Drinking water quality · 2023
· Verified
What's in City of Daly City, CA tap water
122 contaminants were measured in the City of Daly City, CA water system's 2023 annual report. Each is shown below against its federal limit.
- Reporting year
- 2023
- Contaminants measured
- 122
- Over federal limit
- 0
- Approaching the limit
- 0
- Service area
- CA
PFAS — EPA UCMR5 (2023–2025)
1 PFAS compound detected in City of Daly City, CA
The EPA finalized the first-ever federal drinking-water limits for six PFAS compounds in April 2024. These numbers come straight from EPA's UCMR5 lab dataset — every U.S. system serving more than 3,300 people tested every PFAS sample at an entry point to its distribution system. PFAS not listed below were either tested and not detected, or not yet sampled.
Lithium
● Detected (no federal limit)below national p90 (76.59999999999991 mg/L across detecting U.S. systems)
Where your water comes from · EPA SDWIS
City of Daly City, CA's drinking water comes from ground water, drawn from 5 sources.
Source
- JEFFERSON WELL
- WESTLAKE WELL
- WELL 04 - STANDBY
- JUNIPERO SERRA WELL
- + 1 more
Treatment
- WESTLAKE PUMP STATION - BLENDED-TREATED
- CITRUS PUMP STATION - BLENDED - TREATED
Distribution
Also buys water from SAN FRANCISCO REGIONAL WATER SYSTEM, NORTH COAST COUNTY WATER DIST, and 4 more.
Historical readings · EPA Six-Year Review (2012–2019)
2 contaminants historically over EPA limits in City of Daly City, CA
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.
| Contaminant | Worst detection | EPA limit | Years (2012–2019) |
|---|---|---|---|
NITRATE worst: 2014 | 38.4 mg/L 3.8× | 10 mg/L | '12'13'14'15'16'17'18'19 |
HAA5 worst: 2018 | 0.0638 mg/L 1.1× | 0.06 mg/L | '12'13'14'15'16'17'18'19 |
TTHM worst: 2019 | 0.0688 mg/L 86% | 0.08 mg/L | '12'13'14'15'16'17'18'19 |
GROSS BETA worst: 2019 | 1.27 mrem/yr within | 4 mrem/yr | '19 |
ARSENIC worst: 2013 | 0.003 mg/L within below national p90 | 0.01 mg/L | '13'15 |
CHROMIUM worst: 2013 | 0.025 mg/L within 2.5× the national p90 | 0.1 mg/L | '13'15'16'17'18'19 |
DIQUAT worst: 2013 | 0.0022 mg/L within | 0.02 mg/L | '13 |
FLUORIDE worst: 2015 | 0.24 mg/L within | 4 mg/L | '12'13'15'16'17 |
TCAA worst: 2012 | 0.0163 mg/L | — | '12'13'14'15'16'17'18'19 |
DBAA worst: 2013 | 0.0022 mg/L | — | '13'14'15'16'17 |
DCAA worst: 2012 | 0.0213 mg/L | — | '12'13'14'15'16'17'18'19 |
MBAA worst: 2017 | 0.001 mg/L | — | '17 |
MCAA worst: 2016 | 0.004 mg/L | — | '16'17'19 |
BROMODICHLOROMETHANE worst: 2012 | 0.00107 mg/L | — | '12'13'14'15'16'17'18'19 |
BROMOFORM worst: 2012 | 0.00183 mg/L | — | '12'13'14'15'16 |
CHLOROFORM worst: 2012 | 0.0299 mg/L | — | '12'13'14'15'16'17'18'19 |
DIBROMOCHLOROMETHANE worst: 2013 | 0.00296 mg/L | — | '13'14'15'16'17'18'19 |
Physical & aggregate
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Specific ConductanceA measure of how well water conducts electricity, which tracks dissolved mineral content. | 650 UMHO/CMAverageSource water | 1600 UMHO/CMMCL | Within the limit |
| Total Dissolved SolidsTotal dissolved solids — the combined content of all dissolved minerals and salts. | 400 MG/LAverageSource water | 1000 MG/LMCL | Within the limit |
| ColorA measure of visible tint in the water. | Not detected UNITSHighest single sampleSource water | 15 UNITSMCL | None detected |
| OdorA measure of detectable smell in the water. | Not detected TONHighest single sampleSource water | 3 TONMCL | None detected |
| TurbidityA measure of cloudiness from suspended particles in the water. | Not detected NTUHighest single sampleSource water | 5 NTUMCL | None detected |
