In sub-Saharan Africa, the urban population has doubled since the mid-1990s, and reached 400 million people in 2016. According to experts, 40 percent of the region’s total population resides in cities, compared to 31 percent in 2000. During the next 15 years, the United Nations predicts the world’s 10 fastest-growing cities will be in Africa. However, the development of infrastructure and industries has not kept pace with the growth in urban population. Sixty percent of city dwellers in sub-Saharan Africa live in slums, and only 25 percent have access to safe drinking water. Poor sewage systems and weak flood control present another challenge. Most of Africa’s urban growth is in small and mid-sized cities, with slightly more than half of African urban dwellers living in cities with populations of less than 250,000.