C.-8

4

Details of subsidiary drainage construction and maintenance carried out during the year are :— Excavation. Cub. yd. M. oh Drains cleaned .. .. .. .. .. .. 209 0 Drains widened and deepened .. .. .. .. 38,159 22 40 New drains constructed by manual labour .. .. 34,190 11 13 New drains constructed by machinery .. .. .. 48,845 2 36 Stop-bank improvements .. .. .. .. 5,989 3 46 Bridges, Buildings, and other Structures. Three hardwood road-bridges have been constructed, and one concrete culvert. Maintenance and minor repairs have been carried out to wharves and buildings. The total number of wharves at present in use is seventeen, and the buildings connected with the work comprise twenty-one houses and small cottages, fifteen double huts, twenty-six single huts, three workshops, staff quarters, five house-boats, and two offices. Rent received for residences and huts during the year amounted to £461 18s. 3d. Plant and Machinery. There have been no important additions to the plant this year, which comprises ten dredges and excavators, seven launches, steam-tug, two metal-barges, four general-service barges, six tractors, well-equipped machine shops, and large road and general construction outfit. A large amount of necessary repair work has been carried out on the plant at the Kerepeehi Workshops, and much of the floating plant has been docked and repaired. A punt for coal was built on the works. The distribution of stores, fuel, and construction material has kept three launches fully occupied and the various stores busy. Surveys. The surveys, hydraulic and soil investigations of previous years were continued and amplified this year. 136|miles of levels were taken, 14J miles of traverse and 19 square miles of topographical survey completed. Over 300 stream cross-sections were taken, and 265 borings for determining the subsurface conditions in peat land. Seven automatic gauges are in use to record the water-surface fluctuations on the Piako and Waitoa Rivers and Hauraki Gulf. Three of these gauges have been calibrated to give the stream-flow for any water-surface elevation but, owing to changes in the conditions due to dredging, frequent current-meter measurements are necessary to maintain accurate discharge-rating tables. Dailydischarge diagrams for both the Waitoa and Piako Rivers under flood conditions furnish the basis for all investigations and conclusions relating to flood-control problems. Flax Leases. Some nine flax leases are in operation over a total area of 3,095 acres. The annual rental on these leases amounts to £1,375 ss. 6d., whilst the actual revenue received during the year was £1,694 os. 9d. Grazing-areas. The total area leased on a temporary tenancy for grazing is 9,636 acres, divided into fifty holdings. The annual rental amounts to £864 ss. 3d., and the sum of £789 lis. lOd. was received during the period under review. Artesian-water Bores. No artesian wells were put down during the year, but to date 219 bores have been sunk, at a cost of £7,185 6s. Bd. The greater portion of this amount is recoverable from settlers, and interest is charged on outstanding amounts. £236 3s. 7d. was collected during the year, representing principal £182 lis. 9d., and interest £53 lis. lOd. Works Expenditure. The total expenditure was £57,489 7s. 7d., of which £31,781 2s. 6d. was paid from Thames Imprest Account. Day labour amounted to £31,860 10s. lid., and piecework contracts £5,178 2s. 7d. Maintenance Rates. For the 1926-27 rating-year some 547 rate notices were sent out, the maintenance rate struck totalling £7,880 15s. During the year the sum of £5,887 9s. 9d. was collected. Future Proposals. Works now in hand are to be continued during the coming year. These are principally Piako River improvements, flood-prevention, drainage and roading in the Awaiti district and Kerepeehi Block, continuations of the Waitakaruru-Maukoro Canal, and subsidiary drainage and roading on the western side of the Piako River.