Is Ansonia, CT tap water safe?
The short answer
Neither of the 2 utilities serving Ansonia has a result above a legal limit or action level, or a health-based violation since 2016, in EPA’s and CDC’s records.
Regional Water Authority, 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 10.7 ppt, above EPA’s new limit, which takes effect in 2029.
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 Ansonia’s ZIP codes, from EPA’s estimates.
- Open report
Regional Water Authority
Connecticut · serves 418,900 people · about 18,700 in Ansonia
2 results above EPA’s new limit, which takes effect in 2029 and 2 results above the health goal. The worst: PFOS at 10.7 ppt, above EPA’s new limit, which takes effect in 2029.
No health-based violations since 2016
- Open report
Aquarion - Valley
Connecticut · serves 13,080 people · lists Ansonia among the places it serves
2 results above EPA’s new limit, which takes effect in 2029 and 1 result above the health goal. The worst: PFOA at 8.1 ppt, above EPA’s new limit, which takes effect in 2029.
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 Regional Water Authority’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: 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 Ansonia
The 3 labs Connecticut certifies closest to Ansonia, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.
Aquatek Labs, Inc.
Woodbridge, CT · about 4 miles
Certified for bacteria, nitrate, metals, minerals and other inorganics, organic chemicals, radioactivity
Aquarion Water Trap Falls Water Quality Lab
Shelton, CT · about 5 miles
Certified for bacteria
Regional Water Authority
New Haven, CT · about 8 miles
Certified for bacteria, nitrate, metals, minerals and other inorganics, organic chemicals, disinfection byproducts, PFAS
ZIP codes in Ansonia
Which ZIP codes are in Ansonia: 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: Connecticut DPH, approved commercial laboratories certified to test drinking water; distances from the Census 2020 ZIP code tabulation area gazetteer.
Near Ansonia
Other towns in New Haven County with a page of their own.
What to do next
- Read Regional Water Authority’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