Widespread construction of sanitary sewers is a comparatively recent technological advance. Most sewerage in the U.S. has been installed after 1960. Even more surprising is the early opposition to sewerage as 'municipal socialism'.
A Brief (Illustrated) History of Human Waste Disposal -- and its possible future.
Part 1. Cesspits & Outhouses
Part 2. Toilets & Water Carriage
Part 3. Sewerage (attached pps)
Part 4. Sewage Treatment
Part 5. Wastewater Treatment
Part 6. The Future: Wastewater Reclamation