Short answer: In the 2022–2025 records we hold for San Francisco, no listed result is above a legal limit. Also worth knowing: the water is moderately hard. 1 substance was detected and 31 were tested and not detected. The water is from San Francisco Public Utilities Commission, serving 848,019 residents.
Your water bill or annual water quality report names your actual supplier.
Surface water
The treatment details are not on record.
Mains, then your building’s service line.
Plumbing inside the building is outside this record.
No measured result is above a legal limit; the water is moderately hard.
3.6 gpg, sampled 2025. Utility CCR.
Aesthetic, no federal health limit.
62 mg/L as CaCO3 (3.6 grains/gal), moderately hard. Aesthetic (scale/appliances), not a health finding.
Shows up as scale in kettles, water heaters and fixtures.
Test your own tap first. Technologies that can reduce it: Ion-exchange water softener, Salt-free conditioner, Reverse osmosis (point-of-use).
SFPUC CITY DISTRIBUTION DIVISION (EPA PWSID CA3810011) delivers surface water to 848,019 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 moderately hard water.
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
Safe Home (EnviroTestKits)
Lead, read as one of three ranges: 0–4, 5–15 or 15+ ppb
What it can't tell you: It shows a lead range, not an exact level, and tests nothing else unless you pay extra for the optional lab test.
When your results arrive, read them here → · Compare every kit we list
| Finding | Reference type | Technology | Certification to check |
|---|---|---|---|
| Water hardness3.6 gpg | Aesthetic, no health limit | Ion-exchange water softener, Salt-free conditioner, Reverse osmosis (point-of-use) | Check the certifier’s listing |
| Galvanized service lines653 galvanized on record (EPA inventory, 2026Q2) | Not a tap measurement | Lead-certified carbon filter, or reverse osmosis | NSF/ANSI 53 (lead) |
★ Best choice: Brita Elite Water Filter Pitcher, certified for lead.
| Pick | Product | Details and price | Certification | Why it’s listed | Link |
|---|---|---|---|---|---|
| ★ Best choice | PitcherBrita Elite Water Filter Pitcher | TreatsleadPrice$ | Certified for Lead (NSF/ANSI 53, WQA) | Why it’s listed: its current certification names lead; San Francisco’s record lists galvanized service lines.See the evidence | Check price on Amazon |
| Also good | Under-sinkAquasana Claryum 3-Stage Max Flow Under-Sink Filter (AQ-6300M) | TreatsleadPrice$$ | Certified for Lead (NSF/ANSI 53, WQA) | Why it’s listed: its current certification names lead; San Francisco’s record lists galvanized service lines.See the evidence | Check price at Aquasana |
| Also good | CountertopAquasana Clean Water Machine Countertop Filter (AQ-CWM2) | TreatsleadPrice$$ | Certified for Lead (NSF/ANSI 53, WQA) | Why it’s listed: its current certification names lead; San Francisco’s record lists galvanized service lines.See the evidence | Check price at Aquasana |
| Pick | Product | Details and price | Certification | Why it’s listed | Link |
|---|---|---|---|---|---|
| Also good | Reverse osmosisSmartFlow® Reverse Osmosis | TreatsleadTechnologyReverse osmosisPrice$$$ | Certified for lead (WQA) | Why it’s listed: its current certification names lead; San Francisco’s record lists galvanized service lines.See the evidence | Check price at Aquasana |
| Also good | Under-sinkWaterdrop G3P600 Tankless Reverse-Osmosis System | TreatsleadPrice$$$ | Certified for Lead (NSF/ANSI 58-2024, IAPMO) | Why it’s listed: its current certification names lead; San Francisco’s record lists galvanized service lines.See the evidence | Check price at Waterdrop |
| Also good | Under-sinkWaterdrop G3P800 Tankless Reverse-Osmosis System | TreatsleadPrice$$$ | Certified for Lead (NSF/ANSI 58-2024, IAPMO) | Why it’s listed: its current certification names lead; San Francisco’s record lists galvanized service lines.See the evidence | Check price at Waterdrop |
| Also good | CountertopAquaTru Carafe Countertop Reverse-Osmosis Purifier (AT100) | TreatsleadPrice$$$ | Certified for Lead (NSF/ANSI 58, IAPMO) | Why it’s listed: its current certification names lead; San Francisco’s record lists galvanized service lines.See the evidence | Check price on Amazon |
