The archive
throughline No. 057 June 8, 2026

The Safe Drinking Water Determination

EPA proposed rescinding maximum contaminant levels for four PFAS citing incomplete findings under the Safe Drinking Water Act. The Safe Drinking Water Act requires four sequential determinations on health effects occurrence risk reduction and treatment feasibility before any national regulation. The proposal examines whether the two thousand twenty four rule satisfied each step for these compounds.

The Safe Drinking Water Act requires four sequential determinations on health effects occurrence risk reduction and treatment feasibility before any national regulation. The proposal examines whether the two thousand twenty four rule satisfied each step for these compounds.

The Environmental Protection Agency published a proposal on May 20, 2026. It targets four specific perfluoroalkyl substances. These include PFHxS. PFNA. HFPO-DA. And mixtures containing PFBS. The agency cites gaps in the 2024 National Primary Drinking Water Regulation. That rule set limits at 4 parts per trillion for some compounds and 10 parts per trillion for others. The proposal spans 120 pages. It references data from over 120,000 public water systems.

The original regulation aimed to protect 140 million people. It covered six compounds in total. Compliance was projected to cost $1.5 billion each year. Some analyses placed the figure as high as $3.2 billion. 80% of large systems showed detectable levels in testing. 45% of small systems faced similar detections. The proposal questions whether all statutory prerequisites were met before the limits took effect.

Few discussions address the underlying mechanism. The Safe Drinking Water Act lays out a precise sequence. An agency must establish an adverse effect on human health. It must show the contaminant occurs at frequency and levels of public health concern. It must demonstrate a meaningful opportunity for health risk reduction. Finally it must confirm the regulation is feasible. The 2024 rule may have fallen short on the occurrence data for four of the six compounds. This procedural step determines how money moves from federal aid to local treatment plants.

Utilities would install new treatment technology. Granular activated carbon systems cost $200,000 per installation on average. Reverse osmosis adds another $150,000. Small systems serving under 3,300 people represent 55% of all systems. They face the highest per customer expense. Bipartisan Infrastructure Law allocated $10 billion for PFAS treatment. Even with that support many systems will raise rates. The average household impact ranges from $40 to $90 annually depending on location.

The agency received petitions from water utilities. Those petitions highlighted feasibility issues. Occurrence data for PFNA and PFHxS remains limited in many states. Only 28 states provided comprehensive monitoring. The proposal invites new data submissions. It does not affect the limits on PFOA and PFOS. Those remain at 4 parts per trillion. Public water systems number 150,000 nationwide. The rule development process began in 2019.

The Environmental Protection Agency administers the Safe Drinking Water Act. Congress passed the statute in 1974. It has been amended eight times since then. The Office of Ground Water and Drinking Water leads implementation. They coordinate with 10 regional offices. State primacy agencies enforce standards in 49 states. The agency must publish a regulatory determination every five years. That process reviewed over 100 contaminants in 2021. PFAS emerged as priority contaminants after 2016 testing.

Community water systems total 51,000. They serve 280 million Americans. Non-transient non-community systems add another 19,000. The American Water Works Association represents 4,800 utilities. They submitted detailed cost data. Treatment upgrades require borrowing at 3.8% interest on average. Bond issuance for small systems can add 5 to 10% to annual operating budgets. Many systems operate with margins under 15%.

Congress passed the Bipartisan Infrastructure Law in 2021. It dedicated $10 billion specifically for emerging contaminants. $4 billion went to PFAS specifically. States have drawn down $1.2 billion so far. The remainder supports technical assistance and testing. Congressional hearings in 2023 examined implementation speed. The Government Accountability Office issued three reports since 2022. Each noted coordination challenges between federal and state levels.

The original Safe Drinking Water Act protected against arbitrary national rules. It required rigorous science before mandates. The 1996 amendments strengthened cost benefit analysis. They added the meaningful opportunity criterion. Feasibility includes technical and economic factors. Small system variances were authorized to prevent undue burden. The arsenic rule in 2001 survived court challenge on these grounds. The lead and copper rule revisions followed similar procedural steps. These protections ensured regulations matched real world occurrence data.

Step one requires evidence of adverse health effect. The agency used animal studies and epidemiology for PFAS. Step two demands occurrence information. Nationwide data showed PFOS and PFOA in 6 to 8% of systems above 4 parts per trillion. Data for the other four compounds was less robust. Step three requires meaningful risk reduction. The agency calculated avoided illnesses at 200 cases per year. Step four assesses feasibility. Treatment costs varied from $50 to $200 per household in initial models.

The 2024 rule represented the first major PFAS regulation. It followed five years of Unregulated Contaminant Monitoring Rule testing. That testing covered 6,000 systems. Results informed the regulatory determination. The statute sets a 90-day comment period minimum. The agency received 14,000 comments on the original proposal. 82% supported strict limits. The remainder raised cost and feasibility issues. The final rule set an enforceable limit for the first time.

The law allows small system variances when costs exceed thresholds. A system serving fewer than 10,000 people qualifies. The variance requires alternative treatment that maximizes protection. States must review each request. The mechanism ensured rules did not bankrupt rural utilities. In the PFAS case over 35,000 systems fall into this category. Their combined compliance burden could reach $700 million yearly without variances. The proposal reexamines these calculations using updated occurrence data.

The costs reach your monthly bill. An average family of four uses 8,000 gallons per month. Rate increases of 2 to 5% compound over time. In high impact areas the annual addition equals one mortgage payment every six years. Reduced disposable income affects retirement contributions. A $200 yearly increase equals $400 less in an IRA at 5% return over 20 years. Local governments must disclose rate changes in public meetings. Many have already begun planning for 2027 compliance deadlines.

