Water Quality Report · Updated May 12, 2026

BRENTWOOD

Serving 64,513 residents in BRENTWOOD, California .

National rank 49th percentile
California rank 62th percentile
Data confidence Medium
D
64/100
Below Average
ⓘ How did we get this rating?
Quick answer

BRENTWOOD delivers tap water graded D (64/100) by TapWaterSafety.org. The utility serves approximately 64,513 residents in BRENTWOOD, California using surface water (purchased). The most significant water quality concerns are: Haloacetic acids (HAA5) significantly above health guideline; Total trihalomethanes (TTHMs) significantly above health guideline; Chromium (hexavalent) significantly above health guideline; Arsenic detected. For questions, the utility can be reached at 925-516-6025.

Data sources for this grade: utilities.csv EWG Tap Water Database ⓘ How did we get this rating?
64,513
People served
1
City served
30
Contaminants detected
15
Above health guidelines
0
EPA violations (5 yr)

Is BRENTWOOD tap water safe to drink?

BRENTWOOD delivers tap water that earns a grade of D (64/100) from TapWaterSafety.org — a below-average rating, with multiple concerns including haloacetic acids (haa5) significantly above health guideline.

The utility serves 64,513 residents in BRENTWOOD, drawing from surface water (purchased).

Public testing data identifies 15 contaminants in this water above EWG's health-based guidelines, including: Haloacetic acids (HAA5), Total trihalomethanes (TTHMs), Chromium (hexavalent), Haloacetic acids (HAA9), Arsenic, Bromodichloromethane, Dibromochloromethane, Dibromoacetic acid, Nitrate and nitrite, Nitrate, Chloroform, Bromoform, Dichloroacetic acid, Trichloroacetic acid, Uranium. 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 BRENTWOOD.

Haloacetic acids (HAA5) significantly above health guideline

Moderate concern

Haloacetic acids (HAA5) detected at 35.2 ppb, 352x above the EWG health guideline of 0.1 ppb.

Total trihalomethanes (TTHMs) significantly above health guideline

Moderate concern

Total trihalomethanes (TTHMs) detected at 31.6 ppb, 210x above the EWG health guideline of 0.15 ppb.

Chromium (hexavalent) significantly above health guideline

Moderate concern

Chromium (hexavalent) detected at 3.71 ppb, 186x above the EWG health guideline of 0.02 ppb.

Arsenic detected

Moderate concern

Arsenic detected at 0.561 ppb.

Contact BRENTWOOD

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

Recommended water filters for BRENTWOOD

Filters matched to the specific contaminants in this water supply.

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 64/100 breaks down across five weighted components. Read the full methodology →

Health Guideline Performance
10 / 40
Legal Compliance
20 / 20
High-Risk Contaminants
17 / 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 (HAA5)
Disinfection byproduct
35.2 ppb 0.1 60.0 60 352× over
Total trihalomethanes (TTHMs)
Disinfection byproduct
31.6 ppb 0.15 80.0 100 210× over
Chromium (hexavalent)
Heavy metal
3.71 ppb 0.02 186× over
Haloacetic acids (HAA9)
Disinfection byproduct
8.9 ppb 0.06 148× over
Arsenic
Heavy metal
0.561 ppb 0.004 10.0 10 10 0.004 140× over
Bromodichloromethane
Disinfection byproduct
7.99 ppb 0.06 133× over
Dibromochloromethane
Disinfection byproduct
9.36 ppb 0.1 94× over
Dibromoacetic acid
Disinfection byproduct
1.63 ppb 0.03 54× over
Nitrate and nitrite
Inorganic
3.48 ppm 0.14 10.0 11.3 11.3 10 25× over
Nitrate
Inorganic
3.28 ppm 0.14 10.0 11.3 11.3 10 23× over
Chloroform
Disinfection byproduct
7.08 ppb 0.4 18× over
Bromoform
Disinfection byproduct
6.4 ppb 0.5 13× over
Dichloroacetic acid
Disinfection byproduct
2.52 ppb 0.2 13× over
Trichloroacetic acid
Disinfection byproduct
0.814 ppb 0.1 8.1× over
Uranium
Radiological
2.3 pCi/L 0.43 20.0 30 30 0.43 5.3× over
Chlorate
Disinfection byproduct
103.1 ppb 210.0 Below guideline
Vanadium
Other
5.91 ppb 21.0 Below guideline
Selenium
Heavy metal
7.49 ppb 30.0 50.0 20 40 30 Below guideline
Bromochloromethane
Other
0.00528 ppb 0.06 Below guideline
Molybdenum
Other
2.84 ppb 40.0 Below guideline
Perchlorate
Disinfection byproduct
0.0538 ppb 1.0 Below guideline
Manganese
Heavy metal
1.02 ppb 100.0 50 80 Below guideline
Barium
Heavy metal
3.47 ppb 700.0 2000.0 1300 2000 Below guideline
Monobromoacetic acid
Disinfection byproduct
0.0775 ppb 25.0 Below guideline
Monochloroacetic acid
Disinfection byproduct
0.0263 ppb 53.0 Below guideline
Strontium
Radiological
0.681 ppb 1500.0 Below guideline
Chlorodifluoromethane
Other
0.57 ppb Below guideline
Chromium (total)
Heavy metal
1.53 ppb 100.0 Below guideline
Fluoride
Inorganic
0.274 ppm 4.0 1.5 1.5 Below guideline
Lithium
Other
70.3 ppb 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.

BRENTWOOD service area

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

About this water system

Public Water System ID
CA0710004
Owner type
Local government
Source water
Surface water (purchased)
Service connections
21,441
Service area
BRENTWOOD, Contra Costa County, California