Water system
Knox County Water and Wastewater
EPA ID OH4202012 · Knox County · 7,710 people served
Knox County Water and Wastewater treats its own water from Groundwater wells (4 wells).
The system's record
- Active wells
- 4
- Serves
- 7,710 people · Knox County
- EPA ID
- OH4202012
About this area's water
Water quality & impurities
EPA compliance record
Lead at the tap: 90th-percentile result 2.1 ppb in 2025 (action level 15 ppb).
EPA record: no health-based violations since 2015.
3 violations of any kind logged since 2020: 3 for a report, record or notice that was missing, late or incomplete (the yearly water quality report, a public notice, lead line records).
Present in 2 ZIP codes
Serves
Main water supplier in 1 ZIP code
- 43028 · Howard Township and Howard48% of residents
Also present in 1 more ZIP code
- 43050 · Mount Vernon0% 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
Knox County Water and Wastewater does not buy water from another system on record; it treats its own source water.
No other system is on record buying water from Knox County Water and Wastewater.
What the records show about Knox County Water and Wastewater
Who runs it
EPA's record says Knox County Water and Wastewater has 3,109 service connections and serves 7,710 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 740-397-7041.
Source: EPA Safe Drinking Water Information System (SDWIS), water system record.
How the water is treated
EPA's treatment table registers these steps for Knox County Water and Wastewater: corrosion control, chlorine disinfection, and fluoridation.
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 Knox County Water and Wastewater since 2015.
EPA logs 3 violations of any kind since 2020: 3 for a report, record or notice that was missing, late or incomplete (the yearly water quality report, a public notice, lead line records).
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 Knox County Water and Wastewater was 2.1 ppb, under both the current 15 ppb action level and the 10 ppb level that applies from 2027.
EPA has 9 sampling periods on file for Knox County Water and Wastewater since 2016, the first ending in 2016; no period was above 10 ppb.
Every water system has to inventory its service lines, the pipes from the main to each building. In the inventory Knox County Water and Wastewater sent EPA, 3,179 lines are counted.
| Material | Lines |
|---|---|
| Lead | 0 |
| Galvanized, needing replacement | 0 |
| Unknown material | 0 |
| Not lead | 3,179 |
| All lines | 3,179 |
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 Knox County Water and Wastewater in 2023 and measured 29 PFAS. No PFAS was detected, PFOA and PFOS (federal limit 4 ng/L each) among them.
Ohio EPA's own statewide sampling tested 1 plant of Knox County Water and Wastewater (latest sample October 2020). Not one of the six PFAS tested (PFOA, PFOS, PFHxS, PFNA, GenX and PFBS) was detected.
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 Knox County Water and Wastewater's samples in 2019, the last year it was sampled, was 14.3 µg/L. The worst yearly average was 22.9 µg/L and the highest single sample was 24.7 µg/L, from 16 samples taken from 2012 to 2019.
For HAA5, the average in the last year sampled was 0 µg/L. The worst yearly average was 6 µg/L and the highest single sample was 6.3 µg/L, from 16 samples.
| Byproduct | Limit | Latest yearly average | Worst yearly average | Highest sample | Samples |
|---|---|---|---|---|---|
| TTHM | 80 µg/L | 14.3 µg/L (2019) | 22.9 µg/L | 24.7 µg/L | 16 |
| HAA5 | 60 µg/L | 0 µg/L | 6 µg/L | 6.3 µg/L | 16 |
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 9 samples was 1.54 mg/L (as nitrogen) in 2016; in 2019, the last year sampled, the highest was 1.19 mg/L. No sample was over the limit of 10 mg/L. Nitrate above 10 is unsafe for infants.
Arsenic was not detected in 3 samples (limit 10 µg/L).
| Contaminant | Samples | Highest result | Limit | Samples over limit |
|---|---|---|---|---|
| Nitrate (as nitrogen) | 9 | 1.54 mg/L | 10 mg/L | 0 |
| Arsenic | 3 | 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 3 samples each.
| Compound | Limit | Samples | Detected in | Highest result | Samples over limit |
|---|---|---|---|---|---|
| Benzene | 5 µg/L | 3 | 0 of 3 | not detected | 0 |
| Carbon tetrachloride | 5 µg/L | 3 | 0 of 3 | not detected | 0 |
| 1,2-dichloroethane | 5 µg/L | 3 | 0 of 3 | not detected | 0 |
| Trichloroethylene (TCE) | 5 µg/L | 3 | 0 of 3 | not detected | 0 |
| Tetrachloroethylene (PCE) | 5 µg/L | 3 | 0 of 3 | not detected | 0 |
| Vinyl chloride | 2 µg/L | 3 | 0 of 3 | 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 3 of 3 samples, highest 40.4 µg/L (limit 2,000). Not detected: atrazine, alachlor, chromium, cadmium, mercury, selenium, and thallium, in 3 samples each.
| Substance | Kind | Limit | Samples | Detected in | Highest result | Samples over limit |
|---|---|---|---|---|---|---|
| Atrazine | Farm chemical | 3 µg/L | 3 | 0 of 3 | not detected | 0 |
| Alachlor | Farm chemical | 2 µg/L | 3 | 0 of 3 | not detected | 0 |
| Chromium | Metal | 100 µg/L | 3 | 0 of 3 | not detected | 0 |
| Cadmium | Metal | 5 µg/L | 3 | 0 of 3 | not detected | 0 |
| Barium | Metal | 2,000 µg/L | 3 | 3 of 3 | 40.4 µg/L | 0 |
| Mercury | Metal | 2 µg/L | 3 | 0 of 3 | not detected | 0 |
| Selenium | Metal | 50 µg/L | 3 | 0 of 3 | not detected | 0 |
| Thallium | Metal | 2 µg/L | 3 | 0 of 3 | 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, 1 of 856 routine total coliform samples taken in the distribution system at Knox County Water and Wastewater tested positive (0.12%); in 2019, the last year on file, 0 of 99 did. E. coli was never found in the 1 sample 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 Knox County Water and Wastewater adjusts the fluoride level to the recommended level for preventing tooth decay.
EPA's treatment table lists fluoridation among the steps at Knox County Water and Wastewater.
Measured fluoride: 0.88 mg/L on average at the plant's entry points in 2018 (in the range dentists aim for); samples ran from 0.88 to 1.06 mg/L across 3 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 Knox County Water and Wastewater, last sampled in 2023 (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.
How well the service area is mapped
EPA estimated the service area of Knox County Water and Wastewater with a computer model rather than drawing it from the utility's map, so its edges are approximate.
Counting the people who live in the ZIP codes it overlaps, this atlas estimates 3,716 residents are inside the boundary, 48% of the 7,710 people Knox County Water and Wastewater reports serving. With so much of its territory outside the polygon, part of the system shows on the map as private wells.
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.
On the map
Show this system's territory on the map — 2 ZIP codes 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 OH4202012 (EPA ECHO).
