The City of Marengo is committed to providing safe, reliable, and high-quality drinking water to all residents. We are pleased to report that the City’s potable water supply meets or exceeds all applicable standards established by the State of Illinois and the federal government.
Our water system is regularly tested, monitored, and maintained in accordance with all state and federal requirements. These regulations are designed to ensure that public drinking water remains safe for consumption and that any contaminants are maintained at levels that do not pose a risk to public health.
Based on our continued compliance with these rigorous standards, residents can be confident in the safety and quality of Marengo’s drinking water. The City will continue to conduct routine testing and investing system maintenance and improvements to ensure the ongoing delivery of safe drinking water to our community.
Consumer Confidence Reports
- 2025 Consumer Confidence Report (CCR)
- 2024 Consumer Confidence Report (CCR)
- 2023 Consumer Confidence Report (CCR)
- 2022 Consumer Confidence Report (CCR)
- 2021 Consumer Confidence Report (CCR)
**Manganese Update – April 2026**
In October 2025, testing showed elevated manganese levels in parts of the system. As of April 1, 2026, levels have returned to within IEPA standards following system flushing and treatment adjustments.
**Well Sample Testing– The McHenry County Department of Health stopped offering discounted well sample testing to residents of McHenry County. To view of recommended laboratories, click HERE.
For questions about water quality, contact Public Works marengopublicworks@cityofmarengo.com
