Water system
Oxford City
EPA ID OH0902312 · Butler County · 24,000 people served · owned by a local government
Oxford City treats its own water from Great Miami Buried Valley Aquifer (wells).
The system's record
- Aquifer
- Great Miami Buried Valley Aquifer
- Active wells
- 7
- Serves
- 24,000 people · Butler County
- EPA ID
- OH0902312
About this area's water
Did you know
- Oxford's tap water is genuinely hard - 340 to 380 ppm - and the city has never softened it; the plant now being built will bring roughly 60% of the supply down to about 120 ppm.
- The utility serves more than 22,500 customers, far more than the year-round population, because Miami University is on the system.
- Oxford's wells sit in a federally designated Sole Source Aquifer, but the same shallowness that makes the aquifer productive is why the city's own report calls all of its sources highly susceptible to contamination.
- The city is a claimant in the 3M PFAS class-action settlement, with payouts continuing through 2036, and has already been promised reimbursement of the roughly $6,000 it spent on PFAS testing.
- Oxford pays the full cost of replacing the homeowner's side of a lead service line - the program FAQ answers 'Will I need to reimburse the City? No!'
History5
- early 1990sThe current Oxford Water Treatment Plant was built - with no water softening capability.
- 2024PFAS confirmed in multiple samples at the Seven Mile well field in May 2024 testing, none above regulatory limits; no consistent positive samples at the Four Mile Valley well field.
- 2024City proposes the largest capital improvement plan in its history, $76.44 million for FY2025-2029, headlined by $18.9 million of water treatment plant improvements to soften the water and remove PFAS…
- 2026June 2, 2026: City Council approved a contract with Building Crafts Inc. to construct the new treatment facility - $23,632,340 construction plus $1,167,660 contingency ($24.8 million).
- 2026March 30, 2026: second round of federal PFAS compliance sampling completed; only PFBS and PFOA detected, both far below limits.
Treatment & pressure
How it is treated
All groundwater. Well fields north and east of the city (the Four Mile Valley and Seven Mile fields) draw from the Greater Miami Buried Valley Aquifer, a federally designated Sole Source Aquifer of glacial sand and gravel. The Water Treatment Plant, built in the early 1990s, chlorinates and…
Source: cityofoxford.orgcityofoxford.orgoxfreepress.com
Water pressure
Not published - no psi figure appears on the city's water treatment and distribution pages or in the 2025 Consumer Confidence Report.
Source: cityofoxford.orgcityofoxford.org
What it costs
Not published online, confirmed on two city pages: the Utilities page says the city provides water, sewer and refuse service and gives only a phone number (513-524-5221), and the…
Water quality & impurities10
| Contaminant | Level | Limit | Year |
|---|---|---|---|
| Nitrate Fertilizer runoff, septic/sewage leaching, natural deposits. | 1.45 ppm | 10 (MCL) | 2025 |
| Fluoride Range 0.87-1.01; added to promote strong teeth. | 1.01 ppm | 4 (MCL) | 2025 |
| Total trihalomethanes (TTHM) Range 9.4-15. | 15.0 ppb | 80 (MCL) | 2025 |
| Haloacetic acids (HAA5) Range 1.4-2.3. | 2.3 ppb | 60 (MCL) | 2025 |
| Chlorine Range 1.08-1.32. | 1.12 ppm | 4 (MRDL) | 2025 |
| Lead (90th percentile) None of 30 samples above the action level. | 2.4 ppb | 15 (action… | 2025 |
| Copper (90th percentile) None of 30 samples above the action level. | 0.18 ppm | 1.3 (action… | 2025 |
| PFBS (perfluorobutanesulfonic acid) Plant tap; range 1.26-8.2. Sampled 3/30/2026 under the 2024 federal PFAS rule. | 8.2 ppt | no federal MCL | 2026 |
| PFOA (perfluorooctanoic acid) Plant tap; range ND-0.21. The other four regulated PFAS (PFOS, HFPO-DA, PFHxS, PFNA) were non-detect. | 0.21 ppt | 4 (federal MCL) | 2026 |
| Hardness (not a regulated contaminant) Reported in local coverage of the softening project; the new membrane plant targets about 120 ppm. | 340-380 ppm | no standard… | 2026 |
Source: cityofoxford.orgoxfreepress.com
EPA compliance record
Lead at the tap: 90th-percentile result 2.4 ppb in 2025 (action level 15 ppb).
EPA record: no health-based violations since 2015.
