01The verdict: is Mannsville water safe?
Mannsville's drinking water has significant quality concerns based on EPA testing data. With a grade of A- (87.8/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 587 residents using groundwater (wells).
Chlorate is over its legal limit
Measured at 700.0 µg/L against the EPA Lifetime HA of 210 µg/L. The ledger below shows how far over — and which filter removes it.
See the measurement ↓Top half in Oklahoma
Mannsville ranks #26 of 357 graded Oklahoma cities.
See the comparison ↓1 violation in the last five years
Recent compliance history is the best predictor of future problems — the year-by-year record is below.
See the record ↓Mannsville's drinking water received a grade of A- (87.8 out of 100), indicating good water quality. The city's 1 water system serves approximately 587 residents using groundwater.
Lead levels were measured at 5.9 ppb (90th percentile), which is within EPA limits but above recommended levels. This system has not yet been tested for PFAS under the EPA UCMR 5 program. The system has 72 violations on record, including 4 health-based violations. 10 remain unresolved.
Mannsville ranks #26 out of 357 cities in Oklahoma for water quality, placing it one of the best in the state. Mannsville relies on groundwater, which is generally less vulnerable to surface contamination but can be affected by naturally occurring minerals like arsenic and nitrate, as well as agricultural and industrial runoff. Hexavalent chromium (chromium-6) was detected at 0.41 µg/L in UCMR 3 testing. While below California's 10 µg/L limit and with no federal MCL set, residents sensitive to this contaminant may consider reverse osmosis filtration. While lead levels are within EPA limits, they are above the recommended 5 ppb threshold that health organizations consider ideal. A point-of-use filter adds an extra layer of protection. As a small community water system, Mannsville may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
02What's in Mannsville's water
Every contaminant flagged in Mannsville, on one shared scale: distance to its own legal limit. The red line is the limit — anything past it is out of compliance, and the closer a bar gets, the less headroom the system has.
Full contaminants report
| Contaminant | Detected Level | EPA Limit | Unit | Category | Status |
|---|---|---|---|---|---|
| Lead (90th percentile) LeadHeavy Metal A toxic heavy metal that can leach into drinking water from older pipes, solder, and fixtures. No amount of lead in water is considered safe. Health EffectsBrain and nervous system damage in children, kidney damage, high blood pressure, and reproductive problems in adults. EPA Limit15 ppb action level Common SourcesCorrosion of lead pipes, lead solder, brass faucets, and household plumbing. | 5.9 | 15 | ppb | Inorganic | Safe |
Cities ranked by 90th-percentile lead PF PFAS in Oklahoma
Cities ranked by compounds detected Cu Copper in Oklahoma
Cities ranked by 90th-percentile copper
03Mannsville's ten-year track record
Each box is one year. A green check means no EPA violations; a numbered badge counts that year's violations — red if any were health-based, amber if they were monitoring or paperwork issues. The system has 72 violations on record, including 4 health-based violations. 10 remain unresolved.
7 of the last ten years were clean. The numbered years had EPA violations — red when any were health-based, amber when they were paperwork or missed-testing issues.
▲ Up 5.9 ppb since 1993. Latest reading: 5.9 ppb (2025) — 39% of the action level. Sampled at higher-risk homes (90th percentile).
04Where Mannsville's water comes from
Mannsville's drinking water is drawn from underground aquifers through wells.
Groundwater
Underground aquifers reached by wells — naturally filtered, but can carry minerals like arsenic and nitrate.
Local treatment
Groundwater generally needs less treatment — typically disinfection and, where needed, mineral removal.
1 system
1 water system, operated under local government ownership.
587 people
Residents served across Mannsville's service area.
Groundwater is naturally filtered through rock and soil layers, generally requiring less treatment than surface water. However, it can contain naturally occurring contaminants like arsenic, radon, and minerals. Agricultural activity, septic systems, and industrial operations near well fields can introduce nitrates, pesticides, and volatile organic compounds. The system is operated by local government ownership and serves approximately 587 people through 1 water system.
| System name | PWSID | Population | Source |
|---|---|---|---|
| MANNSVILLE PUBLIC WORKS AUTHORITY | OK2003505 | 587 | Groundwater |
Water bodies near Mannsville
These water bodies shape the regional watershed and can indirectly affect groundwater quality.
