History of water supply and sanitation

The history of water supply and sanitation is one of a logistical challenge to provide clean water and sanitation systems since the dawn of civilization. Where water resources, infrastructure or sanitation systems were insufficient, diseases spread and people fell sick or died prematurely. Major human settlements could initially develop only where fresh surface water was plentiful, such as near rivers or natural springs. Throughout history, people have devised systems to make getting water into their communities and households and disposing of (and later also treating) wastewater more convenient. The historical focus of sewage treatment was on the conveyance of raw sewage to a natural body of water, e.g. a river or ocean, where it would be diluted and dissipated. Early human habitations were often built next to water sources. Rivers would often serve as a crude form of natural sewage disposal. Over the millennia, technology has dramatically increased the distances across which water can be relocated. Furthermore, treatment processes to purify drinking water and to treat wastewater have been improved. During the Neolithic era, humans dug the first permanent water wells, from where vessels could be filled and carried by hand. Wells dug around 6500 BC have been found in the Jezreel Valley. The size of human settlements was largely dependent on nearby available water. A primitive indoor, tree bark lined, two-channel, stone, fresh and wastewater system appears to have featured in the houses of Skara Brae, and the Barnhouse Settlement, from around 3000 BCE, along with a cell-like enclave in a number of houses, of Skara Brae, that it has been suggested may have functioned as an early indoor latrine. Waste water reuse is an ancient practice, which has been applied since the dawn of human history, and is connected to the development of sanitation provision. Reuse of untreated municipal wastewater has been practiced for many centuries with the objective of diverting human waste outside of urban settlements.