CALLIOPE DOCK.

New Zealand Herald, Volume XLVIII, Issue 14586, 24 January 1911, Page 6

CALLIOPE DOCK.

FITNESS OF'" MACHINERY,

ANSWER TO CRITICISM.

On returning to Wellington after an in« spection of the Auckland wharves andi docks, Mr. T. M. Wilford, Mayor o£ Wellington, passed certain criticism on tho dock accommodation offered in this port at the same time speaking in terms of, commendation of the ferro-concrete wharves. Summarised, .Mr. Wilford'a criticism amounted to a statement that the pumping machinery at Calliope Dock was obsolete and worn out, the gate wasfaulty, and that the dock could not compete with other well-equipped docks X'hese criticisms were answered seriatim! by the engineer to the Auckland Harbour, Board {Mr. W. H. Hairier), when interviewed yesterday.

Mr. Harrier remarked that it was always a pleasure to show Mr. Wilford round the harbour works on account of the keen interest he evinced in them. On his last visit Mr. Wilford discussed almost all harbour topics with Mr. Hamer with tho exception of the docks, which this tim they did not visit. -Apparently tha figures Mr. Wilford had used in his criticism were an echo of the Union Com- 1 any's complaint regarding dock dues 6ni the Atua, which had several times been before the Board. . Mr. Wilford referred to "tho report of the Harbour Board engineer, which admits that the presentmachinery is obsolete and worn out,'' This was precisely what the Union Company had referred to, but Mr. Hairier was not' aware of any report which said eo. Calliope Dock was well ahead of its day wheal it was constructed 23 years ago, and w a ' 3 to-day, so far as he knew, the deepest dock/' in Australasia. Consequently with the much larger rise of tide that occurred here than in Australia, it involved the re- 1 moval of a much larger quantity of water, when the dock was being pumped out.! Calliope Dock had 35ft depth of water upon its entrance sill at high water sprint tide. As against this, the Port Chalmers dock (which was favourably mentioned by Mr. Wilford), had only 22 depth of water, so that there was a difference in depth of 13 vertical feet, and Calliope Dock was 20ft longer on the floor than the Port Chalmers dock, so: that there was a huge volume of water to be removed at Auckland as compared with. Port Chalmers. The two most modem: docks at Melbourne had 26ft and 27ft on their sills and were shorter. Of the Sydney docks Mort's Dock had 22ft of water,; Woolwich 23ft, Fitzroy 21ft Sin, and Southland Dock (which was the largest and deepest) 32ft maximum. These were, so far as Mr. Hamer knew, the most recent docks. ■

Continuing, the engineer said that ba found, on referring to official figures, that.' Calliope Dock, which contained about one and a-half times as much water as; Port Chalmers dock, was recently pumped; down in 5| hours, while the contract tims for pumping the Port Chalmers dock was six hours. Both times related to occasions when no vessel was in dock. ■ The time taken when vessels were in dock, and. displacing water from: the dock, must be governed by the rate at which it was convenient for the owners to clean and paint them, and this largely, depended on the number of men employed. At : the present time the Board; was calling for tenders for powerful pumping machinery, to empty the dock from its full capacity in about 2A hours, but even! now it was almost always necessary to; slow the present slower pumps. The real; trouble with vessels such as the Atoa and : Navua was that they were comparatively small vessels of very light draft occupying a very deep dock of considerably larger capacity than they required. As an instance, Mr. Hamer said that in May,, 1909, the Navua. drawing only 15ft 6in ait entered the dock, "which had 33ft 6in of; water above its floor, and the' Atoa, drawing only an everage of 15ft, docked! with 34ft of water above the level of the' floor of the dock. In the first case, a!- 1 lowing for the height of the blocks and'; :the shallow draft of this vessel, it was necessary to remove a high prism oi water about 520 ft, long, 70ft in width,. | and 16ft 6in in depth before the vessel could touch the blocks, and in the casa of the Atua it was necessary to remove a similar prism 15ft in depth, and this was all useless water. It would, of course, be obvious that for the larger, deeper-draft vessels, for which this docs was specially : designed, there was much'i less useless water to remove. Notwithstanding the age and wear . of the present pumps, they were slowed down eten: for the "larger vessels. Some two years "ago a suggestion was made by the Union; Company that to meet such cases as thosa complained of the bottom of the dock ? should be filled up some feet with concrete. Obviously, said Mr. Hamer, they could be thinking only of their own -shal-low-draught craft, and not of the deepen vessels for which the dock was intended, and, equally obviously, such- a'... method would be very undesirable. What decided the Board to call for tenders for pumping plant was that some expenditure had; to be incurred upon the valves of the ex-! isting pumps, -and further ,< expenditure would be recurrent in maintenance. The economy effected in steam consumption by more modern pumps would reduce the working expenses, the maintenance costs would be less, and the expenditure would only be slightly more for new pumps than the total for various items on the old* The Board also had in view that Auckland would soon become the naval headquarters of New Zealand. - It was stated by Mr. Wilford, continued the engineer, -that the gate was faulty, and would not float in under 25ft of water. It had to be remembered that this particular gate, or caisson, was built, for a very deep dock, and, as such, had been quite properly constructed. It originally needed about 27ft of water in which to float, but recently an alteration was made to enable the gate to be floated in 25ft* It was because this gate was specially designed for a deep dock that it would not be safe to alter the ballast to make it float earlier on the tide.. The Union Company had said it should be made to floatat 14ft, i and " that the permanent ballast should be replaced .by water., These two ,• suggestions ' were impracticable. Mr. Hamer. said his experience had been that caissons were serviceable where the water levels only: varied within small limits, - and in his report on this gate two years ago' he had said : "It is unfortunate, for' the purpose of docking smaller and,, lighter ves(sels, that the entrance to the Calliops Dock *is closed by a caisson instead of gates, which could be worked without delay of wailing for flotation." Considerable alterations . had been made, or were in contemplation, for the improvement? of the dock. The width had been increased on the bottom, tenders for new» pumps were due in March, and provision was being made for increased speed in tilling the dock by placing two large sluiceways through the gate. These had beets constructed, and the Board- was only wait-; ing an opportune time for their installation.

Referring to the details given by 3'r. Wilford, to show the larger number of vessels that clocked at Port. Chalmers compared with Auckland for the months of October and November, Mr. Hamer said the Auckland dock was not credited with the smaller boats, tugs, a.nd gulf steamers. Allowing for these, the clockings wera about the same, although the Port Chalmers dock got a number of bigger ships, for which the size of dock was eminently suitable, and being the headquarters of the Union Company naturally-as many of their vessels were docked .there as could be arranged. Mr. Mamer~observed that/ vessels were docked whenever it happened to suit the convenience of their owners, and while docks were one of the first essentials of a well-equipped port, very few of them paid. In conclusion, the engineer remarked that small ships in large docks necessarily suffered some delay in clocking; and, possibly, in the consideration' of any new' dock proposal, the Board would think it desirable to divide the great, length of a. modern dock by an intermediate pair of gates, that would enable a section of the whole to be cut off, and so make it more economical for shallow-draft chips using a lame dock. ' " vi