Water-resources data for the 1972 water year for Louisiana, including records of streamflow or reservoir storage at gaging stations, partial-record stations, and miscellaneous sites, and records of water-quality data on the chemical and physical characteristics of surface water are given in this report. Records for a few pertinent gaging stations in bordering States are also included. The records were collected and computed by the Water Resources Division of the U.S. Geological Survey under the direction of Albert N. Cameron, district chief. These data represent that portion of the National Water Data System collected by the U.S. Geological Survey and cooperating State and federal agencies in Louisiana.