Municipal Wastewater Treatment at Ancient Times...

Methods of waste disposal date from ancient times, and sanitary sewers have been found in the ruins of the prehistoric cities of Crete and the ancient Assyrian cities. Storm-water sewers built by the Romans are still in service today. Although the primary function of these was drainage, the Roman practice of dumping refuse in the streets caused significant quantities of organic matter to be carried along with the rainwater runoff.

Left is the picture of a Roman fort ruins on Hadrian's Wall where water was used to carry human wastes out of the latrines. The second picture (right) is the outfall from a Scottish castle which is just straight down and out from the bathroom. Toward the end of the Middle Ages, below-ground privy vaults and, later, cesspools were developed. When these containers became full, sanitation workers removed the deposit at the owner's expense. The wastes were used as fertilizer at nearby farms or were dumped into watercourses or onto vacant land.

Historical Development in the US...

Below is a picture of a twin latrine in an old mining town (Garnet Montana, USA).

A few centuries later, there was renewed construction of storm sewers, mostly in the form of open channels or street gutters. At first, disposing of any waste in these sewers was forbidden, but by the 19th century it was recognized that community health could be improved by discharging human waste into the storm sewers for rapid removal. Development of municipal water-supply systems and household plumbing brought about flush toilets and the beginning of modern sewer systems. Despite reservations that sanitary sewer systems wasted resources, posed health hazards, and were expensive, many cities built them ; by 1910 there were about 25,000 miles of sewer lines in the United States.

At the beginning of the 20^th century, a few cities and industries began to recognize that the discharge of sewage directly into the streams caused health problems, and this led to the construction of sewage-treatment facilities. At about the same time, the septic tank was introduced as a means of treating domestic sewage from individual households both in suburban and rural areas. Because of the abundance of diluting water and the presence of sizable social and economic problems during the first half of the 20^th century, few municipalities and industries provided wastewater treatment.

During the 1950s and 1960s, the U.S. government encouraged the prevention of pollution by providing funds for the construction of municipal waste-treatment plants, water-pollution research, and technical training and assistance. New processes were developed to treat sewage, analyze wastewater, and evaluate the effects of pollution on the environment. In spite of these efforts, however, expanding population and industrial and economic growth caused the pollution and health difficulties to increase.

In response to the need to make a coordinated effort to protect the environment, the National Environmental Policy Act (NEPA) was signed into law on January 1, 1970. In December of that year, a new independent body, the Environmental Protection Agency (EPA) was created to bring under one roof all of the pollution-control programs related to air, water, and solid wastes. In 1972 the Water Pollution Control Act Amendments expanded the role of the federal government in water pollution control and significantly increased federal funding for construction of waste-treatment works. Congress has also created regulatory mechanisms and established uniform effluent standards.