| AlkalinityA measure of the water's capacity to neutralize acids. | 94.16666666666667 MG/LAverageSource water | None set | Detected — no federal limit |
| HardnessA measure of dissolved calcium and magnesium minerals. | 239 MG/LAverageSource water | None set | Detected — no federal limit |
| pHA measure of how acidic or basic the water is. | 8.15 PHAverageSource water | None set | Detected — no federal limit |
Metals
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Strontium | 1.2375 PCI/LAverageSource water | 8 PCI/LMCL | Within the limit |
| AluminumA common element sometimes used as a treatment coagulant. | Not detected UG/LHighest single sampleSource water | 1000 UG/LMCL | None detected |
| Antimony | Not detected UG/LHighest single sampleSource water | 6 UG/LMCL | None detected |
| BariumA metal from erosion of natural deposits and industrial discharge. | Not detected UG/LHighest single sampleSource water | 1000 UG/LMCL | None detected |
| Beryllium | Not detected UG/LHighest single sampleSource water | 4 UG/LMCL | None detected |
| BoronA naturally occurring element from rock and soil. | Not detected UG/LHighest single sampleSource water | None set | None detected |
| Cadmium | Not detected UG/LHighest single sampleSource water | 5 UG/LMCL | None detected |
| CopperA metal that enters water from corroding household plumbing. | Not detected UG/LHighest single sampleSource water | 1000 UG/LMCL | None detected |
| IronA naturally occurring metal common in groundwater. | Not detected UG/LHighest single sampleSource water | 300 UG/LMCL | None detected |
| LeadA toxic metal that leaches into water from old service lines, solder, and plumbing fixtures. | Not detected UG/LHighest single sampleSource water | None set | None detected |
| ManganeseA naturally occurring metal from soil and rock. | Not detected UG/LHighest single sampleSource water | 50 UG/LMCL | None detected |
| MercuryA toxic metal from erosion of natural deposits and industrial runoff. | Not detected UG/LHighest single sampleSource water | 2 UG/LMCL | None detected |
| NickelA metal from natural deposits and industrial discharge. | Not detected UG/LHighest single sampleSource water | 100 UG/LMCL | None detected |
| SeleniumA trace element from natural deposits and industrial discharge. | Not detected UG/LHighest single sampleSource water | 50 UG/LMCL | None detected |
| Thallium | Not detected UG/LHighest single sampleSource water | 2 UG/LMCL | None detected |
| ZincA naturally occurring metal that can also enter water from corroding pipes. | Not detected UG/LHighest single sampleSource water | 5000 UG/LMCL | None detected |
| CalciumA naturally occurring mineral that contributes to water hardness. | 18.75 MG/LAverageSource water | None set | Detected — no federal limit |
| Chromium, HexavalentHexavalent chromium ('chromium-6') — the more toxic form of chromium. | 9.658974358974358 UG/LAverageSource water | None set | Detected — no federal limit |
| MagnesiumA naturally occurring mineral that contributes to water hardness. | 37 MG/LAverageSource water | None set | Detected — no federal limit |
| SodiumA naturally occurring salt component. | 45 MG/LAverageSource water | None set | Detected — no federal limit |
| Vanadium | 4.1 UG/LAverageSource water | None set | Detected — no federal limit |
Inorganic chemicals
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| ChlorideA naturally occurring salt compound. | 65 MG/LAverageSource water | 500 MG/LMCL | Within the limit |
| SulfateA naturally occurring mineral from rock and soil. | 56 MG/LAverageSource water | 500 MG/LMCL | Within the limit |
