News

GRDA Issuing E. coli advisory for areas of Grand, Hudson lakes and Illinois River

May 24, 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, May 23, water samples collected from the following lake and Illinois River areas confirmed the presence of high levels of E. coli:

The public is advised that high levels of E. coli may be present in these areas over the course of the weekend. Levels of E. coli often rise with inflows associated with the significant rainfall events that have recently occurred and are expected to continue in the area through the weekend.

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):

An Oklahoma State Department of Health E. coli Fact Sheet can be found here: Shiga Toxin – Producing E. Coli

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