Independent Hamilton water guide: This website is an independent informational resource and is not operated by, affiliated with, or endorsed by the City of Hamilton, Ohio EPA, U.S. EPA or another government agency.
A Consumer Confidence Report is an annual summary, not a live boil-water or outage alert. For an active water-quality emergency, follow the newest City of Hamilton notice or contact Water Production directly.
Hamilton Drinking Water Quality: 2026 Guide to the Latest Annual Report
Hamilton, Ohio • Public Water System OH0904012
What Hamilton’s Latest Water Quality Report Actually Says
The Hamilton Public Water System gets 100% of its drinking water from the Great Miami Buried Valley Aquifer. The City’s latest linked Consumer Confidence Report says Hamilton’s drinking water met or exceeded federal and state requirements for the reporting period and that the water system held a current, unconditioned license to operate.
The report also provides real numbers for lead, copper, nitrate, fluoride, disinfectants and PFAS monitoring—plus an explanation of Hamilton’s North and South Water Treatment Plants and the steps used to soften, filter and disinfect groundwater.
Answer first
Did Hamilton’s Latest Water Report Show a Drinking-Water Violation?
The report says Hamilton drinking water met or exceeded federal and state requirements.
The City also states that the Hamilton Public Water System had a current, unconditioned license to operate when the report was prepared.
Water can meet systemwide standards while an individual home’s plumbing contributes lead, sediment, odor or another localized issue. The City’s report specifically notes that plumbing and service-line materials can affect lead exposure at a property.
Avoid a common date mistake
Why the “2026” Hamilton Water Report Search Leads to 2024 Data
This page was reviewed in August 2026.
The official PDF is titled “2025 City of Hamilton Water Quality Report.”
The document summarizes testing performed during calendar year 2024.
If you are discussing contaminant results such as lead, copper, fluoride, nitrate or PFAS from this report, identify them as 2024 sampling results reported in Hamilton’s 2025 CCR. Do not describe them as tests performed in 2026.
The City’s Utility Bill Inserts page links customers to the current Water Quality Report.
100% groundwater supply
Where Does Hamilton, Ohio Drinking Water Come From?
Hamilton meets 100% of customer drinking-water demand with groundwater.
The aquifer consists largely of sand and gravel deposited by glaciers. Hamilton’s report says raw groundwater is pumped from roughly 210 feet below the surface.
The City’s current utility information describes 21 deep wells: 16 production wells associated with the South Water Treatment Plant and five at the North Water Treatment Plant.
Hamilton water system snapshot
North & South Water Treatment Plant Capacity
40 MGD lime-softening plant
The City’s Utility Operations page says the South Plant draws water through 16 high-capacity production wells located throughout the City of Fairfield.
6 MGD lime-softening plant
The North Plant uses five onsite production wells. The City states individual production wells can produce approximately 3–4 million gallons per day.
From aquifer to faucet
How Hamilton Treats Drinking Water
Hamilton uses lime softening to reduce water hardness and remove precipitated solids before filtration.
Carbon dioxide is added during recarbonation to stabilize the softened water and adjust pH.
Hamilton uses chlorine dioxide as a disinfectant to control microorganisms.
Numbers residents search for
Hamilton Water Test Results: Key Regulated Substances
| Substance | Standard | South Plant | North Plant | Violation? |
|---|---|---|---|---|
| Chlorine dioxide ppb |
MRDL 800 | 510 210–510 |
590 220–590 |
No |
| Chlorite ppm |
MCL 1 | 0.63 0.06–0.82 |
0.55 0.35–0.60 |
No |
| Fluoride ppm |
MCL 4 | 0.87 0.70–1.11 |
0.71 0.64–0.91 |
No |
| Nitrate ppm |
MCL 10 | 0.58 | Not detected | No |
| Barium ppm, sampled 2023 |
MCL 2 | 0.0527 | 0.0335 | No |
| cis-1,2-Dichloroethylene ppb |
MCL 70 | Not listed as detected | 0.09 | No |
Ohio EPA may allow certain stable contaminants to be monitored less frequently than annually. The report therefore includes the most recent qualifying result and states the year sampled rather than pretending every substance was tested in 2024.
Lead & Copper Rule
Hamilton Lead and Copper Results
The City notes that lead in drinking water can come from service lines, fittings, fixtures and household plumbing. Homes with older plumbing materials may have different exposure than the systemwide sampling result suggests.
Who owns the water service line?
The City’s lead-awareness information explains that Hamilton maintains the public portion up to and including the curb valve when applicable.
The section from the curb valve to the building or residence is owned and maintained by the property owner under City Ordinance 939.09.
If you are concerned about lead at your home
-
1
Check your service-line material
Use Hamilton’s Lead Awareness page and linked service-line inventory map.
-
2
Use cold water for drinking and cooking
Water that has been sitting in plumbing can pick up more lead from plumbing materials.
-
3
Flush stagnant plumbing
The CCR advises flushing pipes for several minutes after prolonged non-use by running water or completing other household water use.
-
4
Consider a certified filter if needed
The City recommends using a filter certified by an ANSI-accredited certifier for lead reduction when appropriate.
