DRAINAGE MATTERS.

Otago Daily Times, Issue 12600, 2 March 1903, Page 2

DRAINAGE MATTERS.

| INTERVIEW WITH MR CUTLER. , Mr A. E, Cutler, one of tho consulting engineers to whom tho Drainage Board haa agreed to refer its engineer's proposals for tho sewerage of the Duaedin drainage area, arrived in town yesterday by tho eteamer Warrimoo. Mr Cutler is principal assistant engineer of the New .South Wales Water Supply and Sewerage Department, which includes tho control of all the water conservation of the State, and has for the past nine years had all the designings of, and been directly responsible under tho prinoipal engineer for carrying out,, tho sewerage works im Sydney*. "You could not," Mr, Cutler said,'in conversation with a representative of the. Daily Unnes who interviewed him on his arrival, _ find a batter training, school than Sydney m regard to sowago problems. This is on: account of the great variety of work that has had to be undertaken as a result of the natural features of tho country. There are low levels and high levels, and isolated areas requiring separate systems of "their own with treatment works attached. In Marriekvillc, a large outlying district, it has been possible to drain to one point and there put in pumping engines, lifting the whole into gravitation sewers; but such a scheme is not possible on the foreshores of tho harbour proper, inasmuch as tho area, although of very great extent, is a long, narrow fringe, it impracticable to drain to cine point, and various small pumping stations have had to bo introduced. Some required to be treated on the, Shone principle, but the major portion had to bo treated by pumps electrically driven. Of these there are 20 stations, and tho majority ! are now completed and in work." Has tho result been satisfactory? "Everything wo have tackled has, to use tho slang phrase, ' turned up trumps.' Tlie ' septic tanks have absolutely surpassed all anticipations. The first portion of the installation of tho metropolitan area has been in use for five years and the latest for itbout three years. The purification is complete: the water is drinkable and has been drunk— if it were compared with the' water in a bottle 011 the table, you could not tell the difference between the cine and the other. When you reflect that you could put the whole of the works big enough for 1000 people in an area of 80ft by 100 ft, and get tho results I have described, you can see what a very important consideration'it is whore you are compelled to put in some system of treatment works and can obtain only a. comparatively email tirea. Where land is valuablo, indeed, it is impossible, without loading up the scheme unnecessarily, to deal with sewage in any other way._ In one of the areas in the Sydney ' district tho separate system haa been carried out, and in some other areas a partial separate system is employed. Whero pumping lias to be resorted to'or treatment works introduced, there e:m bo'very little doubb that the separate system is tho best. As far as sewage problems are concernW, however, no man can go anywhere with preconceived notions of the system-that should bo used there. He has to go imto the wholo problem, from the financial and from tlio engineering standpoint, from beginning to end, beforo ho can state what he thinks the system is that should be adopted, and "oven then it will probably be found that there will bo critios to say that if some other system wore used it would 'be better. Drainage is different from all other engineering works in this respect. In' the case of a water supply schomc, for example, it is in many instances obvious where the supply is to be obtained and what the 6cope of the work should be;, but I do mot think there is any drainage system I have had to do with which might not have been dealt with in two or three different ways in addition to that which was adopted." Tlio question was put to Jlr Cutler as to his views respecting tho merits of concrete for sewer construction purposes. " Concrete haa been used very extensively in Sydney," he said, "for many years. Monier work hao been used to a largo extent lately, but ever sinco the inception of the Sydney system concrete has been used very largely,' and as tho work progressed it was used more and more. Brickwork was also a great deal used, but it was expensive, and it has been found that concrete stands j equally as well as it, if .not,bettor."