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Regulatory and Security Requirements for Potable Water

Water Quality Control

  1. Suzanne Du Vall Knorr

Published Online: 15 JUL 2005

DOI: 10.1002/047147844X.wq586

Water Encyclopedia

Water Encyclopedia

How to Cite

Du Vall Knorr, S. 2005. Regulatory and Security Requirements for Potable Water. Water Encyclopedia. 2:343–350.

Author Information

  1. Ventura County Environmental Health Division, Ventura, California

Publication History

  1. Published Online: 15 JUL 2005


Potable water is drinking water that meets the requirements of the Safe Drinking Water Act (SDWA) or stricter state requirements. Water suppliers must provide an annual water quality report to their customers or a consumer confidence report as required in California. Primary drinking water standards require corrective action and public notification when exceeded. The water system must also notify customers when a secondary drinking water standard is exceeded, although corrective action is optional.

A Cryptosporidium outbreak in Milwaukee, Wisconsin, led to regulations requiring filtration to remove cysts. Between 1999 and 2000, 28 of 39 waterborne disease outbreaks were from groundwater sources. The federal Environmental Protection Agency (EPA) has proposed disinfection of groundwater. Recent focus on chemical contaminants involves methyl-t-butyl ether (MTBE) and perchlorate found in drinking water sources. EPA classified MTBE as an unregulated contaminant. The California Department of Health Services (CDHS) established primary and secondary maximum contaminant levels (MCL) for MTBE. EPA and CDHS have established advisory levels only for perchlorate.

Focus on intentional contamination led to two federal laws affecting water systems: the Homeland Security Act and the Public Health Security and Bioterrorism Preparedness and Response Act (Bioterrorism Act). The Homeland Security Act requires reporting potential threats to the Department of Homeland Security. The Bioterrorism Act requires that water systems serving more than 3300 people submit a vulnerability assessment to EPA, prepare an emergency response plan, and implement needed security upgrades.

Drinking water requirements change as science and technology advances and as agencies learn more about the health affects of waterborne contaminants. Ensuring a safe potable water supply requires vigilance. The goal of regulatory agencies and water purveyors is to ensure a safe and reliable drinking water supply.


  • drinking water;
  • potable water;
  • Cryptosporidium parvum;
  • Escherichia coli O157:H7;
  • perchlorate;
  • methyl-tertiary-butyl ether;
  • regulations;
  • laws;
  • safe drinking water act