| Also good | CountertopAquaTru Classic Countertop Reverse-Osmosis Purifier (AT2000) | TreatsleadPrice$$$ | Certified for Lead (NSF/ANSI 58, IAPMO) | Why it’s listed: its current certification names lead; San Francisco’s record lists galvanized service lines.See the evidence | Check price on Amazon |
| Also good | Under-sinkAquasana Claryum 2-Stage Under-Sink Filter (AQ-5200) | TreatsleadPrice$$ | Certified for Lead (NSF/ANSI 53, WQA) | Why it’s listed: its current certification names lead; San Francisco’s record lists galvanized service lines.See the evidence | Check price on Amazon |
| Also good | PitcherCulligan ZeroWater 10-Cup Pitcher (ZEROP10) | TreatsleadPrice$ | Certified for Lead (NSF/ANSI 53, IAPMO) | Why it’s listed: its current certification names lead; San Francisco’s record lists galvanized service lines.See the evidence | Check price on Amazon |
| Also good | Under-sinkFrizzlife SP99 Under-Sink Filter | TreatsleadPrice$$ | Certified for Lead (NSF/ANSI 53-2024, IAPMO) | Why it’s listed: its current certification names lead; San Francisco’s record lists galvanized service lines.See the evidence | Check price on Amazon |
| Also good | Faucet-mountPUR Plus Faucet Filter (FM2500V) | TreatsleadPrice$ | Certified for Lead (NSF/ANSI 53, IAPMO) | Why it’s listed: its current certification names lead; San Francisco’s record lists galvanized service lines.See the evidence | Check price on Amazon |
| Also good | CountertopPatriot Pure Ultimate Water Filtration System | TreatsleadPrice$$ | Certified for Lead (NSF/ANSI 53, NSF, IAPMO) | Why it’s listed: its current certification names lead; San Francisco’s record lists galvanized service lines.See the evidence | Check price on Amazon |
| Also good | Reverse osmosisiSpring RCC7AK Alkaline Reverse Osmosis SystemUse code REFISPRING at checkout: 10% off your first iSpring order. | TechnologyReverse osmosisPrice$$ | Brand lab-tested, not independently certified for lead | See the evidence | Check price at iSpring |
| Also good | Reverse osmosisiSpring RO5004F Tankless Reverse Osmosis System with UVUse code REFISPRING at checkout: 10% off your first iSpring order. | TechnologyReverse osmosisPrice$$$ | Brand lab-tested, not independently certified for lead | See the evidence | Check price at iSpring |
| Also good | Reverse osmosisWaterdrop X12 Reverse Osmosis System | TechnologyReverse osmosisPrice$$$$ | Brand lab-tested, not independently certified for lead | See the evidence | Check price at Waterdrop |
★ Best available: iSpring WGB32B-PFKS PFAS & Heavy Metals Whole House Filter, the best fit here; nothing in this group is certified yet.
| Pick | Product | Details and price | Certification | Why it’s listed | Link |
|---|---|---|---|---|---|
| ★ Best available | Whole-houseiSpring WGB32B-PFKS PFAS & Heavy Metals Whole House FilterUse code REFISPRING at checkout: 10% off your first iSpring order. | Price$$$ | Brand lab-tested, not independently certified for lead | See the evidence | Check price at iSpring |
PurityMap earns a commission from these links. "Best choice" and "Budget pick" go to certified products first; commission never decides them. As an Amazon Associate, PurityMap earns from qualifying purchases. Affiliate disclosure.
Lead service lines
San Francisco Public Utilities Commission reported 653 galvanized service lines to replace in EPA’s inventory (2026Q2). Many utilities replace these lines for free or share the cost. Ask San Francisco Public Utilities Commission whether your home’s line is on its list before you pay anyone.
Local help
Call to be connected with a local plumbing provider about lead service lines, repiping or fixture replacement.
Older buildings may have lead service lines, solder or fixtures. San Francisco’s utility reported 653 galvanized service lines in EPA’s inventory. Test first-draw water, then filter if needed.
None of the 29 PFAS tested was detected in San Francisco’s record. If PFAS matters to you, a filter certification names each compound it covers.
Most utilities keep chlorine or chloramine in the pipes. A carbon filter certified for taste and odor reduces either; your utility can tell you which it uses.
