Port-au-Prince, Haiti, is one of the largest cities in the world without a central sewage system. There are no sewers connecting sinks, showers and toilets to hulking wastewater treatment plants. Most of the more than 3 million people in the metro area use outhouses, and much of that waste ends up in canals, ditches and other unsanitary dumping grounds where it can contaminate drinking water and spread disease.
Without a sewage system to divert waste out of clogged canals, the Good Friday rainstorm filled the streets and alleys of Project Drouillard with 3 feet of raw sewage. Seven people drowned in the canal. Jean Claude Derlia got an infection that still hasn't gone away.
https://www.npr.org/...sewage-problems