Drinking water quality · 2023

· Verified

What's in City of Antioch, CA tap water

99 contaminants were measured in the City of Antioch, CA water system's 2023 annual report. Each is shown below against its federal limit 5 sit at or above that limit.

Reporting year
2023
Contaminants measured
99
Over federal limit
5
Approaching the limit
0
Worst contaminant
Iron
3.7× the limit
Service area
CA
state-level CCR
Source
Utility CCR

Where your water comes from · EPA SDWIS

City of Antioch, CA's drinking water comes from surface water, drawn from 2 sources.

Source

2surface water
  • ANTIOCH MUNICIPAL RESERVOIR
  • SAN JOAQUIN RIVER INTAKE

Treatment

1treatment plant
  • ANTIOCH WTP

Distribution

0storage units

Also buys water from CONTRA COSTA WATER DISTRICT, RANDALL-BOLD WATER TREATMENT PLANT, and 2 more.

Historical readings · EPA Six-Year Review (2012–2019)

1 contaminant historically over EPA limits in City of Antioch, CA

About this data

Every U.S. public water system reports compliance-monitoring data to EPA. The Six-Year Review releases the 2012–2019 window as a single dataset — here's what your system reported, year by year. Values shown are the highest detection per analyte per year, compared to the federal MCL.

ContaminantWorst detectionEPA limitYears (2012–2019)
BROMATE
worst: 2014
0.01 mg/L
1.0×
0.01 mg/L
'13'14'17
TTHM
worst: 2018
0.074 mg/L
93%
0.08 mg/L
'12'13'14'16'17'18'19
DICHLOROMETHANE
worst: 2017
0.0034 mg/L
within
0.005 mg/L
'17
ARSENIC
worst: 2013
0.0047 mg/L
within
below national p90
0.01 mg/L
'12'13'14'15'16'17'18'19
CADMIUM
worst: 2017
0.0016 mg/L
within
near national p90
0.005 mg/L
'17
FLUORIDE
worst: 2012
0.95 mg/L
within
4 mg/L
'12'13'14'15'16'17'18'19
HAA5
worst: 2017
0.0088 mg/L
within
0.06 mg/L
'12'13'14'16'17
NITRATE
worst: 2013
0.994 mg/L
within
10 mg/L
'12'13'14'15'16'17'18'19
BARIUM
worst: 2012
0.16 mg/L
within
near national p90
2 mg/L
'12'16'17'18'19
NITRATE NITRITE
worst: 2017
0.72 mg/L
within
10 mg/L
'16'17'18'19
DEHP
worst: 2019
0.00028 mg/L
within
0.006 mg/L
'19
CYANIDE
worst: 2018
0.0011 mg/L
within
below national p90
0.2 mg/L
'18'19
DEHA
worst: 2019
0.00021 mg/L
within
0.4 mg/L
'19
COPPER
worst: 2019
0.32 mg/L
below national p90
'19
LEAD
worst: 2019
0.0028 mg/L
'19
DBAA
worst: 2012
0.0029 mg/L
'12'13'14'16'17
DCAA
worst: 2012
0.0026 mg/L
'12'13'14'16'17
MBAA
worst: 2016
0.0026 mg/L
'16
TCAA
worst: 2017
0.0042 mg/L
'17
BROMODICHLOROMETHANE
worst: 2012
0.0053 mg/L
'12'13'14'16'17'18'19
BROMOFORM
worst: 2012
0.0076 mg/L
'12'13'14'16'17'18'19
CHLOROFORM
worst: 2012
0.0029 mg/L
'12'13'14'16'17'18'19
DIBROMOCHLOROMETHANE
worst: 2012
0.0079 mg/L
'12'13'14'16'17'18'19
PWSID CA0710001 · Source: EPA Six-Year Review 4 (2012–2019). Values are the highest detection in each calendar year; non-detect years are omitted. Year tags above show every year with a detection.

