IRON BACTERIA.

Wairarapa Times-Age, 30 April 1940, Page 2

IRON BACTERIA.

EFFECTS IN WATER MAINS CHOKING UP THE BORE. PROBLEM AND ITS SOLUTION. Further observations on the benefits of concrete-lining Masterton's watermains, a lean proposal for which is to ibe submitted to the ratepayers shortly are given below: — Water containing iron bacteria is responsible for the tubereules which threaten to choke-up the bore of metal pipes. The incrustration usually consists of a dark-brown layer, with a number of nodules. Regarding such formation as unavoidable. leading engineers have computed that an allowance of 33 1-3 per cent was needed in the bore of metal pipes to ensure an effective carryjng capacity after incrustration had set in. By the use of cement-lined pipes, however, no allowance is necessary. In order to ascertain the effects of chemical cn cement-lined pipes, they have been subjected to tests with canal, reservoir, and soft or peaty waters, beet sugar effluent waste containing molasses, heavy oils, beer, vinegar, and acetic acid (5 per cent); and, in every case, these have been shown not to have any deleterious effect on the lining. QUESTIONS AND ANSWERS. 25. Q. What about all the swimming baths in the town? —are they not responsible for reducing the town pressure? A. No. Although we have 2 public. 5 school, and 3 private swimming pools drawing ;heir supplies off the borough supply, they are only permitted to be filled or re-filled during high-pressure periods; and, on several occasions, they have remained empty for days at a I time, awaiting authority to re-fill I them. 26. Q. Supposing the major scheme is turned down when the proposal for it is before the ratepayers at some future date, is there anything gained by carrying out the present scheme’? A. Yes. The increase in the flow of water is permanent and the life of the mains considerably prolonged. (To be continued.)