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Community Water System · PWS CA3810001

San Francisco Regional Water System

Operator location Burlingame, California - 63% of 16 violations are health-based (upper-third health share (> 23%)); surface water source; 600 served per SDWIS.

600
People served (this PWS)
16
EPA violations (this PWS)
10
Health-based (this PWS)
No PFAS
UCMR5 (this PWS)
Follow published updates (RSS)

San Francisco Regional Water System standing, low SDWIS violation third

63% of 16 recorded violations are health-based - upper-third health share (> 23%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 63% is upper-third health share (> 23%). UCMR5: UCMR5 tested, none detected. Population rank #26,155 of 29,740 among systems serving 500+.

The verdict

San Francisco Regional Water System is in the lower third by violation count (16; lower-third violation load (≤ 21 violations)). A low count does not mean the system is unmonitored - monitoring and reporting violations still appear in SDWIS. Population served is smaller (600; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 63% - most of this ledger is MCL or treatment-technique exceedance. UCMR5 tested this system and reported no PFAS above the minimum reporting level.

#26,155 of 29,740
Population · /systems
#1,505 of 1,701
Population · CA
16
Total EPA violations on record
63%
Health-based (MCL / treatment failure)

Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.

System Details

System Type
Community
Owner Type
Local
Connections
256
County
San Francisco
School/Daycare
No
MCL Violations
2
Monitoring Violations
4
Treatment Tech Violations
8

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Surface Water Treatment Rule TT 8 1998
Coliform (TCR) MR 2 1992
Antimony, Total MR 2 1996
Coliform (TCR) MCL 2 1991

Violation Count vs. the National Corpus

San Francisco Regional Water System has 16 recorded EPA violations, 26% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 72% carry more. 63% of this system's own violations are health-based (10 of 16), and it ranks #26,155 of 29,740 by population served among that same cohort.

EPA violations vs. the national water-system corpus

Public water systems serving 500+ people (EPA SDWIS)

16 Lower than most fewer violations than 72% of 29,740 water systems

the national water-system corpus, bucketed by value

Each bar is a band; taller bars hold more water systems. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.

Source EPA SDWIS · 2026-05-15

PFAS Testing Results (UCMR5)

Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 0 of 298 samples detected PFAS.

Contaminant Date Result MRL Status
PFUnA 9/19/2023 <2.00 ppt 2.00 ppt Not Detected
11Cl-PF3OUdS 9/19/2023 <5.00 ppt 5.00 ppt Not Detected
9Cl-PF3ONS 9/19/2023 <2.00 ppt 2.00 ppt Not Detected
ADONA 9/19/2023 <3.00 ppt 3.00 ppt Not Detected
HFPO-DA 9/19/2023 <5.00 ppt 5.00 ppt Not Detected
PFBA 9/19/2023 <5.00 ppt 5.00 ppt Not Detected
6:2 FTS 9/19/2023 <5.00 ppt 5.00 ppt Not Detected
4:2 FTS 9/19/2023 <3.00 ppt 3.00 ppt Not Detected
PFTA 9/19/2023 <8.00 ppt 8.00 ppt Not Detected
PFHpS 9/19/2023 <3.00 ppt 3.00 ppt Not Detected
PFMPA 9/19/2023 <4.00 ppt 4.00 ppt Not Detected
PFPeA 9/19/2023 <3.00 ppt 3.00 ppt Not Detected
PFMBA 9/19/2023 <3.00 ppt 3.00 ppt Not Detected
PFEESA 9/19/2023 <3.00 ppt 3.00 ppt Not Detected
NFDHA 9/19/2023 <20.00 ppt 20.00 ppt Not Detected
PFPeS 9/19/2023 <4.00 ppt 4.00 ppt Not Detected
8:2 FTS 9/19/2023 <5.00 ppt 5.00 ppt Not Detected
PFBS 9/19/2023 <3.00 ppt 3.00 ppt Not Detected
NMeFOSAA 9/19/2023 <6.00 ppt 6.00 ppt Not Detected
PFTrDA 9/19/2023 <7.00 ppt 7.00 ppt Not Detected
NEtFOSAA 9/19/2023 <5.00 ppt 5.00 ppt Not Detected
PFHxA 9/19/2023 <3.00 ppt 3.00 ppt Not Detected
PFHpA 9/19/2023 <3.00 ppt 3.00 ppt Not Detected
PFHxS 9/19/2023 <3.00 ppt 3.00 ppt Not Detected
PFNA 9/19/2023 <4.00 ppt 4.00 ppt Not Detected
PFOS 9/19/2023 <4.00 ppt 4.00 ppt Not Detected
PFOA 9/19/2023 <4.00 ppt 4.00 ppt Not Detected
PFDA 9/19/2023 <3.00 ppt 3.00 ppt Not Detected
PFDoA 9/19/2023 <3.00 ppt 3.00 ppt Not Detected
ADONA 9/12/2023 <3.00 ppt 3.00 ppt Not Detected
9Cl-PF3ONS 9/12/2023 <2.00 ppt 2.00 ppt Not Detected
11Cl-PF3OUdS 9/12/2023 <5.00 ppt 5.00 ppt Not Detected
PFUnA 9/12/2023 <2.00 ppt 2.00 ppt Not Detected
PFHxA 9/12/2023 <3.00 ppt 3.00 ppt Not Detected
HFPO-DA 9/12/2023 <5.00 ppt 5.00 ppt Not Detected
PFMBA 9/12/2023 <3.00 ppt 3.00 ppt Not Detected
PFBA 9/12/2023 <5.00 ppt 5.00 ppt Not Detected
4:2 FTS 9/12/2023 <3.00 ppt 3.00 ppt Not Detected
PFPeA 9/12/2023 <3.00 ppt 3.00 ppt Not Detected
6:2 FTS 9/12/2023 <5.00 ppt 5.00 ppt Not Detected
PFEESA 9/12/2023 <3.00 ppt 3.00 ppt Not Detected
NFDHA 9/12/2023 <20.00 ppt 20.00 ppt Not Detected
PFPeS 9/12/2023 <4.00 ppt 4.00 ppt Not Detected
PFHpS 9/12/2023 <3.00 ppt 3.00 ppt Not Detected
PFMPA 9/12/2023 <4.00 ppt 4.00 ppt Not Detected
PFHxS 9/12/2023 <3.00 ppt 3.00 ppt Not Detected
8:2 FTS 9/12/2023 <5.00 ppt 5.00 ppt Not Detected
PFBS 9/12/2023 <3.00 ppt 3.00 ppt Not Detected
PFHpA 9/12/2023 <3.00 ppt 3.00 ppt Not Detected
PFNA 9/12/2023 <4.00 ppt 4.00 ppt Not Detected

Health-based violations on San Francisco Regional Water System

10 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for CA3810001.

Sources: EPA SDWIS · California State Water Resources Control Board, Division of Drinking Water

Nationwide peers

16 violations · 600 served: nearest cross-state SDWIS matches.

What to do with San Francisco Regional Water System

Use this system's EPA-reported record as a starting filter, not a final verdict.

  • See how every tracked system in California compares on the same EPA violation measures. California systems
  • Check whether PFAS was detected at this system under UCMR5 testing. PFAS guide
  • Find and compare another public water system by name or PWSID. Search systems

EPA SDWIS and UCMR5 figures are informational only, not a substitute for a certified lab test of your own tap water.

Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater