Kat-O Pier
249. A contract for the construction of a small pier on the Island of Kat-O in Mirs Bay commenced in June. The precast reinforced concrete members for this pier had been built at the North Point Depot and completed by the middle of October and the transportation, handling and driving of the piles presented no special difficulty; driving was completed by the end of November. The construction of the decking and the stone pitched causeway followed immediately and the pier had been substantially completed at the end of the year.
Tap Mun Pier
250. For this pier, on account of site conditions, hard rock without any cover being present at shallow depths, caissons were adopted in the design of the pier head in place of normal concrete piles.
251. Two caissons of different sizes were precast on timber cradles at the Port Works slipway at North Point, the bigger of which was completed in October, launched, towed to site and sunk in position.
252. The smaller caisson was completed and launched in November. The 25 mile tow to Tap Mun commenced in fine weather at 07.00 hours on 14th December. The weather remained fine until the afternoon when it steadily deteriorated with the wind backing to north-east and strengthening to force 5, causing rough seas to break over the bow of the caisson which developed a list to port. Attempts to come alongside and bail out the caisson failed due to increasing seas and the tow was resumed at slow speed. Shortly after rounding Bate Head at 17.00 hours with heavy seas breaking over the tow, the list became more pronounced and the caisson sank in deep water. Although the coxswain of the towing vessel showed great presence of mind by attaching a life-buoy to the tow-bridle prior to casting it loose so that the sunken caisson could be easily located, salvage efforts failed on account of the difficult diving conditions.
253. To build another caisson would have unnecessarily delayed completion of the pier, and the work was redesigned and completed by constructing underwater 'tremie pipe' concrete walls.
Government Stores Wharf, North Point
254. This 200 feet by 25 feet wharf was constructed in reinforced concrete on a precast piled foundation. The work was completed well ahead of schedule and the pier handed over to the Stores Department at the end of December.
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