Metals

ContaminantMeasuredStatus
IronA naturally occurring metal common in groundwater.1100 UG/LAverageOtherAt or above the limit
ManganeseA naturally occurring metal from soil and rock.52 UG/LAverageOtherAt or above the limit
AluminumA common element sometimes used as a treatment coagulant.790 UG/LAverageOtherWithin the limit
ZincA naturally occurring metal that can also enter water from corroding pipes.87 UG/LAverageSource waterWithin the limit
AntimonyNot detected UG/LHighest single sampleEntry pointNone detected
BerylliumNot detected UG/LHighest single sampleEntry pointNone detected
MercuryA toxic metal from erosion of natural deposits and industrial runoff.Not detected UG/LHighest single sampleSource waterNone detected
NickelA metal from natural deposits and industrial discharge.Not detected UG/LHighest single sampleOtherNone detected
SeleniumA trace element from natural deposits and industrial discharge.Not detected UG/LHighest single sampleEntry pointNone detected
ThalliumNot detected UG/LHighest single sampleEntry pointNone detected
CalciumA naturally occurring mineral that contributes to water hardness.9 MG/LAverageOtherDetected — no federal limit
Chromium, HexavalentHexavalent chromium ('chromium-6') — the more toxic form of chromium.0.052 UG/LAverageEntry pointDetected — no federal limit
MagnesiumA naturally occurring mineral that contributes to water hardness.6.3 MG/LAverageOtherDetected — no federal limit
PotassiumA naturally occurring mineral from rock and soil.2 MG/LAverageOtherDetected — no federal limit
SodiumA naturally occurring salt component.30.666666666666668 MG/LAverageEntry pointDetected — no federal limit

Physical & aggregate

ContaminantMeasuredStatus
TurbidityA measure of cloudiness from suspended particles in the water.18 NTUAverageOtherAt or above the limit
ColorA measure of visible tint in the water.35 UNITSAverageOtherAt or above the limit
OdorA measure of detectable smell in the water.3 TONAverageEntry pointAt or above the limit
Specific ConductanceA measure of how well water conducts electricity, which tracks dissolved mineral content.276.6666666666667 UMHO/CMAverageEntry pointWithin the limit
Total Dissolved SolidsTotal dissolved solids — the combined content of all dissolved minerals and salts.162.66666666666666 MG/LAverageEntry pointWithin the limit
AlkalinityA measure of the water's capacity to neutralize acids.39.22222222222222 MG/LAverageEntry pointDetected — no federal limit
HardnessA measure of dissolved calcium and magnesium minerals.58 MG/LAverageOtherDetected — no federal limit
pHA measure of how acidic or basic the water is.8.066666666666666 PHAverageEntry pointDetected — no federal limit

Inorganic chemicals

ContaminantMeasuredStatus
ChlorideA naturally occurring salt compound.34.5 MG/LAverageOtherWithin the limit
SulfateA naturally occurring mineral from rock and soil.26.933333333333334 MG/LAverageEntry pointWithin the limit
AmmoniaNot detected MG/LHighest single sampleOtherNone detected
NitriteA compound from fertilizer runoff, sewage, and erosion of natural deposits.Not detected MG/LHighest single sampleEntry pointNone detected
BromideA naturally occurring salt found in source water.0.1 MG/LAverageOtherDetected — no federal limit

Disinfection byproducts

ContaminantMeasuredStatus
PerchlorateA chemical used in rocket fuel and fireworks that can also form during disinfection.Not detected UG/LHighest single sampleEntry pointNone detected

Other

ContaminantMeasuredStatus
CarbofuranNot detected UG/LHighest single sampleOtherNone detected
Carbon TetrachlorideNot detected UG/LHighest single sampleEntry pointNone detected
ChlordaneNot detected UG/LHighest single sampleOtherNone detected
ChlorobenzeneNot detected UG/LHighest single sampleEntry pointNone detected
ChromiumNot detected UG/LHighest single sampleOtherNone detected
Cis Dichloroethylene 12Not detected UG/LHighest single sampleEntry pointNone detected
Dichloroethane 12Not detected UG/LHighest single sampleOtherNone detected
Dichloroethylene 11Not detected UG/LHighest single sampleOtherNone detected
Dichloropropane 12Not detected UG/LHighest single sampleEntry pointNone detected
DinosebNot detected UG/LHighest single sampleOtherNone detected
DiquatNot detected UG/LHighest single sampleOtherNone detected
EdbNot detected UG/LHighest single sampleOtherNone detected
EndothallNot detected UG/LHighest single sampleOtherNone detected
EndrinNot detected UG/LHighest single sampleOtherNone detected
GlyphosateNot detected UG/LHighest single sampleOtherNone detected
HeptachlorNot detected UG/LHighest single sampleOtherNone detected
Heptachlor EpoxideNot detected UG/LHighest single sampleOtherNone detected
HexachlorobenzeneNot detected UG/LHighest single sampleOtherNone detected
HexachlorocyclopentadieneNot detected UG/LHighest single sampleOtherNone detected
McaaNot detected UG/LHighest single sampleDistributionNone detected
MethoxychlorNot detected UG/LHighest single sampleOtherNone detected
O DichlorobenzeneNot detected UG/LHighest single sampleSource waterNone detected
OxamylNot detected UG/LHighest single sampleOtherNone detected
P DichlorobenzeneNot detected UG/LHighest single sampleEntry pointNone detected
Pcb TotalNot detected UG/LHighest single sampleOtherNone detected
PceNot detected UG/LHighest single sampleOtherNone detected
PentachlorophenolNot detected UG/LHighest single sampleOtherNone detected
PicloramNot detected UG/LHighest single sampleOtherNone detected
StyreneNot detected UG/LHighest single sampleOtherNone detected
TceNot detected UG/LHighest single sampleSource waterNone detected
ToxapheneNot detected UG/LHighest single sampleOtherNone detected
Trans Dichloroethylene 12Not detected UG/LHighest single sampleSource waterNone detected
Trichlorobenzene 124Not detected UG/LHighest single sampleEntry pointNone detected
Trichloroethane 111Not detected UG/LHighest single sampleOtherNone detected
Trichloroethane 112Not detected UG/LHighest single sampleOtherNone detected
TwofourdNot detected UG/LHighest single sampleOtherNone detected
Vinyl ChlorideNot detected UG/LHighest single sampleEntry pointNone detected

