D.—l

Waitaki River Crossing. —This is part of the Timaru-Oamaru line, and reconstruction of the line across the river became necessary owing to one of the original towers being washed out in a flood. A new layout was prepared with only one tower in the river-bed instead of three on the old line. WaimaJcariri River Crossing. —This is on the route of the Addington-Southbrook line and some reconstruction became necessary owing to the wide diversion cut being made there. A single-span crossing on steel towers has been adopted. Lyttelton-Woolston Line. —A new line with heavier conductors was required to cope with the supply of power from the Lyttelton Diesel station. Quantities and a new design for the hill section of the line were made up and stringing data supplied for the conductors. General. —A specification was drawn up for concrete telephone-poles, and tests on same were supervised. Drawing and chart also prepared in connection with this pole. Investigation is being made into most suitable form of guy-insulators for wood-pole structures. In connection with line-insulators, data was prepared giving method of calculating surface-leakage form-factor for use with insulator specifications. ELECTRIC - POWER BOARDS. The development of the reticulated area of Electric-power Boards has continued to make progess during the year. There are now forty-five districts constituted, and forty actually carrying out the distribution and sale of electrical energy (August, 1931). The total area covered is 69,294 square miles, or 64 per cent, of the total area of the Dominion ; the total population concerned is 1,004,081, or 68 per cent, of the total population of the Dominion ; and the unimproved value of the land included in the electric-power districts and outer area is £257,184,874, or 73-5 per cent, of the total unimproved value of the Dominion. So far, only one of the four main cities —viz., Auckland—has been included in the inner area of a power district, but of the secondary centres the cities of Wanganui, Palmerston North, and Invercargill, and the boroughs of Timaru, Napier, Hastings, Blenheim, Greymouth, Gisborne, and Oamaru are included. The advantage of Power Board organization is more obvious to rural than to urban ratepayers, and yet the above position indicates that some of the more important centres have realized that it is to their advantage generally to be associated with the country in undertaking the work of reticulation of electric power on a comprehensive scale. The question of administration and operating costs in Power Board areas where more than one organization is engaged on the business of electric supply is being investigated with a view to arriving at an approximation of the resultant savings to be obtained if amalgamations or absorptions are effected. If such investigations show the expected savings, then it is in the interests of national economy generally and of the consumers in particular that effect be'given to the above objective. The following tabulation has been prepared to show the present position of each city, borough, and town district in relation to Power Boards actually in operation, and it reveals the fact that the benefits of electric supply have reached many places which might otherwise not yet be enjoying these benefits. Included counties have not been scheduled.

Table showing Grouping of Local Authorities for Electric-supply Purposes in Power Board Areas.

77

Power Boards In DistIict - In Outer Area ' taking Government —— —— — —— ——— — — - _________—.—_— ——■ SUPPly ' Purchasing Bulk. Generating. Purchasing Bulk. Generating. Ashburton .. .. Ashburton Borough. Tinwald T.D. Auckland .. .. Auckland City. Onehunga Borough. One Tree Hill Borough. Otahuhu Borough. Mount Albert Borough. Mount Eden Borough. Newmarket Borough. All town districts in Manukau County. Banks Peninsula .. Akaroa Borough. Bay of Plenty .. Opotiki Borough .. .. .. Whakatane Borough Whakatane Borough. Cambridge .. .. Cambridge Borough. Leamington T.D. Central .. .. Huntly Borough. Ngaruawahia Borough. Raglan T.D. Central Hawke's Bay Waipukurau Borough. Waipawa Borough. Dannevirke .. Ormondville T.D. Dannevirke Borough. Woodville Borough. Norsewood T.D. Franklin .. .. Pukekohe Borough. Waiuku T.D. Tuakau T.D. Mercer T.D. Hawke's Bay .. Taradale T.D. .'. Napier Borough. Hastings Borough .. Havelock North T.D. Havelock North T.D, Horowhenua .. Foxton Borough. Levin Borough. Otaki Borough. Hutt Valley .. Upper Hutt Borough. Lower Hutt Borough. Petone Borough. Eastbourne Borough.