Water system
Guernsey Co. Water Dept.
EPA ID OH3000603 · Guernsey County · 8,891 people served · owned by a local government
Guernsey Co. Water Dept. buys its water from Cambridge, City Of.
The system's record
- Water bodies
- Wills Creek, Cambridge Reservoir
- Raw intakes
- Cambridge Reservoir
Wills Creek - Serves
- 10,520 people · Guernsey County
- EPA ID
- OH3000111
About this area's water Cambridge, City Of
Did you know
- Cambridge sells more water than it drinks: about 10,360 people are served directly, but wholesale deliveries to the Western Guernsey Regional Water District and the Guernsey County Water Department bring the combined…
- The city keeps an emergency interconnection with the village of Byesville; it was not needed at all during 2024.
- The 2024 CCR reports 2023 average hardness of 305 mg/L, or 17.82 grains per gallon — hard water, typical of the region's limestone and shale geology.
- There is a self-serve bulk water vending station on Oxford Avenue for anyone hauling water to fill a pool or supplement a private well; you need a vending card from the utilities office.
- The Lead and Copper Rule service line inventory is not online — you have to go to the water treatment plant at 1700 Burgess Ave to look up what your service line is made of.
Source: cambridgeoh.org
History6
- 1798A ferry was established where Zane's Trace crossed Wills Creek, at the site that became Cambridge.
- 1803The first bridge authorized by the legislature of the Northwest Territory was built across Wills Creek here.
- 1998The Cambridge area experienced massive flooding in late June.
- 2005Ohio EPA completed the source water assessment still cited in the city's CCR, finding the Wills Creek supply susceptible to leaking underground storage facilities, oil and gas wells, mining runoff…
- 2023Ohio BUILDS Round 5 awarded the city $3,834,975 in July for waterline and service improvements including lead line removal and elimination of dead-end mains.
- 2024The city held an unconditional Ohio EPA license to operate, reported no monitoring, reporting or treatment technique violations, and recorded zero positive total coliform results on 120 samples.
Source: en.wikipedia.orgcambridgeoh.orgcontent.govdelivery.com
Treatment & pressure
How it is treated
The 2024 CCR does not publish a step-by-step treatment train. What it documents is a conventional surface-water plant at 1700 Burgess Ave operating under the turbidity treatment technique (100% of 2024 samples met the standard; highest reading 0.22 NTU) and TOC removal requirements, with fluoride…
Source: cambridgeoh.org
Water pressure
No system-wide psi figure is published. The CCR's boil-order FAQ notes that Ohio EPA recommends issuing a boil order any time distribution pressure falls below 20 psi — a…
Source: cambridgeoh.org
What it costs
Cambridge does not publish its water or sewer rate schedule online. The Utilities Office page states only that rates are available upon request; the office is at 828 Wheeling…
Source: cambridgeoh.org
Water quality & impurities10
| Contaminant | Level | Limit | Year |
|---|---|---|---|
| Total Trihalomethanes (TTHM) Range 35.5-91.3 ppb across sites — individual samples exceeded 80 ppb even though the compliance average did not. No… | 63.3 ppb | 80 (MCL) | 2024 |
| Haloacetic Acids (HAA5) Range 27.6-59.2 ppb; running close to the limit. No violation. | 51.2 ppb | 60 (MCL) | 2024 |
| Lead (90th percentile) Sampled at customer taps 6/1/24-9/3/24; 0 of 60 samples exceeded the action level; range 0-3.36 ppb. | 1.04 ppb | 15 (action… | 2024 |
| Copper (90th percentile) 0 of 60 samples exceeded the action level; range 0.00484-0.0659 ppm. | 0.0372 ppm | 1.3 (action… | 2024 |
| Nitrate Range 0-0.13 ppm; fertilizer runoff and natural deposits. | 0.13 ppm | 10 (MCL) | 2024 |
| Fluoride Range 0.80-1.25 ppm; added for dental health. | 1.01 ppm | 4 (MCL) | 2024 |
| Barium Naturally occurring; also drilling wastes and metal refinery discharge — relevant in a county with oil and gas activity. | 0.042 ppm | 2 (MCL) | 2024 |
| PFOA (UCMR5) Average of 0.0055 ug/L (5.5 ng/L), range 0.0054-0.0056 — above the 4 ng/L federal PFOA standard adopted in 2024, whose… | 0.0055 ug/L | no MCL applies… | 2024 |
| Other PFAS (UCMR5: PFOS, PFHxA… PFBA averaged 0.0038 ug/L; PFOS, PFHxA, GenX and PFPeA each averaged 0.0004 ug/L with maxima of 0.0011-0.0013 ug/L. | 0.0004-0.0038 ug/L | no MCL (UCMR5… | 2024 |
| Lithium (UCMR5) Range 0-7.14 ug/L; naturally occurring and can concentrate in brine waters. | 2.38 ug/L | no MCL (UCMR5… | 2024 |
Source: cambridgeoh.org
EPA compliance record · Guernsey Co. Water Dept.
