Radium in Rockville, MD Drinking Water
Radium data for Rockville, Maryland · 144,320 residents · 8 ZIP codes
Within Rockville, Maryland, Radium has been detected in water samples drawn from the public supply — the results are part of the official EPA compliance record for systems here.
Data: EPA SDWIS, CCR Reports, ECHO Last verified: 2026-06-04
Radium in Rockville Tap Water
Radium has been detected in Rockville, Maryland drinking water at a maximum level of 4 pCi/L — below the EPA MCL of 5 pCi/L (combined Ra-226 + Ra-228).
This analysis covers 144,320 residents across 8 ZIP codes in Rockville.
Rockville's overall water quality grade is D (45/100).
Is Radium in Rockville Water Safe?
Radium was detected in Rockville 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 |
|---|---|---|---|
| 20848 | 4 pCi/L | 5 pCi/L (combined Ra-226 + Ra-228) | OK |
Average radium level across Rockville: 4 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 Rockville 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.