Water Quality Report · Updated May 12, 2026

KENNEWICK CITY OF

Serving 118,164 residents in Kennewick, Washington .

National rank 4th percentile
Washington rank 3th percentile
Data confidence Medium
Quick answer

KENNEWICK CITY OF delivers tap water graded F (47/100) by TapWaterSafety.org. The utility serves approximately 118,164 residents in Kennewick, Washington using surface water. The most significant water quality concerns are: PFAS contamination; Perfluorohexane sulfonate (PFHXS) significantly above health guideline; Total PFOS and PFOA significantly above health guideline; Arsenic significantly above health guideline.

Data sources for this grade: utilities.csv EWG Tap Water Database ⓘ How did we get this rating?
118,164
People served
1
City served
34
Contaminants detected
19
Above health guidelines
0
EPA violations (5 yr)

Is Kennewick tap water safe to drink?

KENNEWICK CITY OF delivers tap water that earns a grade of F (47/100) from TapWaterSafety.org — a poor rating, with significant contamination concerns and/or recent violations.

The utility serves 118,164 residents in Kennewick, drawing from surface water.

Public testing data identifies 19 contaminants in this water above EWG's health-based guidelines, including: Perfluorooctane sulfonate (PFOS), Perfluorohexane sulfonate (PFHXS), Total PFOS and PFOA, Arsenic, Haloacetic acids (HAA9), Total trihalomethanes (TTHMs), Haloacetic acids (HAA5), Bromodichloromethane, Trichloroacetic acid, Chloroform, Dibromochloromethane, Dibromoacetic acid, Dichloroacetic acid, Chromium (hexavalent), Nitrate, Perfluorooctanoic acid (PFOA), Nitrate and nitrite, Bromoform, Chlorate. 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.

Quick actions for Kennewick residents

Top concerns in this water

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

PFAS contamination

Severe concern

Perfluorooctane sulfonate (PFOS), Perfluorooctanoic acid (PFOA) detected. PFAS are persistent chemicals linked to cancer and immune effects with no known safe exposure threshold.

Perfluorohexane sulfonate (PFHXS) significantly above health guideline

Moderate concern

Perfluorohexane sulfonate (PFHXS) detected at 8.67 ppt, 8673x above the EWG health guideline of 0.001 ppt.

Total PFOS and PFOA significantly above health guideline

Moderate concern

Total PFOS and PFOA detected at 9.64 ppt, 1377x above the EWG health guideline of 0.007 ppt.

Arsenic significantly above health guideline

Moderate concern

Arsenic detected at 2.23 ppb, 558x above the EWG health guideline of 0.004 ppb.

Contact KENNEWICK CITY OF

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

General Contact

AddressPO Box 6108, Kennewick, WA 99336

Recommended water filters for Kennewick

Filters matched to the specific contaminants in this water supply.

Reverse Osmosis or NSF P473 certified carbon

$80-$750

Activated carbon and RO are the only technologies proven to remove PFAS at certified levels.

AquaTru Countertop Reverse Osmosis
$449-$599 NSF 42, 53, 58, 401, P473
Editorial pick · affiliate link coming soon
Aquasana OptimH2O Reverse Osmosis + Claryum
$429-$549 NSF 42, 53, 58, 401, P473
Editorial pick · affiliate link coming soon
Waterdrop G3P800 Tankless RO
$600-$750 NSF 58, 372
View on retailer →
Waterdrop N1 Countertop RO
$249-$329 NSF 58, 372
View on retailer →
Clearly Filtered Pitcher Filter
$80-$95 NSF 42, 53, 401, P473
Editorial pick · affiliate link coming soon

Reverse Osmosis

$249-$750

Arsenic is most effectively removed by reverse osmosis. Some specialized adsorptive filters also work.