05Pressure on Mannsville's watershed
Outside forces that shape what reaches the treatment plant. None of these is a verdict on the tap by itself — but each adds pressure worth knowing about.
Industrial discharge
1 facility within 10 miles reported 0 lb released to surface water in the latest EPA Toxics Release Inventory. Proximity doesn't equal tap contamination — treatment and hydrology decide — but it's pressure on the watershed.
Flood & storm history
3 federal disaster declarations on record for Johnston County. Flooding and severe storms can overwhelm treatment plants, cause sewage overflows, and push runoff into supplies.
Drought
Johnston County is in D1 (moderate drought) per the U.S. Drought Monitor (week of Jul 2026). Drought can raise disinfection-byproduct levels and taste/odor issues as utilities draw from lower reservoirs.
06How Mannsville compares
Scores for nearby Oklahoma cities on one line, with the average marked.
dashed line = Oklahoma average (45/100)
Mannsville scores 87.8/100 — above the Oklahoma average of 45/100. It outscores 10 of 10 nearby cities. Full Oklahoma rankings →
38.6 / 100DTulsa, OK
48.5 / 100FBroken Arrow, OK
43.9 / 100FNorman, OK
38.4 / 100FLawton, OK
44.4 / 100FEdmond, OK
34.9 / 100
Compare all cities in the county — grades, violations, and contaminant data side by side.→
07What to do at home
Steps matched to what testing actually found in Mannsville's water — not generic advice.
Filter drinking & cooking water
NSF-certified water filter. Lead detected at 5.9 ppb
Compare tested filters →Flush taps & check your service line
Lead leaches from pipes as water sits. Run cold water 30 seconds before drinking (especially mornings), and ask the utility whether your address still has a lead service line.
Lead risks explained →Watch for Mannsville alerts
This area has a history of flood declarations — after severe weather, watch for boil-water advisories from the utility, and check the live alerts on this page.
All water alerts →Frequently asked questions
Is Mannsville, OK tap water safe to drink?
Mannsville's water quality earned a grade of A- (87.8/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #26 out of 357 cities tested in Oklahoma.
What contaminants are in Mannsville's water?
Lead was measured at 5.9 ppb (90th percentile). 72 violations are on record.
How is Mannsville's water quality grade calculated?
The grade is based on four factors: violation history (40%), lead and copper levels (25%), PFAS contamination (25%), and regulatory compliance (10%). The score is also adjusted based on how complete the available data is. See our methodology page for full details.
Do I need a water filter in Mannsville?
While lead levels are within EPA limits, a filter adds extra protection. Based on current data, basic filtration should suffice for additional peace of mind.
Where does Mannsville's water come from?
Mannsville's water is sourced from Groundwater. The city has 1 water system serving approximately 587 residents.
What health violations has Mannsville's water system had?
Mannsville has 4 health-based violations on record. The most recent violation was recorded in October 2022. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 10 violations remain unresolved.
Is Mannsville's groundwater at risk of contamination?
Mannsville uses groundwater, which can be affected by naturally occurring contaminants like arsenic, radon, and nitrate, as well as agricultural runoff and industrial activity. The system has 72 violations on record that may relate to groundwater quality. Groundwater systems are generally less susceptible to surface contamination but should be monitored for emerging contaminants like PFAS.
How does Mannsville's water compare to other cities?
Mannsville ranks #26 out of 357 cities in Oklahoma (better than 93% of state cities) and #3825 out of 15382 cities nationally (75th percentile). The grade of A- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.
Does Mannsville's small water system affect quality?
Mannsville's system serves approximately 587 residents. Small community water systems (under 3,300 people) may have fewer financial resources for infrastructure upgrades and advanced treatment technologies. However, they are held to the same EPA drinking water standards as larger systems. This system has 72 violations on record.