Nitrate in Wisconsin Drinking Water
Wisconsin has 24,118 public water systems. 13271 have recorded nitrate violations.
Total Systems
24,118
With Violations
13,271
EPA MCL
10
Population Served
5.1M
Nitrate in Wisconsin: Key Facts
Total Water Systems
24,118
Systems with Violations
13,271
Lead Violations
59
Copper Violations
355
EPA Standard
10 mg/L as N
MCLG (goal): 10 mg/L
Water Systems with Violations in Wisconsin
| System | Population | Violations |
|---|---|---|
| WAUKESHA WATER UTILITY | 71K | 2969 |
| 52ND AVE WATER GROUP | 35 | 1760 |
| SOUTH PETERSON WELL ASSOC | 24 | 1446 |
| BROAD-A CORPORATION | 3 | 1306 |
| SILVER SPRING GOLF CENTER CLUBHOUSE | 600 | 1265 |
| SUSSEX VILLAGE HALL & WATER UTILITY | 12K | 1254 |
| MAPLE RIDGE ESTATES | 25 | 1161 |
| WILMOT UNION HIGH SCHOOL | 1K | 1121 |
Health Effects of Nitrate Exposure
Blue baby syndrome
Infants under 6 months can develop methemoglobinemia
Thyroid effects
May disrupt thyroid function with chronic exposure
Cancer links
Potential associations with colorectal cancer at high levels
Infants below 6 months can develop methemoglobinemia ('blue baby syndrome'). May also affect adults with certain conditions.
Frequently Asked Questions
Is there nitrate in Wisconsin water?
Wisconsin has 24,118 public water systems. 13271 have recorded nitrate violations based on EPA SDWIS data. If you are on a private well, your water is not covered by these regulations and should be tested independently.
How can I check my Wisconsin water for nitrate?
Search for your water system using the WaterCheck system lookup, or contact your utility and request a copy of your Consumer Confidence Report (CCR). The CCR is published annually and lists all detected contaminants, their levels, and the EPA MCLs. For private wells, contact a state-certified lab for independent testing.
What is the EPA limit for nitrate?
The EPA Maximum Contaminant Level (MCL) for nitrate is 10 mg/L as N. Systems that exceed MCLs are required to notify customers and take corrective action.
Nitrate at a Glance
Source
Runoff from fertilizer use; leaching from septic tanks and sewage; erosion of natural deposits
How to Filter Nitrate
- +Reverse osmosis or distillation removes nitrates
- +Boiling does NOT remove nitrates - it concentrates them
- +Do not give well water to infants under 6 months without testing