Water Quality Report · Updated May 12, 2026

OKLAHOMA CITY

Serving 644,000 residents in OKLAHOMA CITY, Oklahoma .

National rank 59th percentile
Oklahoma rank 60th percentile
Data confidence Medium
Quick answer

OKLAHOMA CITY delivers tap water graded C (65/100) by TapWaterSafety.org. The utility serves approximately 644,000 residents in OKLAHOMA CITY, Oklahoma using surface water. The most significant water quality concerns are: Haloacetic acids (HAA9) significantly above health guideline; Total trihalomethanes (TTHMs) significantly above health guideline; Haloacetic acids (HAA5) significantly above health guideline. For questions, the utility can be reached at 405-297-3731.

Data sources for this grade: utilities.csv EWG Tap Water Database ⓘ How did we get this rating?
644,000
People served
1
City served
27
Contaminants detected
15
Above health guidelines
0
EPA violations (5 yr)

Is OKLAHOMA CITY tap water safe to drink?

OKLAHOMA CITY delivers tap water that earns a grade of C (65/100) from TapWaterSafety.org — an average rating, with several contaminants above health guidelines but generally compliant with US legal limits.

The utility serves 644,000 residents in OKLAHOMA CITY, drawing from surface water.

Public testing data identifies 15 contaminants in this water above EWG's health-based guidelines, including: Haloacetic acids (HAA9), Total trihalomethanes (TTHMs), Haloacetic acids (HAA5), Bromodichloromethane, Trichloroacetic acid, Chloroform, Dichloroacetic acid, Dibromoacetic acid, Dibromochloromethane, Radium, combined (-226 and -228), Bromate, Chromium (hexavalent), Nitrate and nitrite, Nitrate, Bromoform. For most residents, a properly certified home filter at the kitchen tap is the most cost-effective way to reduce exposure to whatever's in your water. See our filter recommendations below, matched specifically to this utility's contaminant profile.

Top concerns in this water

Based on the most recent EPA and EWG data, these are the most significant water quality issues for OKLAHOMA CITY.

Haloacetic acids (HAA9) significantly above health guideline

Moderate concern

Haloacetic acids (HAA9) detected at 38.1 ppb, 635x above the EWG health guideline of 0.06 ppb.

Total trihalomethanes (TTHMs) significantly above health guideline

Moderate concern

Total trihalomethanes (TTHMs) detected at 54.7 ppb, 365x above the EWG health guideline of 0.15 ppb.

Haloacetic acids (HAA5) significantly above health guideline

Moderate concern

Haloacetic acids (HAA5) detected at 30.5 ppb, 305x above the EWG health guideline of 0.1 ppb.

Contact OKLAHOMA CITY

Reach the utility directly for service issues, water quality concerns, or to request your Consumer Confidence Report.

Recommended water filters for OKLAHOMA CITY

Filters matched to the specific contaminants in this water supply.

Disclosure: TapWaterSafety earns a commission from purchases made through these links. This does not influence our scoring methodology or filter selection.

Score breakdown

This utility's overall score of 65/100 breaks down across five weighted components. Read the full methodology →

Health Guideline Performance
10 / 40
Legal Compliance
20 / 20
High-Risk Contaminants
18 / 20
Compliance History
10 / 10
Source Water Vulnerability
7 / 10

Contaminants detected — international standards comparison

Every contaminant detected, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal (the strictest US benchmark). Why we show multiple standards →

Contaminant Detected EWG
US health-based
EPA
US legal
EU DWD
Europe
WHO
global
CA PHG
strictest US
Tested
sample year
Status
Haloacetic acids (HAA9)
Disinfection byproduct
38.1 ppb 0.06 635× over
Total trihalomethanes (TTHMs)
Disinfection byproduct
54.7 ppb 0.15 80.0 100 365× over
Haloacetic acids (HAA5)
Disinfection byproduct
30.5 ppb 0.1 60.0 60 305× over
Bromodichloromethane
Disinfection byproduct
10.4 ppb 0.06 173× over
Trichloroacetic acid
Disinfection byproduct
12.7 ppb 0.1 127× over
Chloroform
Disinfection byproduct
40.8 ppb 0.4 102× over
Dichloroacetic acid
Disinfection byproduct
16.5 ppb 0.2 82× over
Dibromoacetic acid
Disinfection byproduct
0.892 ppb 0.03 30× over
Dibromochloromethane
Disinfection byproduct
2.67 ppb 0.1 27× over
Radium, combined (-226 and -228)
Radiological
1.18 pCi/L 0.05 5.0 24× over
Bromate
Disinfection byproduct
2.2 ppb 0.1 10.0 10 10 0.1 22× over
Chromium (hexavalent)
Heavy metal
0.115 ppb 0.02 5.7× over
Nitrate and nitrite
Inorganic
0.236 ppm 0.14 10.0 11.3 11.3 10 1.7× over
Nitrate
Inorganic
0.233 ppm 0.14 10.0 11.3 11.3 10 1.7× over
Bromoform
Disinfection byproduct
0.629 ppb 0.5 1.3× over
Vanadium
Other
2.3 ppb 21.0 Below guideline
Barium
Heavy metal
67.5 ppb 700.0 2000.0 1300 2000 Below guideline
Molybdenum
Other
1.46 ppb 40.0 Below guideline
Manganese
Heavy metal
1.18 ppb 100.0 50 80 Below guideline
Monochloroacetic acid
Disinfection byproduct
0.412 ppb 53.0 Below guideline
Perfluoropentanoic Acid (PFPeA)
PFAS
1.3 ppt 1000.0 Below guideline
Monobromoacetic acid
Disinfection byproduct
0.0137 ppb 25.0 Below guideline
Strontium
Radiological
0.293 ppb 1500.0 Below guideline
Fluoride
Inorganic
0.575 ppm 4.0 1.5 1.5 Below guideline
Germanium
Other
0.0649 ppb Below guideline
Lithium
Other
42.6 ppb Below guideline
Nitrite
Inorganic
0.00338 ppm 1.0 Below guideline

All values in the unit of the detected level. Red cells indicate the detected level exceeds that standard. Some contaminants have limits in some jurisdictions but not others (shown as —). The "Tested" column shows the year each contaminant sample was collected.

Sources: US EPA, EU Drinking Water Directive 2020/2184, WHO Guidelines (4th ed.), California OEHHA PHGs, EWG Tap Water Database.

OKLAHOMA CITY service area

This water system serves 1 community in Oklahoma County, Oklahoma. Click any city for its dedicated tap water quality page.

About this water system

Public Water System ID
OK1020902
Owner type
Local government
Source water
Surface water
Service connections
254,388
Service area
OKLAHOMA CITY, Oklahoma County, Oklahoma