Sewage System, 600 BC – What could be more important for health!

Unclean drinking water has been the leading cause of human death throughout history.

Given the wide range of diseases that sewage or sewage-contaminated water can cause, the development of effective sewage systems more than deserves a chapter in this book. For example, the following sewage-related diseases are potential hazards in the United States today, and most can cause severe diarrhea: Campylobacteriosis (the most common diarrheal disease in the United States, caused by Campylobacter bacteria, which can spread into the bloodstream and cause a life-threatening infection in people with weakened immune systems), cryptosporidiosis (a disease caused by the microscopic parasite Cryptosporidium parvum), diarrheagenic E. koli (different varieties of Escherichia koli bacteria), encephalitis (inflammation of the brain—a viral disease frequently transmitted when mosquitoes lay eggs in sewage), viral gastroenteritis (caused by many viruses, including rotavirus), giardiasis (caused by the single-celled microscopic parasite Giardia intestinalis), hepatitis A (a liver disease caused by a virus), leptospirosis (caused by bacteria) and methaemoglobinaemia (also known as blue baby syndrome, triggered when babies drink nitrate-rich water from septic-system water).

Other sewage-related diseases include polio (caused by a virus) and the following diseases caused by bacteria: salmonellosis, shigellosis, paratyphoid fever, typhoid fever, yersiniosis and cholera.

Traditionally, the initial construction date of the Cloaca Maxima, one of the world's most famous early large sewage systems, built in ancient Rome to drain local marshes and the canal, is approximately 600 BC. However, ancient sewage drainage systems were built in ancient India, the prehistoric Middle East, Crete and Scotland. Today, sewage treatment generally involves various filters and the biological breakdown of waste by microorganisms in a managed habitat, followed by disinfection to reduce the number of microorganisms before the water is released into the environment. Disinfectants may include chlorine, ultraviolet light and ozone. Chemicals are sometimes used to lower nitrogen and phosphorus levels. Before sewage systems, city residents generally threw their waste into the streets.

Image description: The latrines of Housesteads Roman Fort along Hadrian's Wall in the ancient Roman province of Britannia. Flowing water from adjacent tanks would wash away the waste material.

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