THE VICTORIA CHANNEL.

Otago Daily Times, Issue 10721, 9 February 1897, Page 4

THE VICTORIA CHANNEL.

THE SAND PUMP.

; A visit oE inspection -was made by the j membera of the Harbour Board and of - the Chamber of Commerce yesterday morni ing to the sand pump in the Victoria S channel. The tug Plucky left the Rattray j street wharf at 10 o'clock with the party , on board, which comprised the Chairman ! of the Harbour Board (Mr H. Gourley), Hon. ! D. Pinkerton, Captain M'Kinnon, and Messrs { W. Dawson, "W. Wright, aud J. Robin ; Me i G. L. Denniston (chairman oE the Chamber of j Commefce), and Messrs Jowitt, Henderson, ! Lane, Sligo, Lees, Livingstone, Lethbridge,' T. Brown, J. Stewart, A. C. Begg, representatives of the press, Captain Sl'Callnm (harbour- ; master), and Mr D. G. Stephen?, She board's ' inspector of works. ( The tug soon steamed down to the dredge j Vulcan, which was moored a little above i Burkes, and was all ready for working. Mr j Stephens and the dredgemaster explained the i machinery and its operation. The tube of the I pump is 30ft in length, and is lowered or raised i to suit the work. At Dtessu1; it U dredg- i ing to a depth o£ 17it" at low tide, tha ' intention being to leave a permanent depth of i 16fS. The large engines' iv the hull oi the ! dtedge work the pump, which is a very power- ! ful one, and once suckftd up a grent round roa<-s i of iron—an oid wheei, —which is kept as a 1 curiosity ».t the board's offic?. From this ! suction tuba the material is discharged through pipes'which are carried on five large puut-s und fastened together with flexible cup snd socket joints, and couvey the material a distance of no leas than 45«\ aud these disharge it with great rapidity. When the tide is full the discharge pipe is carried outside the training wall, but at ! times—aud this was the case during yesterday's j visit—the material is discharged on the channel j side of the wall, but close to it, an-i at what is i regarded as an absolutely safe distance—some ; 300ft—from the channel. This is done with the view also of strengthening the wall, by filling up a portion which otherwise is likely to cause trouble. Ac the moutb. of the suction pipe there are two sets of cutters which are worked by means of chain gear connecting with a sepirateengine Sited up on deck nearly amidships. These rotating cutters tear uy everything within reach, and stir the sand and stones so th&fctheymore readilyfind entrance to the pump. The material is very heavy, a sort o£ sandy cement, but this method appears to be success- \ ful in dealing with it. Some trouble is caused | by the deuse growth of sea anemones, and occa- < sionally it 13 necessary to slop to clear them 1 away. The end punt, over which the discharge j pipe projects, is fastened by means of heavy j anchors, and the others form a sort of chain I with the flexible pipe joints as consecliug f links. At; the other end, of course, 13 the dredge j with its pumping machinery and other gear. 1 The dredge i» moved gradually from side to side j of the channel by means of a soparate engine, j anchors, and chaios. As t!he dredge moves away ■ from the wall the chain of uuuts straightens j out, allowing it to reach "right across the ; channel, and then on returning the curve j again forms, to that work continues uu- j interruptedly, the dredge moving and the j point of discharge remaining stationary. The ; sand pump has been kept at wort at the j ch&rmeL fcince the 6»h November, at> such, an ! angle that a depth of 16ft is cleared ; cutting ! sometimes a few inches and at other times feet, j but, of course, securing a uniform depth. Some ! M chains of the chanuel had thus been cleared '■ when soundings were taken on tha 22qi1 of last j month, and now the distance finished is j approximately tiuee-qttailers of a mile. The j pump started at a point on the Dunsdin aide ■ of Ravensbourne, and is working her wav ; down the channel. Prom what has been said j as to the method of working the pump it will ■ be seen that it is often necessary to atop opera- : tions in order to get out of the way of pdsßiug j vessels. The dredge is drawn to Hie side with \ the pump raised, and so it ofteu happens that j she is seen occupied in the apparently useless ] task of pumping clear water into the sea. This > has called forth tome hostile comments, but \ ife is necessary to let vessels pass, and 5 lit is more economical to ketfp the pump i I going discharging water than to stop it j for a short time and to have to create a fresh . • vacuum to resume operations. It is estimated • that the pump will discharge 800 nubic yards of ' solid material each day of eight hours, but the j amount varies according to the nature of the i material and the stoppages that take place. ] Still it is considered that the dredge pump : works satisfactorily, and that good progress j j will now be made with the important -work oE ; j deepening the channel. '. I Soon after the visitors: boarded tha dredge, j the pump was lowered and the machinery set • j going. la a very little time there was a big ! : discharge, lirst of water and then of water ' heavily charged with.material—a thick, dark j fluid, which, when caught,in a bucket, in a few i seconds showed a heavy,, dark deposit. Unfor- i J tunately the pu.np was stopped twice—ones by \ j the chain that worki the. cutters Riving way j ■ and again by a mans of marine growths blockiug ■ ; the pipe, so that the machinery were not seen '. I at wdrk under at »U .favourable conditions. ! j The pipe was previously choked in this manuer ! ! for the first time last, week, and this therefore is j not a frequent cause of delay. We understand j that with 15 percent, of solid matter the dredge i would be uoiag fairly effective work and that j the discharge carries from 10 per cant, to 50 j per cent, of solid material, tae average beiog j ;' quite satisfactory. • j S The Plucky with the visitors returned to town shortly after 12 o'clock. On the way un three brief speeches Wdre made in the cabin. Mr Denniston said he thought it only becoming that he should on behalf of the Chamber of Commerce thank Mr Gourley aad the members of the Harbour Board for the opportunity they bad given them of seeing the new pump at work. It had been very interesting to see the machinery in operation, and ! although they had not had time to witness any I very successful results, owing to ths unforj tunate accident that had occurred, they could i express the hope that not only on account of J the public feeling that had been recently m&ui- ! fested, bub from cheir own sense of duty and of I the importance of the work to Dunedtn the j Harbour Board would lose no opportunity of I prosecuting the york to the utmost of their j ability, and would keep the punt at work as ; steadily as possible. They feit obliged to the board for the opportunity afforded of seeing , the dredge and wnVd the biard all sneeees.— (Applause.) j Mr GbuRLEr s.-.id h.-j wa6 never more out of I place than when speaking without preparation, but on behalf of the board he desired to ' acknowledge the good wishes that had been expressed. He could assure them that every . mamberof the boatd was oniy too anxious to do I all that possibly could be done to improve our i harbour. Every available shilling after current ] espeuses had beea met would bo spent in im- ! proving the harbour, and that was all they j could do. A3 they were aware the current ; expenses were large, and mu6t be met; but j after their engagements had been met they would do all they could and spend all they could ' on the improi'.irnivnt of the Upper and Lower i Harbour. I Mr Denniston -u^iju.itcd that Mr Pinkerton ! might also apmopriatuly say soroOohicg. '■ The Hon. D. Pinkerton said that he very ; heartily endorsed allthat the chairman of the fa >ard had said, and would further remark that-, j he had no sympathy with the cry of " Dnnediu : for Dunediu," or the "Pi>rt for the Port" ; • , the harbour was one, and they should arrange j to get the largest ships to Port Chalmers, and I do the best they could to bring large ones to ; Dunedin. What they did was really not for ! Dunedin or Port Chalmers, but for the advantage of Otago.