EPA SDWIS DataIllinois

Nitrite in Illinois Drinking Water

Illinois has 26,675 public water systems. 6737 have recorded nitrite violations.

Total Systems

26,675

With Violations

6,737

EPA MCL

1

Population Served

12.6M

Nitrite in Illinois: Key Facts

Total Water Systems

26,675

Systems with Violations

6,737

Lead Violations

91

Copper Violations

465

EPA Standard

1 mg/L as N

MCLG (goal): 1 mg/L

Water Systems with Violations in Illinois

SystemPopulationViolations
SKYVIEW ESTATES567512
STURM SBDV546146
WINDMILL ESTATES655042
CARMEL MONTESSORI ACADEMY404386
MARY SEARS ACADEMY LEMONT1153915
CRISWELL COURT MHP943770
IATREIA MENTAL HEALTH703665
TREASURE ISLAND MHP2403443

Health Effects of Nitrite Exposure

Blue baby syndrome

Can block oxygen in blood of infants under 6 months

Methemoglobinemia

Converts hemoglobin, reducing blood oxygen-carrying capacity

Infants below 6 months can develop methemoglobinemia ('blue baby syndrome'). Combined nitrate+nitrite limit is 10 mg/L.

Frequently Asked Questions

Is there nitrite in Illinois water?

Illinois has 26,675 public water systems. 6737 have recorded nitrite 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 Illinois water for nitrite?

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 nitrite?

The EPA Maximum Contaminant Level (MCL) for nitrite is 1 mg/L as N. Systems that exceed MCLs are required to notify customers and take corrective action.

Nitrite at a Glance

Categoryinorganic
EPA MCL1 mg/L as N

Source

Runoff from fertilizer use; leaching from septic tanks and sewage; erosion of natural deposits

How to Filter Nitrite

  • +Reverse osmosis removes nitrite
  • +Ion exchange systems can remove nitrite
  • +Do not give water with elevated nitrite to infants