Projects & plans5
Recent and current work
- New membrane-softening Water Treatment Facility · $25 million · 2026- · planned
Council approved the construction contract with Building Crafts Inc. on June 2, 2026: $23,632,340 construction plus $1,167,660 contingency. Adds membrane… - Lead Service Line Replacement Program · ongoing · under construction
Council-approved city funding pays for the property owner's portion of lead, galvanized or unknown-material service lines at no cost and with no reimbursement…
Source: oxfreepress.comcityofoxford.org
Planned or needed
- Biotower media replacement (wastewater treatment plant) · $5.7 million · FY2025 · planned
Listed in the FY2025-2029 capital improvement plan. - Water well revamping · FY2025 · planned
In the capital improvement plan; may include installing an additional well. No cost published. - Solar installations at the water treatment plant, Seven Mile Well Field and wastewater plant · unknown · proposed
Under discussion; the water treatment plant site showed the highest lifetime savings, just over $580,000. No capital cost published.
Source: oxfreepress.com
Supply stress
The Greater Miami Buried Valley Aquifer is a federally designated Sole Source Aquifer and a high-yield source, but Oxford's own 2025 CCR states that all of its water sources 'have been determined to have a high susceptibility to contamination, largely due to the shallow depth of the aquifer and the lack…
Sewers
Sanitary
The city operates its own Wastewater Treatment Plant at 501 McKee Ave., treating about 2.25 million gallons per day collected through more than 65 miles of sewer pipe and discharging to Four Mile Creek under an NPDES permit. Design capacity is not published. The capital plan includes a $5.7 million biotower media replacement. No combined…
Storm
The city groups stormwater with its water and wastewater services but publishes no stormwater fee, program detail or flooding assessment in the pages reviewed.
Source: cityofoxford.orgoxfreepress.com
Sourcesverified
Compiled from the utility's own reports and public records, then independently re-checked against primary sources.
Main supplier in 1 ZIP code
Serves
Main water supplier in 1 ZIP code
- 45056 · Oxford77% of residents
Population-weighted resident shares; a ZIP code can have more than one system on record. Recomputed from each ZIP's own system list, not from the map's cached footprint.
Buys from · Sells to
Oxford City does not buy water from another system on record; it treats its own source water.
No other system is on record buying water from Oxford City.
What the records show about Oxford City
Who runs it
EPA's record describes Oxford City as owned by a local government. It has 4,982 service connections and serves 24,000 people.
EPA classes it as a community water system, one that serves the same residents all year.
Its office telephone on EPA's record is 513-523-1753.
Source: EPA Safe Drinking Water Information System (SDWIS), water system record.
How the water is treated
EPA's treatment table registers these steps for Oxford City: aeration, chlorine disinfection, fluoridation, and sand or media filtration.
The list is what each system registered with EPA for treatment plants EPA still shows as active, and it can lag a plant upgrade.
Source: EPA Safe Drinking Water Information System (SDWIS) treatment table (EPA Envirofacts, pulled September 2026).
Violations
EPA's record shows no health-based violations for Oxford City since 2015.
EPA logs no violations of any kind for Oxford City since 2020.
Source: EPA Safe Drinking Water Information System (SDWIS) violation records: health-based violations with compliance periods beginning in 2015 or later, all violations from 2020 or later (EPA Envirofacts, pulled September 2026).
Lead and copper at the tap
In the sampling period ending December 2025, the 90th-percentile lead result at Oxford City was 2.4 ppb, under both the current 15 ppb action level and the 10 ppb level that applies from 2027.
The highest result on file is 12 ppb, in the period ending December 2016.
EPA has 9 sampling periods on file for Oxford City since 2016, the first ending in 2016; 1 of the 9 periods went above 10 ppb.
Every water system has to inventory its service lines, the pipes from the main to each building. In the inventory Oxford City sent EPA, 4,848 lines are counted.
| Material | Lines |
|---|---|
| Lead | 4 |
| Galvanized, needing replacement | 66 |
| Unknown material | 2 |
| Not lead | 4,776 |
| All lines | 4,848 |
Systems sample taps in the homes most likely to have lead pipes or solder. The 90th-percentile result is the level nine in ten of the sampled homes were at or below. Lead comes mostly from service lines and house plumbing, not the source water, so a low result for the system does not clear an old house.
EPA's dashboard status for this inventory: reported all required service line types.
Source: EPA Safe Drinking Water Information System (SDWIS) lead and copper 90th-percentile results (EPA Envirofacts), sampling periods ending 2016 or later; EPA's service line inventory dashboard, Ohio's 2026 Q2 submission.
PFAS
EPA's fifth national round of testing (UCMR 5) took 2 samples of the water entering the pipes of Oxford City in 2024 and measured 29 PFAS.
PFOA and PFOS were not detected, against a federal limit of 4 ng/L each.
The highest PFAS result was PFBS 12.6 ng/L.
Ohio EPA's own statewide sampling tested 1 plant of Oxford City (latest sample May 2021). Not one of the six PFAS tested (PFOA, PFOS, PFHxS, PFNA, GenX and PFBS) was detected.
