The EPA has revised its approach to regulating “forever chemicals” in drinking water, easing restrictions on some compounds while maintaining stricter standards for others, raising questions about the balance between public health protection and water utility operational realities.

At a Glance

• EPA maintains strict limits on two key PFAS chemicals while relaxing standards for others
• National Primary Drinking Water Regulations (NPDWRs) are legally enforceable standards protecting public health
• National Secondary Drinking Water Regulations (NSDWRs) serve as non-enforceable guidelines for aesthetic water qualities
• States can choose to adopt secondary standards as enforceable regulations
• The decision affects water treatment facilities nationwide that must comply with federal standards

Understanding Drinking Water Regulations

The Environmental Protection Agency’s regulatory framework for drinking water operates on two distinct levels. National Primary Drinking Water Regulations (NPDWRs) establish legally enforceable standards designed to protect public health by limiting contaminants in drinking water supplies across America. These primary regulations represent the foundation of federal water quality control and compliance is mandatory for water utilities and treatment facilities nationwide.

In contrast, National Secondary Drinking Water Regulations (NSDWRs) function as non-enforceable guidelines addressing contaminants that affect cosmetic or aesthetic qualities of water, including taste, odor, and color. While not federally mandated, states retain the option to adopt these secondary standards as enforceable regulations within their jurisdictions, creating potential variations in water quality requirements across different states.

It’s #WorldWaterDay! Did you know 92% of populations served by community water systems meet all health-based standards all the time? We work in partnership with states, local communities & drinking water systems to ensure safe drinking water nationwide. https://t.co/3rnM0FzsKG pic.twitter.com/yZlgHD22qn

— U.S. EPA Water (@EPAwater) March 22, 2020

PFAS Regulation Changes

The recent EPA decision to revise standards for per- and polyfluoroalkyl substances (PFAS), commonly known as “forever chemicals,” marks a significant shift in regulatory approach under the current administration. The original federal standards established under the Biden administration aimed to mitigate health risks associated with these persistent environmental pollutants that have been linked to various health concerns including cancer, reproductive issues, and immune system dysfunction.

This regulatory adjustment maintains stringent thresholds for two specific PFAS chemicals while loosening standards for others. The revision acknowledges the challenges water utilities face in detecting and removing these substances at extremely low concentrations, while also attempting to maintain adequate public health protections. Water treatment facilities nationwide must now adapt their operations to meet these modified requirements.

PFAS are among the most toxic chemicals known—and their presence in our drinking water is unacceptable. 

The Trump EPA’s rollback of key regulations puts public health at risk when we should be working to eliminate these dangerous contaminants.https://t.co/YYJNqs37ur

— Senator Pete Harckham (@SenatorHarckham) April 10, 2025

Special Notice Requirements and Secondary Contaminants

Among the EPA’s specific regulatory requirements is a special notice provision for fluoride exceedance. Water systems must issue a public notice within 12 months if fluoride levels exceed the secondary standard of 2.0 mg/L. This requirement demonstrates how even secondary standards can carry compliance obligations despite their generally non-enforceable status. The attention to fluoride reflects ongoing debates about its optimal concentration in drinking water.

The EPA has established secondary drinking water standards for fifteen specific contaminants including aluminum, chloride, copper, iron, manganese, pH, sulfate, and total dissolved solids. Each contaminant has designated acceptable ranges related to aesthetic effects rather than direct health impacts. These guidelines help water utilities deliver palatable water while allowing operational flexibility compared to the more rigid primary standards that govern health-related contaminants.

Future Regulatory Considerations

The EPA maintains a Contaminant Candidate List (CCL) for unregulated drinking water substances that may require future regulation under the Safe Drinking Water Act. This watchlist serves as an early warning system for emerging contaminants of concern, allowing the agency to monitor scientific research and occurrence data before deciding whether formal regulation is warranted. The evolving understanding of PFAS has highlighted the importance of this regulatory pipeline.

The recent modifications to PFAS standards exemplify the delicate balance regulators must strike between protecting public health and acknowledging practical implementation challenges. Water utilities across the country, particularly smaller systems with limited resources, have expressed concerns about compliance costs associated with detecting and treating contaminants at extremely low concentrations. These economic realities influence regulatory decisions alongside scientific health assessments.

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