Is Fontana, CA tap water safe?
The short answer
None of the 4 utilities serving Fontana has a result above a legal limit or action level, or a health-based violation since 2016, in EPA’s and California’s records.
San Gabriel Valley WC - Fontana, which serves the most people here, has 2 results above the health goal. The worst: Arsenic at 1.7 ppb, above the health goal. Health goals are stricter than legal limits and are not enforced.
The water from San Gabriel Valley WC - Fontana is moderately hard to very hard depending on the source, 90 to 234 mg/L (5.3 to 13.7 grains per gallon). How California’s water compares.
A town can be served by more than one utility, and some homes are on private wells. The name on your water bill tells you which is yours, and your ZIP code narrows it down. They are listed by how many people each serves in Fontana’s ZIP codes, from EPA’s estimates.
- Open report
San Gabriel Valley WC - Fontana
California · serves 228,270 people · about 158,600 in Fontana
2 results above the health goal. The worst: Arsenic at 1.7 ppb, above the health goal. Hardness: moderately hard to very hard depending on the source, 90 to 234 mg/L (5.3 to 13.7 grains per gallon).
No health-based violations since 2016
- Open report
Cucamonga Valley Water District
California · serves 213,375 people · about 12,800 in Fontana
3 results above the health goal. The worst: Nitrate at 16 ppm, above the health goal. Hardness: moderately hard to very hard depending on the source, 86 to 244 mg/L (5 to 14.3 grains per gallon).
No health-based violations since 2016
- Open report
West Valley Water District
California · serves 96,123 people · about 10,900 in Fontana
3 results above the health goal. The worst: Nitrate at 14 ppm, above the health goal. Hardness: moderately hard to very hard depending on the source, 88 to 245 mg/L (5.1 to 14.3 grains per gallon).
No health-based violations since 2016
- Open report
Marygold MWC
California · serves 3,155 people · about 1,800 in Fontana
Nothing in its records is above a health goal. Hardness: hard, typically 145 mg/L (8.5 grains per gallon).
No health-based violations since 2016
What handles it
Each of these is certified, on a certifier’s listing, for a result above a line in San Gabriel Valley WC - Fontana’s water, which serves the most people here. Another utility’s report names what handles its own results.
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Countertop reverse osmosis
- IAPMO listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 58NSF/ANSI 401checked Oct. 4, 2026
Certified for: Arsenic
Aquasana SmartFlow Reverse Osmosis (AQ-SFRO2)
Under-sink reverse osmosis
- WQA listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 58NSF/ANSI 401checked Oct. 9, 2026
Certified for: Arsenic
Brondell Capella RC250 Reverse Osmosis System
Under-sink reverse osmosis
- WQA listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 58NSF/ANSI 401checked Oct. 9, 2026
Certified for: Arsenic
Water testing near Fontana
The 3 labs California certifies closest to Fontana, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.
Clinical Laboratory of San Bernardino, Inc.
Grand Terrace, CA · about 9 miles
Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics, organic chemicals, disinfection byproducts, radioactivity
A & R Laboratories, Inc.
Ontario, CA · about 10 miles
Certified for bacteria
BSK Associates - San Bernardino Analytical Laboratory
San Bernardino, CA · about 11 miles
Certified for bacteria
Which ZIP codes are in Fontana: Census 2020 relationship files. Which utilities serve them, and how many people: EPA SDWIS and EPA’s service area map. Each utility’s results: EPA UCMR 5, EPA SDWIS, and EPA’s and the state’s compliance monitoring, as its report lists them. How they are measured: methodology. Certified labs: California State Water Resources Control Board, ELAP accredited laboratories and their fields of accreditation; distances from the Census 2020 ZIP code tabulation area gazetteer.
Near Fontana
Other towns in San Bernardino County with a page of their own.
What to do next
- Read San Gabriel Valley WC - Fontana’s full reportEvery result with its dates, the violations, and the certification claim that handles each finding.Open the report
- Filters for ArsenicRanked by certification and what they cost over five years.The best reverse osmosis systems, ranked
- On a private well?No utility tests a well. A certified lab test is the first step.How to test well water