Water Quality Report · Updated October 07, 2026
DUBLIN SAN RAMON SERVICES DISTRICT
DUBLIN SAN RAMON SERVICES DISTRICT delivers tap water graded F (50/100) by TapWaterSafety.org. The utility serves approximately 98,776 residents in PLEASANTON, California using surface water (purchased). The most significant water quality concerns are: PFAS contamination; Perfluorohexane sulfonate (PFHXS)* significantly above health guideline; Arsenic* significantly above health guideline; Haloacetic acids (HAA5) significantly above health guideline. For questions, the utility can be reached at 925-875-2371.
Is PLEASANTON tap water safe to drink?
DUBLIN SAN RAMON SERVICES DISTRICT delivers tap water that earns a grade of F (50/100) from TapWaterSafety.org — a poor rating, with significant contamination concerns and/or recent violations.
The utility serves 98,776 residents in PLEASANTON, drawing from surface water (purchased).
Public testing data identifies 21 contaminants in this water above EWG's health-based guidelines, including: Perfluorohexane sulfonate (PFHXS)*, Perfluorooctane sulfonate (PFOS)*, Arsenic*, Haloacetic acids (HAA5), Haloacetic acids (HAA9), Total trihalomethanes (TTHMs), Chromium (hexavalent), Perfluoroheptane sulfonic acid (PFHpS)*, Dibromoacetic acid, Bromodichloromethane, Dibromochloromethane, Perfluorooctanoic acid (PFOA)*, Dichloroacetic acid, Chloroform, Trichloroacetic acid, Nitrate*, Bromoform, Bromate*, Perfluoropentane sulfonic acid (PFPeS)*, Uranium*, N-Nitrosodimethylamine (NDMA)*. For most residents, a properly certified home filter at the kitchen tap is the most cost-effective way to reduce exposure to whatever's in your water. See our filter recommendations below, matched specifically to this utility's contaminant profile.
EPA compliance record
Official U.S. EPA records for DUBLIN SAN RAMON SERVICES DISTRICT (system ID CA0110009) for the last 3 years. Checked 2026-10-07.
Source: U.S. EPA Enforcement and Compliance History Online (ECHO), from the Safe Drinking Water Information System. See EPA's full report.
Quick actions for PLEASANTON residents
Top concerns in this water
Based on the most recent EPA and EWG data, these are the most significant water quality issues for DUBLIN SAN RAMON SERVICES DISTRICT.
PFAS contamination
Severe concernPerfluorooctane sulfonate (PFOS)*, Perfluorooctanoic acid (PFOA)* detected. PFAS are persistent chemicals linked to cancer and immune effects with no known safe exposure threshold.
Perfluorohexane sulfonate (PFHXS)* significantly above health guideline
Moderate concernPerfluorohexane sulfonate (PFHXS)* detected at 20.8 ppt, 20750x above the EWG health guideline of 0.001 ppt.
Arsenic* significantly above health guideline
Moderate concernArsenic* detected at 1.42 ppb, 355x above the EWG health guideline of 0.004 ppb.
Haloacetic acids (HAA5) significantly above health guideline
Moderate concernHaloacetic acids (HAA5) detected at 35.5 ppb, 355x above the EWG health guideline of 0.1 ppb.
Contact DUBLIN SAN RAMON SERVICES DISTRICT
Reach the utility directly for service issues, water quality concerns, or to request your Consumer Confidence Report.
General Contact
Treatment Plant
Recommended water filters for PLEASANTON
Filters matched to the specific contaminants in this water supply.
Filter certified for PFOA/PFOS (NSF/ANSI 53 or 58)
$180-$750Reverse osmosis and some carbon block filters reduce PFAS. Look for certification to NSF/ANSI 53 or 58 for PFOA/PFOS.
Reverse osmosis certified for arsenic (NSF/ANSI 58)
$429-$599Reverse osmosis certified under NSF/ANSI 58 for arsenic is the most reliable home option.
Carbon filter certified for VOCs (NSF/ANSI 53)
$180-$599Activated carbon is effective for disinfection byproducts. Look for NSF/ANSI 53 VOC reduction.
Disclosure: TapWaterSafety earns a commission from purchases made through these links. This does not influence our scoring methodology or filter selection.
