Water resources data for the 1999 water year for Kentucky consists of records of stage, discharge, and water quality of streams and lakes; and water levels of wells. This report includes daily discharge records for 106 stream-gaging stations. It also includes water-quality data for 10 stations sampled at regular intervals. Ground-water levels are published for 6 recording and 14 partial record sites. Precipitation data at a regular interval are published for 1 site. Additional water data were collected at various sites not involved in the systematic data-collection program and are published as miscellaneous measurements and analyses. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Kentucky.