Diarrhea, stomach cramp, high temperature, nausea, headaches and drowsiness are some of the symptoms that can develop after drinking contaminated water. The worst cases can result in kidney failure. The most recent research into private water supplies (Risebro 2012) confirms that over 50% of private water supplies pose a significant health risk. The research identified an incidence of diarrhoea 5 times higher than normal. Children under 10 years old and visitors are most at risk of becoming ill from drinking water from a private water supply. The findings apply equally to springs and boreholes.