Pasadena, CA Water Quality (ZIP 91101)

Quick Answers

Is ZIP 91101 tap water safe to drink? No PFAS above thresholds is reported for 91101 in current EPA data. Lead risk from older plumbing is a separate question; the results below cover the regulated contaminants tested for this system.

What filter should I use in 91101? A reverse osmosis system (NSF/ANSI 58) removes 90%+ of PFAS, lead, and arsenic. For smaller households, an NSF-53 certified pitcher (Clearly Filtered, ZeroWater) works. Standard Brita cartridges are not certified for PFAS.

ZIP 91101 Water Quality Summary

The public water system serving ZIP 91101 (Pasadena, CA) is not currently reported as having detected PFAS in recent EPA UCMR5 testing, though other regulated contaminants appear in the data below.

Contamination Level: NONE – No PFAS detected in recent testing for the systems serving this ZIP code.

Lead in ZIP 91101 Water

EPA Lead and Copper Rule testing recorded 13 lead samples for the systems serving 91101, with a 90th-percentile high of 0.036 mg/L (above the EPA 0.015 mg/L action level). There is no safe level of lead for children; homes built before 1986 should use a certified NSF/ANSI 53 lead filter.

EPA Violations Affecting ZIP 91101

The water systems serving 91101 have 23 health-based EPA Safe Drinking Water Act violations on record, including Chromium, Selenium, Lead. A health-based violation means a contaminant exceeded its federal limit or required treatment was not applied.

About the Data

Source: EPA UCMR5 monitoring (2023-2025), Lead and Copper Rule samples, and SDWIS violation records tied to the water system that serves 91101 in Pasadena, CA.

Beyond water: other exposures in Pasadena, CA

Drinking water is one exposure route. These are the other federal datasets that cover ZIP 91101 and Los Angeles County, CA.

Radon risk in Los Angeles County, CA

The EPA places Los Angeles County, CA in Zone 2 - a moderate-risk category, with a predicted average indoor radon level between 2 and 4 pCi/L. Zone maps predict the radon potential of an area from geology and existing indoor readings - they do not describe any individual home. Radon is the leading cause of lung cancer among people who have never smoked, and the only way to know your own level is a test kit.

Lead paint risk in Los Angeles County, CA

Census figures show 72% of homes in Los Angeles County, CA were built before 1980, and 24% before 1950. Lead-based paint was banned for residential use in 1978, so older housing stock is the strongest available proxy for lead-paint exposure. This is a statistic about the county's housing, not a test of any particular property - if your home predates 1980, a lead swab test is the way to check.

Air quality in Los Angeles County, CA

Modelled annual fine-particle pollution (PM2.5) for Los Angeles County, CA averages 10.6 µg/m³, above the EPA's annual PM2.5 standard of 9 µg/m³. PM2.5 is the pollution fraction small enough to reach deep into the lungs. These are CDC modelled estimates for the county as a whole, not a reading taken at this ZIP code.

Superfund sites near 91101

There are 2 EPA Superfund (National Priorities List) sites within about five miles of 91101: San Gabriel Valley (Area 3) (about 3.3 miles); Jet Propulsion Laboratory (NASA) (about 4.1 miles). Distances are measured from the ZIP code's geographic centre, so the distance from a specific address will differ. Proximity to a listed site is a fact about location - it is not itself evidence of exposure.