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WaterVerge

Water quality report · updated Jul 2026

Is Colbert, OK Tap Water Safe to Drink?

Graded C+ — but Copper was detected above EPA limits. Here's what's in the water and how to remove it. What to do ↓

1 contaminant over a legal limit
4.4 ppb lead, 90th percentile · low
5 unresolved violations
2K people served by 1 water system

PWSID OK2000716 · moderate data confidence · local government utility

Reviewed by WaterVerge Editorial Team · Last updated July 2026
C 68 / 100

#126 of 357Oklahoma cities
How we grade →

01The verdict: is Colbert water safe?

Colbert's drinking water has significant quality concerns based on EPA testing data. With a grade of C+ (68/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 2,312 residents using groundwater (wells).

The concern

Copper is over its legal limit

Measured at 1.68 mg/L against the EPA Action Level of 1.3 mg/L. The ledger below shows how far over — and which filter removes it.

See the measurement ↓
The good news

Lead is well under the limit

90th-percentile lead is 4.4 ppb — beneath the 15 ppb federal action level and under the 5 ppb watch threshold.

See the trend ↓
Keep watching

16 violations 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 ↓

Colbert's drinking water received a grade of C+ (68 out of 100), indicating fair water quality. The city's 1 water system serves approximately 2,312 residents using groundwater.

Lead levels were measured at 4.4 ppb (90th percentile), well within EPA limits. This system has not yet been tested for PFAS under the EPA UCMR 5 program. The system has 48 violations on record, including 4 health-based violations. 5 remain unresolved.

Colbert ranks #126 out of 357 cities in Oklahoma for water quality, placing it mid-range in the state. Colbert 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. As a small community water system, Colbert may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities. The system has seen 16 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.

How the 68/100 breaks down Methodology →
ViolationsHistorical violation record including health-based and monitoring violations.
24 / 45D
Lead & CopperLead at 4.4 ppb (90th percentile).
14 / 20C
ContaminantsPFAS + legacy contaminant analysis.
17 / 20B
ComplianceMonitoring and reporting compliance with EPA regulations.
8 / 10B
Source RiskWater source: Groundwater.
5 / 5A

02What's in Colbert's water

Every contaminant flagged in Colbert, 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.

2 detections · sorted by % of legal limit
Over the limit Elevated — watch Within limits
0 50% LEGAL LIMIT 150%

Over Limit — EPA Action Level: 1.3 mg/L

Exceeds the EPA action level. Copper leaches from household plumbing — flush taps for 30 seconds before drinking, and consider a certified filter.
Exceeds Limit What to do →
2 contaminants tested under EPA SDWIS, LCR and UCMR programs · 2 detected · not yet tested for PFAS under UCMR 5

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 4.4 15 ppb Inorganic Safe
Copper (90th percentile) 1.68 1.3 mg/L Inorganic Over Limit
Data source: EPA SDWIS, UCMR 5, local utility CCR.

03Colbert'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 48 violations on record, including 4 health-based violations. 5 remain unresolved.

6 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.

1 health-based in 10 yrs 15 monitoring & paperwork 3 still unresolved
UpdateWater quality data updatedLatest EPA compliance and testing data incorporated into Colbert's water quality assessment. Grade: C+ (68/100).
Violation2 drinking water violations recordedContaminants: Revised Total Coliform Rule, Chlorine.Resolved
Violation1 drinking water violation recordedContaminants: Consumer Confidence Rule.Open
Violation2 drinking water violations recordedContaminants: Revised Total Coliform Rule, Chlorine.Resolved
DisasterHURRICANE KATRINA EVACUATIONFederal disaster declaration (FEMA DR-3219). Hurricane event — may have impacted local water infrastructure.
DisasterSEVERE STORMS & FLOODINGFederal disaster declaration (FEMA DR-649). Flood event — may have impacted local water infrastructure.
Lead, 90th percentileppb · lower is better
0102030EPA action level · 15 ppb1993 — 11 ppb1994 — 6 ppb1995 — 12 ppb1996 — 17 ppb1997 — 18 ppb1998 — 11 ppb1999 — 8 ppb2000 — 14 ppb2001 — 6 ppb2002 — 6 ppb2003 — 24 ppb2005 — 6.5 ppb2007 — 7.8 ppb2009 — 7.4 ppb2010 — 6.3 ppb2011 — 0 ppb2012 — 0 ppb2013 — 6.4 ppb2016 — 0 ppb2019 — 5.4 ppb2022 — 2.5 ppb2023 — 4.4 ppb114.4199319982003201120222023

Down 6.6 ppb since 1993. Latest reading: 4.4 ppb (2023) — 29% of the action level. Sampled at higher-risk homes (90th percentile).

