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From the History of Water Supply and Water DisposalThe history of water supply extends over several millennia. Sites excavated in the Indus Valley and in Punjab show that bathrooms and drains were common in Indian cities 4 millennia ago. Streets were drained by covered sewers 2 ft. deep and made of moulded (сделанный по шаблону) bricks cemented with a mortar of mud. Even two millennia BC, the Greeks and Egyptians had adequate supplies of drinking water for their cities, drained streets, had bathrooms in their houses, and, in Crete, water flushing arrangements (устройство для слива воды) for toilets. The Incas also had impressive sewerage systems and baths. The first aqueducts in the form of tunnels originated in ancient Persia (Iran) probably as early as the fourth millennium B. C. Their purpose was to bring water from the foothills of the northern mountains to the southern plains region for irrigation and domestic use. Stone pipes were very early preferred for small quantities of water and for drains. Such pipes were used in the Indus cities before 1500 B. C. As sanitary engineers, the Romans set a great example and left their mark in history. A public water supply was considered a basic essential of civic life. They had well-developed water supply systems, and their standards of engineering sanitation were not matched again in Europe and North America until the 19 th century. Studies show that Rome's water supply exceeded 40 gallons per head per day, and was supplied to public baths, fountains and other public structures, as well as private houses. At their peak they were able to provide an estimated 300 gallons per head per day. Their aqueducts and cisterns (цистерны) can be seen all over Europe, and were frequently (часто) copied in medieval times. In medieval Europe, the most urgent (крайне необходимый) task was also to provide an adequate supply of good water, using cisterns, natural springs, and dug wells, practices still of course in use today in undeveloped areas. Stone water courses (курс, ход), aqueducts, and wooden pipes were used there in the 13 th century. Lead pipes were used only in the 15 th century. Usually, pipes carried water to cisterns in the town at street intersections. A constant problem was separation of wastes from the water supply that was why from the 14th century strong city regulations controlled cesspools in the streets and elsewhere were adopted. Developments were similar in North America. But the Roman’s idea of publicly-owned water and sanitary systems did not come into effect here until about the mid-19 th century. Even the construction of water supply systems in the U. S. dates from 1754. In Russia a water conduit made of wooden pipes, whose construction dates to the turn of the 12 th century, was discovered during excavations in Novgorod. There is also information concerning a gravitational-flow water conduit made of earthenware pipes that was constructed in Georgia in the 13 th century. In the 15 th century a spring-fed water pipeline system was constructed for the Moscow Kremlin. The water-main systems in St. Petersburg, Peterhof, and Tsarskoe Selo were built in the first half of the 18 th century. The installation of the first Moscow (Mytishchi) water conduit was completed in 1804, and the St. Petersburg municipal water-main system was completed in 1861. In 1902 a new Moscow water conduit was put into operation, with a water intake from the Moskva River near the village of Rublevo. A total of 215 cities in pre-Revolutionary Russia (about 20 percent of all cities) had centralized water-supply systems. During the years of Soviet power, water supply has been greatly developed, both in the number of water conduits and the length of water mains and in the amount of water supplied to the public and other consumers. By 1968 there were 1,600 cities and 2,520 workers’ settlements with centralized water supply, the length of water mains had increased by a factor of 34, and the total amount of water supplied through municipal water pipelines had increased by a factor of approximately 40.
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