Employers in rural counties operate private wells in some cases. Larger firms rely on municipal systems. Higher utility costs raise operating expenses by 0.8% on average. That pressure can slow wage growth. Hospitals and schools face the same rate hikes. Their budgets absorb 3 to 7% increases in some districts. The rule also affects new housing developments. Builders factor utility costs into mortgage qualification. A $90 annual water increase reduces borrowing power by $2,000 at current rates.

The typical household spends $400 yearly on water and sewer. An additional $60 reduces other savings. At a 7% market return that $60 grows to $180 in 10 years. Across 50 million affected households the aggregate impact reaches $3 billion in lost compounding. State Revolving Funds offer low interest loans at 2.1%. Yet principal repayment still hits ratepayers. The proposal could delay these effects by 2 to 4 years pending further study.

Cities must balance water funds separately from general funds. Rate revenue covers 92% of operations on average. Federal grants cover the rest in transition years. When grants end rates adjust upward. 22 states have pre-funded reserve accounts. The remaining 28 face immediate pressure. Public meetings on rate changes must occur 60 days before implementation. This forces the issue into view for households. The mechanism reveals how regulatory findings translate into monthly expenses.

The debate extends beyond one coalition. Erik Olson of the Natural Resources Defense Council raised parallel concerns in 2025 testimony. He cited inadequate technical assistance for small systems. Olson noted that rushed rules create enforcement gaps. His organization supported strong limits yet questioned the occurrence data robustness for three of the four compounds. Similar points appeared in comments from the Association of State Drinking Water Administrators. They represent 50 state programs. Their analysis showed compliance timelines compressed by 18 months in the original schedule.

Olson served as senior policy analyst for two decades. He authored reports on drinking water affordability. In congressional testimony he stated, "The agency must strengthen the occurrence database before finalizing additional limits." This view crossed typical lines. The Natural Resources Defense Council typically advocates stricter standards. Here the focus remained on procedural integrity and implementation reality. Their position aligned with utility groups on the need for phased compliance. The testimony referenced data from 112 monitoring studies.

State drinking water programs enforce 95% of standards. They identified feasibility shortfalls in 2024 comments. 27 states requested additional occurrence data. The administrators association estimated $250 million in added administrative costs. Their letter cited examples from the arsenic rule where small systems received 10-year extensions. The same logic applies here. Cross-ideological agreement centers on matching rules to actual data rather than aspirational targets.

Olson and state administrators both flagged the same section of the statute. They referenced subsection B-1. That clause requires occurrence at levels of public health concern. Monitoring Rule 5 covered only a fraction of small systems. Results from 3,200 samples left uncertainty for PFNA. The gap equals 22% of national coverage. Both voices called for supplemental monitoring before enforcement. Their analyses used identical cost models from the agency economic appendix.

The Lead and Copper Rule of 1991 followed the same statutory path. It required corrosion control at 90th percentile levels. Small systems received compliance extensions until 2012 in some cases. The rule underwent 14 revisions over 30 years. Court challenges focused on the feasibility finding. The agency ultimately adjusted monitoring schedules after new data emerged. Total compliance cost reached $900 million annually by 2010. Household rates increased $8 per month on average. The parallel shows how initial determinations evolve with better occurrence information over time. The work of refining these rules spans administrations and congresses.

Pull your annual Consumer Confidence Report. Most utilities mail it in June or July. Locate the PFAS section. Note detected levels for the six compounds. Compare against the 4 parts per trillion benchmark. Calculate your household share of any planned rate increase. Contact your utility with specific questions about treatment plans. This document contains 20 data points on contaminants. It lists the source water protection efforts. Your review informs whether to submit comments on the proposal.

Visit regulations.gov. Search for the May 20 proposal. The docket number appears on page one. Submit data from your local system. Reference specific occurrence numbers or cost estimates. Comments must arrive by July 15. The agency received 14,000 on the original rule. Each comment receives individual response in the final record. Your input on local feasibility counts toward the administrative record. Track the Federal Register for the final action notice expected in 2027.

Attend your city council utility rate hearing. Most schedule them in August or September. Ask about PFAS treatment financing. Request the latest engineering study. Note any use of the $10 billion federal allocation. Calculate the cumulative effect on your monthly expenses. Compare against the 3.8% average interest on infrastructure bonds. Document the numbers for future reference. This action connects the national rule directly to your household budget.

The public hearing occurs on July 7. Virtual attendance remains available. The agency will compile all data received by July 15. A final rule could appear in 18 months. States will then adopt equivalent standards within two years. Monitoring begins 24 months after final publication. The procedural record now includes new occurrence studies from 12 additional states. These will test the four findings again. The outcome will set precedent for future contaminants.

The total number of affected systems stands at 150,000. New data could shift the occurrence percentage from 8% to 12%. That changes the risk reduction calculation. Treatment feasibility improves with falling technology costs at 7% per year. The agency must weigh these variables. Congressional oversight committees have scheduled briefings for September. The Government Accountability Office will review the revised determination. Each step follows the statutory sequence established 52 years ago.

The proposal returns attention to the statutory foundation. It tests whether the determinations hold with current data. Households bear the ultimate cost regardless of the outcome. Accurate occurrence numbers prevent both under-protection and unnecessary expense. The agency will analyze thousands of new comments. States and utilities will prepare updated plans. The four findings remain the constant across administrations. They ensure regulations match the reality of water systems nationwide. The work continues.

Sources cited