The Evening Star TUESDAY, AUGUST 26, 1873.

Evening Star, Issue 3281, 26 August 1873, Page 2

The Evening Star TUESDAY, AUGUST 26, 1873.

Since first the question of dredging the harbor was seriously mooted in Dunedin, about fourteen years have elapsed; Mr J, T. Thomson having brought it under notice in a letter to Captain Cargill, under date 27th December, 1859. The subject was renewed from time to time, but seemed lost sight ot, for the Province has passed through a period of commercial depression, many, at that time too young to feel an interest on the subject, have grown to manhood, and are taking active parts in public life, and considerable changes have taken place in the population. It will therefore help to the formation of public opinion on the subject to give a short account of what has been done in the matter. The comparatively small area of ground available for commercial purposes immediately contiguous to the harbor, suggested the idea to Mr Thomson of reclamation, for the twofold purpose of bringing large-sized vessels to Dunedin, and providing wharfage and warehouse accommodation. Various plans were proposed, some of which have been partially carried out; but depressed trade, changes of administration, and other causes, have interfered with tho systematic prosecution of the work. In fact, it may be truly said no well-devised scheme has ever been proposed by which the harbor may be mado.avaiiuble for making Dunedin the port. Mr Swyer’s plan for dock accommodation, laid before the Council in 1863, was only partial, although it suggested the way in which the work might be paid for. He showed that the sale or lease of the ground reclaimed would pay the cost. In 1864, the late Balfour, then Marine Engineer, in his Departmental Deport, remarked ; It baa become a moot point with some w/hetber Port Chalmers should be connected with Dunedin by a railway or by a deep water

channel, and it seems to he considered that were one made the other would be unnecessary. This view I believe to be erroneous; while there is no part of the Province where a railway would be more beneficial to the public, I consider that the Government of the Province would be neglecting a very plain duty were the work of deepening the channel to Dunedin not also proceeded with. The towns of Port Chalmers and Dunedin may be compared with Greenock or Port Glasgow and Glasgow, as the position on the harbor and channel between them is much superior to that in the Clyde in the beginning of the present century. Were it difficult or impossible to make Dunedin a port even for large vessels it might be right to construct only a railway to Port Chalmers and to make that the great port of the country, but if it be found that a channel for large ships can be easily and comparatively economically made, it would be unjust to Dunedin not to give her a share of the shipping trade. The natural tendency would then be for the two towns to monopolise different branches of business for which their relative situations render each best suited, and thus each town would be more benefited than were cither to absorb the whole. As to the possibility of cutting a channel to Dunedin, I labor under a very great dearth of information, but shall assume the depths on the Admiralty chart to be correct at the present day, and that the stuff required to be removed is all capable of being lifted by a steam dredge with average facility. With these “hypotheses the channel could be dredged with much greater ease than. that of many of the rivers in Great Britain, of which I shall refer to a few.

There was a second session, in 1864-, at which the subject was touched upon in the Marine Engineer’s report, but merely to show that he had not been able to arrive at a more definite conclusion than before. In 1865 the Sanitary Commission reported, and it was then that Mr Balfour first proposed a scheme for deepening the channel and keeping it open by the tidal scour. The plan marked out was, however, mainly in reference to the drainage of Dunedin into the harbor; a course which we may remark en passant he did not recommend; for although he does not directly say so, his report points plainly to the probability of the sewage being deposited at the head of the harbor or on the Peninsula side, and that if allowed to run into the harbor, it or an equivalent would require lifting out again at one time or other. His plan was to build a train-in»-wall with a circular head to direct O the course of the tide. Like every other scheme of drainage, those who have talked and written on this subject have taken his estimate of .£04,550 as the cost of drainage of the City; while in reality it only represents the outlay by which the drainage of the City can be carried to a safe distance from it for sanitarypurposes. The system of City drainage would require paying for in addition. His plans were based upon and illustrated by the Admiralty Chart, which he considered very imperfect, but which gave the best data available. Underdate November 15, 1865, Mr Balfour furnished his final report, in which he expressed the opinion that a channel to Dunedin, 21ft deep at high water, could be formed for £78,000, or, including plant, £IIB,OOO. The only passage in that report that is of primary importance is that referring to the necessity for a survey of the harbor. Without that, neither drainage nor the construction of a canal can be safely proceeded with. If the people of Dunedin are serious in their determination to make it the port of Otago, we feel convinced that the first step should bo the survey of the harbor. The passage we refer to is as follows :

I have again to recommend that a proper and complete nautical and engineering survey of Otago Harbor, from the Heads to Dunedin, be undertaken at an early period, as it would be useful in many ways. Besides throwing light on many important scientific questions, it would have a very practical bearing on many sanitary and other subjects ; such as the propriety of allowing the sewage of Dunedin to be discharged into the harbor ; the amount of reclamation which should be assumed as the limit of safe reduction of waterway, and the most advantageous form for such reclamation ; the practicability and cost of deepening the harbor by dredging, and the quantity and nature of the material which would require to be removed, Ac. Such a survey would also, by comparison with the Admiralty Chart, give some indication as to whether the harbor is improving or deteriorating ; and the latter would possibly give a clue both to the cause and its cure ; besides, it would form a valuable standard for future reference, thus enabling the effect of new works to be speedily and accurately ascertained. The survey would be a work of considerable magnitude, and its cost would of course depend on its minuteness ; but I consider that all that would be required could be ascertained in about six months, at a cost of from LI,GOO to LI,BOO, including boats and every other expense. Until the completion of such a survey, it is somewhat dangerous to express decided opinions on such questions as the form which reclamation at Dunedin should assume, though it is less difficult to say what form should be avoided ; and I most strongly recommend that solid embankments should not be projected into Dunedin harbor beyond the outer end of existing works.