Water Quality Report · Updated October 07, 2026
CITY OF SUNNYVALE
CITY OF SUNNYVALE delivers tap water graded D (64/100) by TapWaterSafety.org. The utility serves approximately 157,566 residents in SUNNYVALE, California using surface water (purchased). The most significant water quality concerns are: Haloacetic acids (HAA9) significantly above health guideline; Haloacetic acids (HAA5) significantly above health guideline; Total trihalomethanes (TTHMs) significantly above health guideline. For questions, the utility can be reached at 408-730-7561.
Is SUNNYVALE tap water safe to drink?
CITY OF SUNNYVALE delivers tap water that earns a grade of D (64/100) from TapWaterSafety.org — a below-average rating, with multiple concerns including haloacetic acids (haa9) significantly above health guideline.
The utility serves 157,566 residents in SUNNYVALE, drawing from surface water (purchased).
Public testing data identifies 13 contaminants in this water above EWG's health-based guidelines, including: Haloacetic acids (HAA9), Haloacetic acids (HAA5), Total trihalomethanes (TTHMs), Bromodichloromethane, Dibromoacetic acid, Dibromochloromethane, Trichloroacetic acid, Chloroform, Dichloroacetic acid, Chromium (hexavalent), Nitrate, Nitrate and nitrite, Bromoform. 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 CITY OF SUNNYVALE (system ID CA4310014) for the last 3 years. Checked 2026-10-07.
| Rule | Type | Since | Status |
|---|---|---|---|
| Nitrate Rule | Missed testing or reporting | 01/01/2015 | Open |
| Synthetic Organic Chemicals | Missed testing or reporting | 01/01/2015 | Open |
| Volatile Organic Chemicals | Missed testing or reporting | 01/01/2015 | Open |
| Inorganic Chemicals | Missed testing or reporting | 01/01/2015 | Open |
| Arsenic Rule | Missed testing or reporting | 01/01/2015 | Open |
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 SUNNYVALE residents
Top concerns in this water
Based on the most recent EPA and EWG data, these are the most significant water quality issues for CITY OF SUNNYVALE.
Haloacetic acids (HAA9) significantly above health guideline
Moderate concernHaloacetic acids (HAA9) detected at 32.8 ppb, 547x above the EWG health guideline of 0.06 ppb.
Haloacetic acids (HAA5) significantly above health guideline
Moderate concernHaloacetic acids (HAA5) detected at 36.2 ppb, 362x above the EWG health guideline of 0.1 ppb.
Total trihalomethanes (TTHMs) significantly above health guideline
Moderate concernTotal trihalomethanes (TTHMs) detected at 51.7 ppb, 344x above the EWG health guideline of 0.15 ppb.
Contact CITY OF SUNNYVALE
Reach the utility directly for service issues, water quality concerns, or to request your Consumer Confidence Report.
General Contact
Recommended water filters for SUNNYVALE
Filters matched to the specific contaminants in this water supply.
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 64/100 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 |
|---|---|---|---|---|---|---|---|---|
| Haloacetic acids (HAA9) Disinfection byproduct |
32.8 ppb | 0.06 | — | — | — | — | — | 547× over |
| Haloacetic acids (HAA5) Disinfection byproduct |
36.2 ppb | 0.1 | 60.0 | 60 | — | — | — | 362× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
51.7 ppb | 0.15 | 80.0 | 100 | — | — | — | 344× over |
| Bromodichloromethane Disinfection byproduct |
10.2 ppb | 0.06 | — | — | — | — | — | 171× over |
| Dibromoacetic acid Disinfection byproduct |
4.68 ppb | 0.03 | — | — | — | — | — | 156× over |
| Dibromochloromethane Disinfection byproduct |
14.0 ppb | 0.1 | — | — | — | — | — | 140× over |
| Trichloroacetic acid Disinfection byproduct |
6.35 ppb | 0.1 | — | — | — | — | — | 63× over |
| Chloroform Disinfection byproduct |
20.7 ppb | 0.4 | — | — | — | — | — | 52× over |
| Dichloroacetic acid Disinfection byproduct |
9.26 ppb | 0.2 | — | — | — | — | — | 46× over |
| Chromium (hexavalent) Heavy metal |
0.778 ppb | 0.02 | — | — | — | — | — | 39× over |
| Nitrate Inorganic |
3.44 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 25× over |
| Nitrate and nitrite Inorganic |
3.17 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 23× over |
| Bromoform Disinfection byproduct |
6.68 ppb | 0.5 | — | — | — | — | — | 13× over |
| Chlorate Disinfection byproduct |
112.6 ppb | 210.0 | — | — | — | — | — | Below guideline |
| Vanadium Other |
2.29 ppb | 21.0 | — | — | — | — | — | Below guideline |
| Barium Heavy metal |
53.3 ppb | 700.0 | 2000.0 | — | 1300 | 2000 | — | Below guideline |
| Molybdenum Other |
1.15 ppb | 40.0 | — | — | — | — | — | Below guideline |
| Monobromoacetic acid Disinfection byproduct |
0.433 ppb | 25.0 | — | — | — | — | — | Below guideline |
| Manganese Heavy metal |
0.574 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Monochloroacetic acid Disinfection byproduct |
0.0306 ppb | 53.0 | — | — | — | — | — | Below guideline |
| Strontium Radiological |
0.305 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| 1-Butanol Other |
0.115 ppb | — | — | — | — | — | — | Below guideline |
| Alpha-hexachlorocyclohexane Radiological |
0.0008 ppb | — | — | — | — | — | — | Below guideline |
| Chlorodifluoromethane Other |
0.203 ppb | — | — | — | — | — | — | Below guideline |
| Fluoride Inorganic |
0.155 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.
CITY OF SUNNYVALE service area
This water system serves 1 community in Santa Clara County, California. Click any city for its dedicated tap water quality page.
Find the right filter for SUNNYVALE water
Browse filter categories by water-quality concern. Each option below is NSF-certified for the matched contaminant type.