-
5
Ask about testing
Call City of Hamilton Water Production at 513-785-7430 for current water-testing and lead information.
UCMR5 monitoring
PFAS in Hamilton Water: What the Latest Report Shows
The report lists several PFAS detections at the South Plant and non-detects at the North Plant.
These values appeared in the report’s unregulated-substances/UCMR5 section. They should not be read as a simple pass/fail table.
No such violation is identified in Hamilton’s report. The table presented these results under UCMR5/unregulated monitoring. Federal PFAS implementation is also time-dependent: compliance determinations rely on required monitoring and running annual averages, not one historical screening result.
As of this August 2026 review, U.S. EPA says the 4.0-ppt federal MCLs for PFOA and PFOS remain in place. EPA proposed in May 2026 to create an option for qualifying systems to receive additional compliance time through 2031. EPA is separately reconsidering regulations for several other PFAS. Therefore, use current EPA and Ohio EPA information when evaluating future compliance—not only Hamilton’s historical UCMR5 table.
The report states that its tables display substances that were detected. Do not interpret the absence of a PFOS row as permission to invent a numeric result.
Aquifer vulnerability
Why Hamilton’s Source Water Is Rated Highly Susceptible to Contamination
“High susceptibility” describes vulnerability of the aquifer—not a finding that tap water is unsafe.
The Ohio EPA source-water assessment identified three primary reasons for the high susceptibility rating:
The aquifer lacks a thick clay barrier that would otherwise slow movement of contaminants from the surface.
The water-bearing sand-and-gravel formation is accessible enough that source protection remains important.
The protection area contains activities and sites that could affect groundwater if contaminants were released.
Hamilton to New Baltimore Groundwater Consortium
Hamilton participates in a regional groundwater-protection program that uses education, source-control strategies, groundwater monitoring and emergency-response planning to protect the Great Miami Buried Valley Aquifer.
The City’s current directory lists Source Water Protection at 513-383-3162.
2026 hydrant flushing
Why Hamilton Water Can Temporarily Look Discolored During Flushing
The City performs water-main flushing to move water rapidly through distribution pipes, remove accumulated sediment and maintain water quality. Hamilton’s report specifically mentions iron and manganese sediment as substances that can affect water’s color, clarity and taste even though they are not necessarily health concerns at the conditions being discussed.
If active flushing is occurring on your street, wait until the work is complete when practical.
The CCR advises running cold water at full velocity for several minutes until it clears.
Using hot water while sediment is moving can pull material into the water heater.
Persistent color, odor, taste or particles should be reported rather than assumed to be flushing.
Tap-water problem today
What to Do if Hamilton Water Looks, Smells or Tastes Unusual
Check whether it clears
Fill a clear glass and observe whether cloudiness clears from bottom to top, which may indicate dissolved air.
Check flushing activity
Sediment can be temporarily disturbed by hydrant flushing, main work or a water-main break.
Use cold water & report persistence
Flush stagnant plumbing and contact Water Production if the condition continues.
Check nearby properties
If neighbors are affected too, a distribution-system issue or planned work may be involved.
Check service-line material
Review the City’s lead inventory and ask Water Production about testing.
Follow the newest notice
A live boil advisory overrides general annual-report guidance. Follow the City’s exact instructions until the advisory is lifted.
The CCR summarizes historical compliance. For a current incident, check Hamilton Utility Safety, City notices and MyHamilton 311 or contact the utility.
Phones & customer office
Hamilton Water Department Contact Information
Current City directory number for drinking-water production questions.
The latest CCR lists Jay Mosley, Water Production Superintendent, for questions about the report.
Current City directory number for distribution-system routing.
Current source-water protection contact in the City directory.
Utility bills, account questions and customer service.
City lead-awareness page directs residents here for additional health information.
345 High Street
City of Hamilton
345 High Street
Hamilton, OH 45011
The City says utility customer service is located in the portion of the building nearest the corner of MLK Boulevard and High Street.
Customer Service: 513-785-7100
Email: customerserviceweb@hamilton-oh.gov
Hours: Monday–Friday, 8:30 a.m.–5:00 p.m. Eastern
Public participation
Where Hamilton Residents Can Raise Utility Questions Publicly
Council Chambers, 345 High Street.
Hamilton Municipal Garage, 2210 S. Erie Boulevard.
Verify the current agenda/calendar before attending. A scheduled meeting is not the appropriate route for an urgent water-quality or service problem.
CCR decoder
How to Read Hamilton’s Water Quality Table
Examples include nitrate, fluoride, lead, copper, chlorite and PFOA.
Some contaminants may have a result from an earlier year because monitoring frequency differs.
The relevant regulatory benchmark depends on the substance.
Look at both the reported amount and the low-to-high range when provided.
A detected contaminant does not automatically mean a regulatory violation occurred.
This helps explain whether a substance is naturally occurring, treatment-related or associated with human activity.
Report terminology
Hamilton Water Quality Report Definitions
- CCR
- Consumer Confidence Report—the annual drinking-water quality report provided to customers.
- MCL
- Maximum Contaminant Level—the highest level of a contaminant allowed in drinking water under the applicable regulation.
