With cesspools overflows, failure of proper drainage and the contamination of drinking water, epidemics and lingering illnesses became common.
Such conditions are vividly described in the following account from 1849, when workers entering to examine cesspools with oil lamps triggered sudden blasts: In 1847, the first official report on sewerage and drainage by the engineer John Phillips, contained the following description, which portrayed a typical situation of the time: Combined- Versus Separate-Sewer Systems Although sanitary wastes were a constant input to European sewer systems, designs did not anticipate this component until 1843 in Hamburg.
When the water closet came into general use in the mid-19th century, existing privy vaults and cesspools became overwhelmed.
Eventually, this led to the permitted discharge of sanitary wastes into sewers previously restricted to surface runoff only, legally creating combined wastewater.
The permitted discharge of sanitary wastes did not occur in London until 1847 (Kirby and Laurson 1932) or in Paris until 1880 (Reid 1991).