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Waikato River Hydro-electric Development Investigations.—lnvestigations for future dam-sites on the Waikato River are now being carried out by the Public Works Department operating in close liaison with the State Hydroelectric Department. Efforts were concentrated last year mainly at Whakamaru, with the object of reaching a final decision regarding the dam there as soon as possible. Bmvnythorpe Substation*.—Excavation and levelling of the site was started in May, 1946, and was completed,, except for trimming to falls for drainage, by March, when 64,000 cubic yards had been moved. Formation for the railway siding is almost complete, the work including culverting, and the bottom lift of ballast has been placed. Roading is in hand, 44 chains of formation being complete, including culverting; and a start has been made with metalling. Cobb River Development.—lnvestigations of the foundation conditions at the proposed dam-site were continued. The geology of this area is unique and the country has needed an extremely thorough examination. In anticipation of an early start with construction, accommodation is being renovated and increased, routine maintenance of access roading has been carried out, and the full lengths of the roads from Upper Takaka to powerhouse and power-house to dam-site have been metalled. Prospecting for suitable concrete aggregate has been carried out and a quarry-site has been chosen miles distant from the dam by road. Formation of an access road to the quarry has been finished. An average of 73 men have been employed throughout the year. Lake Tekapo Development.—The principal work done during the year was on the tunnel, on which progress has shown a very great improvement. At the south end the old drive, which was such an obstacle to speed, has been passed and most of the preliminary troubles with the shield are over. At the north end a second shield was erected in the gate-shaft chamber and is now driving towards the first shield. A total of 516 ft. of tunnel has been excavated and lined with concrete blocks at the south end and 255 ft. at the north end. A dock-site excavation amounting to 30,000 cubic yards has been removed at the lake shore for construction of part of the intake. A start has been made with the power-house excavation. During the year a further 62 married quarters and 35 single men's quarters have been erected. By March there were 220 men employed on the job. Lake PukaM Control. —This work, comprises a dam and spillway and sluices equipped with gates for controlling the outflow from Lake Pukaki into the Waitaki River. The first step in controlling the lake is construction of the sluices. Excavation for the sluice structure, involving 84,000 cubic yards, was completed using heavy earth-moving plant; and the reinforced-concrete construction is in hand. It was necessary to build and equip a camp, and this was rushed so that most use could be made of the summer weather. Black Jack's Point Investigations: Waitaki River.—This proposed site for a dam has to be thoroughly investigated, and a 10-mile road has been constructed to provide access -for men and plant.

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