| Asbestos | Not detected MFLHighest single sampleSource water | 7 MFLMCL | None detected |
| Cyanide | Not detected UG/LHighest single sampleSource water | 150 UG/LMCL | None detected |
| NitriteA compound from fertilizer runoff, sewage, and erosion of natural deposits. | Not detected MG/LHighest single sampleSource water | 1 MG/LMCL | None detected |
Radionuclides
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Gross AlphaGross alpha particle activity — a combined measure of alpha-emitting radioactive substances. | 1.206 PCI/LAverageSource water | 15 PCI/LMCL | Within the limit |
| Combined RadiumCombined radium-226 and radium-228 — naturally occurring radioactive elements. | Not detected PCI/LHighest single sampleSource water | None set | None detected |
| UraniumA naturally occurring radioactive metal from erosion of natural deposits. | Not detected PCI/LHighest single sampleSource water | 20 PCI/LMCL | None detected |
Disinfection byproducts
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| PerchlorateA chemical used in rocket fuel and fireworks that can also form during disinfection. | Not detected UG/LHighest single sampleSource water | 6 UG/LMCL | None detected |
Other
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Carbofuran | Not detected UG/LHighest single sampleSource water | 18 UG/LMCL | None detected |
| Carbon Tetrachloride | Not detected UG/LHighest single sampleSource water | 0.5 UG/LMCL | None detected |
| Chlordane | Not detected UG/LHighest single sampleSource water | 0.1 UG/LMCL | None detected |
| Chlorobenzene | Not detected UG/LHighest single sampleSource water | 70 UG/LMCL | None detected |
| Cis Dichloroethylene 12 | Not detected UG/LHighest single sampleSource water | 6 UG/LMCL | None detected |
| Deha | Not detected UG/LHighest single sampleSource water | 400 UG/LMCL | None detected |
| Dehp | Not detected UG/LHighest single sampleSource water | 4 UG/LMCL | None detected |
| Dichloroethane 12 | Not detected UG/LHighest single sampleSource water | 0.5 UG/LMCL | None detected |
| Dichloroethylene 11 | Not detected UG/LHighest single sampleSource water | 6 UG/LMCL | None detected |
| Dichloropropane 12 | Not detected UG/LHighest single sampleSource water | 5 UG/LMCL | None detected |
| Dinoseb | Not detected UG/LHighest single sampleSource water | 7 UG/LMCL | None detected |
| Edb | Not detected UG/LHighest single sampleSource water | 0.05 UG/LMCL | None detected |
| Endothall | Not detected UG/LHighest single sampleSource water | 100 UG/LMCL | None detected |
| Endrin | Not detected UG/LHighest single sampleSource water | 2 UG/LMCL | None detected |
| Glyphosate | Not detected UG/LHighest single sampleSource water | 700 UG/LMCL | None detected |
| Heptachlor | Not detected UG/LHighest single sampleSource water | 0.01 UG/LMCL | None detected |
| Heptachlor Epoxide | Not detected UG/LHighest single sampleSource water | 0.01 UG/LMCL | None detected |
| Hexachlorobenzene | Not detected UG/LHighest single sampleSource water | 1 UG/LMCL | None detected |
| Hexachlorocyclopentadiene | Not detected UG/LHighest single sampleSource water | 50 UG/LMCL | None detected |
| Methoxychlor | Not detected UG/LHighest single sampleSource water | 30 UG/LMCL | None detected |
| O Dichlorobenzene | Not detected UG/LHighest single sampleSource water | 600 UG/LMCL | None detected |
| Oxamyl | Not detected UG/LHighest single sampleSource water | 50 UG/LMCL | None detected |
| P Dichlorobenzene | Not detected UG/LHighest single sampleSource water | 5 UG/LMCL | None detected |
| Pcb Total | Not detected UG/LHighest single sampleSource water | 0.5 UG/LMCL | None detected |
