WATER Supply of Rural Communities Frequently Requires Purification

Water in rural communities used for drinking and general household purposes is all too frequently excessively hard, highly mineralized with soluble sodium salts, loaded with iron compounds, turbid and cloudy, foul smelling and tasting, or polluted, whereas it should be lightly mineralized, practically free from iron, sparkling clear, and free from objectionable odor and taste and from microorganisms that may endanger health. Although all of the undesirable features enumerated are found in very few rural water supplies, one or more occur in a very large proportion of them. Fortunate indeed is the family possessing an abundant supply of water that is wholly acceptable for general use.

The hardness of water is due chiefly to salts of calcium and magnesium. The hardness that can be removed by boiling is called temporary hardness and that which remains after boiling is called permanent hardness. Temporary hardness is due in large part to limestone or magnesian limestone held in solution by carbon dioxide, and permanent hardness is due in large part to dissolved calcium sulphate or gypsum. Hardness in water is recognized by its harsh “feel,” by the fact that a great deal of soap is required to produce a lather, and by the formation of deposits or incrustations in vessels in which the water is stored or heated. Temporary hardness can be reduced by treatment with minute quantities of limewater, followed by settling and filtering, and permanent hardness can be reduced by treatment with small quantities of washing-soda solution, followed by settling and filtering. These chemicals, however, should not be added by inexperienced persons to water to be used for drinking and they must be added in just the right quantities. As chemical analyses of water, as well as settling tanks, filters, and other equipment, are necessary for this work, it is preferable, when the outlay is warranted, to buy water-softening apparatus, several types of which are found on the market. The names of manufacturers of such apparatus can be obtained from a trade directory. It is usually not deemed practicable to install water softeners in the average rural household because of the expense. If the water is to be used only for cleansing purposes ammonia or borax may be used to soften it.

The only way to render acceptable a water containing an excessively high proportion of sodium chloride, sodium sulphate, or sodium bicarbonate is to distill it. Distillation of water for general household use is generally held to be out of the question because of the expense.

Iron, when present even in small quantities, stains clothes and gives drinking water a very unpalatable appearance, due to the precipitation of the iron as insoluble oxides when the water is heated or allowed to stand. Frequently the iron can be removed by aerating, storing the water in tanks until most of the metal is precipitated, and then filtering. Sometimes, however, the iron is held in solution in organic combinations, and the addition of a very small quantity of limewater is necessary to precipitate it. As already indicated, it is inadvisable to add this or any other chemical if the water is intended for drinking.  Iron-removal apparatus can be bought on the market, but is rather too expensive for the average householder.

Odors of water are described as fishy, aromatic, earthy, musty, rotten egg, etc. Many of these odors are due to microscopic organisms, as, for example, the fishy and oily odor of Uroglena, the aromatic or rose-geranium odor of Asterionella, the ripe-cucumber odor of Synura, and the green-corn odor of Anabaena. Others, such as the pig-pen odor of decaying Anabaena, are due to decomposition of microscopic organisms. A rotten-egg odor is usually due to hydrogen sulphide or other sulphur compounds, and an earthy odor is usually due to organic matter and clay. It is not generally believed that organisms such as Asterionella and Synura are injurious to health, but water containing them is objectionable from an aesthetic standpoint and it is possible that their presence in large numbers may cause temporary intestinal disorders. But odors may be caused by sewage or other pollution, in which case the water may contain pathogenic organisms, making it highly dangerous to health. Frequently filtration through sand or charcoal, or both, will remove or greatly reduce objectionable odors. This treatment, however, can not be depended upon to remove all disease-producing organisms.

There is no way of proving that a water is polluted with disease- producing organisms other than by laboratory analysis or by showing that a particular water supply is the direct cause of illness. Bad odor or taste, a cloudy or turbid appearance of the water after rains, and the development of intestinal disorders after drinking it sometimes indicate a polluted water supply. On the other hand, bad odor is often due to causes other than pollution, and a sparkling clear water may convey disease. Water believed to be polluted should not be used for drinking unless there is no other water available, in which case it should be heated until it boils vigorously. Other emergency methods of rendering polluted water safe for drinking can not be described here because of lack of space. Suspected water should always be analyzed as soon as possible and suitable remedial measures taken if pollution is proved. The United States Department of Agriculture can not analyze water for individuals, and many States are subject to similar restrictions. Specific inquiries regarding pollution of water, analyses, etc., can best be answered by State health officials, who are familiar with local conditions.