💧 ZIP Water Report

Tap water in Walnut, CA — ZIP 91765

2 public water systems serving about 188,896 people. PFAS "forever chemicals" have been detected here.

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Excellent
PFAS detected: at least one system serving this ZIP reported PFAS in EPA UCMR 5 testing. Levels and the 2024 federal limits are shown per system below.

Water systems serving 91765

Walnut Valley Water District
PWSID CA1910234 · serves 100,941 · surface water
0 health-based / 0 total violations (5 yrs)
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Western Mwd
PWSID CA3310049 · serves 87,955 · surface water
0 health-based / 0 total violations (5 yrs) · PFAS up to 4.7 ppt
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Grades summarize EPA SDWIS violation records (last 5 years) and UCMR 5 PFAS results. They are informational, not a health determination. Methodology