AquaTru Countertop Reverse Osmosis
$449-$599 NSF 42, 53, 58, 401, P473
Editorial pick · affiliate link coming soon
Aquasana OptimH2O Reverse Osmosis + Claryum
$429-$549 NSF 42, 53, 58, 401, P473
Editorial pick · affiliate link coming soon
Waterdrop G3P800 Tankless RO
$600-$750 NSF 58, 372
View on retailer →
Waterdrop N1 Countertop RO
$249-$329 NSF 58, 372
View on retailer →

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 47/100 breaks down across five weighted components. Read the full methodology →

Health Guideline Performance
10 / 40
Legal Compliance
20 / 20
High-Risk Contaminants
0 / 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
Perfluorooctane sulfonate (PFOS)
PFAS
4.77 ppt 0.3 4.0 100 100 1 EPA violation
Perfluorohexane sulfonate (PFHXS)
PFAS
8.67 ppt 0.001 10.0 8673× over
Total PFOS and PFOA
PFAS
9.64 ppt 0.007 100 100 0.007 1377× over
Arsenic
Heavy metal
2.23 ppb 0.004 10.0 10 10 0.004 558× over
Haloacetic acids (HAA9)
Disinfection byproduct
20.8 ppb 0.06 347× over
Total trihalomethanes (TTHMs)
Disinfection byproduct
34.0 ppb 0.15 80.0 100 226× over
Haloacetic acids (HAA5)
Disinfection byproduct
11.7 ppb 0.1 60.0 60 117× over
Bromodichloromethane
Disinfection byproduct
6.77 ppb 0.06 113× over
Trichloroacetic acid
Disinfection byproduct
6.31 ppb 0.1 63× over
Chloroform
Disinfection byproduct
19.9 ppb 0.4 50× over
Dibromochloromethane
Disinfection byproduct
4.69 ppb 0.1 47× over
Dibromoacetic acid
Disinfection byproduct
0.859 ppb 0.03 29× over
Dichloroacetic acid
Disinfection byproduct
3.52 ppb 0.2 18× over
Chromium (hexavalent)
Heavy metal
0.342 ppb 0.02 17× over
Nitrate
Inorganic
1.83 ppm 0.14 10.0 11.3 11.3 10 13× over
Perfluorooctanoic acid (PFOA)
PFAS
1.04 ppt 0.09 4.0 100 100 0.007 12× over
Nitrate and nitrite
Inorganic
1.58 ppm 0.14 10.0 11.3 11.3 10 11× over
Bromoform
Disinfection byproduct
1.55 ppb 0.5 3.1× over
Chlorate
Disinfection byproduct
210.4 ppb 210.0 1.0× over
Perfluoropentane sulfonic acid (PFPeS)
PFAS
0.21 ppt 1.0 Below guideline
Vanadium
Other
3.55 ppb 21.0 Below guideline
Manganese
Heavy metal
9.75 ppb 100.0 50 80 Below guideline
Barium
Heavy metal
42.8 ppb 700.0 2000.0 1300 2000 Below guideline
Molybdenum
Other
0.764 ppb 40.0 Below guideline
Perfluoropentanoic Acid (PFPeA)
PFAS
4.05 ppt 1000.0 Below guideline
Perfluorohexanoic Acid (PFHxA)
PFAS
3.66 ppt 1000.0 Below guideline
Perfluorobutane sulfonate (PFBS)
PFAS
3.12 ppt 2000.0 Below guideline
Monochloroacetic acid
Disinfection byproduct
0.0665 ppb 53.0 Below guideline
Perfluorobutanoic Acid (PFBA)
PFAS
1.18 ppt 1000.0 Below guideline
Perfluoroheptanoic acid (PFHPA)
PFAS
0.451 ppt 1000.0 Below guideline
Strontium
Radiological
0.176 ppb 1500.0 Below guideline
Fluoride
Inorganic
0.242 ppm 4.0 1.5 1.5 Below guideline
Lithium
Other
1.17 ppb Below guideline
PFOS + PFOA + PFHxS + PFNA
PFAS
18.2 ppt 100 100 0.007 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.

KENNEWICK CITY OF service area

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

About this water system

Public Water System ID
WA5338100
Owner type
Local government
Source water
Surface water
Service connections
39,118
Service area
Kennewick, Benton County, Washington