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Pukaki Lake Control Works.— Design work during the year has included the completion of the spillway gates and lifting-gear and the sluice-gate-lifting gear, with arrangements for the manufacture of these. In addition, the construction of the dam and the spillway has been followed up. Tekapo Power Project. —Design work has been completed in connection with the intake, surge chamber, penstocks, tunnel lining, and ancillary features, together with arrangements for the fabrication and construction of these items. The work included the follow-up of construction on the whole project. Maraetai Power Project.— -Design work during the year has been concentrated mainly on the power-house and on final details of the dam and penstocks and the general mechanical equipment. Contracts have been arranged for the supply and fabrication of the various outstanding parts. The majority of drawings for this project have now been issued. Following a suggestion made by Dr. Savage, a trial-load analysis of the dam as designed was carried out in America. Mr. L. S. James, of the Design Office, was present in Denver during the analysis, which produced confirmatory results. Cobb Power-station Extensions design of the spillway is nearing completion and the majority of drawings are now under issue. Details of the power-house, penstock and surge tank, and of the mechanical equipment are now in full design. Roxburgh Power Project.—Design work is proceeding on the diversion channel and on crates and lifting-gear connected with the diversion and the spillway, together with a study of the problems connected with the dam. Sufficient drawings have been produced to maintain progress on the diversion cut at the site. In the meantime, models are under construction at the Gracefield laboratory for testing the hydraulic features of the provisional design. Whakamaru Power Project.—The design of this project is in much the same stage as Roxburgh, with which it has many common features. Owing to the shortage of experienced staff and the necessity for taking up the design of Waitaki, it has been necessary to arrange a halt in the design work on this project at the stage when the design of the diversion is complete. Waitaki Power-station Extensions.—The design of this work was taken up under high priority early in 1950. Preliminary drawings are in preparation. Tekapo Lake Control— Preliminary studies and a provisional design of the dam and sluice structure have been undertaken during the year, parallel with site investigations. Various.— ln addition to the above, design work connected with maintenance has been undertaken for the following operating stations: Karapiro, Tuai, Pinpaua, Mangahao, Coleridge, Arnold River, Waitaki, Highbank. Substations Design work on two of the major substations, Bunnythorpe and Otahuhu, has been brought to virtual completion during the period. Preliminary work on Haywards has been completed. Design work on some fourteen smaller substations and associated works has been m hand during the year. To ease the position in regard to design staff, the District Engineers at Auckland and Christchurch have been asked to help in the design of substations m their districts.

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