Lead at the tap: 90th-percentile result 0 ppb in 2023 (action level 15 ppb).
EPA health-based violations since 2015:
- 2024Haloacetic acids (HAA5) · above the legal limit on average · measured 0.063 MG/L (limit 0.06 MG/L) · returned to compliance
- 2017Total trihalomethanes (TTHM) · above the legal limit on average · measured 0.099 MG/L (limit 0.08 MG/L) · returned to compliance
EPA's count of 4 includes 2 repeat quarterly violations of the problems listed.
4 violations of any kind logged since 2020: 2 for required testing that was missed or reported late; 1 for a report, record or notice that was missing, late or incomplete (the yearly water quality report, a public notice, lead line records); 1 health-based.
EPA compliance record · Cambridge, City Of (treats the water)
Lead at the tap: 90th-percentile result 0 ppb in 2025 (action level 15 ppb).
EPA health-based violations since 2015:
- 2019Surface Water Treatment Rule · required treatment not met · returned to compliance
- 2017Total trihalomethanes (TTHM) · above the legal limit on average · measured 0.084 MG/L (limit 0.08 MG/L) · returned to compliance
- 2016Total trihalomethanes (TTHM) · above the legal limit on average · measured 0.081 MG/L (limit 0.08 MG/L) · returned to compliance
Projects & plans2
Recent and current work
- Citywide waterline and service improvements with lead line removal · $3.8 million · 2023 · planned
Ohio BUILDS Round 5 grant awarded July 2023 for improvements to waterlines and services on several streets, including lead line removal and elimination of… - Guernsey County sewer expansion and improvements in Cambridge (Beech Meadows) · $2.7 million · 2023 · planned
Awarded to the Guernsey County Board of Commissioners, not the city: lining two subdivisions' sewer networks (11,490 lf of 8-inch lining), 8,000 lf of 6-inch…
Source: content.govdelivery.com
Supply stress
Cambridge draws from Wills Creek, and Ohio EPA's 2005 source water assessment — still the current one cited in the CCR — flags that supply as susceptible to leaking underground storage facilities, oil and gas wells, mining runoff, scattered pockets of small unsewered areas, spills from local industries into Wills Creek and its…
Source: cambridgeoh.org
Sewers
Sanitary
The City of Cambridge operates its own sewer system, billed alongside water through the Utilities Office at 828 Wheeling Avenue. Plant location, capacity, receiving stream, NPDES permit details and any CSO status are not published on the city's website, and rates are available only on request. Separately, Guernsey County received a…
Sourcesverified
Compiled from the utility's own reports and public records, then independently re-checked against primary sources.
Present in 2 ZIP codes
Serves
Main water supplier in 1 ZIP code
- 43768 · Old Washington34% of residents
Also present in 1 more ZIP code
- 43725 · Cambridge2% 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
Guernsey Co. Water Dept. buys its water from Cambridge, City Of.
No other system is on record buying water from Guernsey Co. Water Dept..
What the records show about Guernsey Co. Water Dept.
Who runs it
EPA's record describes Guernsey Co. Water Dept. as owned by a local government. It has 3,660 service connections and serves 8,891 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 740-432-9200.
Source: EPA Safe Drinking Water Information System (SDWIS), water system record.
How the water is treated
Guernsey Co. Water Dept. buys water that Cambridge, City Of treats first, so the steps that count are the seller's. EPA's treatment table registers these steps for Cambridge, City Of: aeration, corrosion control, coagulation and settling, chlorine disinfection, iron and manganese removal, fluoridation, powdered activated carbon, 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 counts 4 health-based violations for Guernsey Co. Water Dept. since 2015. Health-based means a contaminant above its legal limit or a required treatment step not carried out. They fall into 2 separate problems (one contaminant or rule in one year); the table lists them all.
