94% of the piped water supply for Nairobi comes from rivers and reservoirs in the Aberdare Range north of the city, of which the reservoir of the Thika Dam is the most important one. Water distribution losses – technically called non-revenue water – are 40%, and only 40% of those with house connections receive water continuously. Slum residents receive water through water kiosks and end up paying much higher water prices than those fortunate enough to have access to piped water at their residence.