Bandwidth:    Low     Medium     High

Almost all of the public water supplies in Pennsylvania provide water that is safe to drink. Incidents of drinking water contamination, however, have been reported in every state. The following statistics demonstrate the need for communities to protect their drinking water supplies from contamination (U. S. EPA, 1990a; U. S. EPA, 1990c):

  • More than 200 chemical contaminants have been identified in groundwater;
  • Some 52,181 cases of illness associated with groundwater contamination (mostly short-term digestive disorders) were reported between 1971 and 1985;
  • Seventy-four pesticides have been detected in the groundwater of 38 states;
  • Approximately 10 percent of public water supplies derived from groundwater exceed federal drinking water standards for bacteriological contamination; and
  • Pa. records show that more than 600,000 people in Pennsylvania have been affected by boil water advisories that were issued as a result of microbial contamination of drinking water.

This section discusses how drinking water can become contaminated, the sources of contamination and the potential effects on human health and local economies. It also presents an overview of initiatives designed to prevent drinking water contamination.