Potentiometric surface of the Floridan aquifer system in the Suwannee River Water Management District, Florida, May 1985

The potentiometric surface map of the Floridan aquifer system in the Suwannee River Water Management District depicts the level to which water rose in tightly cased wells that tap the Floridan aquifer system in May 1985. The Floridan aquifer is the principal source of freshwater for north Florida. The surface was mapped by determining the altitude of water levels in a network of wells and is represented by contours that connect points of equal water level altitude. The Suwannee River Water Management District consists of about 7,600 sq mi, including all or part of 14 counties in north Florida.