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 Francisco’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 Francisco, no regulated PFAS were detected in EPA's 2024 testing. SFPUC CITY DISTRIBUTION DIVISION (PWSID CA3810011) 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 →
SFPUC CITY DISTRIBUTION DIVISION (PWS ID CA3810011) is the public water system on record for San Francisco, California, serving about 848,019 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 (2023-03-22 to 2024-03-05) was detected. "Not detected" means below the lab's reporting limit, not proven zero. What we found →
Lead is not in San Francisco'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 Francisco holds 32 findings: 1 detected within the reference and 31 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 Francisco's water is recorded as 3.6 gpg, moderately hard. Hardness is an aesthetic and plumbing characteristic, not a health-based limit. Choose your situation →
| Contaminant | Measured | Reference | Sampled | Source |
|---|---|---|---|---|
| Water hardness | 3.6 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 | 2023–2024 | 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 | 2023–2024 | 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 | 2023–2024 | 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 | 2023–2024 | 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 | 2023–2024 | 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 | 2023–2024 | 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) | 2023–2024 | EPA UCMR 5 ↗ (opens in a new tab) |
| Lead (90th percentile) | Not detected | 15 µg/L federal action level | 2022–2024 | EPA SDWIS (Lead & Copper Rule) ↗ (opens in a new tab) |
| Lithium | < 9 µg/L (not detected) | 10 µg/L EPA health reference level (screening, not a legal limit) | 2023–2024 | EPA UCMR 5 ↗ (opens in a new tab) |
| N-ethyl perfluorooctanesulfonamidoacetic acid (NEtFOSAA) | < 5 ng/L (not detected) | No federal or state limit; shown for transparency | 2023–2024 | 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 | 2023–2024 | 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 | 2023–2024 | 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 | 2023–2024 | 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 | 2023–2024 | 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 | 2023–2024 | 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) | 2023–2024 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluorobutanoic acid (PFBA) | < 5 ng/L (not detected) | No federal or state limit; shown for transparency | 2023–2024 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluorodecanoic acid (PFDA) | < 3 ng/L (not detected) | No federal or state limit; shown for transparency | 2023–2024 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluorododecanoic acid (PFDoA) | < 3 ng/L (not detected) | No federal or state limit; shown for transparency | 2023–2024 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluoroheptanesulfonic acid (PFHpS) | < 3 ng/L (not detected) | No federal or state limit; shown for transparency | 2023–2024 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluoroheptanoic acid (PFHpA) | < 3 ng/L (not detected) | No federal or state limit; shown for transparency | 2023–2024 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluorohexanesulfonic acid (PFHxS) | < 3 ng/L (not detected) | 10 ng/L federal MCL (2024) | 2023–2024 | 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) | 2023–2024 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluorononanoic acid (PFNA) | < 4 ng/L (not detected) | 10 ng/L federal MCL (2024) | 2023–2024 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluorooctanesulfonic acid (PFOS) | < 4 ng/L (not detected) | 4.0 ng/L federal MCL (2024) | 2023–2024 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluorooctanoic acid (PFOA) | < 4 ng/L (not detected) | 4.0 ng/L federal MCL (2024) | 2023–2024 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluoropentanesulfonic acid (PFPeS) | < 4 ng/L (not detected) | No federal or state limit; shown for transparency | 2023–2024 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluoropentanoic acid (PFPeA) | < 3 ng/L (not detected) | No federal or state limit; shown for transparency | 2023–2024 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluorotetradecanoic acid (PFTA) | < 8 ng/L (not detected) | No federal or state limit; shown for transparency | 2023–2024 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluorotridecanoic acid (PFTrDA) | < 7 ng/L (not detected) | No federal or state limit; shown for transparency | 2023–2024 | EPA UCMR 5 ↗ (opens in a new tab) |
| Perfluoroundecanoic acid (PFUnA) | < 2 ng/L (not detected) | No federal or state limit; shown for transparency | 2023–2024 | EPA UCMR 5 ↗ (opens in a new tab) |
UCMR5 Analytical Results
UCMR5 Analytical Results: SFPUC CITY DISTRIBUTION DIVISION (CA3810011)
US EPA
State SDWIS Compliance Record
Lead & Copper Rule 90th-percentile: SFPUC CITY DISTRIBUTION DIVISION (CA3810011)
US EPA SDWIS
Consumer Confidence Report (CCR)
San Francisco Water System (SFPUC, City of San Francisco) 2025 Consumer Confidence Report (CCR)
San Francisco Water System (SFPUC, City of San Francisco)
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. SFPUC CITY DISTRIBUTION DIVISION · PWSID CA3810011 · Purity Score 100/100 (Excellent) · Confidence: moderate · Assessed at the water-system level
Full methodology →Start with the hot-or-cold tap check. Where San Francisco Public Utilities Commission reported something related, it's shown below.
Lead at San Francisco Public Utilities Commission: not detected (90th percentile, 2022–2024 monitoring period). Lead has no taste, so a taste neither shows nor rules it out.