Chicago River water monitoring tool back for Summer 2022

July 19, 2022
H2NOW reports on water quality from three locations every 15 minutes, providing helpful information to communities along the river.

The Metropolitan Water Reclamation District of Greater Chicago (MWRD) has announced that H2NOW, the Chicago River’s first real-time monitoring tool, is back for Summer 2022 with improvements that make it more powerful and useful.

The platform is providing a guide to water quality by estimating fecal coliform levels every 15 minutes from three spots along the river, through an array of novel technologies. The resource is available at

In addition to upgraded technology, new this year is a QR code that allows residents and river users to get to the platform immediately to check water quality. The code will be displayed on promotional materials and on signage along the river.

H2NOW was first launched in September 2021 by water technology company Current. The company is now leading H2NOW operations with the support of more than 20 partners.

Building and launching H2NOW was the result of collaboration among more than 20 partners, including the Metropolitan Water Reclamation District of Greater Chicago, which protects and monitors waterways and oversees wastewater treatment and stormwater management for Chicago and 128 suburbs, and the City of Chicago’s Department of Water Management, which is responsible for delivering drinking water to the city and 125 suburbs and collecting wastewater and stormwater through local sewers for transport to MWRD’s treatment facilities.

The system relies on innovative technologies that have not been previously deployed in an urban river and helps connect residents to their environment.

Sensitive probes have been installed in three locations and collect a series of measurements to estimate fecal coliform levels. Data are then transmitted and displayed on the H2NOW portal.

“Everyone who lives near or uses the Chicago River has a stake in its health and safety,” said Alaina Harkness, executive director of Current. “The more information we have about water quality, the more we can each do our part to keep this tremendous resource healthy.”

Since last fall, Current has upgraded its approach to translating sensor data into real-time water quality assessments using the best available science, and has redesigned the online gauges to deliver information to visitors and residents in a more usable and readable way.

Sensor equipment was removed last winter and reinstalled in May with additional features that enable H2NOW to provide an even better prediction of bacterial levels.

Upgraded probes are now collecting data on colored dissolved organic matter, or CDOM, as well as specific conductivity. Those readings are combined with measures of tryptophan-like fluorescence [TLF], temperature, and turbidity to provide an overall quality estimate. On the newly designed display gauges, water quality is considered “Good” or safe for contact if estimated fecal coliform levels are below 200 CFU/100 mL. If fecal coliform estimates range between 200 and 1000 CFU/100 mL, gauges display a “Low Caution” reading. Above 1000 CFU/100 mL, a “High Caution” warning is displayed. The “Good” threshold is based on the Illinois Environmental Protection Agency’s Primary Contact Use standard value, indicating that one is unlikely to get sick if river water is ingested.

“The Chicago River connects our communities,” said MWRD Board of Commissioners President Kari K. Steele. “H2NOW helps us make informed decisions about how we interact with the river.”

Fecal matter pollutes the Chicago River in two main ways. First, rainwater that falls over 1,834 square miles from Wisconsin to Indiana drains into the Chicago River, carrying, among other things, droppings from birds and other animals.

Second, heavy rains can occasionally overwhelm local sewer systems. These events can cause harmful combined sewer overflow [CSOs] into the Chicago River. These events are reported by the MWRD and other advocacy groups. H2NOW augments the CSO alert system by providing more detailed information about river water quality.