Ohio EPA's current sampling status map lists 1 plant of Oxford City as sampled, most recently August 2026.
| Compound | Highest result | Federal limit |
|---|---|---|
| PFOA | not detected | 4 ng/L |
| PFOS | not detected | 4 ng/L |
PFAS are the 'forever chemicals' from firefighting foam, plating shops and non-stick coatings. Results are for water leaving the plant, not your tap.
Source: EPA UCMR 5 occurrence data (final release, August 2026); Ohio EPA statewide PFAS sampling, 2019 to 2021, and its sampling status map.
Disinfection byproducts
Chlorine that disinfects water also reacts with organic matter to form byproducts. Two groups have federal limits: total trihalomethanes (TTHM, 80 µg/L) and five haloacetic acids (HAA5, 60 µg/L), judged on running yearly averages at each sampling site.
For TTHM, the average of Oxford City's samples in 2019, the last year it was sampled, was 12.9 µg/L. The worst yearly average was 32.5 µg/L and the highest single sample was 32.5 µg/L, from 37 samples taken from 2012 to 2019.
For HAA5, the average in the last year sampled was 2.5 µg/L. The worst yearly average was 6.2 µg/L and the highest single sample was 9.4 µg/L, from 37 samples.
| Byproduct | Limit | Latest yearly average | Worst yearly average | Highest sample | Samples |
|---|---|---|---|---|---|
| TTHM | 80 µg/L | 12.9 µg/L (2019) | 32.5 µg/L | 32.5 µg/L | 37 |
| HAA5 | 60 µg/L | 2.5 µg/L | 6.2 µg/L | 9.4 µg/L | 37 |
A yearly average of 0 means nothing was detected in that year's samples. EPA's file stops at 2019; Ohio EPA's Drinking Water Watch has newer results.
Source: EPA Six-Year Review 4 compliance monitoring data, 2012 to 2019, distribution-system samples (non-detects counted as zero).
Nitrate, arsenic and radioactivity
Nitrate: the highest of 8 samples was 2.8 mg/L (as nitrogen), in 2019, the last year sampled. No sample was over the limit of 10 mg/L. Nitrate above 10 is unsafe for infants.
Arsenic was not detected in 2 samples (limit 10 µg/L).
| Contaminant | Samples | Highest result | Limit | Samples over limit |
|---|---|---|---|---|
| Nitrate (as nitrogen) | 8 | 2.8 mg/L | 10 mg/L | 0 |
| Arsenic | 2 | not detected | 10 µg/L | 0 |
Measured in finished water: at the plant's entry points and in the distribution system; raw well and intake samples are left out. Non-detects count as zero.
Source: EPA Six-Year Review 4 compliance monitoring data, 2012 to 2019, finished water.
Solvents and fuels
EPA's file holds results for all six solvent and fuel compounds it checked. Benzene, carbon tetrachloride, 1,2-dichloroethane, trichloroethylene, tetrachloroethylene, and vinyl chloride were not detected in 2 samples each.
| Compound | Limit | Samples | Detected in | Highest result | Samples over limit |
|---|---|---|---|---|---|
| Benzene | 5 µg/L | 2 | 0 of 2 | not detected | 0 |
| Carbon tetrachloride | 5 µg/L | 2 | 0 of 2 | not detected | 0 |
| 1,2-dichloroethane | 5 µg/L | 2 | 0 of 2 | not detected | 0 |
| Trichloroethylene (TCE) | 5 µg/L | 2 | 0 of 2 | not detected | 0 |
| Tetrachloroethylene (PCE) | 5 µg/L | 2 | 0 of 2 | not detected | 0 |
| Vinyl chloride | 2 µg/L | 2 | 0 of 2 | not detected | 0 |
"Not detected" means the lab's result was below what its method can measure, not that the compound is absent. Non-detects count as zero in the highest-result column.
Source: EPA Six-Year Review 4 compliance monitoring data, 2012 to 2019, finished water.
Farm chemicals and metals
EPA's file holds results for 8 of the nine herbicides and metals it checked. Detected: barium in 2 of 2 samples, highest 102 µg/L (limit 2,000). Not detected: atrazine, alachlor, chromium, cadmium, mercury, selenium, and thallium, in 2 samples each.
| Substance | Kind | Limit | Samples | Detected in | Highest result | Samples over limit |
|---|---|---|---|---|---|---|
| Atrazine | Farm chemical | 3 µg/L | 2 | 0 of 2 | not detected | 0 |
| Alachlor | Farm chemical | 2 µg/L | 2 | 0 of 2 | not detected | 0 |
| Chromium | Metal | 100 µg/L | 2 | 0 of 2 | not detected | 0 |
| Cadmium | Metal | 5 µg/L | 2 | 0 of 2 | not detected | 0 |
| Barium | Metal | 2,000 µg/L | 2 | 2 of 2 | 102 µg/L | 0 |
| Mercury | Metal | 2 µg/L | 2 | 0 of 2 | not detected | 0 |
| Selenium | Metal | 50 µg/L | 2 | 0 of 2 | not detected | 0 |
| Thallium | Metal | 2 µg/L | 2 | 0 of 2 | not detected | 0 |
Non-detects count as zero in the highest-result column.
