The Golden State: Where & How to Live, Secure, Visit, Enjoy and Thrive in California
How To Design And Install Plumbing
Water passes through a very interesting cycle which only the student of science appreciates. The atmosphere which surrounds the earth's surface contains water which varies in amount in direct proportion to the temperature of its gases. Atmosphere which has become saturated with water precipitates its moisture when its temperature lowers. This phenomenon is termed rainfall. The moisture falls to earth and finds its way into a number of reservoirs provided by nature.
Vast depressions in the earth are filled with water through the medium of natural water courses, such as rivers, dry runs, underground water tables, and a gravity flow over the earth's surface. These bodies of water are classified as inland lakes and are ex cellent sources of water. Sometimes the rainfall finds its way into the soil and forms water tables at various levels because of the impervious nature of the undersoil. Often a water table deep in the soil consists of a sand or gravel stratum, which connects or empties into the basin of an inland lake and provides a splendid source of water supply through the medium of a drilled well. Water may be taken from any of these sources for human consumption after it has undergone preliminary treatment to assure its purity.
Water is also evaporated into the atmosphere; and industry and other activities take their share to satisfy the needs of civilization. The original volume is diminished only to be restored however. The atmosphere becomes saturated and drops its water back to earth. Man uses the water for domestic and sanitary purposes and returns it to the source through scientific sewage disposal plants or by natural means. Industry, likewise, replaces water diverted to its uses. Hence, the cycle is completed, but it is of prime importance that the supply be protected against pollution, for once it fouls no one can predict how disastrous may be the results.
Purification of Municipal Water Supply. The plumber does not require knowledge of water correction of an engineering level to work at his trade; but he should have an understanding of the processes of water treatment. This is essential because a realization of the importance of pure water to a community is basic to plumbing practice; and when it is seen to what length municipal administrative agencies go to provide clean water, the plumber will realize how vital to the maintenance of high standards of purity is his own work.
Water taken from its natural sources—the ground, lakes, or rivers—contains many objectionable elements. It may possess gases of an obnoxious nature, bacteria, mineral elements, mud, and suspended vegetable growths which render it unpalatable. Some of these objectionable materials may be eliminated readily, others require complex treatment.
