Nitrate in Maryland Drinking Water — 11 ZIPs Tested
EPA data analysis for nitrate in Maryland drinking water systems
Nitrate Contamination in Maryland
ZipCheckup analyzed drinking water data across 615 ZIP codes in Maryland for nitrate contamination. 11 ZIP codes have reported nitrate detections, and 0 have EPA violations on record.
EPA Standard for Nitrate
The EPA maximum contaminant level (MCL) for nitrate is 10 mg/L (as nitrogen), governed by the National Primary Drinking Water Regulations. Water systems that exceed this limit must take corrective action and notify consumers.
Worst ZIP Codes for Nitrate in Maryland
These ZIP codes reported the highest nitrate levels in Maryland based on CCR reports and EPA data:
Lowest Nitrate Levels in Maryland
These ZIP codes had the lowest reported nitrate detections in Maryland:
Health Effects of Nitrate
How to Remove Nitrate From Drinking Water
The most effective treatment for nitrate removal is Reverse Osmosis or Ion Exchange. Look for filters certified under NSF 53 / NSF 58 standards.
Check Your ZIP Code
Use the ZipCheckup water quality search to see nitrate data for your specific water system in Maryland.
Worst ZIP Codes for Nitrate in Maryland
Ranked by highest nitrate detection level.
| Rank | ZIP Code | City | Level Detected | EPA Limit | Status |
|---|---|---|---|---|---|
| 1 | 21023 | Butler | 10 ppm | 10 ppm | Within Limit |
| 2 | 21074 | Hampstead | 10 ppm | 10 ppm | Within Limit |
| 3 | 21155 | Upperco | 10 ppm | 10 ppm | Within Limit |
| 4 | 21791 | Union Bridge | 6 ppm | 10 ppm | Within Limit |
| 5 | 21801 | Salisbury | 6 ppm | 10 ppm | Within Limit |
| 6 | 21802 | Salisbury | 6 ppm | 10 ppm | Within Limit |
| 7 | 21803 | Salisbury | 6 ppm | 10 ppm | Within Limit |
| 8 | 21804 | Salisbury | 6 ppm | 10 ppm | Within Limit |
| 9 | 21849 | Parsonsburg | 6 ppm | 10 ppm | Within Limit |
| 10 | 21157 | Westminster | 5.61 ppm | 10 ppm | Within Limit |
| 11 | 21158 | Westminster | 5.61 ppm | 10 ppm | Within Limit |
Lowest Nitrate Levels in Maryland
Cities with Nitrate Data in Maryland
5 cities in Maryland have nitrate testing data available.