HARBOUR INQUIRY

Hawke's Bay Tribune, Volume XVII, Issue 216, 26 August 1927, Page 7

HARBOUR INQUIRY

ANOTHER ALLDAY SITTING

ESTIMATES OF COSTS. MR. R. W. HOLMES QUESTIONED Ike Napier Harbour Commission continued its sittings yesterday aiteruouu, wfieu al. It. it. Holmes,, consulting engineer to the Boaril, gat< lurtiiei evidence.

In discussing the question with li witness, said Mr. Holmes, Mr McKenzie suggested that the ebb tide might follow a course striking a vessel on the starboard side and rebounding off the eastern mole strike her ou her bow quarters causing her to be swung round between two currents. Observations made showed that no rebound occurred from the East mole, but flowed along it out to sea. Vessels entering on the ebb tide would therefore have only one current to contend with.. The Har bour Board had had vested in it considerable endowments for harboui purposes, their initial values not being very high as they consisted chiefly of swamp lands. During the last 40 years improvements had been effected so that they now had a much greater value which could be increased at a moderate cost- To dispose of their freehold or to -have them transferred to any other local authority .would mean a. distinct loss, and the handing over to another local authority would be parting with an asset which at present formed a security to those who had lent money to the board.

Mr. Barton: So far we are in agreement on that point. An engineer, who might be instructed to construct a railway lietween two points would be guided by two outstanding features- the ‘cost and sources of obtaining revenue. The some principle applied to every work, and should be applied to the making of a harbour for the Hawke’s Bay district in the most economical manner in spite of the difficulty set up bv various captains, and which could be overcome. No engineer would have any hesitation in recommending for adoption a harbour which could be constructed for £1,000,000 less than the other, that was dealing with the nett cost and other things being equal This concluded Mr Holes’s evidence and Mr Lusk intimated that he did not wish to cross-examine. COMMISSION S QUESTIONS. To Mr Barton: We have not been instructed to do anything in regard to repairs to the Breakwater. You gave the cost of the Breakwater at £ll2 per foot. Do you know what reclamation costs in various parts of the locality?—l could not say. Your estimates for the Breakwater Harbour don’t include any cost fol repairs to the Glasgow wharf?- No, Does that mean the abandonment of the Glasgow wharf?—We only estimated for two new berths.

Mr McKenzie: How do you account for the deepening of a great deal or the sea bed from the foreshore to -he 30ft. contour line between the Breakwater and the entrance to the Inner Harbour?—By the action of the sea and by erosion caused bv ships’ propellers Is it not a fact that there is a great deal of this area over which vessels do not pass ?---Wherever the sea bed consists of erodable material within the disturbing influence of wave action, it was always liable to be moved when disturbed bv currents.

1 suggest that your explanation is nop consistent with voiir statement that the sea bed was highly resistent to dredging by pumping —1 believe that. 1 described the sea bed as consisting of line sand held together more or Jess by mud derived by the grinding action of the shingle. This would resist disturbance more so than sands of volcanic origin. Do vou anticipate that the dredging of this channel would be difficult?—The deepening has taken place over a period of many years. Our estimate on the cost o f dredgings w«. based upon experiments carried out by the Kaione in Wellington in similar materials.

Can I take it that the deepening has been largely due to wave action? —Yes. practically. You refer to the difficulty of filling the hopper and taking a full load. Dp you suggest taking half a load?— Well, think it would pay to go on pumping.

lou sav that the natural channel west of the moles is 23 feet deep ?— Yes.

1 worked it out. and vou would have a curve of 3000 feet radius?— Well, they have a curve when entering in Wellington. If accidents have happened in a curve of a mile radius it must have been due to bad navigation.

You agree that there is a drift coming round the end of the Breakwater that will require dredging?— Yes ; in order to keep the Breakwater entrance clear.

How long would it take to make the Inner Harbour ready before dredging the channel?—About two years.

How long would it take to dredge the channel?—That would depend upon the weather. I could not offer an opinion.

If there is no accretion of material coming from the outer harbour to the Spit, would there be a tendency for the_ sea bottom to flatten?—Yes. You refer to the uncertainty expressed by Maxwell, Williams and Mason as to the keeping open of the Inner Harbour channel? —That certainly does not exist. Do vou suggest that the extension of the Breakwater Harbour would create siltation in the Breakwater — No, not assist siltation. but cause a confused sea. I would like to see the end of the Breakwater brought out a little further to clear the end of the mole. , PARKE ISLAND STONE. I understand that the stone at Parke Island is costing 34s Id per yard?—Yes. Seeing that the stone is in limited quantity, would not a satisfactory work be got bv concrete on a 1-3-5 basis?—l would prefer a 1-21-5 basis. All the stuff showing at the Breakwater would come within the designation of sand, being less than one quarter inch. When 1 saw it yesterday morning it looked much larger than that? — It is certainly very fine. You refer to a number of reports as being really only the opinion of one man owing to their continuity?—

Yes. 1 consider that thev can really only be regarded as one report owing to the continuity of individuality, i say that, knowing the man. Maxwell would be the dominating force. 1 say that B uch -engineers as Cvrus Williams and J. Blair Mason add nothing to Mr Maxwell's opinion. I protest in having to express such opinions, as it is a little bevond the bounds of professional etiquette. 1 know Mr Maxwell personally, and was only relating to his force of character. These gentlemen are nil capable. In dredging the outer channel vou have allowed a batter of 1 in s?— Yes; I consider that in the construction of the outer channel, where it passes through the outer bank, it would be sufficient. After construction 1 would not expect there to be any maintenance tor the first three years.

Would vou expect it to narrow in that time?—The sides may fritter a little. Do you say that Cullen and Keele did not refer to the height of the Breakwater. You must have overlooked this paragraph (which was quoted) ?—That only refers to the type, not height. These engineers came back after twelve years and saw that the Breakwater had evidently stood well without suffering much damage. Thev must have thought it sufficiently high enough?—A B a breakwater, but not for shelter. You think it would be quicker to build in mass-concrete than in reinforced’ concrete?—Y’es and cheaper. Would it not be as difficult to build a wharf at the Breakwater as at the Inner Harbour?—No not in massconcrete.

During flood period the Tutaekuri brings down large quantities of silt —Yes.

Suppose the river is diverted to the Waitangi would that increase rhe quantity of silt brought round the end of the Breakwater?—Y’es. it iav be. Mr Watters: What would be the cost of a tug ?—About £25,000. You .say that traffics could be worked more easily on a quay wharf than on a T wharf?—Yes, the principle of cross-overs would be simpler. The traffic at Westport and Grevniouth is handled’ quite easily. Where vou have to handle full and empty trucks when there is a rush on. would there not be some confusion? —No. that could be got over bv the building of a third line. At this stage the Commission adjourned till 10 o’clock this morning.