GREYMOUTH HARBOUR

Grey River Argus, 15 February 1945, Page 3

GREYMOUTH HARBOUR

Breakwater Extensions BOARD APPROVES PLAN. At its meeting last evening the Greymouth Flarbour Board approved a plan prepared by the Engineer (Mr D. S. Kennedy) for the proposed extensions to the north ancj south breakwaters. The plan will now be sent forward to the Marine Department. In a report accompanying the plan, Mr Kennedy said it was submitted for the formal approval of tie Board before forwarding it to the Department for consent and sanction by Order-in-Council. This step was being taken at this stage so as to implement the work when finance could be arranged and to save any delay. “The Committee of Engineers, Messrs Wood, Holderness and Johnston, who recently reported on the matter, considered inter alia that the proposals for extensions of 400 ft on the south side and approximately 486 ft on the north side (to bring the north mole co-terminus with the south) should be gone on with,” the report continued, “'t’his was on much the same lines as my; earlier report. As a first step, the present north mole should be brought into line with the end of the south mole immediately. This will involve a length of about 86ft of new construction, but I have drawn up my plan so as to cover all the extensions proposed, indicating on the same plan the above 86ft of new work. The actual design of the breakwater has been left to me, and this is now shown on the attached plan. I have studied many types of breakwaters as built in various ports of the world, but the storm and sea conditions here are such, and the capacity of plant, available in New Zealand so limited, that any departure from a standard type is inadvisable. I may say that it is going to be a difficult undertaking to push . the north wall out in the face of heavy seas and storms. A NEW APPROACH.

“However, the use of quarry stone in its entirety and placed by the old methods of tip trucks and staging are so slow and costly and liable to destruction, that a' new approach to carrying out the work is contemplated. ' I have, therefore, shown the breakwater .section to be built in two classes of stone, one placed by a special cantilever crane"for' the core mound and the armour coat by the jib crane, the whole to be heavily capped with concrete monoliths and 60-80 ton apron blocks. The work should be carried out as quickly as possible, and I have suggested that the 86ft length b e done in one y|ear by our own staff and thu 400 feet in 21-3 years by contract. In regard to the final width of entrance, this has been shown as 450 feet a'l low water ordinary spring .tides, but I propose Hint this should be subject to alteration as the work proceeds, if any undesirable effects lie found. F inally', in regard to alignment it is proposed that the south mole be taken out on the present bearing of 306 degrees, 50ft, and the north wall be turned in at 300 degrees, to give the necessary reduction in width. It is possible under the method of construction I have proposed, to modify’ or otherwise alter the alignment during the course of the work and when and as the results of the model tests become available. “To enable a start on the immediate extension of 86 feet on the north mole, £21,200 must be available within; 12 months—£4,ooo of this for the special plant for placing the core mound, a gravel plant, and a large concrete mixer to meet the much greater output of concrete required. Apart from the above, it is possible to put the work in hand almost immediately, but extra staff would be required. Otherwise our present staff of five or six men will continue the work as far as possible on the half tide training wall, which at present I am giving priority.”