Public water supplies are strictly regulated for a host of contaminants.  The most stringent standards are those set by the U.S. Environmental Protection Agency and the California Department of Public Health, and public drinking water systems must ensure compliance with these standards at all times.
Contrary to standards, there are also two sets of goals that apply to various contaminants that may be found in drinking water supplies.  The goals can be either state or federal goals.  The goals are not enforceable, but they provide contaminant levels for which the water system operators should strive to meet.
California Health and Safety Code specifies that larger water utilities prepare a special report if any of their water quality measurements have exceeded any Public Health Goals (PHGs) set by the California Environmental Protection Agency, or any Maximum Contaminant Level Goals (MCLGs), the federal equivalent to PHGs.  During the three-year periods indicated, if a constituent was detected in the Escondido water supply at a level exceeding an applicable PHG or MCLG, the report provides the information required for our customers.