Regional Water -supply at www.japanese-home-gardens.com

When the distance to remote sources m construction too expensive for a single commui to finance, regional water -supply water-supply systems w set up. The earliest in the United States wa: 1895—the Metropolitan Water District of Ma; chusetts, serving Boston and suburban commt ties within 10 miles of the city. It origin; served 18 communities with a population be] 900,000 and now serves 30 communities wit population of 1,600,000. (Consult Hazen, Jc nal of the American Water Works Associati vol. 50, p. 1137, 1958.) Beginnings of Water Treatment.—Of mote antiquity is the appreciation of the relat of the drinking water supply to disease.

Water Supply.—The way in which Rome is supplied with water has several distinctive aspects. No storage reservoirs are necessary since the source of supply is constant. Furthermore, each aqueduct bringing water to the city has separate sources and distribution. Fed by springs at the foothills of the Apennines, by percolation of water through the volcanic ash hills, and by some of the crater lakes, Rome's aqueducts supply all the city's fountains as well as its industrial and domestic needs.

The advent of the atomic bomb has added new contaminating agents. In the event of an atomic bombing, radioactive contamination of the water could arise from four possible sources: fission products of the bomb; reduced activity in the dissolved mineral matter; unfissioned material of which the bomb was made; and contaminated soil blown or washed into the water supply. Radioactive material in water which is deposited in the body may cause changes that may not appear for many years, long after irreparable physical damage has been done. The most common contaminator of water supply is strontium-90 .