Water-resources investigations of the U. S. Geological Survey include the collection of water quality data on the chemical and physical characteristics of surface- and ground-water supplies of the Nation. These data for the 1973 water year for the quality of surface waters in Florida are presented in this report. The data were collected by the Water Resources Division of the U. S. Geological Survey under the direction of Clyde S. Conover, District Chief, Florida District.