According to The United Nations, Kenya is classified as a chronically water scarce country on the basis of having one of the lowest natural water replenishment rates. Kenyans in general do not have adequate sanitation; more than 90 per cent of the water and sanitation related disease outbreaks occur in the rural areas; 50 per cent of rural households have no toilet facilities at all, and where they exist they are generally unhygienic; up to 50 per cent of the urban populations reside in slum environments where sanitation conditions are appalling; on average, schools have only one latrine per 100 pupils compared with the recommended maximum of 40 pupils per latrine; more than three-quarters of Kenya is still vulnerable to disasters, especially floods, droughts and cholera.