Short answer: In the 2023–2026 records we hold for San Diego, no listed result is above a legal limit. Also worth knowing: lithium sits above a screening level, and the water is very hard. 2 substances were detected and 30 were tested and not detected. The water is from City of San Diego, serving 1,408,937 residents.
EPA lists this system for the city. Your water bill or annual water quality report names your actual supplier. Source: EPA SDWIS 2026Q2.
Surface water
Treated and disinfected with chloramine.
Mains, then your building’s service line.
Plumbing inside the building is outside this record.
No measured result is above a legal limit; lithium sits above a screening level, and the water is very hard.
65 µg/L, sampled 2023-01-25 to 2023-10-18. EPA UCMR 5.
10 µg/L EPA health reference level (screening, not a legal limit).
Detected at up to 65 µg/L (above the 10 µg/L EPA health reference level; a screening level, not a legal limit).
Where it enters is not in this record.
Test your own tap first. To reduce it: Depends on the contaminant (The certifier's listing for each named contaminant).
12.9 gpg, sampled 2025. Utility CCR.
Aesthetic, no federal health limit.
220 mg/L as CaCO3 (12.9 grains/gal), very hard. Aesthetic (scale/appliances), not a health finding.
Shows up as scale in kettles, water heaters and fixtures.
Test your own tap first. To reduce it: Ion-exchange water softener (NSF/ANSI 44 (softeners)).
SAN DIEGO, CITY OF (EPA PWSID CA3710020) delivers surface water to 1,408,937 residents. This report reflects 29 individual PFAS result(s) from the source UCMR5 observations and the latest Lead & Copper Rule 90th-percentile result. The utility's 2025 CCR reports very hard water and chloramine disinfection.
0health-based violations in the last 10 years
From EPA SDWIS. A clean violation history means no enforcement action was recorded; it does not cover contaminants without a limit.
No result is not a pass. Your utility's annual water quality report may list them, and a certified lab test covers your own tap.
The record describes water leaving treatment and samples across the system. Pipes, solder and fixtures inside a building can add lead the record can’t see, especially in older buildings with lead service lines.
Test your waterMeasured in this report
Sampled across the system
Not in this record
Only a tap test measures it
Know what comes from your tap, starting with a first-draw lead sample.
Compare each result with its named reference in our test reader.
Choose a technology certified for what your test found.
Screening tells you if something is worth a closer look; a lab result is the number you can act on.
As an Amazon Associate, PurityMap earns from qualifying purchases. Affiliate disclosure.
Lab-certified results
ETR Laboratories
50+ substances, including lead, copper, arsenic, nitrate, hardness and coliform bacteria
What it can't tell you: It does not test PFAS, and not every result on the panel falls under the lab's accredited scope.
Screening: quick check, not lab-grade
Silver Lake Research
Lead, bacteria, nitrate, copper, iron, chlorine, hardness and pH
What it can't tell you: Each test gives a yes/no or a rough range, not a lab number, and it cannot detect PFAS or arsenic.
When your results arrive, read them here → · Compare every kit we list
| Finding | Reference type | Technology | Certification to check |
|---|---|---|---|
| Lithium65 µg/L | Screening level | Depends on the contaminant | The certifier's listing for each named contaminant |
| Water hardness12.9 gpg | Aesthetic, no health limit | Ion-exchange water softener | NSF/ANSI 44 (softeners) |
Each card names which San Diego findings its current certification covers, and which it doesn't.
As an Amazon Associate, PurityMap earns from qualifying purchases. A product appears here only when a current certification record covers at least one identified concern; every concern stays listed. The retail offer is looked up afterwards and never changes which products appear or their order. Affiliate disclosure.
Local help
A local plumber can look at your home and install a water softener or whole-home system.
Older buildings may have lead service lines, solder or fixtures. Lead is not in San Diego’s published record, so only a tap test tells you. Test first-draw water, then filter if needed.
None of the 29 PFAS tested was detected in San Diego’s record. If PFAS matters to you, a filter certification names each compound it covers.
