Risk Management to Provide Safe Drinking Water

Abstract

For the last 100 years, drinking water utilities in the United States (U.S.) have played a major role in protecting public health through the reduction of waterborne disease. For example, in the 1880s for one year, the typhoid death rate was 158 deaths per 100,000 in Pittsburgh, Pennsylvania, but by 1935, the typhoid death rate had declined to 5 per 100,000 (Clark, et al., 1991). These reductions in waterborne disease outbreaks were brought about by the use of sand filtration, disinfection and the application of drinking water standards. Despite this excellent record, occasional drinking water quality problems are a reminder of the need for constant vigilance. For example, in 1993, Milwaukee, Wisconsin suffered a Cryptosporidiosis outbreak, in which it was estimated that over 400,000 people were ill and an estimated 75-100 immune compromised people died (Blair, 1994). In July of 1993, Manhattan, New York was placed on a boil water order, as was Washington, DC in December of 1993. Both systems experienced microbial maximum contaminant level violations under the U.S. Safe Drinking Water Act (SDWA). In 1974, the U.S. Congress passed the Safe Drinking Water Act, which established the first set of national drinking water standards. The Act was amended in 1986 and again in 1996 to address the concerns that were not adequately addressed in the SDWA of 1974. Promulgation of many of the rules and regulations established under the Act will require extensive research in the areas of risk assessment, health effects, exposure and risk management.