Source: EPA Six-Year Review 4 compliance monitoring data, 2012 to 2019, finished water.
Bacteria in the pipes
From 2012 to 2019, 0 of 2,584 routine total coliform samples taken in the distribution system at Oxford City tested positive (0%); in 2019, the last year on file, 0 of 324 did. E. coli was never found in the 13 samples tested for it.
A positive coliform test is a warning sign, not a violation by itself. E. coli is a sign that human or animal waste may have reached the water. Coliform counts are routine samples only; E. coli counts include repeat samples.
Source: EPA Six-Year Review 4 compliance monitoring data, 2012 to 2019, distribution-system presence/absence tests for total coliform and E. coli.
Fluoride
The Ohio Department of Health's report to the CDC (My Water's Fluoride) says Oxford City adjusts the fluoride level to the recommended level for preventing tooth decay.
EPA's treatment table lists fluoridation among the steps at Oxford City.
Measured fluoride: 0.98 mg/L on average at the plant's entry points in 2017 (in the range dentists aim for); samples ran from 0.98 to 1.09 mg/L across 2 samples in 2012 to 2019.
The recommended level for preventing tooth decay is 0.7 mg/L; the federal limit is 4 mg/L. The treatment list is what each system registered with EPA and can lag a plant upgrade.
Source: CDC My Water's Fluoride (fluoridation status as reported by the Ohio Department of Health, fetched September 2026); EPA Safe Drinking Water Information System (SDWIS) treatment table; EPA Six-Year Review 4 compliance monitoring data, 2012 to 2019, entry-point fluoride samples.
Lithium
Lithium was not detected in 2 UCMR 5 samples at Oxford City, last sampled in 2024 (the method reports from 9 µg/L).
Lithium is not regulated. EPA's draft health reference level is 10 µg/L, and it occurs naturally in deep groundwater, so well systems in the northwest run highest.
Source: EPA UCMR 5 occurrence data (final release, August 2026), samples from 2023 to 2025.
Water and sewer bills
Ohio EPA's 2023 rate survey puts the water bill at Oxford City for a household using 5,000 gallons a month at $315 a year, about $26 a month.
The sewer bill in the same survey is $374 a year at 5,000 gallons a month.
| Use | Water, per year | Sewer, per year |
|---|---|---|
| 2,500 gallons a month | $213 | $210 |
| 5,000 gallons a month | $315 | $374 |
| 8,000 gallons a month | $438 | $570 |
The survey lists it as “Oxford”. These are inside-city rates and annual bills at the use shown.
Source: Ohio EPA 2023 Sewer and Water Rate Survey (Ohio State University, May 2025).
How well the service area is mapped
The service area drawn on the map for Oxford City comes from the utility's own map.
Counting the people who live in the ZIP codes it overlaps, this atlas estimates 22,203 residents are inside the boundary, 93% of the 24,000 people Oxford City reports serving.
The resident count is an estimate from 2020 Census ZIP-code populations, not a count of customers.
Source: EPA Service Area Boundaries; resident estimate by this atlas from ZIP-code overlap.
Photograph
On the map
Show this system's territory on the map — 1 ZIP code in all.
Sources
U.S. EPA SDWIS and Community Water System Service Area Boundaries (v3, 2026), Ohio EPA primacy data, 2020 census blocks: the system serving most residents, traced through purchases to the treating utility; Ohio EPA 2023 Sewer and Water Rate Survey (Ohio State, May 2025) for household bills; Ohio EPA DEFA loan awards since 2016 for the loans paragraph · EPA SDWIS · EPA service area boundaries · Ohio EPA drinking water · Ohio EPA rate survey
EPA's own record for this system: Enforcement and Compliance History report for OH0902312 (EPA ECHO).
Oxford City's own pages: oxfordwater.com, cityofoxford.org
Notable facts: oxfreepress.com, cityofoxford.org, oxfreepress.com, cityofoxford.org
History: oxfreepress.com, oxfreepress.com, oxfreepress.com, cityofoxford.org
Water quality: cityofoxford.org, oxfreepress.com
Planned work: oxfreepress.com
Water pressure: cityofoxford.org, cityofoxford.org
Capital projects: oxfreepress.com, cityofoxford.org
Rates: cityofoxford.org, cityofoxford.org, oxfreepress.com, oxfordwater.com
Sewers: cityofoxford.org, oxfreepress.com
Treatment: cityofoxford.org, cityofoxford.org, oxfreepress.com
Supply stress: cityofoxford.org, oxfreepress.com, oxfreepress.com
