Harry Potter star Emma Watson, pictured, was taken ill while filming for the film Noah after drinking stagnant water.

The actor, who went to the Dragon School in Oxford, is reported to have said she was left “tired and delirious” from dehydration after director Darren Aronofsky banned water bottles on the set of the Biblical epic.

Watson told Wonderland magazine: “I picked up a mug from my trailer and drank some stagnant water. I was so ill.”