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Regular investigations are being carried out not only on irrigation works, but also on other water-supply proposals so that adequate data may be available for considering further schemes if necessary. In these times the potential increase of food production by irrigation cannot be overstressed, and to assist in this I have arranged for the Irrigation Engineer to investigate the best and most advanced methods abroad and to study conditions generally relative to this important matter. LANDS IMPROVEMENT This important productive work also has had to be curtailed due to the shortage of man-power and plant. This has been further accentuated by having to utilize plant in repairing flood damage and on other urgent works. Reclaimed areas have been improved at Ruawai and Naumai by the raising of stop-banks. In the north, farms have been benefited by the extension of water reticulation. A limited programme of sand-dune reclamation has been undertaken, and in this field an improved organization is in course of being built up for future work. Records kept of land-clearing activities show the importance of this work, and in practically all cases where full advantage has been taken of the cleared areas considerably increased production has resulted. COAL PRODUCTION During the year my Department has assisted the Mines Department in every way possible with the production of coal from opencast mines in various parts of the country from the Waikato to Southland, and a great amount of work has been carried out with heavy plant. Access has been provided, large areas stripped of overburden, camps erected, and sidings, bins, and loading arrangements constructed. In addition, the coal itself has been excavated, and in many oases this has been done under very difficult climatic conditions. LIGHTHOUSES Little new work has been carried out during the past year. All structures and equipment have been maintained in a high state of efficiency, and, in general, living conditions have been improved by improving access, in some cases by road, in others by sea, and the modernizing of sewage disposal and water-supply services. PLANT AND MECHANICAL The period under review has been largely one of reorganization and transition from the demands of the war period to the preparation for the post-war programme of works. The zoning control system established some eighteen months ago has proved its worth, particularly in times of emergency, such as during the recent disastrous floods in South Canterbury. A considerable amount of plant is being returned from the Armed Services, and during the past year I arranged for the Chief Mechanical Engineer to visit America in order to arrange purchase of mechanical equipment and to study the latest methods of applying plant units to construction work generally. It was found that great interest was taken in the United States of America in the success of the zoning scheme now functioning in my Department. Plant has been made available as required to assist other Departments in respect of important national works of various kinds. Owing to the difficulty of importing special plant during the war period the Department has designed and successfully constructed certain equipment urgently required such as a radial cableway at Karapiro and large-capacity concrete-mixing plants. In connection with river-control projects which must feature largely in the remedial measures to be adopted in order to alleviate economic losses due to major flooding, special excavating machinery has been secured from the United States of America, where experience over many years has demonstrated their suitability and efficiency. In the process of widening, deepening, straightening, and diverting river channels, particularly of the larger waterways in the Dominion, a considerable amount of earthwork will be involved, aggregating millions of cubic yards of material, and it is recognized to be more economical to use suitable large-capacity machines for this purpose than to employ a number of relatively small units. Two special-type tower excavators of the largest capacity so far produced in the United States of America have therefore been obtained which, because of their particular features, offer valuable advantages over the equipment hitherto used in this country. By reason of their operating range and height, combined with a bucket capacity of 12 cubic yards per lift over a span of 800 ft. to 1,000 ft. and a facility in dumping and trimming material, these machines will accomplish in one process what would otherwise require a series of operations by an assembly of smaller units. A particular advantage in the height and span of the towers is that the equipment will not readily be subjected to interference from river conditions during operations. The first of these machines is now being assembled in preparation for operations on the Otaki River below the main highway and railway bridges. The head tower is 130 ft. high and the tail tower approximately 30 ft. in height. The control cabin, which is part of the head tower, is 60 ft. above ground level, and this enables the operator to direct the work with uninterrupted view. For shift-work, flood-lighting is provided. The machine is operated electrically either from an independent Diesel generating unit or from the ordinary reticulated supply where power may be available. The excavating buckets vary in size and type, so that the appropriate type can be used according to the particular needs of the locality and the nature of the material to be removed. In favourable country and under suitable conditions the output of one of these installations can be conservatively estimated at not less than 150,000 cubic yards per month based on three shift work for six days per week. A feature of these machines, is that the time cycle of a single operation is reduced very considerably below that of other methods, and apart, therefore, from its excavating capacity the time factor in operation contributes materially towards its overall efficacy and economy. This equipment is of a type and capacity not previously seen in this country, but it is confidently anticipated that in respect of performance, cost, and speed results will be achieved which will prove eminently satisfactory from every viewpoint.

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