C.—ll.

No. 31 Light Diesel Drag-line excavator is the recent addition to the plant. It is equipped with a 65-horse-power engine and operates a J-cubic-yard bucket on 40 ft. boom. The machine was delivered in January, 1940, and after a complete overhaul commenced work in February, 1940, on the right bank of the Tarawera River near the Factory Road. Approximately 2,800 cubic yards of material was excavated from the river and placed on 5 chains of stop-bank. No. 32 Light Diesel Drag-line excavator, after completing some repair work on the Mangaroa drain, commenced work early in the year on a drain-enlargement scheme involving 66,000 cubic yards of excavation from the Edgecumbe catchwater and Seccombes drains. This work is being carried out principally to provide drainage for an area of 6,700 acres of the Putauaki Block, which is being developed by the. Native Department. Heavy reconstruction at the lower end of the Catchwater drain has now been completed for a distance of 1 mile 15 chains from the Rangitaiki River. The output of this machine for the year was 36,000 cubic yards. No. 6 Priestman Dredge, which has been laid up for some years, sank in the Awaiti Canal and was raised and beached in a safe position. Flood-gates. The large flood-gate commenced last year near the mouth of the Orini Stream has been completed. This structure comprises three 5-ft.-diameter cast-iron automatic gates which will prevent tidal flow up the Orini Stream. As a protection against erosion of the sand under the base of this structure, the entire foundation was enclosed with steel-sheet piling. To avoid the difficulties of underwater construction, a site for the structure was chosen where it could be constructed in excavation, and though this site was over 300 ft. from open water, special methods had to be adopted to reduce the pressure of the percolating water before the concrete foundation slab could be laid. A new channel has been excavated to carry the stream-flow through the flood-gate, and the old channel will be closed next summer after allowing time for the banks of the new channel and filling to stabilize. A small flood-gate and 3-ft.-diameter culvert was constructed on the Orini Stream and another of 4 ft. diameter completed on the Omeheu Canal. The deepening of the Edgecumbe catchwater and Kopeopeo Canal necessitated alterations totwo bridges, and a farm-access bridge was constructed on Central Drain. Rangitaiki River. River-channel-improvement work commenced some time ago has been continued. During the year the right bank of the river was cleared of willows for a distance of 86 chains upstream from the Edgecumbe Bridge. Bank-protection work has been assisted by the absence of severe floods in the river. Tarawera River. Freedom from floods and the temporary repair work carried out last year accounts for the fact that there were no breaks in the left bank stop-bank of the Tarawera River this year. It was pointed out in a previous report that the condition of this stop-bank is a menace to the district, and arrangements for the reconstruction and maintenance of this bank are matters of urgent necessity. Some bank-protection work was carried out above the Whakatane-Tauranga State Highway bridge. Maintenance. The Department undertakes the maintenance of 158 miles of canals and drains. This work is carried out with mechanical excavators and weed-cutting launch in the canals and larger drains and by manual labour in the small drains. The total length of the drains constructed by the Department to date is as follows : — Miles. ch. Dredged canals .. .. .. .. .. .. 68 43 Main drains . . .. . . .. . . .. . . 121 36 Road drains .. . . .. .. .. . . 30 46 Length. Summary of work carried out during the Year : — Miles. ch. Drains and canals cleaned by manual labour .. 123 36 Excavation Drains and canals widened and deepened by manual Cubic yd. labour .. .. .. .. .. 4 74 6,600 Drains cleaned with weed-cutting launch .. 14 74 Drains and canals improved with excavator .. .. 5 60 126,000 New canals constructed with excavator .. .. 0 15 16,000 Stop-banks constructed or repaired with excavators .. 1 35 59,000 Stop-banks repaired with manual labour .. .. 0 8 350 207,950 River-bank cleared of willows .. .. 1 mile 6 chains. Flood-gates completed .. .. .. .. Three. Bridges erected .. .. .. .. .. One. Surveys carried out involved — Traverses .. .. .. .. ..171 miles 25 chains. Levels .. .. .. .. 23 miles 19 chains. I have, &c., R. L. Innis, Chief Drainage Engineer.. The Under-Secretary for Lands, Wellington.

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