Harbour Developments.
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mound of 30 ft. in width brought up to a level of 2.00+O.D. and of an average depth of 21 feet. The wall is built on a foundation of cement concrete laid in situ, the face work being in coursed granite rubble masonry with lime concrete backing, surmounted with a cement concrete coping at a level of 12.75+O.D. at the seaward end.
Progress continued to be slow throughout the year, and the contract time, which expired on 31st October, 1924, was extended on the 19th June to the 10th January, 1926, on account of the difficulties met with in obtaining soft filling material.
By the end of the year 494 acres were completely and a further 94 acres partly reclaimed, while the rubble mounds, and nullah wall boundaries were practically finished. There still remain the wall coping and about 160,000 cubic yards of filling to be completed which should be effected by July, 1926, if the rate of progress is maintained.
Estimated Expenditure
Original Estimate. $730,000.00
1925
$150,000.00
Actual Expenditure
Expenditure to
1925
$83,875.01
31.12.25
$576,130.25
Construction of Waterboat Dock at Laichikok.—This work was referred to in paragraph 5 of Annexe L to the Report of the Director of Public Works for 1924.
It consists of the construction of a narrow wet dock 600 feet long and 120 feet wide. The parallel quay walls extend for 550 feet and provide 1,100 feet of berthage for waterboats giving a maximum depth of water of 12 feet below O.D. Water is supplied from 12 water meters. The head of the dock converges, forming a water cushion, receiving the outfall of an open drainage nullah 42 feet in width and about 320 feet long, spanned by a reinforced concrete bridge at the head of the dock.
The quay walls are of sloping cement concrete blocks, averaging 5 tons each, set by a floating crane on a pell mell rubble foundation in a dredged trench. A cement concrete plinth course is formed on the top of the blockwork bringing the work up to 2.50+O.D. The superstructure consists of coursed granite ashlar facework, backed by cement concrete and finished with granite coping.
The dredging across the entrance to the dock, roundheads and return walls at dock entrance was carried down to 36.00-O.D. The roundheads were built of mass concrete deposited in timber caissons.
At the beginning of the year the greater portion of the rubble foundations had been deposited, 210 concrete blocks out of a total of 1,580 had been set and about 86 feet of plinth course laid.