Score breakdown
This utility's overall score of 50/100 breaks down across five weighted components. Read the full methodology →
Contaminants detected — international standards comparison
Every contaminant detected, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal (the strictest US benchmark). Why we show multiple standards →
| Contaminant | Detected | EWG US health-based |
EPA US legal |
EU DWD Europe |
WHO global |
CA PHG strictest US |
Tested sample year |
Status |
|---|---|---|---|---|---|---|---|---|
| Perfluorohexane sulfonate (PFHXS)* PFAS |
20.8 ppt | 0.001 | 10.0 | — | — | — | — | EPA violation |
| Perfluorooctane sulfonate (PFOS)* PFAS |
25.2 ppt | 0.3 | 4.0 | 100 | 100 | 1 | — | EPA violation |
| Arsenic* Heavy metal |
1.42 ppb | 0.004 | 10.0 | 10 | 10 | 0.004 | — | 355× over |
| Haloacetic acids (HAA5) Disinfection byproduct |
35.5 ppb | 0.1 | 60.0 | 60 | — | — | — | 355× over |
| Haloacetic acids (HAA9) Disinfection byproduct |
7.67 ppb | 0.06 | — | — | — | — | — | 128× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
14.6 ppb | 0.15 | 80.0 | 100 | — | — | — | 98× over |
| Chromium (hexavalent) Heavy metal |
1.94 ppb | 0.02 | — | — | — | — | — | 97× over |
| Perfluoroheptane sulfonic acid (PFHpS)* PFAS |
0.09 ppt | 0.001 | — | — | — | — | — | 90× over |
| Dibromoacetic acid Disinfection byproduct |
2.32 ppb | 0.03 | — | — | — | — | — | 77× over |
| Bromodichloromethane Disinfection byproduct |
4.14 ppb | 0.06 | — | — | — | — | — | 69× over |
| Dibromochloromethane Disinfection byproduct |
3.25 ppb | 0.1 | — | — | — | — | — | 33× over |
| Perfluorooctanoic acid (PFOA)* PFAS |
2.95 ppt | 0.09 | 4.0 | 100 | 100 | 0.007 | — | 33× over |
| Dichloroacetic acid Disinfection byproduct |
5.81 ppb | 0.2 | — | — | — | — | — | 29× over |
| Chloroform Disinfection byproduct |
5.0 ppb | 0.4 | — | — | — | — | — | 12× over |
| Trichloroacetic acid Disinfection byproduct |
1.21 ppb | 0.1 | — | — | — | — | — | 12× over |
| Nitrate* Inorganic |
1.21 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 8.6× over |
| Bromoform Disinfection byproduct |
1.98 ppb | 0.5 | — | — | — | — | — | 4.0× over |
| Bromate* Disinfection byproduct |
0.241 ppb | 0.1 | 10.0 | 10 | 10 | 0.1 | — | 2.4× over |
| Perfluoropentane sulfonic acid (PFPeS)* PFAS |
2.12 ppt | 1.0 | — | — | — | — | — | 2.1× over |
| Uranium* Radiological |
0.65 pCi/L | 0.43 | 20.0 | 30 | 30 | 0.43 | — | 1.5× over |
| N-Nitrosodimethylamine (NDMA)* Other |
3.1 ppt | 3.0 | — | — | — | — | — | 1.0× over |
| Chlorate Disinfection byproduct |
183.8 ppb | 210.0 | — | — | — | — | — | Below guideline |
| Aluminum* Heavy metal |
70.9 ppb | 600.0 | — | 200 | — | 600 | — | Below guideline |
| Barium* Heavy metal |
62.5 ppb | 700.0 | 2000.0 | — | 1300 | 2000 | — | Below guideline |
| Thallium* Heavy metal |
0.00804 ppb | 0.1 | 2.0 | — | — | — | — | Below guideline |
| Vanadium Other |
0.918 ppb | 21.0 | — | — | — | — | — | Below guideline |
| Selenium* Heavy metal |
0.741 ppb | 30.0 | 50.0 | 20 | 40 | 30 | — | Below guideline |
| Molybdenum Other |
0.588 ppb | 40.0 | — | — | — | — | — | Below guideline |
| Monochloroacetic acid Disinfection byproduct |
0.646 ppb | 53.0 | — | — | — | — | — | Below guideline |
| Beryllium* Heavy metal |
0.00893 ppb | 1.0 | 4.0 | — | — | 1 | — | Below guideline |
| Monobromoacetic acid Disinfection byproduct |
0.15 ppb | 25.0 | — | — | — | — | — | Below guideline |
| Perfluorohexanoic Acid (PFHxA)* PFAS |
3.67 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluorobutane sulfonate (PFBS)* PFAS |
4.51 ppt | 2000.0 | — | — | — | — | — | Below guideline |
| Perfluorobutanoic Acid (PFBA)* PFAS |
1.31 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Manganese Heavy metal |
0.113 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Perfluoropentanoic Acid (PFPeA)* PFAS |
1.06 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluoroheptanoic acid (PFHPA)* PFAS |
0.638 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Strontium Radiological |
0.343 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| Bromide* Other |
227.4 ppb | — | — | — | — | — | — | Below guideline |
| Chromium (total)* Heavy metal |
0.254 ppb | — | 100.0 | — | — | — | — | Below guideline |
| Fluoride Inorganic |
0.747 ppm | — | 4.0 | 1.5 | 1.5 | — | — | Below guideline |
All values in the unit of the detected level. Red cells indicate the detected level exceeds that standard. Some contaminants have limits in some jurisdictions but not others (shown as —). The "Tested" column shows the year each contaminant sample was collected.
Sources: US EPA, EU Drinking Water Directive 2020/2184, WHO Guidelines (4th ed.), California OEHHA PHGs, EWG Tap Water Database.
DUBLIN SAN RAMON SERVICES DISTRICT service area
This water system serves 1 community in Alameda County, California. Click any city for its dedicated tap water quality page.
Find the right filter for PLEASANTON water
Browse filter categories by water-quality concern. Each option below is NSF-certified for the matched contaminant type.