Radionuclides · 2025
Gross Alpha in San Diego, City of, CA tap water
San Diego, City of, CA's 2025 Consumer Confidence Report shows Gross Alpha at or above the federal limit (15 PCI/L MCL). Measured value is 4.5× the threshold.
The measurement
| Statistic | Value | Federal limit |
|---|---|---|
Average Source water | 67.66666666666667 PCI/L | 15 PCI/L MCL |
Average Entry point | 4.44 PCI/L | 15 PCI/L MCL |
Average Other | 2.3 PCI/L | 15 PCI/L MCL |
Highest single sample Entry point | 4.44 PCI/L | 15 PCI/L MCL |
Highest single sample Other | 2.3 PCI/L | 15 PCI/L MCL |
Highest single sample Source water | 73.3 PCI/L | 15 PCI/L MCL |
Verbatim from San Diego, City of, CA's 2025 Consumer Confidence Report — source document ↗
About Gross Alpha
Gross alpha particle activity — a combined measure of alpha-emitting radioactive substances.
Long-term exposure above the federal limit increases cancer risk.
How San Diego, City of, CA compares
5 of the 246 systems measuring Gross Alpha on The Water Map have it at or above the federal limit:
Nearby systems also reporting Gross Alpha:
People also ask
+Is there Gross Alpha in San Diego, City of, CA tap water?
Yes — San Diego, City of, CA's 2025 Consumer Confidence Report lists Gross Alpha at 67.66666666666667 PCI/L. San Diego, City of, CA's 2025 Consumer Confidence Report shows Gross Alpha at or above the federal limit (15 PCI/L MCL). Measured value is 4.5× the threshold.
+What's the federal limit for Gross Alpha in drinking water?
The federal MCL for Gross Alpha is 15 PCI/L. The EPA enforces this against the regulated reporting statistic (running annual average or 90th percentile), not a single-sample spike.
+What is Gross Alpha?
Gross alpha particle activity — a combined measure of alpha-emitting radioactive substances. Long-term exposure above the federal limit increases cancer risk.
+Which other U.S. cities have Gross Alpha over the federal limit?
5 of the 246 systems on The Water Map measuring Gross Alpha report it at or above the federal limit. Examples include Birmingham, AL, Rancho Estates Mutual Water Co., CA, Saticoy Country Club-city of Ventura, CA.
+Where does this Gross Alpha measurement come from?
This page reproduces the Gross Alpha entry from the 2025 Consumer Confidence Report published by the San Diego, City of, CA water utility — the annual drinking-water report every U.S. utility is required by federal law to publish. The original source document is archived at /water/ca/san-diego/2025/source.