Is Green Valley, CA tap water safe?
The short answer
2 of the 4 utilities serving Green Valley have a result above a legal limit or action level, or a health-based violation since 2016, in EPA’s and California’s records: City of Fairfield and Green Valley CWD.
City of Fairfield, which serves the most people here, has 2 results above the health goal. The worst: Arsenic at 1.3 ppb, above the health goal. Health goals are stricter than legal limits and are not enforced.
The water from City of Fairfield is moderately hard to very hard depending on the source, 99 to 184 mg/L (5.8 to 10.7 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 Green Valley’s ZIP codes, from EPA’s estimates.
- Open report
City of Fairfield
California · serves 120,720 people · about 4,200 in Green Valley
2 results above the health goal. The worst: Arsenic at 1.3 ppb, above the health goal. Hardness: moderately hard to very hard depending on the source, 99 to 184 mg/L (5.8 to 10.7 grains per gallon).
1 health-based violation since 2016
- Open report
Santa Clarita Valley Water Agency
California · serves 292,014 people · about 220 in Green Valley
2 results above EPA’s new limit, which takes effect in 2029, 2 results above the health goal and 1 result above EPA’s health benchmark. The worst: PFOA at 16.9 ppt, above EPA’s new limit, which takes effect in 2029. Hardness: moderately hard to very hard depending on the source, 120 to 568 mg/L (7 to 33.2 grains per gallon).
No health-based violations since 2016
- Open report
Green Valley CWD
California · serves 1,275 people · under 100 in Green Valley
2 results above the health goal. The worst: Nitrate at 25.4 ppm, above the health goal. Hardness: hard to very hard depending on the source, 150 to 304 mg/L (8.8 to 17.8 grains per gallon).
1 health-based violation since 2016
- Open report
Sid - Blue Ridge Oaks
California · serves 63 people · under 100 in Green Valley
Nothing in its records is above a health goal.
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 City of Fairfield’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 Green Valley
The 3 labs California certifies closest to Green Valley, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.
Dellavalle Laboratory, Inc.
Fresno, CA · about 35 miles
Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics, radioactivity
Moore Twining Associates, Inc.
Fresno, CA · about 36 miles
Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics, organic chemicals, disinfection byproducts, radioactivity
BSK Associates
Fresno, CA · about 41 miles
Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics, organic chemicals, disinfection byproducts, PFAS, radioactivity
Which ZIP codes are in Green Valley: 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 Green Valley
Other towns in Los Angeles County with a page of their own.
What to do next
- Read City of Fairfield’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