HARBOR EXTENSION.

Taranaki Daily News, Volume L, Issue 59, 18 May 1907, Page 3

HARBOR EXTENSION.

J THE ENGINEER'S REPORT. The extension of the New Plymouth breakwater has nearly exhausted the ' Harbor Board's quarry, and the Board is now looking round for further supplies of stoue. Ml-. F. W. Marchant, the > .-liiisultiiig engineer, reported yesterday on the, proposal to work present quarry below sea-level. Mr. Marchant slated that when at New Plymouth he had looked into the matter, it would be necessary to construct a rubble-stone embankment to a height of 12 foot above high-water mar!;; and. owing to the fierce sea which breakin during storms such embankment would have to be a regular little breakwater. On the ground lie estimated the cost of .M.-s embankment at £4OOO, but he now believed it would cost nearer (MOOD. No material other than rubble would withstand the shocks and tremors caused by blasting operation'.. it was one thing to quarry stoic whore a free and open lace existed, giving to the explosive the best passible yield of stone of which it was capable and quite another to excavate ston • lnblasting from what would be practically a huge shaft. So I hat it was certain that every cubic yard obtained below the present level would cost a great ileal more for quarrying than it had hitherto done. It would be necessary to establish a steam pumping plant to keep the

excavation free from water, and during a heavy sea the whole thing would/ be flooded out by percolation through the embankment. Great loss of time would be thus occasioned,.and a good deal of expense in pumping out the enclosure. He thought the Board should lose no time in testing the western side of Paritutu and the island adjoining, so that they might form -an opinion of the class of stone available there. If the tests showed that stone fit for use in concrete work could be obtained there, well and good; but if not—and he was not at all sanguine about it—then the Board would be brought face to face with a difficulty. The only solution lie was at present able to suggest was that if it were ascertained that the Paritutu and island stone was not fit for use in concrete, then he thought the Board should immediately cease quarrying large rubble in the present quarry and conserve the whole of the stone in it for concrete work, using the best rubble yielded by the Fishi'ag Rock and other places and depositing a larger proportion of concrete blocks in the breakwater. It had been suggested to him some years ago that the Board should lay a line of railway westwards along the beach, and by means of powerful cranes heave out the largest boulders for use as rubble and collect the smaller stuff for concrete work. He had never looked into the matter, but there was nothing impossible about it. It was all a question of cost and sufficiency. One thing, said Mr. Marchant, was certain—that

they had reached a point in the progress of the work where a good deal of circumspection was necessary so that no deadlock might occur later on. Ho. did not anticipate any shortage of useful nibble up to a moderate weight, but he did foresee possible difficulties about the supply of stone suitable for use in concrete work. These difficulties would be overcome in some way, but until the tests had been made he" hart nothing really to work upon. In a supplementary report, Mr. Marchant suggested the possiblity of arranging with the Railway Department for a supply of either spalls or broken metal from the Mount Kgmont quarry now being opened. No doubt such material would be expensive at per yard, but on the other hand there would be no outlay, or very little outlay, in plant or tools. He recommended the Hoard to get into communication with the Department in the matter. Discussing the renort.

Mr. Maxwell said ths in 1!)01 the Railway Department had obtained, permission to take 10,000 yards of stono from the Board's quarry for reclamation work at New Plymouth railway yard. They had exceeded that amount by 25.000 yards, and a deputation pointed this out to the Minister of Railways and the General Manager, and also complained that big blocks of stone were being unnecessarily broken up. The Minister then mentioned the possibility of there being established a quarry on Mt. Kgmont, tapped by a light line of railway, and made a promise that the stone might be returned from that quarry. The secretary read the minutes of March, 11)01, and the New Zealand Times report of the deputation, recording the promise. Eventually it was decided that the chairman and Mr. Maxwell, accompanied if possible by the engineer, should wait upon the Acting-Premier (Minister for Railways), and represent the matter to him, and ask for the, fulfilment of the promise. On the motion of Messrs. Connett and Ward, it was decided to request the engineer, if he can supply the foreman with the necessary working plans for the proposed drives. FOREMAN'S REPORT. The foreman, Mr. F. Henderson, reported that eighteen concrete blocks had been made during the month, DOS tons of stone had been tipped over the end of the breakwater, and one section of 12 feet completed. The total length of the extension was now 282 feci, and there were 80 blocks on land. At the wharf some repairs had been effected, ineluding the completion of the re-deck-ing of the sidewalk. There were three more piles to drive in the wharf, and then a start would be made with the widening for a further length of 170 feet. Timber for wharf widening had arrived. The squared beams were a good lot, but some of the piles were, smaller than specilied. Some of the 65 feet piles could only lie classed as 50 fei't, others as only 45 feet. The diver had been down on six days at the new berth, removing surface boulders. In all ten tons had been brought up, and there was still a large pateh of eonglomerate reef lo be removed at the shore end. This might have to be bored and the charges of gelatine placed in the holes, as surface explosions did not seem to have much effect. Twenty-two of the piles for wharf extension were not up to specified size. Regarding the measurements of the piles, the works committee made a recommendation that (lie faulty timber lie condemned. Mr. King moved and Mr. McLean seconded that the contractor he notified that the timber is not up to specification, and that no certificates (as provided in ihe contract) have yet arrived—Carried.