Nitrate in Charles City, IA Drinking Water
Nitrate data for Charles City, Iowa · 7,446 residents · 1 ZIP code
Routine testing in Charles City, Iowa turned up Nitrate — samples from the public supply came back positive, placing this contaminant on the list of substances residents here have a concrete reason to look into.
Data: EPA SDWIS, CCR Reports, ECHO Last verified: 2026-05-14
Nitrate in Charles City Tap Water
Nitrate has been detected in Charles City, Iowa drinking water at a maximum level of 0.6 ppb — below the EPA MCL of 10 mg/L (as nitrogen).
This analysis covers 7,446 residents across 1 ZIP code in Charles City.
Charles City's overall water quality grade is D (52/100).
Is Nitrate in Charles City Water Safe?
Nitrate was detected in Charles City 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 nitrate levels further.
Nitrate Levels by ZIP Code
| ZIP Code | Nitrate Level | EPA Limit | Status |
|---|---|---|---|
| 50616 | 0.6 ppm | 10 mg/L (as nitrogen) | OK |
Average nitrate level across Charles City: 0.6 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 Charles City 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.