HARBOR IMPROVEMENT.

Evening Star, Issue 3492, 2 May 1874, Page 2

HARBOR IMPROVEMENT.

The following is the Provincial Engineer’s report to the Secretary for Works on the above; — I have to acknowledge the receipt of memo, of the 20th mst., relating to Harbor Improvement, wherein I am requested to express an opinion upon the feasibility of deepening the channelrcommunication between Port Chalmers and Dunedin, thereby admitting of access to the Upper Harbor by vessels of large tonnage • and m reply have to state that the limited time afforded me for entering fully into such an important subject, added to more than ordinary pressure of departmental work at the present tune, plaices me rather at a disadvantage in the matter of detail. However, the whole question appears to my mind to be greatly simphfaed from the conviction that any scheme for the deepening of the harbor must be based upon a thorough knowledge of the direction and velocity of the tidal current, and of the nature of the material forming the bed and substrata aided by a, correct map showing the truecoastIme, soundings, and position and extent of the shoal hanks; in fact, a complete nautical and engineering survey of the hirbor, as recommeuded by the late Mr Balfour—believing, with Mi J. T. Thomson, that no scheme should be attempted of a merely experimental nature, as it must be borne in mind that whatever course may be adopted towards improving the water communication, a very great expenditure must necessarily be involved. Moreover, the question of future maintenance is one of considerable magnitude, and if it is intended that it should receive that attention consistent with its importance, the |course already alluded to is the only legitimate one to pursue whereby information pan be acquired that may guide the adoption of a method of Harbor Improvement as complete as the natural resources at our disposal will permit. Having perused the elaborate reports prepared by the late Mr Balfour, I am free to confess that the mode of improvement suggested by him, in the shape of a central wall extend mg between the existing deep water and the upper harbor, is the only natural solution of the question, as by it alone can the currents be controlled and utilised to advantage. At the same time, it must be apparent that as the Dunedin sewerage and reclamation questions must form part of the scheme of harbor improvement, correct data of the nature above indicated are indispensably necessary before entering upon the minutiae of sectional formnature and position of channel wall and cost of its erection, the mode and exteut of dredging and disposal of material, together with an effective arrangement of shipping accommodation at Dunedin. Otherwise, any scheme, if attempted and earned out, will have a strong tendency to prove abortive or practically inoperative. I would accordingly recommend that a complete survey of the harbor between Port Chalmers and Dunedin be instituted, with the view of enabling an exhaustive report to be prepared upon the whole question in all its bearings, with a detailed estimate of the works required, embracing the deepening, of the channel and construction of protective works, providing requisite shipping accommodation, and necessary reclamation and sewerage works.—l am, &c,, D. L. SIMfBON.