Tap Water Quality Report
Tap water quality in NOVATO, California
Tap water in NOVATO, California receives a grade of C (74/100) from TapWaterSafety.org. It's served by NORTH MARIN WATER DISTRICT. The most significant water quality concerns are: Haloacetic acids (HAA5) significantly above health guideline; Haloacetic acids (HAA9) significantly above health guideline; Total trihalomethanes (TTHMs) significantly above health guideline; Arsenic detected. Data sources: EPA SDWIS, EPA ECHO, EWG Tap Water Database.
What's in NOVATO's tap water
Top water quality concerns identified by the EPA and Environmental Working Group across the utility serving NOVATO.
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.
Haloacetic acids (HAA9) significantly above health guideline
Moderate concernHaloacetic acids (HAA9) detected at 14.6 ppb, 243x above the EWG health guideline of 0.06 ppb.
Total trihalomethanes (TTHMs) significantly above health guideline
Moderate concernTotal trihalomethanes (TTHMs) detected at 29.1 ppb, 194x above the EWG health guideline of 0.15 ppb.
Arsenic detected
Moderate concernArsenic detected at 0.37 ppb.
EPA compliance record
Official U.S. EPA records for NORTH MARIN WATER DISTRICT (system ID CA2110003) 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.
Recommended filters for NOVATO
Filters matched to the specific contaminants in NOVATO's 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.
Reverse osmosis certified for arsenic (NSF/ANSI 58)
$429-$599Reverse osmosis certified under NSF/ANSI 58 for arsenic is the most reliable home option.
Disclosure: TapWaterSafety earns a commission from purchases made through these links. This does not influence our scoring methodology or filter selection.
All contaminants detected in NOVATO's tap water
Every contaminant identified, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal. 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 (HAA5) Disinfection byproduct |
36.2 ppb | 0.1 | 60.0 | 60 | — | — | — | 362× over |
| Haloacetic acids (HAA9) Disinfection byproduct |
14.6 ppb | 0.06 | — | — | — | — | — | 243× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
29.1 ppb | 0.15 | 80.0 | 100 | — | — | — | 194× over |
| Bromodichloromethane Disinfection byproduct |
8.37 ppb | 0.06 | — | — | — | — | — | 139× over |
| Arsenic Heavy metal |
0.37 ppb | 0.004 | 10.0 | 10 | 10 | 0.004 | — | 93× over |
| Dibromoacetic acid Disinfection byproduct |
1.76 ppb | 0.03 | — | — | — | — | — | 59× over |
| Dibromochloromethane Disinfection byproduct |
5.57 ppb | 0.1 | — | — | — | — | — | 56× over |
| Chloroform Disinfection byproduct |
14.1 ppb | 0.4 | — | — | — | — | — | 35× over |
| Trichloroacetic acid Disinfection byproduct |
3.26 ppb | 0.1 | — | — | — | — | — | 33× over |
| Dichloroacetic acid Disinfection byproduct |
4.93 ppb | 0.2 | — | — | — | — | — | 25× over |
| Chromium (hexavalent) Heavy metal |
0.221 ppb | 0.02 | — | — | — | — | — | 11× over |
| Bromoform Disinfection byproduct |
1.06 ppb | 0.5 | — | — | — | — | — | 2.1× over |
| Chlorate Disinfection byproduct |
117.8 ppb | 210.0 | — | — | — | — | — | Below guideline |
| Vanadium Other |
0.502 ppb | 21.0 | — | — | — | — | — | Below guideline |
| Barium Heavy metal |
10.7 ppb | 700.0 | 2000.0 | — | 1300 | 2000 | — | Below guideline |
| Manganese Heavy metal |
0.559 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Strontium Radiological |
0.196 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| Fluoride Inorganic |
0.125 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, California OEHHA PHGs, EWG Tap Water Database.
Treatment plant contact info
For service issues, water quality concerns, or to request a Consumer Confidence Report from NORTH MARIN WATER DISTRICT.