News

GRDA issuing E. coli advisory for areas of Hudson Lake and the Illinois River

Jun 20, 2025

Due to elevated levels of E. coli, resulting from recent heavy rains and water flows, the Grand River Dam Authority is issuing an advisory for several areas of the waters under its control.

On Friday, June 20, water samples collected from Lake Hudson and the Illinois River areas confirmed the presence of high levels of E. coli:

The public is advised that high levels of E. coli above the state advisory level (235 mpn/100ml) may be present in these areas over the course of the weekend. Levels of E. coli often rise with inflows associated with significant rainfall events that have recently occurred and are expected to continue in the area throughout the weekend.

According to the Oklahoma State Department of Health, E. coli are bacteria found in the environment, foods, and intestines of people and animals. E. coli is a large and diverse group of bacteria. Although most strains are harmless, others can make you sick. Some kinds of E. coli can cause diarrhea, while others cause urinary tract infections, respiratory illness and pneumonia, and other illnesses.

Additionally, GRDA encourages the public to practice common sense in the water and follow safe swimming practices, no matter which waters you plan to visit.

Those safe practices include several swimming tips from the Oklahoma Department of Environmental Quality (ODEQ):

The GRDA Ecosystem and Watershed Management Department will continue to monitor the situation and provide updates, and any future advisories as needed.