Dayton residents asking questions about their tap water right now have reason to. The city filed a lawsuit in February 2026 seeking more than $300 million from Wright-Patterson Air Force Base, alleging that PFAS contamination migrating from the base has pushed one of the city's two treatment plants to PFAS levels 3–4 times above incoming federal limits — and that fixing it will cost nearly $400 million.
Here's what residents actually need to know.
What's Happening with Dayton's Water
Dayton draws drinking water from two well fields: the Mad River Well Field and the Ottawa Well Field. The Ottawa plant is the problem.
PFAS contamination has been migrating from Wright-Patterson Air Force Base — which historically used PFAS-containing firefighting foam (AFFF) for decades of training exercises — into the groundwater feeding Dayton's Ottawa wells. City monitoring wells upstream of the Ottawa production wells are showing PFAS concentrations that Dayton's legal filings describe as potentially hundreds of times above the new federal limits.
The Ottawa treatment plant has been running at PFAS levels consistently 3–4 times above EPA's new 4 ppt limit for PFOA and PFOS. Dayton has already spent $14 million on emergency response, including a blending system to mix water between the two plants to dilute detected levels. Installing a proper treatment system at the Ottawa plant is estimated to cost $384 million to build and $70 million to operate over 20 years — hence the lawsuit.
The key number to understand: The EPA's new MCL for PFOA and PFOS is 4 parts per trillion. Dayton's Ottawa plant has been consistently above that. However, compliance with the new MCL is not legally required until 2029 (recently extended from the original 2029 deadline, with further extension to 2031 under discussion). The city is not currently in violation of any enforceable standard — but residents who want to act on the best available science rather than wait for compliance deadlines have legitimate reason to do so.
Is Dayton Tap Water Safe to Drink?
This is the question everyone wants a direct answer to, and it deserves one.
For healthy adults: Dayton tap water currently meets all legally enforceable federal and Ohio EPA drinking water standards. The city is not under a boil order or any formal advisory to avoid tap water. The PFAS MCL of 4 ppt won't be legally enforceable until 2029 at the earliest — currently the water that reaches your tap is being actively blended to reduce overall PFAS exposure.
For pregnant women, infants, and young children: PFAS health effects are not linear — the developing fetus, nursing infants, and young children face higher risks from the same exposure level as a healthy adult. If you're pregnant or have an infant, reducing PFAS exposure to as low as reasonably achievable is a reasonable precaution while the city works toward full treatment capacity.
The honest framing: Regulatory compliance is not the same as zero risk. Dayton's situation is one of uncertain exposure at levels above what the EPA has determined represents a meaningful health threshold — not a crisis requiring immediate action, but not something to dismiss either.
What Dayton Is Doing About It
The city has been more proactive than most utilities on PFAS:
- Since 2017: Active monitoring of PFAS levels, one of the first utilities in Ohio to implement systematic tracking.
- 2023: Hired major consulting firm to design advanced treatment; partnered with EPA Office of Research and Development on pilot project.
- 2024: Launched blending system to manage distribution-level PFAS concentrations; secured Ohio EPA funding for remediation projects.
- February 2026: Filed lawsuit in federal court against Wright-Patterson Air Force Base seeking over $300 million in remediation costs.
The city operates over 500 monitoring wells and publishes current PFAS levels for both treatment plants on its website at daytonohio.gov. That level of transparency is not universal among utilities.
What Residents Can Do Right Now
The city's official guidance says tap water is safe and does not recommend switching to bottled water. That guidance is consistent with EPA's own position on comparable situations. But if you want to reduce your household's PFAS exposure while the larger remediation plays out over years, here are your practical options.
Best Option: Certified Point-of-Use Filter
The most cost-effective approach for most Dayton households is a point-of-use filter at the kitchen tap — specifically one certified for PFAS removal. Not all filters remove PFAS. You need one certified to NSF/ANSI 58 (reverse osmosis) or NSF/ANSI 53 for PFAS specifically.
Reverse osmosis (highest reduction, 94–99%):
- Bluevua RO100ROPOT-LITE Countertop RO (~$299) — no installation, plug-in countertop unit, NSF 58 certified, excellent choice for renters or anyone who doesn't want plumbing work
- APEC ROES-50 Under-Sink RO (~$215) — requires one faucet hole, NSF 58 certified, best value for homeowners
- Waterdrop G3P600 Under-Sink RO (~$400) — tankless, more compact, fast flow
Activated carbon (lower cost, less complete):
- Clearly Filtered Pitcher (~$90) — independently certified to remove PFAS, lead, and 360+ contaminants; the most capable pitcher filter available
What doesn't help: standard Brita pitcher filters, generic refrigerator filters, and most faucet-mount filters are not certified for PFAS removal. The Brita Standard filter (white) and most basic carbon filters do not meaningfully reduce PFAS.
For full detail on how PFAS filtration works and which certifications to look for, see our PFAS in drinking water guide.
What About Bottled Water?
The city and EPA do not recommend bottled water as the solution here — and not just because of cost and plastic waste. Studies have found PFAS in some bottled water brands as well. A certified home filter is more reliable, cheaper per gallon, and produces no plastic waste.
Check Your Specific Address
Dayton's contamination is concentrated in the Ottawa Well Field service area. Depending on where in Dayton you live, your water may come primarily from the Mad River system (lower PFAS) or the Ottawa system (higher PFAS), or a blend of both.
→ Enter your ZIP at PureCity to see the specific water quality data for your address and ZIP code — including reported contaminant levels and how they compare to federal limits.
The Bigger Picture: Ohio and PFAS
Dayton is not alone. Ohio EPA testing has found detectable PFAS in over 100 public water systems statewide. The EWG's March 2026 update using the latest UCMR5 federal data identifies 176 million Americans served by water with detected PFAS. The Dayton situation — PFAS from military base firefighting foam migrating into a city well field — is one of the most common contamination patterns in the country, repeated at hundreds of sites near Air Force bases, military installations, and airports.
The compliance deadlines are being pushed out. The liability fight between cities and the Department of Defense will take years. The treatment infrastructure will take years more to build. That's the honest situation, and it's why individual household filtration — a $200–$400 one-time investment — is a reasonable bridge for families who don't want to wait.
Related Articles
- PFAS in Drinking Water: What It Is, Where It's Found, and How to Filter It
- Best Water Filter for Renters: No Drilling, No Landlord Drama
Sources: City of Dayton Water Department · WYSO/WOSU: Dayton Sues Wright-Patt, March 2026 · EPA PFAS Drinking Water Standards · EWG PFAS Contamination Map, updated March 2026 · Montgomery County Public Health: PFAS Resources