The United States Environmental Protection Agency (U.S. EPA) generated the estimates in this report in response to legislative mandates in the Safe Drinking Water Act Amendments of 1996. These mandates require up-to-date information on water ingestion to identify subpopulations at elevated risk of health effects from exposure to contaminants in drinking water. The estimates also support characterization of health risks to sensitive populations from contaminants in drinking water. The estimates in this document characterize the empirical distributions of 2-day average per capita ingestion of water for specific subpopulations. Subpopulation estimates apply to demographic categories, but do not distinguish individuals with a history of serious illness or with lifestyles that effect water ingestion. Specifically, this report presents current estimates of per capita water ingestion generated from dietary and demographic data collected in a survey conducted by the United States Department of Agriculture (USDA) in 1994 through 1996 and 1998. In this survey, known as the Continuing Survey of Food Intakes by Individuals (CSFII), 2 nonconsecutive days of food ingestion data were collected from a sample of more than 20,000 individuals in the 50 states and the District of Columbia. Respondent information, in conjunction with food code, recipe, and nutrient data from USDA, provide the means to estimate per capita ingestion of plain drinking water (direct water) and water ingested indirectly.