Nitrate in San Fernando, CA Drinking Water
Nitrate data for San Fernando, California · 33,750 residents · 2 ZIP codes
Recent water testing in San Fernando, California has returned Nitrate readings above detection thresholds.
Data: EPA SDWIS, CCR Reports, ECHO Last verified: 2026-04-05
Nitrate in San Fernando Tap Water
Nitrate has been detected in San Fernando, California drinking water at a maximum level of 45 ppb — below the EPA MCL of 10 mg/L (as nitrogen).
This analysis covers 33,750 residents across 2 ZIP codes in San Fernando.
San Fernando's overall water quality grade is B (83/100).
Is Nitrate in San Fernando Water Safe?
If you live in an affected ZIP code, consider installing a reverse osmosis or ion exchange filter certified under NSF 53 / NSF 58 and testing your water independently.
Nitrate Levels by ZIP Code
| ZIP Code | Nitrate Level | EPA Limit | Status |
|---|---|---|---|
| 91340 | 45 ppm | 10 mg/L (as nitrogen) | OK |
| 91341 | 45 ppm | 10 mg/L (as nitrogen) | OK |
Average nitrate level across San Fernando: 45 ppb
Health Effects of Nitrate
- Methemoglobinemia ("blue baby syndrome") in infants under 6 months
- Increased risk of colorectal and bladder cancer (long-term)
- Thyroid disease from chronic exposure
- Possible reproductive effects
Health risk severity: High. Governed by the National Primary Drinking Water Regulations.
How Nitrate Gets Into Drinking Water
- Agricultural fertilizer runoff
- Animal feedlot operations and manure
- Septic system leachate
- Urban stormwater and wastewater discharge
What to Do About Nitrate in San Fernando Water
- Reverse osmosis is the most effective method for nitrate removal
- Ion exchange systems designed for nitrate can also work
- Standard carbon filters do NOT remove nitrate
- Boiling water increases nitrate concentration — never boil for nitrate
Look for filters certified under NSF 53 / NSF 58 for nitrate removal.