| Pce | Not detected UG/LHighest single sampleSource water | 5 UG/LMCL | None detected |
| Pentachlorophenol | Not detected UG/LHighest single sampleSource water | 1 UG/LMCL | None detected |
| Picloram | Not detected UG/LHighest single sampleSource water | 500 UG/LMCL | None detected |
| Styrene | Not detected UG/LHighest single sampleSource water | 100 UG/LMCL | None detected |
| Tce | Not detected UG/LHighest single sampleSource water | 5 UG/LMCL | None detected |
| Toxaphene | Not detected UG/LHighest single sampleSource water | 3 UG/LMCL | None detected |
| Trans Dichloroethylene 12 | Not detected UG/LHighest single sampleSource water | 10 UG/LMCL | None detected |
| Trichlorobenzene 124 | Not detected UG/LHighest single sampleSource water | 5 UG/LMCL | None detected |
| Trichloroethane 111 | Not detected UG/LHighest single sampleSource water | 200 UG/LMCL | None detected |
| Trichloroethane 112 | Not detected UG/LHighest single sampleSource water | 5 UG/LMCL | None detected |
| Twofourd | Not detected UG/LHighest single sampleSource water | 70 UG/LMCL | None detected |
| Vinyl Chloride | Not detected UG/LHighest single sampleSource water | 0.5 UG/LMCL | None detected |
PFAS ("forever chemicals")
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| 11-Chloroeicosafluoro-3-oxaundecane-1-sulfonic acid (11Cl-PF3OUdS)11-chloroeicosafluoro-3-oxaundecane-1-sulfonic acid, a chlorinated PFAS compound. | Not detected NG/LHighest single sampleSource water | None set | None detected |
| 4,8-Dioxa-3H-perfluorononanoic acid (ADONA)ADONA, a newer-generation PFAS replacement compound. | Not detected NG/LHighest single sampleSource water | None set | None detected |
| 4:2 Fluorotelomer sulfonic acid (4:2 FTS)4:2 fluorotelomer sulfonic acid, a PFAS-related compound. | Not detected NG/LHighest single sampleSource water | None set | None detected |
| 6:2 Fluorotelomer sulfonic acid (6:2 FTS)6:2 fluorotelomer sulfonic acid, a PFAS-related compound. | Not detected NG/LHighest single sampleSource water | None set | None detected |
| 8:2 Fluorotelomer sulfonic acid (8:2 FTS)8:2 fluorotelomer sulfonic acid, a PFAS-related compound. | Not detected NG/LHighest single sampleSource water | None set | None detected |
| 9-Chlorohexadecafluoro-3-oxanonane-1-sulfonic acid (9Cl-PF3ONS)9-chlorohexadecafluoro-3-oxanonane-1-sulfonic acid, a chlorinated PFAS compound. | Not detected NG/LHighest single sampleSource water | None set | None detected |
| Hexafluoropropylene oxide dimer acidHFPO-DA ('GenX chemicals'), a newer-generation PFAS replacement compound. | Not detected NG/LHighest single sampleSource water | None set | None detected |
| Perfluoro-3-methoxypropanoic acid (PFMPA)Perfluoro-3-methoxypropanoic acid, a PFAS-related compound. | Not detected NG/LHighest single sampleSource water | None set | None detected |
| Perfluoro-4-methoxybutanoic acid (PFMBA)Perfluoro-4-methoxybutanoic acid, a PFAS-related compound. | Not detected NG/LHighest single sampleSource water | None set | None detected |
| Perfluoro(2-ethoxyethane)sulfonic acid (PFEESA)Perfluoro(2-ethoxyethane)sulfonic acid, a PFAS-related compound. | Not detected NG/LHighest single sampleSource water | None set | None detected |
| Perfluorodecanoic acid (PFDA)Perfluorodecanoic acid, a longer-chain PFAS 'forever chemical.' | Not detected NG/LHighest single sampleSource water | None set | None detected |
| Perfluorododecanoic acid (PFDoA)Perfluorododecanoic acid, a longer-chain PFAS 'forever chemical.' | Not detected NG/LHighest single sampleSource water | None set | None detected |
