What are water quality standards and who sets them?

Water quality standards protect public health by setting limits on contaminants in drinking water. Understanding these standards helps you know what we do to keep your water safe.

The EPA’s role:

The U.S. Environmental Protection Agency (EPA) establishes and enforces national drinking water standards under the Safe Drinking Water Act (SDWA). This federal law, enacted in 1974 and regularly updated, is the foundation of safe drinking water protection in the United States.

Types of standards:

Primary Standards (Maximum Contaminant Levels - MCLs):

• Legally enforceable standards that protect public health
• Set limits for over 90 contaminants including:
  • Microorganisms (bacteria, viruses)
  • Disinfectants and disinfection byproducts
  • Inorganic chemicals (lead, copper, arsenic)
  • Organic chemicals (pesticides, industrial compounds)
  • Radionuclides

Secondary Standards:

• Non-enforceable guidelines for contaminants that affect taste, odor, or appearance
• Include iron, manganese, pH, and hardness
• Not health hazards but we work to minimize these for customer satisfaction

Treatment Technique Requirements:

• Specific treatment processes we must use for certain contaminants
• Examples include filtration and disinfection requirements

What we do to meet EPA standards:

• Regular testing - We test for over 90 EPA-regulated contaminants on schedules ranging from monthly to every few years, depending on the contaminant
• Treatment processes - We operate EPA-approved water treatment systems to remove or reduce contaminants
• Monitoring and reporting - We continuously monitor water quality and report results to state and federal authorities
• Corrective actions - If any contaminant exceeds EPA limits, we must take immediate corrective action and notify customers

State oversight:

Our state regulatory agency oversees our compliance with EPA standards and may set additional requirements. State regulators review our testing results, inspect our facilities, and ensure we meet all federal requirements.

Public transparency:

EPA regulations require us to:

• Publish an annual Consumer Confidence Report (CCR) by July 1st each year
• Notify customers if we violate any drinking water standard
• Make water quality information available to the public
• Respond to customer inquiries about water quality

How standards are updated:

The EPA regularly reviews and updates standards based on the latest scientific research. When new contaminants of concern are identified, the EPA evaluates whether to establish new regulations.

Your right to know:

You have the right to know about the quality of your drinking water. Our annual water quality report provides detailed information about:

• Our water source
• All detected contaminants and their levels
• Compliance with EPA standards
• Health effects information

If you have questions about water quality standards or our compliance, please contact our office. For information about how to know if your water is safe, see How do I know if my water is safe to drink?. For concerns about water quality, see What should I do if I’m concerned about my water quality?. We’re committed to transparency and providing you with safe, reliable drinking water.