HEALTH NOTES.

Hawera Star, Volume XLVII, 16 November 1927, Page 4

HEALTH NOTES.

GOOD WATER FOR COFNTRY FLUMES. (Uunti.hu ted- by the Department of tiealtn). liie resident in a borough is only ,Siy cvoasionaily icouiieu to give aio ..nought to tiio iiouoeuoid water supply, as me pro-mem $. securing and supplying Ui good wa-te. has been taken over by tlie- local authority. File country resident, however, is in a. different position, as he has to face and solve his own difficulties with regai.d in his water supply. Ln many cases dependence! iias to he placed on tanks; 1.11 other cases wells have to be sunk; in still others a natural spring may be used, and some few may trap -a. natural. Watercourse or stream, in each of these different cases, different difficulties arise; different precautions should be taken and it is now proposed very briefly to discuss these' questions. File collection of rain ■water is perhaps the most common method of securing «i water supply for a country household. Fhe collecting surface is usually the roof. ft is rare in the country t-» use specially prepared areas to collect rainwater. Fhe amount of rainwater collected, depends of course, on two factors : (1) File area of the collecting surface, and (2) the amount of rainfall. Roofs of houses are usually polluted with dust, dropping of birds, leaves- ol’ trees, etc., and it is therefore advisable to allow the first of the rain to- run to- waste. This washes the roof and so ensures- a cleaner and purer water. There are various simple contrivances called “rain water separators which allows the first part of the fall to nin to waste and then automatically divert the remainder of the- rainfall into the. collecting tank.

It is, of course, necessary to- see that ail spoutings and gutters are kept in a- cleanly state. The best storage tank is one of concrete with a smooth inner surface of cement-plaster. Rain water readily attacks metal surfaces and therefore iron tanks are not so acceptable. In addition, nq- lead pipes should be used in connection with, a- water system depending on rainfall. Rain water can readily dissolve lead. Owing to- the fact that it is very soft, rain water is very useful for laundry and cooking purposes. If the ordinary household supply is “hard” it is an economy to save rain water for use in. the laundry. Rain water in the country is usua-llly very pure, but this statement does not hold with regard to rain water collected : n towns, where the atmospheric pollution is much greater. As the rain descends it washes the air and collects the impurities such as dust, smoke, bacteria, that may be floating in the atmosphere. SHALLOW AND DEEP WELLS,

Wei Is are technically known as “shallow” or ‘bleep” wells. With the latter may be included what are known as “artesian” wells. Although depth may have some bearing upon this classification, the question of the ground strata from and. through which the water is drawn is of more importance. With the exception of such as flows off the surface into- rivers, streams, and lakes, all water deposited on the earth’s surface by rainfall, which is not. evaporated, sinks into the ground and subject to the varying permeability of the soil and the subsoil strata, -finds its way to varying depths in the earth and obeys the natural law of gravity by seeking a lower level. There are thus what may be termed “underground streams,” the depth of which are determined by the perviousness or imperviousuess of the subsoil strata they have met in thei.r passage through the earth’s surface. Water which has fo-u.nd its way through the easily permeable strata of the subsoil, but lias been arrested in its downward progress by an impervo-us- stratum is drawn, upon by what are termed “shallow wells.” Such water from its liability to pollution by the organic matter which it may have taken up from the ground upon which it has fallen or through which it lia-s peroo-lated is of doubtful quality for domestic purposes, and may even be dangerous to health, if such pollution is- excreta 1 in origin. Shallow well water can, therefore, never be advocated as a- “safe” supply but where its use is unavoidable, owing to the absence of any better supply, steps. must be taken to obviate its pollution- and particularly its pollution by organic matter of an excreta! nature. No- such well should be driven o-r sunk at a- less distance than IdO feet from any privy, urinal, sewage- tank, or cesspool, pigstye, stable, or cowbail. Neither should it be sunk in heavily manured country, particularly land polluted with ill ght soil. All nightsoil should be buried well away from its vicinity, and house drainage- should be carried in a- direction away from such well. Sanitary conveniences, farm buildings, stables, etc., should be situated where the subsoil water is flowing away from the well. PROTECTION FROM THE WELL. Protection, from surface washings should be affoided by covering the head of the well with a- dome-shaped cover of cement concrete of some wheat greater area than the well-head, provided with openings l'tw the pipe mam, and access to clean the well. Fhe sides from top to- bottom should be protected by a lining of impervious material such as glazed- earthenware, with cement joints, or cement concrete, or brick in mortar with a backing of stiff clay. If any -reasonable suspicion of the water is entertained it should be boiled before use for potable purposes. Shallow well waters are usually fairly soft and of good use economically for laundry purposes. On the other hand, deep well waters are fairly hard, well aerated, and pure, owing to their having taken up much mineral matter into solution during the’ lengthier percolation, with its resultant greater filtration, they have undergone. It is usually only necessary to protect such supplies from actual pollution at the source of supply and to ensure that from the surface clown to the impervious stratum, front the. underside of which they are drawn, no surface or shallow water gains access. This may be effected by ensuring tight joints in any pipes through which the water is drawn or flows by -hydrostatic pressure to the surface in pipe wells -and by lining the well, down to the impervious statum a-s wa,s previously set out in dealing with the shallow well. «,

WATER SUPPLY FROM SPRINGS

Where the water supply is dependent on natural springs the same precautions as regard to prevention of pollution should be taken ns in the ease of wells. In addition the area round the spring should be securely fenced off so as to prevent the access of cattle and other animals. The overflow from the spring should be piped away sr considerable distance so that the surrounding ground is kept as dry as possible. In any case where a sprrng is used for a

water supply an adequate chemical analysis should be made before the water Ls used for household purposes. Many springs which supply a clear, sparkling water show evidence on examination cf serious and recent pollution.