THE IMPROVEMENT OF THE UPPER AND LOWER HARBOUR.

Otago Daily Times, Issue 6736, 18 September 1883, Page 3

THE IMPROVEMENT OF THE UPPER AND LOWER HARBOUR.

TO THE EDITOR.

Sir,—Tho construction of a canal soemato bo now wanted in opposition to Port Chalmers (at least I presume it is for that purpose). Has it ever occurred to the Dunedin folk that a splendid floating harbour may be vnado of our natural harbour ? and I believe the.rooney proposed to bo expended on such a caual would be better employed in improving what Nature has done for us in part, and doubly pay the expense. " The plan I propose is to block up the (Portobello) channel now existing between Portobello and Quarantine Island, by making an embankment or sea-wall (said wall to bo made so that no water could filter through); then from the north - eastern point of Quarantine Island run up the harbour a wall for, say, GOO.'t abutting on the island, with a quay or pier of 40ft wide on the opposite side. On G oat Island I would propose that the same be done, leaving an entrance 00ft wide, which should be provided with lock-gates-one at about 30ft from each (nd of quay wall, and one at SOOi't from outer gato. This would form "a lock largo enough to admit coasting and intercolonial steamers and ordinary ships ; while the larger lock, when used, would tako such ships as the Orient, &c. A bridge could be erected for traffic, if considered necessary, and the same machinery (hydraulic) would do for working the locks, bridge, and supplying water to tho floating harbonr. A second wall or embankment would be required betwoen Goat Island and Port Chalmers to close existing outlet known as side channel, and thus form a direct route from the Port to the Peninsula, which I think is tin object much desired. (Should it not be thought practicable to form a floating harbour, I think tho closing of the two entrances named would assist in keeping the Victoria Channel S>en"' more efficiently than at present.) y adopting this plan the great amount of money which has been expended on' tho Victoria Channel would be found not to have been spent in vain, and as the training-walls are partly formed the reclamation could be carried on, and the harbour endowment thereby enhanced in value. I fancy this scheme would suit Port Chalmers and Dunedin people (as regards the expenditure of money), and stopthe bickerings which have lately taken place, I am of opinion that tho money now being expended in dredging the Victoria Channel will not answer the end desired or expected, as each scour of the ebb tide must bring down a sediment while the hirbour is open as at present and the training-walls incomplete, and will continue to do so ; for it must be borne in mind ours is not a harbour with a.scour sufficient to carry away such sediment, and this sediment tenda to silt up the bod of the channel. Had tho scour been sufficient, no dredging would bo required, either in the harbour or at the Heads.

This floating scheme snjigf stfd itself to me by seeing tho steamship itoilmw lying on the bottom at our wharf; and, 1 ask, is it feasible to expect ships to coinc up to DLinedin, to run the risk of lying even on a soft bottom, if they could paß3 tho Victoria Channel safely and without touching the ground ? As regards the bar, I propose that a trainingwall be run out to the edge of tho bar at about north-north-east from the lighthouse. I am also of opinion that training-walls should be run along either side of channel, from Quarantine Island to ■ Harrington Point on the one Bide, and from Koputai Bay to nprjosito the Heads on the other, thus allowing the channel to retain the courso as at present, which Naturo has devised ; and tho extra scour obtained after the completion of the work before mentioned would, 1 think, secure a depth of water sufficient for any ship to pass over the bar, come up the channel to the looks, aud Dunedin will be the ultimate goal. If anyone needs an illustration of how such a wall will be likely to act on the bar, I would recommend a visit to Mr George's in the Octagon, and by consulting the'plan of harbour exposed in his window, will not fail to see that tha current setting round Taiaroa Head and meeting the current out of the harbour causes the narrowest part of the bar nearest the Heads.

Many (and the Harbour Board among the numbor) anxiously await Sir J. Coode's opinion, &c. Question : Will Sir J. Coode guarantee to remove the bar and keep it open, even if all the money he. mentions be spent on tho undertaking? Question : Are there not many men liviug now who were never trained as engineers, but, having brains, can make use of them ? Question: Was Brindley, who planned the Bridgewator Canal, a. trained engineer? Let anyone take up Smiles' " Self Help " and see what our greatest men rose from. And are there not in Otago men who are willing and able to grapple with this undertaking, and who are willing to stake their little all rather than be bested ? 1 venture to say, Yes, there are.

I have not seen any of the plans which have been put forth by the various parties claiming to know how to remedy the existing difficulties, therefore it must not bo presumed that I have any interest in any scheme, and you, Mr Editor, know I have never written on this subject before. What I have stated has been the outcome of a little thought, and the only guide I have had has beeu the plan or map referred to.

Should tho training-wall at the' Heads bo found not to answer all I expect, it would certainly not interfere with ships entering and leaving the port. But lam of the opinion that it is tho only sure method to remove the bar, and the sooner it is done the better for the Port and the Colony. Captain Thomson, .who has held tha position of harbourmaster for so many years, should be able (and doubtless is) to Rivo us some idea as to what should be done. I would rather follow his advice than that of any nonresident engineer, even if he haa a handle to his name.

Trusting that someone abler than I am will take up this matter, and that eventually some good may'result,—l am, &c, Novice. Dunedin, September 15.