Oversight of Public Water Systems

Issued Date
September 24, 2018
Health, Department of


To determine whether the Department of Health (Department) is providing effective oversight of the State’s public water systems to ensure water is suitable for people to drink. Our audit covered the period January 1, 2014 to March 26, 2018.


The U.S. Environmental Protection Agency (EPA) established the public water system (PWS) supervision program under the authority of the 1974 Safe Drinking Water Act (SDWA). Under SDWA, the EPA sets national limits on contaminant levels – referred to as Maximum Contaminant Levels, or MCLs – in drinking water in an effort to ensure that it is safe for human consumption, and has established regulations for more than 90 contaminants. SDWA allows states to establish and enforce their own standards, provided they are at least as stringent as the EPA’s. In New York, the Department oversees the delivery of drinking water to ensure it is suitable for consumption. This oversight includes efforts to ensure that PWSs comply with State Public Health Law and State Sanitary Code (Code) requirements as well as EPA requirements. The Department sets MCL limits and requires that PWSs monitor the water for them. MCL violations require a PWS to notify the public and take any corrective actions necessary to return to compliance. Whether a given contaminant in water poses a health risk depends on its type, concentration level, and amount of exposure. Department district offices and local health departments (for purposes of this report, we refer to the Department district offices and local departments collectively as “Offices”) conduct the day-to-day oversight of PWSs. Nearly 95 percent of State residents receive their drinking water from one of the 9,155 PWSs in operation in the State. From January 1, 2014 through September 19, 2017, there were 768 MCL violations involving 201 of these PWSs located in 47 counties across the State.

Key Findings

  • While the Department takes various actions to safeguard the quality of drinking water delivered to PWS customers, we identified opportunities for improved oversight, particularly regarding PWS compliance as well as system and procedural controls.
    • When MCL violations occurred, the Offices we visited did not always take appropriate and/or timely action to hold PWSs accountable for required follow-up, such as notifying the public. As a result, the Department has less assurance that PWSs are appropriately addressing these occurrences.
    • The Department continues to study emerging contaminants in drinking water in an effort to determine whether maximum limits and regulations are appropriate.

Key Recommendations

  • Ensure that safe drinking water is distributed to the public through a robust monitoring program that, at a minimum:
    • Directs Offices to follow Department procedures for initiating appropriate corrective action and to maintain adequate records;
    • Requires Offices to verify that PWSs have issued timely public notifications of MCL violations to consumers; and
    • Ensures Offices account for the status of all active MCL violations and associated compliance activities and take any necessary actions to bring them into compliance.
  • Prioritize actions to regulate emerging contaminants with known adverse health effects.

Brian Reilly

State Government Accountability Contact Information:
Audit Director: Brian Reilly
Phone: (518) 474-3271; Email: [email protected]
Address: Office of the State Comptroller; Division of State Government Accountability; 110 State Street, 11th Floor; Albany, NY 12236