CALLICTION, IMPOUNDING AND DISTRIBUTION OF WATER SUPPLIES.
In the collection, impounding and distribu tion of water for water-supply purposes, a few systems will suffice to illustrate how many operate. As already stated, many communities obtain their supply from ground waters by means of wells and spri.
Batavia in the East Indies, notorious for its unhealthfulness, supplies its 210,000 inhabitants from ordinary wells. Many ground waters are polluted by surface waters.
Amsterdam derives its supply from open canals containing the waters collected from sand dunes and also from the river Vecbt. Such waters are filtered. Antwerp derives its sup ply from polluted river water, which is treated and also filtered.
Rotterdam obtains its supply from Maas (Rhine) is then filtered.
Magdeburg and Altona obtain their sup plies ram whichom the Elbe, which are treated and filtered. Breslau obtains its supply from the Oder, Budapest from the Danube, Petrograd from the Neva, and Warsaw from the Weich sel River. All such raw waters are filtered and some, or all of them, treated with germi cidal disinfectants.
Constantinople obtains its supply from streams, springs and forest catchment areas. where the waters are collected in impounding reservoirs and conducted in aqueducts to the city.
Damascus obtains its supply from the Adana River through conduits, which also convey water for power purposes. See Syria in article on RAINFALL.
Jerusalem obtains its water from springs. cisterns and pools, fed by conduits bringing water from Ain Saleh and other distant springs. Water from the Virgin Fountain flows through a tunnel to the Pool of Siloam.
In Pbcenicia near Tyre were waterworks, consisting of towers, into which the artesian well waters flowed upward to a height of 20 feet or more above ground. Those waters were then conducted into reservoirs for the supply of that ancient port Berlin, Germany, obtains most of its water from deep boreholes near the shores of Lake Tegel, an expansion of the Havel River, and from Lake Muggel, one of the expansions of the Spree. These contain some iron in solu tion, as do most ground waters of Germany. It also obtains part of its supply from wells. since it has succeeded in eliminating iron from its ground waters.
The Spree was said to contain 2.500.000 more bacteria per cubic centimeter below Berlin than it contained above Berlin.
In 1878 ceenothris was found in the raw water of the Spree and in wells ai Char!often burg Dr. Richard Gans' new method and Herr
PoetItt's process were used to eliminate the iron and the bacteria, such as crenothris and odor micro-organisms dependent thereon. There are 60 or more sand filters with an aggregate am of 3S or more acres and other processes need to purify daily 66,000,000 gallons of water winch is pumped into the city. The bacterial reduction in 1900 was from 8% to 27 per cubic centimeter in lAtiggelsee Works and from 345 to 22 per cubic centimeter in the Testier Works. There the death rate from typhoid fever and other diseases traceable to pathogenic bacteria is low. A new testing station of its water supply and is maintained in Berlin. In erha daily consumed 22 gallons for each of its 2.330,000 inhabitants. One of the most extensive plants in !Germany for removing iron from ground water is that at Erlenstegen for removing the iron from the ground water supply of Nuremberg. Munich obtains its water supply chiefly from spring and infiltration gal leries constructed in the layers of sand and gravel in the western slopes of the Alps. Those galleries of concrete in some parts intercept the flow of ground waters. The water so col lected is conducted to the city, which in 1911 consumed daily 57 gallons for each of its 571, Q00 inhabitants.
Hamburg obtained its water from the river Elbe and prior to the epidemic of Asiatic l893 a municipal filtering plant was installed. Later a deferrization plant was also installed there. In 1913 Hamburg daily consumed 37 gallons each of its 977,600 inhabitants. Double fi • -ation is employed in Altona, Bremen and Schi Vienna norms its supply or pure water through masonry-arched aqueducts, whose in terior measurements are 0.84 by 0.93 meters from springs 913 feet and 1,1% feet, respec tively, above sea-level and about 400 feet to 600 feet above distributing reservoirs in the city and from ground waters in the Schneeberg region 59 miles distant in the Alps, and from other springs and the Salza River, 114 miles distant These are gravity systems, hut in the city some pumping is necessary to fill the high est service reservoirs about 550 feet above sea level. Since its introduction and the use of sterilizing agencies typhoid has nearly disap peared. Such Alpine sources, however, are quite devoid of pathogenic bacteria. In 1914 Vienna consumed 25 gallons per day for each of its 2.066,000 inhabitants.