EPA logs a violation for each compliance period a problem lasts, so the count of 4 includes 2 repeat entries of the problems listed.
EPA logs 4 violations of any kind since 2020: 2 for required testing that was missed or reported late; 1 for a report, record or notice that was missing, late or incomplete (the yearly water quality report, a public notice, lead line records); 1 health-based.
| Year | Contaminant or rule | Kind | Measured | Limit | Status in EPA's record |
|---|---|---|---|---|---|
| 2024 | Haloacetic acids (HAA5) | above the legal limit on average | 0.063 mg/L | 0.06 mg/L | returned to compliance |
| 2017 | Total trihalomethanes (TTHM) | above the legal limit on average | 0.099 mg/L | 0.08 mg/L | returned to compliance |
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 2023, the 90th-percentile lead result at Guernsey Co. Water Dept. was 0 ppb, under both the current 15 ppb action level and the 10 ppb level that applies from 2027. A result of 0 means at least nine in ten of the homes sampled had no lead detected.
EPA has 3 sampling periods on file for Guernsey Co. Water Dept. since 2016, the first ending in 2017; 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 Guernsey Co. Water Dept. sent EPA, 4,025 lines are counted.
| Material | Lines |
|---|---|
| Lead | 6 |
| Galvanized, needing replacement | 0 |
| Unknown material | 424 |
| Not lead | 3,595 |
| All lines | 4,025 |
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 4 samples of the water entering the pipes of Guernsey Co. Water Dept. in 2025 and measured 29 PFAS.
The highest PFOA or PFOS result, 9.8 ng/L, is at or above the federal limit of 4 ng/L that EPA set in 2024. Systems have until 2029 to comply, and in May 2026 EPA proposed letting systems apply for two more years. One sample over the limit is not a violation: compliance is judged on a running annual average.
The highest PFAS result was PFOA 9.8 ng/L.
Ohio EPA's own statewide sampling tested 1 plant of Cambridge, City Of (latest sample April 2021). The highest result was PFOA at 5.2 ppt (ppt is the same unit as ng/L), against Ohio's action level of 70 ppt. Those action levels are the ones Ohio EPA used for the survey; the 2024 federal limit for PFOA and PFOS is 4 ng/L.
Ohio EPA's current sampling status map lists 1 plant of Cambridge, City Of as sampled, most recently July 2026.
| Compound | Highest result | Federal limit |
|---|---|---|
| PFOA | 9.8 ng/L | 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 Guernsey Co. Water Dept.'s samples in 2019, the last year it was sampled, was 66.8 µg/L. The worst yearly average was 80.9 µg/L and the highest single sample was 129.2 µg/L, from 59 samples taken from 2012 to 2019. A yearly average over 80 is not itself a violation, because compliance is judged site by site.
For HAA5, the average in the last year sampled was 48.1 µg/L. The worst yearly average was 48.1 µg/L and the highest single sample was 65 µg/L, from 59 samples.
| Byproduct | Limit | Latest yearly average | Worst yearly average | Highest sample | Samples |
|---|---|---|---|---|---|
| TTHM | 80 µg/L | 66.8 µg/L (2019) | 80.9 µg/L | 129.2 µg/L | 59 |
| HAA5 | 60 µg/L | 48.1 µg/L | 48.1 µg/L | 65 µg/L | 59 |
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
The water Guernsey Co. Water Dept. buys is treated by Cambridge, City Of, so the results below are Cambridge, City Of's.
Nitrate: the highest of 95 samples was 4.7 mg/L (as nitrogen) in 2015; in 2019, the last year sampled, the highest was 0.52 mg/L. No sample was over the limit of 10 mg/L. Nitrate above 10 is unsafe for infants.
Arsenic was not detected in 9 samples (limit 10 µg/L).
| Contaminant | Samples | Highest result | Limit | Samples over limit |
|---|---|---|---|---|
| Nitrate (as nitrogen) | 95 | 4.7 mg/L | 10 mg/L | 0 |
| Arsenic | 9 | 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 of Cambridge, City Of.
Solvents and fuels
The water Guernsey Co. Water Dept. buys is treated by Cambridge, City Of, so the results below are Cambridge, City Of's.