- MCLG
- Maximum Contaminant Level Goal—a non-enforceable health goal below which there is no known or expected health risk.
- AL
- Action Level—a concentration that triggers treatment or other requirements for contaminants such as lead and copper.
- MRDL
- Maximum Residual Disinfectant Level—the highest level of a disinfectant allowed in drinking water.
- 90th Percentile
- The lead/copper result that is equal to or greater than 90% of the sampled site results.
- ND
- Not detected by the laboratory at the applicable analytical reporting level.
- ppm
- Parts per million, equivalent to milligrams per liter for water.
- ppb
- Parts per billion, equivalent to micrograms per liter for water.
- ppt
- Parts per trillion, equivalent to nanograms per liter for water.
- UCMR5
- EPA’s Fifth Unregulated Contaminant Monitoring Rule, used to collect occurrence data for contaminants not historically regulated under routine drinking-water rules.
- Aquifer
- An underground geologic formation capable of storing and transmitting groundwater.
Primary official references
Official Hamilton Water Quality Resources
Latest City-Linked CCR
Hamilton’s 2025 Water Quality Report, covering reporting year 2024.
Open ReportUtility Bill Inserts
City page currently linking the water-quality report and 2026 hydrant-flushing resource.
City ResourcesUtility Operations
North and South treatment capacities, well counts and treatment process.
Utility OperationsUtilities About
Current system description, customer counts and water-main mileage.
Water System OverviewLead Awareness
Service-line ownership, inventory and lead-reduction information.
Lead AwarenessCity Directory
Current Water Production, Source Water Protection, Distribution and billing numbers.
City DirectoryUtility Safety
Boil advisories, broken water lines, shutoff-valve safety and other current utility guidance.
Utility SafetyU.S. EPA PFAS Rules
Current federal drinking-water PFAS standards and 2026 rulemaking information.
EPA PFASReviewed: August 22, 2026. The water-quality values above are tied to the sampling years shown in Hamilton’s latest available City-linked report. Current alerts, PFAS regulations, personnel and contact details can change after this review.
People also ask
Hamilton Water Department Water Quality FAQs
Is Hamilton, Ohio tap water safe according to the latest water quality report?
Hamilton’s latest City-linked Consumer Confidence Report states that its drinking water met or exceeded federal and state requirements and that the public water system had a current, unconditioned license to operate. The report summarizes systemwide compliance and does not guarantee that every individual home’s plumbing is free of localized issues.
Is there a 2026 Hamilton Water Quality Report?
During the August 22, 2026 review for this guide, the report linked by the City was titled the 2025 City of Hamilton Water Quality Report. Its cover identifies reporting year 2024, and the report describes testing performed from January 1 through December 31, 2024. This page is therefore a 2026 guide to the latest City-linked report, not a claim that the tests were performed in 2026.
Where does Hamilton, Ohio get its drinking water?
Hamilton gets 100% of its drinking water from the Great Miami Buried Valley Aquifer. Groundwater is pumped through 21 deep production wells and treated at the City’s North and South Water Treatment Plants.
What was the lead level in Hamilton water?
For 2024 lead sampling, the latest report gives a 90th-percentile lead result of 2 parts per billion, with a range from not detected to 3.4 ppb. Zero of 33 sample sites exceeded the 15-ppb lead action level.
What was the copper level in Hamilton water?
The 2024 copper sampling result was 0.032 ppm at the 90th percentile, with a range of 0.002 to 0.112 ppm. Zero of 33 sampled sites exceeded the 1.3-ppm copper action level.
Did Hamilton detect PFAS in drinking water?
Yes. Hamilton’s UCMR5/unregulated-substances table lists South Plant detections including PFBS at 3.6 ppt, PFHxS at 4.4 ppt and PFOA at 5.3 ppt, with those substances reported as not detected at the North Plant. The report did not identify these UCMR5 results as a drinking-water violation.
Does Hamilton’s 5.3-ppt PFOA result mean the water system violated the federal PFAS rule?
No violation is identified in Hamilton’s report from that UCMR5 result. Federal PFAS compliance involves required monitoring and running annual averages rather than treating one historical UCMR result as a final compliance determination. As of August 2026, EPA says the PFOA and PFOS MCLs remain 4.0 ppt each while a 2026 proposal addresses possible additional compliance time for qualifying systems.
Why can Hamilton water look brown or discolored during hydrant flushing?
Water-main flushing can temporarily disturb iron, manganese and other sediment that has accumulated in distribution pipes. Hamilton advises residents affected by flushing to run cold water for several minutes until it clears and to avoid pulling sediment into the hot-water tank.
Who do I call about Hamilton drinking-water quality?
The City’s current directory lists Water Production at 513-785-7430. The latest Consumer Confidence Report separately lists Water Production Superintendent Jay Mosley at 513-785-7429 for questions concerning that report.
How can I find out whether my Hamilton home has a lead service line?
Use the City of Hamilton Lead Awareness webpage and its linked service-line inventory map. Hamilton explains that the property owner generally owns and maintains the portion from the curb valve to the building, while the City is responsible for the public portion through the curb-valve area. For current testing or lead questions, contact Water Production at 513-785-7430.