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Redoliff Scheme: 60 acres only have been irrigated out of an area commanded of 4,600 acres. The revenue from four irrigators has been £60 ; expenses, £794. Levels Scheme : 800 acres have been irrigated out of an area commanded of 12,000 acres. Revenue from 23 irrigators, £133 ; expenses, £2,065. Irrigation Investigations. —The regular observation of rainfall, run off, and general meteorological phenomena has been continued. Bores have been sunk to enable records of ground-water movement to be kept. These have already proved valuable in discounting claims in regard to seepage. Further bores have been authorized over an extended area and will be sunk in the near future. CONSTRUCTION AND IMPROVEMENT OF ROADS Construction has again only been of a minor amount, due to the general conditions limiting action oh these works. Surveys and investigations have been carried out in various areas more recently, with particular reference to access roads to timber areas in order to assist with increased timber production. Unfortunately, in many cases only timber areas will be opened by such roads. Considerable future planning is also in hand. The work done during the year comprises the following : formation, 38 miles ; metalling, 49 miles; completed bridging, 1,270 ft. ; culverts, some 2,550 ft. with 2,400 square feet of concrete ford. Maintenance to road surfaces, particularly those subjected to heavy military traffic in the past, has been carried out. The year has been marked particularly in the south by heavy rain storms and subsequent flooding. Extensive damage has resulted in South Canterbury and Otago. In South Canterbury damage to the extent of some £60,000 to roads and bridges has occurred, and twenty-three bridges have been washed away. The damage in Otago has not been so extensive in this item, but amounts to some £6,000. HYDRO-ELECTRIC DEVELOPMENT : CONSTRUCTION WORKS Waikaremoana. —This work is continuing with the best speed that the present man-power conditions, particularly with reference to tradesmen, will permit. The service roads have been maintained, some 7,300 cubic yards of crushed metal being required for this item alone. Grouting has been continued throughout. 98 cubic yards of grout, making a total of 1,780 cubic yards, have been injected to form a curtain wall near the head gate shafts. Very extensive drilling and grouting has been carried out at the intake section and tunnels. West of headgate shafts, 28,196 ft. of drilling has been done with 3,860 cubic yards of grout injected. No. 1 headgate shaft has been excavated some 70 ft. deep with a clear diameter inside timber of 12 ft. 6 in., but at this depth difficulty was experienced with an extensive water break-through. At present remedial measures are in hand. Progress has been maintained in the twin tunnels against considerable natural difficulties and under trying conditions for the workmen. Work has proceeded twenty-four per day, mostly on a wettime basis. The country is very broken, and water has been met with at all stages of the work. 383 ft. of concrete lining in No. 1 and 388 ft. in No. 2 tunnel has been poured this year. The total lengths now lined are 530 ft. and 437 ft. respectively. Grouting ahead of the faces and behind the linings continued, 28,494 lineal feet of borehole having been drilled up to date, of which 19,500 ft. have been completed this year, and through these bores 6,700 cubic yards of grout has been placed. The evidence of the success of this grouting has been continuously found as the tunnels have been driven through the grouted area. Seven contractors' drilling-machines and one departmental one have between them drilled a total of 69,449 ft., of which 21,177 ft. was reboring, the average boring rate being approximately 2-5 ft. per minute for contractor's plant and 4-2 ft. per minute for departmental plant. The total grout used in all sections has been 9,100 cubic yards, representing 3,720 tons of cement. Apart from the above major work, work on the penstocks has been pushed ahead. Excavation is in hand, 16 concrete pedestals have been completed, and steel plate for the fabrication of the penstocks is. held. 2,712 cubic yards of concrete have been poured in the power-house foundation alone up to February, and this work should be completed by September. Good progress has been made concreting the floor slabs and walls of the tail-race. comprehensive building programme, including school buildings and permanent staff accommodation, lias been completed, except for some single quarters. Karapiro Development—The excavation of the site, totalling 570,000 cubic yards, has been completed except for minor trimming ; and consolidation grouting has been carried out in the intake section, between the penstocks and in the cut-off trench of the arch section of the dam. The two cofferdams were completed about the middle of 1944 and seepage reduced to a workable amount by grouting and sealing with swamp mould. Boring and grouting of the cut-off trench on the up-stream face of the gravity and intake section of the dam has been commenced. At the end of the period under review the main power-house structure had been constructed to the level of the cable basement floor, without any major difficulties being encountered, while the office block and unloading bay were further advanced, making a total yardage of concrete placed in the section of 16,119 cubic yards. Good progress has been made also with the intake and spillway sections, where after extra excavation 8,637 cubic yards of concrete were placed in the former section from December, 1944, to March, 1945, and 15,500 cubic yards in the latter section. In connection with the spillway section, the syphon flumes are partially completed, and the lower level bridge was completed towards the end of 1944, j *nr i The concreting of the arch section was commenced in October last, and up to the end of March, 11,198 cubic yards had been placed with two-thirds of the arch bays under construction. The outdoor station has been completed, to the level of the mezzanine and switch-room floor. The total concrete poured in all these operations was 52,578 cubic yards, with 635 tons of reinforcing steel placed. Additional concrete plant, together with a radial cable way for concreting the arch section and a 10-ton crane, are being provided for the concreting of the dam.

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