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 8 samples each.
| Compound | Limit | Samples | Detected in | Highest result | Samples over limit |
|---|---|---|---|---|---|
| Benzene | 5 µg/L | 8 | 0 of 8 | not detected | 0 |
| Carbon tetrachloride | 5 µg/L | 8 | 0 of 8 | not detected | 0 |
| 1,2-dichloroethane | 5 µg/L | 8 | 0 of 8 | not detected | 0 |
| Trichloroethylene (TCE) | 5 µg/L | 8 | 0 of 8 | not detected | 0 |
| Tetrachloroethylene (PCE) | 5 µg/L | 8 | 0 of 8 | not detected | 0 |
| Vinyl chloride | 2 µg/L | 8 | 0 of 8 | 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 of Cambridge, City Of.
Farm chemicals and metals
The water Guernsey Co. Water Dept. buys is treated by Cambridge, City Of, so the results below are Cambridge, City Of's.
EPA's file holds results for 8 of the nine herbicides and metals it checked. Detected: chromium in 1 of 9 samples, highest 1.28 µg/L (limit 100); barium in 1 of 9 samples, highest 31 µg/L (limit 2,000). Not detected: atrazine in 8 samples, alachlor in 8 samples, cadmium in 9 samples, mercury in 9 samples, selenium in 9 samples, thallium in 9 samples.
| Substance | Kind | Limit | Samples | Detected in | Highest result | Samples over limit |
|---|---|---|---|---|---|---|
| Atrazine | Farm chemical | 3 µg/L | 8 | 0 of 8 | not detected | 0 |
| Alachlor | Farm chemical | 2 µg/L | 8 | 0 of 8 | not detected | 0 |
| Chromium | Metal | 100 µg/L | 9 | 1 of 9 | 1.28 µg/L | 0 |
| Cadmium | Metal | 5 µg/L | 9 | 0 of 9 | not detected | 0 |
| Barium | Metal | 2,000 µg/L | 9 | 1 of 9 | 31 µg/L | 0 |
| Mercury | Metal | 2 µg/L | 9 | 0 of 9 | not detected | 0 |
| Selenium | Metal | 50 µg/L | 9 | 0 of 9 | not detected | 0 |
| Thallium | Metal | 2 µg/L | 9 | 0 of 9 | 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 of Cambridge, City Of.
Bacteria in the pipes
From 2012 to 2019, 3 of 970 routine total coliform samples taken in the distribution system at Guernsey Co. Water Dept. tested positive (0.31%); in 2019, the last year on file, 1 of 120 did. E. coli was never found in the 3 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 Guernsey Co. Water Dept. buys its water from Cambridge, City Of, a system that adjusts the fluoride level to the recommended level for preventing tooth decay.
EPA's treatment table lists fluoridation among the steps at Cambridge, City Of, which treats the water Guernsey Co. Water Dept. buys.
Measured fluoride: 1.05 mg/L on average leaving the plants of Cambridge, City Of, which supplies Guernsey Co. Water Dept., in 2019 (in the range dentists aim for); samples ran from 0.3 to 1.17 mg/L across 9 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 found in 2 of 4 UCMR 5 samples at Guernsey Co. Water Dept., highest 17 µg/L; detections averaged 13.3, last sampled in 2025.
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.
Algal toxins
The water Guernsey Co. Water Dept. buys is treated by Cambridge, City Of, so the results below are Cambridge, City Of's.
Ohio EPA tests for microcystin, a toxin that harmful algal blooms can release, in raw water at the intake and in treated water.
At the intake, microcystin was detected 2 times in 231 raw-water samples, across 2 bloom seasons (2024 to 2025); the highest raw-water result was 0.414 µg/L on November 20, 2024. The highest raw-water result since 2024 was 0.414 µg/L.
Microcystin was never detected in treated water (105 samples).
In all, 336 samples from 2016 to 2026, the latest on August 12, 2026.
| Water | Samples | Detections | Highest result |
|---|---|---|---|
| Raw water, at the intake | 231 | 2 | 0.414 µg/L |
| Treated water | 105 | 0 | not detected |
The ten-day advisory levels for treated water are 0.3 µg/L for children under six and 1.6 µg/L for everyone else. Any detection at the intake triggers more frequent testing until two clean weeks.
Source: Ohio EPA public water system harmful algal bloom monitoring, 2016 to present (HAB data, fetched September 2026).
How well the service area is mapped
EPA estimated the service area of Guernsey Co. Water Dept. 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 503 residents are inside the boundary, 6% of the 8,891 people Guernsey Co. Water Dept. 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 OH3000603 (EPA ECHO).
