Bolton to find it covered in fast food and litter in recent weeks, says one frustrated dog walker.Craig Parkinson says he has spent tens of hours filling trolleys full of rubbish left at the reservoir, visiting every morning for the last few weeks.Burgers, barbecues, balloons and lilos have all been among his collections said Mr Parkinson, begging people to take home their litter for the safety of wildlife and passing dogs.He told the Manchester Evening News: "Every morning there are dog walkers