Is South Gate, CA tap water safe?
The short answer
None of the 3 utilities serving South Gate has a result above a legal limit or action level, or a health-based violation since 2016, in EPA’s and California’s records.
South Gate - City, Water Dept., which serves the most people here, has 2 results above EPA’s new limit, which takes effect in 2029 and 2 results above the health goal. The worst: PFOS at 26 ppt, above EPA’s new limit, which takes effect in 2029.
The water from South Gate - City, Water Dept. is hard to very hard depending on the source, 178 to 260 mg/L (10.4 to 15.2 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 South Gate’s ZIP codes, from EPA’s estimates.
- Open report
South Gate - City, Water Dept.
California · serves 88,544 people · nearly all in South Gate
2 results above EPA’s new limit, which takes effect in 2029 and 2 results above the health goal. The worst: PFOS at 26 ppt, above EPA’s new limit, which takes effect in 2029. Hardness: hard to very hard depending on the source, 178 to 260 mg/L (10.4 to 15.2 grains per gallon).
No health-based violations since 2016
- Open report
Gswc - Hollydale
California · serves 8,099 people · about 5,700 in South Gate
2 results above the health goal. The worst: Arsenic at 5.4 ppb, above the health goal. Hardness: very hard, typically 268 mg/L (15.6 grains per gallon).
No health-based violations since 2016
- Open report
Walnut Park Mutual Water Co.
California · serves 16,180 people · about 600 in South Gate
2 results above the health goal. The worst: Uranium at 5.7 ppb, above the health goal. Hardness: very hard, typically 205 mg/L (12 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 South Gate - City, Water Dept.’s water, which serves the most people here. Another utility’s report names what handles its own results.
Disclosure: TapBuff earns a commission if you buy through some links on this page. It does not change which standard or filter we name. As an Amazon Associate, TapBuff earns from qualifying purchases. How TapBuff makes money
Countertop reverse osmosis
- IAPMO listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 58NSF/ANSI 401checked Oct. 4, 2026
Certified for: PFOS, PFOA, 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: PFOS, PFOA, 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: PFOS, PFOA, Arsenic
Water testing near South Gate
The 3 labs California certifies closest to South Gate, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.
Los Angeles County Public Health Laboratory
Downey, CA · about 2 miles
Certified for bacteria
Michelson Laboratories, Inc.
Commerce, CA · about 4 miles
Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics
SGS Forensic Laboratories
Carson, CA · about 7 miles
Certified for metals
ZIP codes in South Gate
Which ZIP codes are in South Gate: 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 South Gate
Other towns in Los Angeles County with a page of their own.
What to do next
- Read South Gate - City, Water Dept.’s full reportEvery result with its dates, the violations, and the certification claim that handles each finding.Open the report
- Filters for PFOSRanked by certification and what they cost over five years.The best water filters for PFAS, ranked
- On a private well?No utility tests a well. A certified lab test is the first step.How to test well water