Radium in Chula Vista, CA Drinking Water
Radium data for Chula Vista, California · 191,282 residents · 8 ZIP codes
If you rely on a public water system in Chula Vista, California, Radium is a contaminant your utility has been required to test for — and EPA records show it has been detected at measurable levels, making it worth understanding as part of your tap water's detection record.
Data: EPA SDWIS, CCR Reports, ECHO Last verified: 2026-05-14
Radium in Chula Vista Tap Water
Radium has been detected in Chula Vista, California drinking water at a maximum level of 9.2 pCi/L — 1.84x the EPA MCL.
This analysis covers 191,282 residents across 8 ZIP codes in Chula Vista.
Chula Vista's overall water quality grade is A (97/100).
Is Radium in Chula Vista Water Safe?
Radium was detected in Chula Vista water but currently falls within EPA limits. However, some health organizations argue the EPA MCL may not be protective enough.
If you are concerned, a reverse osmosis or ion exchange filter can reduce radium levels further.
Radium Levels by ZIP Code
| ZIP Code | Radium Level | EPA Limit | Status |
|---|---|---|---|
| 91909 | 9.2 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Exceeds limit |
| 91910 | 9.2 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Exceeds limit |
| 91911 | 9.2 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Exceeds limit |
| 91912 | 9.2 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Exceeds limit |
| 91913 | 9.2 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Exceeds limit |
| 91914 | 9.2 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Exceeds limit |
| 91921 | 9.2 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | Exceeds limit |
Average radium level across Chula Vista: 9.2 pCi/L
Health Effects of Radium
- Increased risk of bone cancer (radium accumulates in bones)
- The body treats radium like calcium, storing it in bones
- Lifetime cancer risk of ~1 in 10,000 at 5 pCi/L
- No safe threshold for radioactive contamination
Health risk severity: High. Governed by the Radionuclides Rule.
How Radium Gets Into Drinking Water
- Natural radioactive decay in underground rock formations
- Groundwater sources (especially deep wells)
- Mining and industrial waste
- Higher in regions with specific geology (Midwest, parts of South)
What to Do About Radium in Chula Vista Water
- Reverse osmosis (NSF 58 certified) removes 90%+ of radium
- Ion exchange (water softeners) can reduce radium
- Point-of-use RO at kitchen tap is most cost-effective
- GAC filters alone are NOT effective for radium
Look for filters certified under NSF 58 for radium removal.