THE PALMERSTON SEWERAGE SCHEME.

Manawatu Times, Volume LXIV, Issue 280, 4 December 1907, Page 5

THE PALMERSTON SEWERAGE SCHEME.

VISIT TO THE SEPTIC TANKS

Yesterday afternoon his Worship the Mayor accompanied by Dr Freugley, District Health Officer, and Dr Martin, paid a visit to the septic tanks at Awapuui. The party included Crs Stubbs, Holben. Mathieson, Luxford, Bennett, Clausen, and

the Borough engineer, Mr Jickell.

It was a delightful afternoon and the rich fields sparkled in the sunshine. On arriving at the septic tank there was furnished a magnificent object lesson of what sanitary science has accomplished in the disposal of 6ewage. THE TANK.

The tank (the largest in the southern hemisphere) lies in an artificial hollow in order to take advantage of the gravitation and the outfall,and no one on the other side of the grassy banks could possibly imagine that iv few yards away was accumulated the sewage of a large borough. Absolutely no odour was perceptible and even when the bank was crossed and the visitors stood on the concrete ramparts of the tank itself, only the faintest odour could be experienced and this was wholly unobjectionable.

The system of the modern septic tank is one of the marvels of nature and science. The principle is that the sewage enters at one end where the dessicated matter forms an odourless cake, the surface of which is sometimes covered with vegetation. Beneath the shelter of the cake there work in the darkness friendly microbes, eternally busy in dessicating and digesting the solids. It is a perfect hive of benificent bacterial industry. The successive concrete dividing compartments are so arranged that there is an unbroken flow, for instance if it passes through highly placed pipes in one it passes through low ones in the next, and a series of hanging board screens reaching different depths further assi-t the breaking up process. In each of these compartments the appropriate microbe is at work and each leaves the sewage in a better condition than it found it, until it passes out on to the great shingle filter beds with their 504 corrugated iron filter sheets above the shingle, each sheet containing 712 tack holes with a separate tack in to direct the now clean and fluid sewage water to the five feet of shingle below. As the fluid passes through these filters it appears clean and clear, and the final effluent is bright and soarkling and quite odourless.

Under the old system of the sewerage farm there were inevitably offensive odours, however profitable the farm may have been from a producing viewpoint. But so well has the septic tank been developed with its friendly bacteria exercising their at the successive stages that so far as offence is concerned the tank itself might bo in the Square, and, if there were n green hedge around it no one would be aware of the fact. In fact we have come across more odour in passing certain premises on certain streets of Palmerston than this septic tank could ever produce.

His Worship the Mayor, Mr Jickell, and Mr Heatley, who is in charge of the tanks, showed Drs tf'rengley and Martin over them, and Dr Fre-gley expressed himself as more than pleased with the conditions revealed, while Dr Martin who had not previously seen the septic tank expressed great satisfaction with it and considered it was a remarkable triumph in the treatment of sewage.

ON THE RIVER-BED. Or. Stabb3 took a portion of the party farther to show the changes effected in the river and what should he done to protect the tank. But a short time ago the river was running close under the hank within a few yards practically of the tank, and had it continued on this coarse might have endangered that work. Now it is half a mile away from the tank and much of the change lias probably been effected by the willows planted with a view to protection which are now forming a jungle. There is an obvious necessity to connect the willow plantation with the willow clumps higher up the river, and once this were done and a sufficiently broad and thick belt of willows established, into which cattle would not be allowed to trespass, the valuable sewage works might be regarded as humanly safe.

THE ABBATOIRS. From the septic tank the party visited the abbatoirs and were shown over by Mr Carter. Here they were struck by the general cleanliness and absence of odour; the day's killing was over; the sides of beef .and mutton and the dressed pigs hang cleanly on their hooks, and the not too well levelled cement floor had been sluiced down and was being washed with the running water which runs all night. On one of the sheep evidence of vigilance on the part of the meat inspector was given, a cut having been mads into a poiut which he considered suspicious, in order to ascertain whether there was any blemish there, and finding none he had let tue sheep pass. All meat condemned is passed at once into the groat iron digestors, where with the offal and bones, it is treated with, superheated steam tinder a pressure of 40 until everything is thoroughly digested and the bones are reduced to such an extent that they crumble readily underfoot. From this digester the mass is passed to the hydraulic extractor, which is on the principle of a cream separator and by which all moisture is extracted and carried away. Thence the mass passes into the "scrubber" or drier—a great oven with revolving machinery within. After this treatment an elevator on the endless belt and bucket principle carries it up to the upper storey where evervtliing passed into the bone meal is ground fine and goes down again into the bags a valuable blood and bone manure.

lii all the various departments of the abbatoirs everything was found to be clean and satisfactory, the one difficulty of all abbatoirs —that of securing flooring for the pens which will be at once capable of being thoroughly washed down and not be slippery—is felt here, when in passing through the cattle pens, wherein are the cattle awaiting kililng to-morrow, the wild things slipped as they tried to run around their pens to get away from the visitors. That however is a matter which no abbatoirs have yet been able to overcome. The hose and brooms, and perhaps lime waih, might be used oftener in these pens, but judging from what the party saw, Palmerston lias good reason to congratulate itself on the conditions under which its stock is

treated, and the living beasts are converted into the chou and steak of commerce.

Tr Frengley was apparently well satisfied with what he saw, his sole criticism biong on the advisability of a bath-room for the employees such as the award asked for proposes; should be given in creameries, and we are certainly of opinion that in all such establishments there should be a shower-bath room with hot water available, in the interest of cleanliness and the health of the employees.

There is at the abbatoirs a washing room and also a large wooden tub which the men use for washing, but the demands of hygiene call for even more than this, add there is lio doubt whatever that the suggestion has only to be made to the directors to be carried out.