The position of the saltwater-freshwater transition zone in the Floridan aquifer along coastal southwest Florida is depicted by the 250 milligram per liter line of equal chloride concentration in the upper producing zone of the aquifer. The line was interpolated from chloride concentration data for wells open to the upper producing zone of the aquifer and plotted on a map having a scale of 1:250,000. The line generally lies inland within 5 miles of the coast in areas extending from latitude 29 degrees in Citrus County southward to southern Hillsborough County. In Manatee and Sarasota Counties, the line generally lies with 2 miles of the coast, except in southern Sarasota County where it extends eastward along the Charlotte-DeSoto County line. Knowledge about the position and movement of the 250 milligram per liter line is significant in the effective management of the ground-water resources of coastal areas. The present position of the line will be used as a basis for detecting future movement of the saltwater-freshwater interface. (USGS)
Additional publication details
USGS Numbered Series
Position of the saltwater-freshwater interface in the upper part of the Floridan Aquifer, southwest Florida, 1979
3 maps :col. ;59 x 33 cm. and 25 x 14 cm. on sheet 74 x 97 cm. folded in envelope 31 x 23 cm.