How’s the River Today?
Our real-time gauges offer a microbial water quality assessment of the Chicago and Calumet rivers, based on data collected from water quality sensors. Updated every 15 minutes, they provide insight into current river conditions, helping you stay informed.
Main Stem
Near Michigan Avenue
Offline for Season
Offline
North Branch
Near Goose Island
Offline for Season
Offline
South Branch
Near Eleanor Boat House
Offline for Season
Offline
Calumet River
Near Blue Island
Offline for Season
Offline
H2NOW gauges communicate the results of our microbial water quality assessment using a rolling average of the latest 3 hours of sensor readings. The assessment is based on the estimated levels of fecal coliforms — a group of bacteria typically associated with the presence of human pathogens. If the 3-hour rolling average of fecal coliform levels are below 200 CFU/100 mL, we say that water quality is Good, meaning that it should be safe for people to touch it. If the 3 hour rolling average is above 200 but below 1000 CFU/100 mL, we recommend Low Caution, and if the rolling average is above 1000 CFU/100 mL — High Caution.
More on the gauge methodology

Real-Time Water
Quality Monitoring
H2NOW Chicago, an innovative new approach to real-time water quality monitoring in the Chicago rivers, which are a part of the Chicago Area Waterway System (CAWS). Launched by Current in 2021, the H2NOW platform tests leading edge sensing and analytic technologies to measure water quality parameters and communicate them with the public in real-time.
Four probes with embedded sensors collect data at four discrete locations along the Chicago and Calumet rivers, and a range of supporting technologies assist with data collection, transmission, analysis, and communication.
H2NOW aims to grow public understanding about river water quality, providing a foundation for Chicago residents and visitors to be empowered as informed, engaged river users and stewards.
Understanding Water Quality
What is your impression of the water quality of the CAWS? Perhaps you picture a waterway so polluted that you don’t even want to get close to it, let alone touch the water. Or maybe you think the rivers are now safe to swim in because of years of successful regulatory and cleanup efforts.
The reality of the Chicago rivers’ water quality, like many urban rivers, is somewhere in between. Most important: it is constantly changing. Historically, measures of microbial pollutants, such as fecal coliforms, had to be determined in a laboratory, requiring the water samples to be transported to the lab. This process takes time! The lag between sampling and results makes it difficult to know how safe it is to use the river for recreational activities. A new approach developed by Current uses sensor data to generate real-time “weather reports” to help people make better and safer choices.
We have installed a probe with embedded sensors in each branch of the Chicago River and in the Calumet River, along with a range of other technologies to assist with data collection, transmission, and analysis. H2NOW uses the real-time data to estimate fecal coliform numbers in the rivers and suggest the level of caution to be exercised when engaging in activities that put people in direct contact with the water.
An Innovative Partnership
H2NOW streams real-time water quality data that can be used to estimate fecal coliform levels in the CAWS rivers. It is the first real-time water quality monitoring project in the U.S. to measure microbial pollutants in an urban waterway.
This massive urban science project was built with the cooperation of dozens of partners, including our utilities, technology providers, advocacy and community groups, and philanthropic funders. Through the partnership of several organizations, H2NOW Chicago launched in September 2021, the first real-time water quality monitoring project in the U.S. to measure microbial pollutants in an urban waterway.
Follow along at #H2NOWChicago
Impact
By discovering, analyzing, and sharing water quality data, H2NOW Chicago accomplishes the following outcomes (click to expand)
1) H2NOW Chicago provides information to residents and visitors...
2) H2NOW Chicago fosters a better understanding of recent improvements in water quality...
3) H2NOW Chicago leverages growing public interest to foster a more productive CAWS...
4) H2NOW Chicago improves environmental stewardship of the waterways...
Next Steps
One of Current’s priorities is accelerating water technologies that have local impact and global significance by de-risking innovative, early-stage water technologies. Launching H2NOW is a critical first step towards expanding these groundbreaking technologies to other urban river and lake communities across the U.S. for greater social, environmental and economic impact.