E. coli has been detected in the tap water at Spokane County Raceway, prompting health officials to advise visitors to use bottled water.
People should not use water at the racetrack for drinking, washing hands or preparing food.
The bacteria, which live in the intestines of people and animals, can produce toxins and make people sick with diarrhea. It was found in an employee bathroom, according to raceway manager Cindy Gibbs.
There have been no confirmed report of illnesses related to E. coli.
The health warning is likely to extend through next week as local officials decontaminate the water supply.
Raceway participants and fans may buy bottled water and food on the premises, or bring their own beverages, according to a press release.
Hand sanitizers will be provided.