5. "Finding water takes most of people's time," said Mathias Diassana, head doctor of the health centre in Koro, 150km from Mopti. "Often women spend more than five hours per day getting water for domestic use" while men spend time gathering water for livestock. There are two traditional wells in Toroli and two water pumps, which have better quality. This water, however, is not free. Purchasing water poses a heavy burden on many Malians, most of whom survive on less than US$2 per day, according to the United Nations. With water so scarce in the 79,000 sq km of the Mopti region, people look for whatever sources they can find. The water table is usually more than 60 meters deep and some water points have dried up altogether because of the drought. As a result people look to water sources that are easier to access. "In this region, there are many places that do not have water points, even some health centres do not have water," said Diassana. "This is why people...are getting water from natural ponds and this is not good - it brings public health problems.“ In the village health center in Koro, Diassana said that diarrhoea is the most common ailment after malaria.