D.—l.

At present Stoddart's Corner Substation chiefly supplies Banks Peninsula Power Board through a step-up 11/33 kv. transformer-bank. A route for a 33 kv. transmission-line will be determined and its erection between Addington and Stoddart's Corner will be proceeded with in due course. At various river-crossings anti-vibration jumpers were fitted to the A.C.S.R. conductors to prevent the breakage of the strands at the clamps due to crystalization caused by vibration of cables between line-supports. Lake-level and Rainfall. The year has proved exceptionally dry, and the lowering of the level of the lake has caused much anxiety to both .this Department and supply authorities and their consumers. In 1929 the average rainfall over the lake area was 41-89 in., whereas in 1930 it was 25-18 in. The lowest level of the lake was recorded as being 1,658-5 ft., and in March the maximum height of 1,667-55 ft. above sea-level was registered after drought conditions. The level of 1,658-5 ft. represents a drop of 13-5 ft. below the normal lake level of 1,672 ft. The rainfall at the power-house for the calendar year 1930 was only 22-05 in., the lowest on record, as against 36-28 in. for the previous year : 6-80 in., out of the total of 22-05 in., fell in January when the lake was at overflow level. Tai Tapu Dairy Co. I have to report that amicable arrangements have been arrived at whereby this company, one of the oldest consumers of power from the Lake Coleridge scheme, will on Ist July, 1931, hand over its functions as a supply authority to the Springs-EUesmere Power Board. HORAHORA - ARAPUNI ELECTRIC - POWER SUPPLY. 1. Capital Outlay. The total capital outlay at the end of the year, as shown in Table X herewith, was £3,939,122, an increase during the year of £278,695. The main items of increase were £49.336 on headworks at Arapuni, £44,494 on the generating-station, transformers, and other machinery, which includes part of the cost of No. 4 unit, £47,544 on remedial works at Arapuni, and £106,754 in interest during construction — i.e., approximately ten months' interest on works not in operation. The value of assets in operation at the end of the year (Table IX) was £1,286,667, as compared with £3,330,011 and £1,142,346 for the two previous years, the drop in the one year of over £2,000,000 being due to the closing-down of Arapuni and those other parts of the system which are not at present required to deal with the smaller amount of power now being sold. 2. Financial Results of Operation, and Future Prospects. The gross profit for the year — i.e., total revenue, £184,593, less working-costs, £101,889 —was £82,704. Working-costs includes an assessed amount of £20,737 to be paid to the Auckland Power Board as part compensation for the use of King's Wharf plant as a standby, so that the gross profit on actual supply of power by the Department was £103,441, or 5-99 per cent, on the average capital outlay. Interest and depreciation charges for the year amount to £118,398, so that the loss on the year's working was £35,694, inclusive of the payment mentioned, and £14,957 without including that payment. The corresponding loss the previous year was £32,768. Operating or working-costs are analysed for the past four years in Table XI herewith, and show the following points : Increase in total operating-costs, principally due to increased use of the fuelplants and increase in standby provision. Increase in operating-costs at Horohora, due largely to increase in amount of screen-cleaning necessary to get the full output from the plant. Increase in transmission-line and substation operating-costs in 1929-30, due to the increased mileage of lines and additional substations brought into operation at about the same time as Arapuni. 3. Extensions during the Year, and Future Extensions. (a) General, Additional Consumers, and Connected Load. There were no additional consumers during the year. The connected load, not including Auckland electric - power district, has increased from 89,523 kw. to 99,341 kw. The number of milking-machines supplied has increased from 4,988 to 5,493, electric ranges from 2,807 to 3,420, and water-heaters from 7,088 to 8,229. These are exclusive of Auckland Power Board figures. The system maximum-load figures for the past three years are 15,900 kw., 41,520 kw., and for this year 49,520 kw., when Arapuni was supplying, and 17,600 kw. since that time. The demand factor (not including Auckland) was 17-7 per cent. (b) Power-stations. Arapuni. —The erection, of the three units comprising the initial installation had been completed the previous year, and the erection of cable-work and switch-gear for No. 4 unit was in progress at the end of this year. No. 4 turbine and generator arrived, and were stored at Putaruru Station-yard.

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