potentiometric surface of the Upper Floridan aquifer in west-central Florida are prepared semiannually by the U.S. Geological Survey. Maps for May and September show, respectively, the potentiometric surface of the normally expected annual low and high water level conditions. Potentiometric surface maps have been prepared for January 1964, May 1969, May 1971 to 1974, and for each May and September since 1975. The potentiometric surface of the Upper Floridan aquifer is shown for September 1987. Most of the water level data were collected by the U.S. Geological Survey during the period of September 14-18. Supplemental data were collected by other agencies and companies. This map represents water level conditions near the end of the summer rainy season when groundwater withdrawals for agricultural use are low and therefore, when the potentiometric surface is near its highest level for the year. (See also W88-03126) (Lantz-PTT)