Utilities keep a disinfectant in the pipes on the way to your tap. A carbon filter certified for chloramine reduces the taste.
Scale is a comfort and appliance issue, not a health one.
Reverse osmosis reduces many dissolved contaminants, including lead and minerals, at a single faucet, with some water sent to drain.
Get one email when San Diego’s record changes.
One email when a new sampling round is published, a result moves above or below its reference, or the system's score changes.PurityMap does not give a safe/unsafe verdict; it shows what the public records measured. For San Diego, no regulated PFAS were detected in EPA's 2024 testing. SAN DIEGO, CITY OF (PWSID CA3710020) has a Purity Score of 100/100 (confidence: moderate), assessed at the water-system level and computed only from contaminants that were measured. Water can change in your own pipes, so a certified test is the only way to know what comes out of your tap. What we found →
SAN DIEGO, CITY OF (PWS ID CA3710020) is the public water system on record for San Diego, California, serving about 1,408,937 people. Confirm the utility on your water bill before acting on a specific finding. Water utility →
Surface water (primary source of record in EPA SDWIS). Water utility →
None of the 29 PFAS in EPA's UCMR 5 testing (2023-01-25 to 2023-10-18) was detected. "Not detected" means below the lab's reporting limit, not proven zero. What we found →
Lead is not in San Diego's current published record. Lead usually enters from a building's own pipes and fixtures, so a certified home test is the way to know yours. Your household →
PurityMap's current record for San Diego holds 32 findings: 2 above a reference and 30 not detected. Each finding links to its dated public record; a parameter that was never monitored is shown as pending, not as a pass. Records →
San Diego's water is recorded as 12.9 gpg, very hard. Hardness is an aesthetic and plumbing characteristic, not a health-based limit. Choose your situation →
| Contaminant | Measured | Reference | Sampled | Source |
|---|---|---|---|---|
| Lithium | 65 µg/L | 10 µg/L EPA health reference level (screening, not a legal limit) | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
| Water hardness | 12.9 gpg | Aesthetic, no federal health limit | 2025 | Utility CCR ↗ (opens in a new tab) |
| 11-Chloroeicosafluoro-3-oxaundecane-1-sulfonic acid (11Cl-PF3OUdS) | < 5 ng/L (not detected) | No federal or state limit; shown for transparency | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
| 1H, 1H, 2H, 2H-perfluorodecane sulfonic acid (8:2 FTS) | < 5 ng/L (not detected) | No federal or state limit; shown for transparency | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
| 1H, 1H, 2H, 2H-perfluorohexane sulfonic acid (4:2 FTS) | < 3 ng/L (not detected) | No federal or state limit; shown for transparency | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
| 1H, 1H, 2H, 2H-perfluorooctane sulfonic acid (6:2 FTS) | < 5 ng/L (not detected) | No federal or state limit; shown for transparency | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
| 4,8-Dioxa-3H-perfluorononanoic acid (ADONA) | < 3 ng/L (not detected) | No federal or state limit; shown for transparency | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
| 9-Chlorohexadecafluoro-3-oxanone-1-sulfonic acid (9Cl-PF3ONS) | < 2 ng/L (not detected) | No federal or state limit; shown for transparency | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
| Hexafluoropropylene oxide dimer acid (HFPO-DA) (GenX chemicals) | < 5 ng/L (not detected) | 10 ng/L federal MCL (2024) | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
| Lead (90th percentile) | Not detected | 15 µg/L federal action level | 2024–2026 | EPA SDWIS (Lead & Copper Rule) ↗ (opens in a new tab) |
| N-ethyl perfluorooctanesulfonamidoacetic acid (NEtFOSAA) | < 5 ng/L (not detected) | No federal or state limit; shown for transparency | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
| N-methyl perfluorooctanesulfonamidoacetic acid (NMeFOSAA) | < 6 ng/L (not detected) | No federal or state limit; shown for transparency | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
