Riverside, CA Water Quality (ZIP 92503)

Quick Answers

Is ZIP 92503 tap water safe to drink? PFAS compounds have been detected in 92503's water at an average of 5.61 ppt across 8 compounds. A certified pitcher filter or reverse osmosis system is recommended, especially for sensitive populations.

What filter should I use in 92503? Match the filter to the data: reverse osmosis handles PFAS, lead, and arsenic together; NSF-53 pitchers cover the taps you drink from. A basic Brita pitcher will not remove PFAS.

ZIP 92503 Water Quality Summary

EPA testing has detected PFAS "forever chemicals" in the water systems serving ZIP 92503 (Riverside, CA). Monitoring found a peak of 41 ppt across 4 systems, averaging 5.61 ppt over 8 detected compounds. These levels come from individual EPA UCMR 5 water samples (2023-2025). The EPA's 4 ppt limit for PFOA and PFOS is enforced on a running annual average, so a sample above it shows real exposure but is not by itself a violation.

Contamination Level: MODERATE – Moderate contamination – PFAS detected at meaningful levels; filtration recommended.

Top Detected Compounds in ZIP 92503

• PFOA: 41 ppt (exceeds the EPA 4 ppt limit)
• PFHPA: 14 ppt (exceeds the EPA 10 ppt limit)
• PFBA: 7 ppt (exceeds the EPA 4 ppt limit)
• PFPEA: 6.7 ppt (exceeds the EPA 4 ppt limit)
• PFOS: 5.7 ppt (exceeds the EPA 4 ppt limit)

Lead in ZIP 92503 Water

EPA Lead and Copper Rule testing recorded 20 lead samples for the systems serving 92503, with a 90th-percentile high of 0.0031 mg/L (within 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.

About the Data

These figures come from EPA UCMR5 (2023-2025) plus Lead and Copper Rule and SDWIS records for the public water system serving ZIP 92503. UCMR5 is the most comprehensive national drinking water survey in US history.

Beyond water: other exposures in Riverside, CA

Drinking water is one exposure route. These are the other federal datasets that cover ZIP 92503 and Riverside County, CA.

Radon risk in Riverside County, CA

The EPA places Riverside 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 Riverside County, CA

Census figures show 31% of homes in Riverside County, CA were built before 1980, and 4% 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 Riverside County, CA

Modelled annual fine-particle pollution (PM2.5) for Riverside County, CA averages 9.3 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.

Industrial releases near 92503

EPA Toxics Release Inventory data for 2023 records 1 reporting facility within about five miles of 92503, together reporting roughly 4,013 pounds of on-site chemical releases that year. TRI covers facilities above federal reporting thresholds, so smaller sources are not included, and a reported release is not the same as a measured concentration in air or water.