ROOF WATER

Gisborne Times, Volume LXXIII, Issue 11538, 15 January 1932, Page 5

ROOF WATER

NO DANGER FROM ZINC! AND LEAD

DNCLEANED TANKS MORE LIABLE TO CAUSE HARM

MEDICAL HEALTH OFFICER’S SUGGESTION

That there is any danger to health through zinc or load from roofs running • into the household tank is discredited by -tho Medical Officer of Health, Dr. H. B. Turbott,, who states that'he has known no sickness ,in the district duo to such a cause. There is,'however, more danger he states, in using water for drinking frdm an uncleaned tank, and ho urges such receptacles should bo cleaned at least twice a year.. Hhc drought in this district has naturally caused an unusual run on tanks for domestic water supply, and in scores of cases , the tank supply is the only one available for drinking water, This means had t<* be resorted to in these * cases last peason, hut sometimes it is three or four years since tank water was used for purposes other than washing:. In a northern newspaper a correspondent stated recently that tank water is liablo to become impregnate ed with lead- or zinc from the roofs end that those who use it are, therefore, in some danger of poisoning. The correspondent'alleged that cases of sickness in the Gisborne district had been traced to this course.

This statement was placed yesterday by a Times reporter before Dr. Turbott, and his Teply was very reassuring. He said he bad never heard of the alleged eases in Gisborne, and such a matter -would naturally have been referred to him. In theory it was within the bounds of possibility that. tank water might, contain lead or zinc in quantities sufficient, to be dangerous, but in actual practico this was not the case. In the human body there is normally present a Certain percentage of load and zinc, and it is only when that.'' percentage (is exceeded that harm results. An official. standard is laid down for water, and under that standard the following amounts of harmful matters must not he exceeded: Iron, one quarter of a grain to the gallon; lead, one-twentieth of a grr-ay'n; and ziine, .one-tenth of a grain; and zince, one-tenth of a ; grain. That is the maximum amount of metals allowed in drinking water, but according to official tests there is no evidence that more than the above quantities would bo harmful. The ordinary household tank water running from the typical iron roof does not get these quantities, and it may be taken for granted that the rain water in the tanks in Gisborne is quite safe. * During the past few years, said Dr. Turbott, he had received reports of only two cases of sickness allegedly caused through water, and in only one ease could the water, he blamed. Here the sickness was due to the fact that the tank hacl not been cleaned for years. There was more danger from this source than from the iron and zinc on the roof. Where -water is used for drinking pur poses, said the doctor, the tank should ho cleaned at least twice a year, and even on more occasions.

ADVICE TO HOUSEHOLDERS This matter,' commented Dr. Turbott, is perhaps not altogether due to carelessness or to laziness. The great factor is the inconvenience in connection with the tank in present use. The man-hole is fifteen inches in circumference. The householder has to be very slim to enter through this aperture, but perhaps could persuade the small boy of the family to do the work. However, onco Inside, all the dirt, leaves, etc., have to be cleaned up, and then passed up again through the manhole, a very laborious task indeed. Surely, it would be better for, the householder when ordering a tank, to insist on having a cleaning ' plug at the bottom. With this accessory, which can be added at a ridiculously small cost, no trouble is involved. Ihe cleaning plug is unscrewed whenever desired, and all the solid matter run out. He strongly commended tins idea to those who continuously used tank water for drinking purposes. When rain was used only for washing the position was not so impor - ant. Rain water is good water, continued Dr. Turbott. Before it roaches th« tank, however, it runs throng tb'ijNspouting on the roof top, gathers up all the refuse there and deposits \it in the tank. After a prolonged spell of dry weather, the water in • the tank gets lower and lower, until; in the end of course it runs dry.” In the last few days, especially the hot sun, the little water m the tank and the sediment, perhaps the accumulation of years, certainly do not tend to make the water ideal for drinking; in£ fact, nnder such cases, it might prove harmful.

A WATER SEPARATOR Perhaps the best (precaution for householders who regularly use tank water for drinking, continued the doctor, is the installation of a water separator. This is a very simple device and can be made by any plumber.' Briefly, the separator catches the first washing from the roof after a downpour of rain, and allows 1 run away without entering t e an • The separator, however, is more costly than the cleaning plug, and even with its installation the tanks should be kept cleaned at least twice a year. •. CLEANING PLUGS INEXPENSIVE ■ The suggestion- of the Medical Health Officer in regard to a cleaning -.plug was put to a proimnem plumber yesterday, who stated that in his- opinion, Dr. Turbott had touched‘ on a very important subject. His firm\ specialised in tank-making and tank repairs, and in some cases tho dirt and dust found accumulated at the bottom of tanks was surpris-

(Continued from previous column)

ing, oven to experienced workmen. Leaves, and even more solid rubbish, are caught in the spouting and find their way into the tank. Several institutions have cleaning plugs in their tanks, but the householder should use the system to a greater extent. That this was not the. case was all the more inexplicable tv-hen. it could be stated that the cost of such-a plug was only 7/6. With the cleaning plug, there is no need to enter the tank for cleaning purposes. All that is necessary is to Open the plug, and sluice, rinse, or hose the inside of the tank. The universal use of the cleaning plug would make the work of the plumber much more satisfactory, for then there would be fewer complaints as to the trouble involved to the householder in cleaning out a tank.