Small Water Systems Pay the Most to Treat PFAS
A study published October 1, 2026 in Nature Communications found that the size of a water utility is the biggest single factor in what it costs to treat PFAS. Researchers at Georgia Southern University and the University of Nebraska–Lincoln compared the two most common treatment methods across U.S. water systems and concluded that small and rural systems carry a disproportionate share of the burden.
PFAS (per- and polyfluoroalkyl substances) are man-made chemicals that break down so slowly people call them "forever chemicals." The U.S. Environmental Protection Agency (EPA) limits two of the most common, PFOA and PFOS, to 4 parts per trillion in public drinking water. Small systems are most of the map: according to the EPA, more than 97% of the nation's roughly 156,000 public water systems serve 10,000 people or fewer. A lot of plants, warehouses, and offices sit in towns served by one of them.
97%+
Share of U.S. public water systems that serve 10,000 people or fewer
82
U.S. water systems the study modeled where PFOA or PFOS exceeded EPA's limit
5x+
Cost of treating one short-chain PFAS with ion exchange vs. PFOA, at the largest utility size
What Drives the Cost Up
The study weighed granular activated carbon, a bed of carbon that PFAS stick to as water passes through, against ion exchange resin, tiny beads that swap harmless ions for PFAS and hold onto them. Western Water's coverage of the paper reports the researchers modeled systems from about 30,000 gallons a day up to about 75 million. Four factors moved the numbers most:
System size
The researchers called utility size the "overarching driver." A small system spreads the cost of equipment and upkeep over far less water, so each gallon costs more to treat.
The type of PFAS
Short-chain PFAS, the smaller molecules, cost far more to treat. One short-chain compound cost more than five times as much as PFOA with ion exchange.
Source water
Natural organic matter in river and lake water competes with PFAS for space on activated carbon, which raises its cost. Groundwater and surface water behave differently.
Treatment choice
Ion exchange had a lower climate impact in the study. Activated carbon also catches organic matter and other trace contaminants.
According to Western Water's coverage, PFAS levels alone weren't the deciding factor. A very small system with modest PFAS levels could face higher costs per gallon than a larger system with much higher levels.
Neither Method Destroys PFAS
Activated carbon and ion exchange capture PFAS. They don't break them down. The study assumed the used carbon and resin would go to a landfill, and Western Water notes that hauling distance mattered most for the smallest ion exchange systems. In that model, the PFAS move out of the water and into a landfill, where they can stay for a very long time.
The same problem applies inside a building. Point-of-use systems that reduce PFAS at the tap collect them in their filters, and used filters from most systems go to a landfill too. Bottleless Nation sends the filters its team pulls during preventative maintenance to Reworld for thermal destruction at 1,100°C. According to Reworld, an EPA-validated study at its Lake County, Florida facility in spring 2024 found 99% destruction of the PFAS surrogate compound (a stand-in chemical) the study tracked. Bottleless Nation reduces PFAS in the water, and Reworld destroys what the filters capture.
| Approach | Where it works | Where the PFAS end up |
|---|---|---|
| Granular activated carbon | At the utility's treatment plant | Landfill, in the study's model |
| Ion exchange resin | At the utility's treatment plant | Landfill, in the study's model |
| Bottleless Nation reverse osmosis | At the tap inside your building | Thermal destruction at Reworld |
The Nature Communications study didn't model reverse osmosis. EPA's research team describes reverse osmosis membranes as highly effective against PFAS, shorter-chain types included, and as well suited to point-of-use treatment, where the volume of water is small.
What the Study Means for a Plant or Office in a Small Town
Public water systems that exceed EPA's PFOA and PFOS limits have until 2029 to fix it. In May 2026, EPA proposed letting systems ask for two more years, to 2031. That proposal isn't final, and EPA's broader proposed PFAS changes could shift the timeline again. For a small utility facing the highest cost per gallon, the study's findings point to a harder climb to meet those limits.
A business on a small system can still find out where its water stands:
- Read the annual water quality report. Every community water system publishes one. Search it for PFOA, PFOS, and "PFAS."
- Check your zip code. Bottleless Nation's free tap water lookup shows contaminants detected in your local supply.
- Ask the utility about its plan. Ask whether it has sampled for PFAS, what it found, and whether treatment is funded.
The PFAS guide for businesses covers health effects, testing, and the federal rules in full.
Purified Water at the Tap, Wherever the Building Is
Bottleless Nation's S1, S3, and M6 purify water at the unit with four or five stages built around reverse osmosis, which pushes water through a membrane so fine most contaminants can't get through. An in-tank UV LED light keeps stored water sanitized, and the units are certified to NSF/ANSI 58 for reverse osmosis and NSF/ANSI 55 for UV. They reduce PFAS along with many of the other contaminants found in tap water.
Each unit connects to the building's water line, so there are no jugs to order or store. Installation is included at no extra charge, and so are service calls. Bottleless Nation's team handles the annual preventative maintenance and the annual filter change, and tests the total dissolved solids (TDS) of your tap water and the purified water with a meter at every visit. Small towns are part of the map: Bottleless Nation has set up water and ice for a poultry producer in Milford, Indiana and bulk ice for a waste and recycling site in Prairie du Sac, Wisconsin.
Phenomenal service! Ben K came to look at our unit and got everything resolved extremely quick. Then took the time to fully explain everything and answer questions. Wish all customer service was that smooth.
— Joel E., Altoona, WI (Google review)
Bottleless Nation serves businesses in 33 markets nationwide and the towns around them, and can build a setup for nearly any kind of building.
Talk to Bottleless Nation about purified water for your building.
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Frequently Asked Questions
What counts as a small water system?
EPA counts a public water system as small when it serves 10,000 people or fewer. More than 97% of U.S. public water systems fall in that group.
Does this study mean my water has PFAS?
No. The study modeled treatment costs; it didn't test local water. Your utility's annual water quality report and a zip code lookup show what's been detected in your supply.
Does reverse osmosis reduce short-chain PFAS?
EPA's research team describes reverse osmosis membranes as highly effective against a wide range of PFAS, shorter-chain types included. Ask any vendor which contaminants its certification covers.
What happens to Bottleless Nation's used filters?
Bottleless Nation's team pulls them during the annual filter change and sends them to Reworld for thermal destruction at 1,100°C instead of a landfill.
Is installation included?
Yes. Installation is included at no extra charge, and so are service calls. The unit connects to the building's existing water line.
Does Bottleless Nation work with businesses in small towns?
Yes. Bottleless Nation serves 33 markets and the communities around them, from small manufacturing towns to metro areas. The all-locations page lists every market.