| Nonafluoro-3,6-dioxaheptanoic acid (NFDHA) | < 20 ng/L (not detected) | No federal or state limit; shown for transparency | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluoro (2-ethoxyethane) sulfonic acid (PFEESA) | < 3 ng/L (not detected) | No federal or state limit; shown for transparency | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluoro-3-methoxypropanoic acid (PFMPA) | < 4 ng/L (not detected) | No federal or state limit; shown for transparency | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluoro-4-methoxybutanoic acid (PFMBA) | < 3 ng/L (not detected) | No federal or state limit; shown for transparency | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluorobutanesulfonic acid (PFBS) | < 3 ng/L (not detected) | 2,000 ng/L EPA health advisory (screening, not a legal limit) | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluorobutanoic acid (PFBA) | < 5 ng/L (not detected) | No federal or state limit; shown for transparency | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluorodecanoic acid (PFDA) | < 3 ng/L (not detected) | No federal or state limit; shown for transparency | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluorododecanoic acid (PFDoA) | < 3 ng/L (not detected) | No federal or state limit; shown for transparency | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluoroheptanesulfonic acid (PFHpS) | < 3 ng/L (not detected) | No federal or state limit; shown for transparency | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluoroheptanoic acid (PFHpA) | < 3 ng/L (not detected) | No federal or state limit; shown for transparency | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluorohexanesulfonic acid (PFHxS) | < 3 ng/L (not detected) | 10 ng/L federal MCL (2024) | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluorohexanoic acid (PFHxA) | < 3 ng/L (not detected) | 400,000 ng/L Michigan EGLE state MCL (strictest US state) | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluorononanoic acid (PFNA) | < 4 ng/L (not detected) | 10 ng/L federal MCL (2024) | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluorooctanesulfonic acid (PFOS) | < 4 ng/L (not detected) | 4.0 ng/L federal MCL (2024) | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluorooctanoic acid (PFOA) | < 4 ng/L (not detected) | 4.0 ng/L federal MCL (2024) | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluoropentanesulfonic acid (PFPeS) | < 4 ng/L (not detected) | No federal or state limit; shown for transparency | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluoropentanoic acid (PFPeA) | < 3 ng/L (not detected) | No federal or state limit; shown for transparency | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluorotetradecanoic acid (PFTA) | < 8 ng/L (not detected) | No federal or state limit; shown for transparency | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluorotridecanoic acid (PFTrDA) | < 7 ng/L (not detected) | No federal or state limit; shown for transparency | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluoroundecanoic acid (PFUnA) | < 2 ng/L (not detected) | No federal or state limit; shown for transparency | 2023 | EPA UCMR 5 ↗ (opens in a new tab) |
UCMR5 Analytical Results
UCMR5 Analytical Results: SAN DIEGO, CITY OF (CA3710020)
US EPA
State SDWIS Compliance Record
Lead & Copper Rule 90th-percentile: SAN DIEGO, CITY OF (CA3710020)
US EPA SDWIS
Consumer Confidence Report (CCR)
City of San Diego 2025 Consumer Confidence Report (CCR)
City of San Diego
Methodology: how we analyze water. Prepared with AI assistance and reviewed by the PurityMap Editorial Team before publication.
EPA SDWIS, EPA UCMR 5 and utility reports, each dated and linked.
Units converted to one basis; a non-detect kept distinct from zero.
Each result tagged by reference type: MCL, action level, screening level or aesthetic.
Every value sits against its own reference, never a blended one.
Measured subjects summarised at the water-system level; an open health-based violation caps the score.
Treatment is matched to what was found; a product is called certified only when its current certification names it.
What the Purity Score means: a summary of this water system’s published record, capped while a health-based violation is open. It is not a test of any tap. SAN DIEGO, CITY OF · PWSID CA3710020 · Purity Score 100/100 (Excellent) · Confidence: moderate · Assessed at the water-system level
Full methodology →Start with the hot-or-cold tap check. Where City of San Diego reported something related, it's shown below.
San Diego disinfects with chloramine (utility water-quality report).
Lead at City of San Diego: not detected (90th percentile, 2024–2026 monitoring period (still open)). Lead has no taste, so a taste neither shows nor rules it out.