| Perfluoroheptanesulfonic acid (PFHpS)Perfluoroheptanesulfonic acid, a PFAS 'forever chemical.' | Not detected NG/LHighest single sampleSource water | None set | None detected |
| Perfluoroheptanoic acidPerfluoroheptanoic acid, a PFAS 'forever chemical.' | Not detected NG/LHighest single sampleSource water | None set | None detected |
| Perfluorohexanoic acidPerfluorohexanoic acid, a shorter-chain PFAS 'forever chemical.' | Not detected NG/LHighest single sampleSource water | None set | None detected |
| Perfluorononanoic acidPerfluorononanoic acid, a PFAS 'forever chemical.' | Not detected NG/LHighest single sampleSource water | None set | None detected |
| Perfluoropentanesulfonic acid (PFPeS)Perfluoropentanesulfonic acid, a PFAS 'forever chemical.' | Not detected NG/LHighest single sampleSource water | None set | None detected |
| Perfluoropentanoic acidPerfluoropentanoic acid, a shorter-chain PFAS 'forever chemical.' | Not detected NG/LHighest single sampleSource water | None set | None detected |
| Perfluoroundecanoic acid (PFUnA)Perfluoroundecanoic acid, a longer-chain PFAS 'forever chemical.' | Not detected NG/LHighest single sampleSource water | None set | None detected |
| PFBAPerfluorobutanoic acid, a shorter-chain PFAS 'forever chemical.' | Not detected NG/LHighest single sampleSource water | None set | None detected |
VOCs & pesticides
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| 1,2,3-TCP | Not detected UG/LHighest single sampleSource water | 0.005 UG/LMCL | None detected |
| AtrazineA widely used agricultural herbicide that reaches water through runoff. | Not detected UG/LHighest single sampleSource water | 1 UG/LMCL | None detected |
| Benzene | Not detected UG/LHighest single sampleSource water | 1 UG/LMCL | None detected |
| Benzo(a)pyrene | Not detected UG/LHighest single sampleSource water | 0.2 UG/LMCL | None detected |
| Dalapon | Not detected UG/LHighest single sampleSource water | 200 UG/LMCL | None detected |
| Dichloromethane | Not detected UG/LHighest single sampleSource water | 5 UG/LMCL | None detected |
| Ethylbenzene | Not detected UG/LHighest single sampleSource water | 300 UG/LMCL | None detected |
| Simazine | Not detected UG/LHighest single sampleSource water | 4 UG/LMCL | None detected |
| Toluene | Not detected UG/LHighest single sampleSource water | 150 UG/LMCL | None detected |
| XylenesA group of industrial solvents found in gasoline and paint. | Not detected UG/LHighest single sampleSource water | 1750 UG/LMCL | None detected |
People also ask about City of Daly City, CA's water
+Is City of Daly City, CA tap water safe to drink in 2023?
Every one of the 122 contaminants measured in City of Daly City, CA's 2023 Consumer Confidence Report is below its federal limit. "Safe" under the EPA's drinking-water standards is health-based, not aesthetic — but by those standards, no measured contaminant in this report exceeds its enforceable threshold. Individual health concerns (e.g. immunocompromised, infant, pregnancy) may warrant additional filtering regardless of compliance.
+What contaminants are in City of Daly City, CA tap water?
122 contaminants were measured in City of Daly City, CA's 2023 Consumer Confidence Report, spanning other, metals, and pfas ("forever chemicals"). 81 have an enforceable federal limit; the rest are detected but unregulated. Every measured value, in the utility's own units, is on this page.
+Where does the data on this page come from?
Every value is transcribed from City of Daly City, 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 Daly City, 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.