Goats were grazing on a patch of grass littered with plastic garbage when Phylis Mueni passed by. She carried three 20-liter jerrycans that once held vegetable oil, one a bright yellow that matched her oversize T-shirt. Everything else was a wash of browns and reds—the rusted metal of corrugated roofing, the labyrinth of mud houses, the drainage ditch that ran along the gullied path. Mueni is a resident of Korogocho (which means “shoulder-to-shoulder” in Swahili) one of Nairobi’s largest and roughest slums. She was in pursuit of a most basic element: water. No one in places like this has running water. On a good day, locals travel 300 feet to fill up their cans for a few cents. On shortage days, which happen about once a week, the search can take most of the day, and people can end up paying six times the usual price.