PFAS Capital Improvement Plan

PFAS Capital Improvement Plan: Strategies for Addressing Contamination and Ensuring Safe Water Supplies

Introduction

PFAS treatment is among the largest capital commitments many water utilities will make this decade, and it arrives with a fixed deadline. A PFAS Capital Improvement Plan is how a utility converts a compliance obligation into a funded, sequenced program: what gets built, in what order, paid for how, and finished by when. This article covers the components of such a plan, the timeline pressures that shape it, funding routes, and the cost drivers that are most often underestimated.

The plan sits within a broader management framework described in our guide to PFAS management best practices.

Understanding the Challenge

What are PFAS?

PFAS are a family of thousands of synthetic chemicals used since the mid-twentieth century for water- and grease-resistant properties in cookware, textiles, firefighting foams, and food packaging. Their persistence has led to widespread environmental contamination.

Health Risks

PFAS exposure has been linked to elevated cholesterol, thyroid effects, reproductive and developmental problems, and certain cancers including kidney and testicular cancer. National biomonitoring by the CDC has detected PFAS in the blood of the great majority of the U.S. population.

The Regulatory Deadline

EPA finalized enforceable drinking water limits in April 2024: 4.0 parts per trillion for PFOA and PFOS, with limits for PFHxS, PFNA, HFPO-DA, and a mixture hazard index, and compliance required by 2029. In May 2026, EPA proposed retaining the PFOA and PFOS limits while allowing systems to request an extension to 2031, and rescinding the other limits. As of September 2026 both remain proposals.

For capital planning, the practical reading is: assume the PFOA and PFOS limits stand, plan against the 2029 date, and treat any extension as contingency rather than as the schedule. The proposed extension requires a request to EPA rather than applying automatically.

Building the Plan

1. Characterization

Everything downstream depends on knowing what is in the water:

  • Full PFAS profile, not only the regulated compounds. Short-chain compounds frequently govern media life and therefore operating cost.

  • Source-by-source data, since concentrations often vary considerably between wells, which opens strategic options.

  • Water quality parameters affecting treatment — organic carbon, competing anions, iron and manganese, hardness.

  • Trend data, because concentrations can rise as precursors degrade.

2. Strategy Selection

Before committing to treatment, evaluate the alternatives: taking a contaminated source out of service, blending, developing a new source, interconnecting with a neighboring utility, or point-of-use treatment where the state permits it for small systems. For some utilities these are faster and cheaper than construction. Where treatment is the answer, that conclusion is more defensible for having been tested.

3. Pilot Testing

Pilot testing or rapid small-scale column tests on the actual source water produce the breakthrough data that sizing and operating cost estimates depend on. Skipping this stage is the most common cause of systems that cost far more to run than budgeted. Pilots take months, and they sit on the critical path.

4. Technology Selection

  • Granular Activated Carbon: The most widely installed option, effective for long-chain PFAS, with media replacement driven by breakthrough of the weakest-adsorbing compound present.

  • PFAS-Selective Anion Exchange: Longer run times at shorter contact times and smaller vessels, with better short-chain performance; resin is generally single-use.

  • Reverse Osmosis and Nanofiltration: Very high rejection across chain lengths, at the cost of energy, water loss, and a concentrate stream requiring management.

Conventional advanced oxidation does not remove PFAS and should not appear in the plan as a treatment option. Detailed design considerations are covered in our guide to PFAS system design.

5. Infrastructure Scope

Treatment vessels are rarely the whole job. Budgets should account for:

  • Buildings or enclosures, foundations, and site work

  • Pumping to overcome added headloss through treatment

  • Electrical and instrumentation

  • Pretreatment where iron, manganese, or solids would foul media

  • Backwash handling and, for membranes, concentrate management

  • Media handling access for change-outs

Cost Drivers Often Underestimated

  • Media replacement frequency, driven by the PFAS profile and background organic carbon, is the dominant operating cost for adsorptive systems and varies widely between sources.

  • Residuals disposal, which is becoming more expensive and more constrained as landfill and incineration options narrow. Spent media and concentrate carry long-term liability, reinforced by the designation of PFOA and PFOS as hazardous substances under CERCLA.

  • Staffing, since treatment that did not previously exist requires operator time, sampling, and reporting.

  • Monitoring, including compliance sampling and operational sampling between vessels.

  • Regulatory change, which may require additional capacity or different media within the asset’s life.

Phased Implementation

  1. Phase 1: Assessment and Interim Measures — characterization, strategy evaluation, pilot testing, and any immediate actions such as source management or blending that reduce exposure while longer-term work proceeds.

  2. Phase 2: Design, Funding, and Construction — the longest phase. Design, permitting, funding applications, procurement, and construction commonly take three to five years in total, which is why work starting now is already close to the compliance deadline.

  3. Phase 3: Operation and Optimization — commissioning, operator training, monitoring between vessels, and optimization of media change-out intervals against measured breakthrough.

Funding

  • Drinking Water State Revolving Fund: Low-interest loans and, for disadvantaged communities, principal forgiveness. Applications follow state cycles that must be planned around.

  • Federal emerging contaminant funding: Infrastructure legislation directed dedicated funding to emerging contaminants including PFAS, with a significant share reserved for small and disadvantaged communities.

  • Settlement funds: Litigation against PFAS manufacturers has produced settlements available to affected water systems, with claim deadlines and participation requirements that need attention early.

  • Cost recovery: Where a discrete responsible party can be identified, recovery may be possible — another reason to invest in source characterization.

  • Rates: Most utilities will fund part of the program through rates. Phasing increases and explaining them clearly is central to public acceptance.

Community Communication

PFAS is a subject where public concern often outpaces the technical picture. Utilities that publish monitoring results plainly, explain what the limits mean, set out the plan and its timeline, and are candid about rate impacts encounter far less opposition than those that communicate only when required. Rate increases for PFAS treatment are more readily accepted when the reason is understood.

Success Metrics

  • Compliance: finished water consistently below applicable limits.

  • Schedule: milestones met against the compliance deadline.

  • Operating cost: actual media life against the pilot-based forecast, which is the best early indicator of whether long-term budgets hold.

  • Residuals: a documented, currently available disposal route.

Conclusion

A PFAS Capital Improvement Plan turns a regulatory deadline into a sequenced, funded program. The elements that most determine success are early characterization including short-chain compounds, honest evaluation of alternatives to treatment, pilot testing before sizing, and realistic accounting for media replacement and residuals disposal over the asset’s life.

Given that design through construction typically runs three to five years, the schedule is the binding constraint for most utilities. Planning that assumes the PFOA and PFOS limits will stand, and treats any compliance extension as contingency rather than schedule, is the more defensible position. Longer-horizon considerations are explored in our coverage of long term PFAS solutions, and the particular constraints facing smaller systems in our discussion of rural water PFAS solutions.