VOCs & pesticides

ContaminantMeasuredStatus
AtrazineA widely used agricultural herbicide that reaches water through runoff.Not detected UG/LHighest single sampleOtherNone detected
BenzeneNot detected UG/LHighest single sampleSource waterNone detected
Benzo(a)pyreneNot detected UG/LHighest single sampleOtherNone detected
ChloroethaneA volatile organic compound used in some industrial processes.Not detected UG/LHighest single sampleSource waterNone detected
ChloromethaneNot detected UG/LHighest single sampleEntry pointNone detected
DalaponNot detected UG/LHighest single sampleOtherNone detected
DichlorodifluoromethaneNot detected UG/LHighest single sampleSource waterNone detected
EthylbenzeneNot detected UG/LHighest single sampleEntry pointNone detected
SimazineNot detected UG/LHighest single sampleOtherNone detected
TolueneNot detected UG/LHighest single sampleSource waterNone detected
XylenesA group of industrial solvents found in gasoline and paint.Not detected UG/LHighest single sampleEntry pointNone detected
Source: City of Antioch, CA's 2023 Consumer Confidence Report — the annual drinking-water report every U.S. utility is required to publish. The numbers on this page are the utility's own. A water-quality report covers an entire service area, not a single address.

People also ask about City of Antioch, CA's water

+Is City of Antioch, CA tap water safe to drink in 2023?

The 2023 Consumer Confidence Report for the City of Antioch, CA water utility lists 5 contaminants at or above the federal limit: Iron, Turbidity, Color, Manganese, and Odor. Whether that means the water is "unsafe" depends on which contaminant, how long the exposure, and individual health factors. The table on this page shows the measured value, the federal threshold, and the regulated statistic used for compliance.

+What contaminants are in City of Antioch, CA tap water?

99 contaminants were measured in City of Antioch, CA's 2023 Consumer Confidence Report, spanning other, metals, and vocs & pesticides. 76 have an enforceable federal limit; the rest are detected but unregulated. Every measured value, in the utility's own units, is on this page.

+Which contaminants exceed federal limits in City of Antioch, CA tap water?

5 contaminants in City of Antioch, CA's 2023 report sit at or above the federal limit: Iron (3.7× the limit); Turbidity (3.6× the limit); Color (2.3× the limit); Manganese (1.0× the limit); Odor (1.0× the limit). The EPA enforces these limits against the regulated reporting statistic — typically a running annual average or 90th percentile — not a one-off sample spike.

+What is the worst contaminant in City of Antioch, CA tap water?

The contaminant with the highest measured value relative to its federal limit in the 2023 report is Iron, at 3.7× the federal threshold. It belongs to the metals family of contaminants.

+Where does the data on this page come from?

Every value is transcribed from City of Antioch, CA's 2023 Consumer Confidence Report — the annual drinking-water report every U.S. public water utility is required by federal law to publish. The original source document is archived and viewable on this site. A water-quality report covers an entire service area, not a single address.

+How often is City of Antioch, CA's water quality data updated?

Each U.S. public water utility publishes one Consumer Confidence Report per year, covering the prior calendar year's measurements. This page reflects the 2023 report; a new report will replace it once the utility publishes its next annual update.

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