DS went for his swimming lesson after school today and during the lesson another kid threw up at the side of the pool. One of the pool attendants then spent about 20 minutes scooping water out of the pool over the pile of sick so it could wash down the drainage grates. Surely this would then flow back into the pool through the filter system, where all the other kids were still swimming. I don't know whether to complain to whoever manages the pool about the obvious health risks. DP says I'm over-reacting.