Drinking water Technology, Eawag, developed a method by which hazard maps could be produced for geogenic toxic substances in groundwater. This provides an efficient way of determining which wells should be tested. Parameters for drinking water quality typically fall within three categories: Physical and chemical parameters include heavy metals, trace organic compounds, total suspended solids (TSS), and turbidity. Microbiological parameters include Coliform bacteria, "E. coli", and specific pathogenic species of bacteria (such as cholera-causing "Vibrio cholerae"), viruses, and protozoan parasites. Chemical parameters tend to pose more of a chronic health risk through buildup of heavy metals although some components like nitrates/nitrites and
Drinking water may have total daily water needs of or more. The European Food Safety Authority recommends per day for adult women and per day for adult men. In the United States, the reference daily intake (RDI) for total water is per day for human males older than 18, and per day for human females older than 18 which includes drinking water, water in beverages, and water contained in food. An individual's thirst provides a better guide for how much water they require rather than a specific, fixed quantity. Americans, on average, drink of water a day and 95% drink less than