Copper, 90th percentilemg/L · lower is better
0123EPA action level · 1.3 mg/L1995 — 1.8 mg/L1997 — 1.7 mg/L2000 — 2.2 mg/L2003 — 2.5 mg/L2005 — 1.7 mg/L1.81.719951997200020032005

Down 0.10 mg/L since 1995. The latest reading (1.7 mg/L, 2005) is over the action level. Sampled at higher-risk homes (90th percentile).

04Where Colbert's water comes from

Colbert's drinking water is drawn from underground aquifers through wells.

Source

Groundwater

Underground aquifers reached by wells — naturally filtered, but can carry minerals like arsenic and nitrate.

Treatment

Local treatment

Groundwater generally needs less treatment — typically disinfection and, where needed, mineral removal.

Distribution

1 system

1 water system, operated under local government ownership.

Delivery

2,312 people

Residents served across Colbert'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 2,312 people through 1 water system.

System namePWSIDPopulationSource
COLBERT PUA OK2000716 2,312 Groundwater

Water bodies near Colbert

Red Rv At Denison Dam Nr Denison · river

These water bodies shape the regional watershed and can indirectly affect groundwater quality.

05Pressure on Colbert'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

Present — monitored

4 facilities within 10 miles reported 175 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.

AAAR DENISON I — zinc compounds 175 lb · 5.9 mi
ROLL-OFFS USA 0 lb · 9.9 mi
FLORESTONE LLC 0 lb · 5.6 mi
+ 1 more facilities

Flood & storm history

Recurring — declared disasters

3 federal disaster declarations on record for Bryan County. Flooding and severe storms can overwhelm treatment plants, cause sewage overflows, and push runoff into supplies.

HURRICANE KATRINA EVACUATION Sep 2005 · DR-3219
SEVERE STORMS & FLOODING Nov 1981 · DR-649
SEVERE STORMS & FLOODING Jan 1972 · DR-317

06How Colbert compares

Scores for nearby Oklahoma cities on one line, with the average marked.

Colbert (this city)
68 · C+
Tulsa
48.5 · D
Lawton
44.4 · F
Broken Arrow
43.9 · F
Oklahoma City
38.6 · F
Norman
38.4 · F

dashed line = Oklahoma average (45/100)

Colbert scores 68/100above the Oklahoma average of 45/100. It outscores 9 of 10 nearby cities. Full Oklahoma rankings →

Bryan water quality rankings
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 Colbert's water — not generic advice.

Because of copper

Filter drinking & cooking water

NSF-certified water filter. Copper exceeds the EPA action level of 1.3 mg/L

Compare tested filters →
Because lead was detected

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 →
Stay informed

Watch for Colbert 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 Colbert, OK tap water safe to drink?

Colbert's water quality earned a grade of C+ (68/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #126 out of 357 cities tested in Oklahoma.

What contaminants are in Colbert's water?

Lead was measured at 4.4 ppb (90th percentile). 48 violations are on record.

How is Colbert'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 Colbert?

Based on current data, basic filtration should suffice for additional peace of mind.

Where does Colbert's water come from?

Colbert's water is sourced from Groundwater. The city has 1 water system serving approximately 2,312 residents.

What health violations has Colbert's water system had?

Colbert has 4 health-based violations on record. The most recent violation was recorded in September 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 5 violations remain unresolved.

Is Colbert's groundwater at risk of contamination?

Colbert 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 48 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 Colbert's water compare to other cities?

Colbert ranks #126 out of 357 cities in Oklahoma (better than 65% of state cities) and #10977 out of 15382 cities nationally (29th percentile). The grade of C+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.

Does Colbert's small water system affect quality?

Colbert's system serves approximately 2,312 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 48 violations on record.

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About Colbert, OK: Colbert is a town in Bryan County, Oklahoma, United States. As of the 2020 census, Colbert had a population of 1,027. It was incorporated in 1939. Median household income $53,600 · median home value $77,743 · median age 43.9 · 58.8% homeowners · 18.5% college educated. Wikipedia → Service area: 1 ZIP code across Bryan.
Show ZIP codes 74733
Sources: EPA SDWIS & ECHO · UCMR 3–5 · Lead & Copper Rule samples · EPA TRI · U.S. Drought Monitor · FEMA declarations. Data last updated Jul 2026. Analysis by the WaterVerge Editorial Team · methodology.