THE COMING OF HYDRO-ELECTRICITY AT MANGAHAO

Otaki Mail, 17 August 1923, Page 3

THE COMING OF HYDRO-ELECTRICITY AT MANGAHAO

WORST ENGINEERING Diri'ICULTIES SUBMOtTNTED. WHY THE FAxUAES WILL BENEFIT. "Mew Zealand has boon reading long enough in the papers how olher countrios use electricity on the farm." "By 1924, Japan will have more hydro electric power developed and controlled by the Government than any other country in the world." These two statements in the booklet of the r/ranawatii-Oroua HydroElectric Power Board, placed in juxtaposition, are rattier striking. The time is not far distant, however, when this country, with all its tremendous natural resources of water power, will be able to come within "coo-oa" of Japan's electrical development. Mangahao, though not the first, is stho greatest scheme of this nature wliieh has yet been undertaken in New ZealanH, and will probably still be the biggest for years to come. Touching as it does, every noma, farm and business in the Manawatu, Iho following story of the work that is heralding the coming of Hie "jui&e" will bo read with interest.

SCIENCE 3JE.IUMPKS. . , t>n another occasion, « party of lour i was picceeding from Arapeti when the lii Tiiij HEART Ci' TliE iiU.'Jli. J cur slipped, for several seconds being S posed on the brink of a cliff; about 100 13 ivi :•v•> i v ■■',' irivc unci ! ' UL '' nigh. Another car coming bonutd raced recklessly to the rescue, but tun late. (>u e of the occtupants of the Up in tiiu hills and valleys above roar seat, who turns the scale at 14 Ulianuon, away troin the wonted paths stone, jumped clear at a bound, and 'i civilisation, amid the primeval the releasing'of this weight on the roar uiith, Oiie of the greatest eii«;inoeriiig wheels wjis sufficient to send th 0 car propositions that has been undertaken hurtling down cut to the. section o.£ the m Aew Zeatand is rapidly proceeding road below. Here, again, however, tjv,-.. iU ; completion. The small army there was a miraculous cscapo, the id on the Maugaiiao hydro- | throe remaining members of the party tieei'vic scheme, after many muiiths e£ ' who "went, down with the ship" escaptin remitting toil have at last brought , ing with sundry cuts and bruises. With tueir task To us final stages, but much I the relating of suck incidents (told, yet ri.-iuums lo be done, 'lac prediu- ! perhaps for a specific purpose, it is litHv.t that "jutou" will be available by ! tie wonder that the visitor heaves a 1 June appears lu Lie in u fair way to (sigh of relief when the track has been ! f..- : ,; = - piovidud that Nature auccessfully negotiated. ' J as no! present any further obstacles WORKERS* SETTLEMENTS*, "j < to eng.LeciS. .Since a previous visit, nearly two Accompanied by MebSW \\.A. reporter noticed Waters and .K. I-Jgmilon, ol the Mima- . ° ' , , , , ° ~ ' ...,-- ~ ... that many improvements had been vatu-Uioua Power Loard, a J mica '- . ~ , • c „ „ . , . .. .... , ~, ,„ made m the housing- ot tho reporter oaid a visit this week io "~ & . . ~' ■■ , ~ , F , „,.„„... workers and their wives and families. :.!- runthao, where the woik of haiuw-- ~,, caT . v , |a bcou laced by . i.. 8 the uver god is now at a.most in- substautiaJ &a stl . uctures , which tcie-tiu"-'' stage The two great tunnels uiaius su> o i,, ■ - <=■ „„„,.„„ i arc very cosy, and as convenient as Uuve been pierced, and the constiuc- circum _ tiM. ot the dams a t Manga ao and ± gathered together in Arapeti has been commenced boon £ wherever a seetian ot the uuso concrete ramparts will be gch [md erected, the by-pass tunnel which now washing day gave them an diverts the stream from its noirna homeliuess that was not discourse wtU be blocked the darn*.will 0OUIltC(J eKhor by tne he brooding lUI up and tho power will be iead>. foregt an &Q onQ Qr by thfi ia^ t iiall we.' sistent echo of a steam hammer on the 'I.'HLJ POWJ3K-HOUSB AKEA. other On arrival at Mangaore, the party THE AKAPETI UAil. was given its lirst indication of tho Practically all the labour at Arapeti magnitude of the undertaking. The j s now concentrate* on the construe-iJower-hause tnat is to convert the t j on 0 f t ] xe sr^a i dam, which will water into neat and power is rearing have a capacity of 300,000,000 galup it's wails, and already 7000 yards of lonE Af wft? tj, e case w ith the concrete nave boon used in the floor jfangahao dam. much difficulty was and water chambers alone. Five exp erienced in rinding a solid rock engines, three generating 0000 h.p. and lacfc in W hien the walls of the retwo 3000 h.p. wilt be installed when sei . voir wiu be setj and L , oLh sides of tho shell is compieie, together with an I]u hm have had t£) be cut backj oae excitei'. about 400 feet and the other about The pi.'.: line, waich wiU convey the lf)() feet A wooden flum e, supported water from the surge chamber 800 feet hy com . rele pjers that w ,itl eventually abuse tlte power-house, is now being ( , orm part Qf the waU Qf the dam _ laid, the pipes ueing ttirec lect in dia- Lal .,. ies the watei . a. ei . oss the su ily, i meter, difficulty in the matter ot undernetttn the rock surface, supplies has kept this work back ha bsfcn thorougll i y washed of all sontewhat, but it should be completed AM d preparatory to according to schedule. _ th<a lnvins ,j own 0 f the concrete, is A simple illustration ol the enor- dlgappcarlng as the final mous power that lies latent in a smaii construction work is bequantity of water was supplied by Mi * wee ks, the great ramWaters to our representative. An oU b thick at the base 5S t or *»!? ee? w-11l l"d 300 yards long, will he ready to , for a minute, hold the enormous pre«mre of water 1 Th c journey to the Arapeti camp is which vrdl flood, pei-haps, foi all -ill dangerous, especially in wet time, the valley which is now the veata«wnd all the thrills of the home of this division of the Public Wonderland switchback are provided Works' army of Mangahao. u the motor ear mounts spirally, with A short journey along one of the dec precipitous gullies on the one enormous li-.imlines brings one to the 'raid • ad towering cliffs on the other, twine* which connects up with ManThe hc"vy traffic makes maintenance gahao, while the longer tunnel to the work difficult, and considering the surge chamber above the power number and sharpness at the "hair- house, is some distance to the right. pin'' bends on the road, which in some I The concreting of these is being inslaners have to be negotiated by I pushed on with all speed, as fast as de-rces ' surprisingly tew accidents I the cement arrives. have occurred. <5>N xHE MANGAHAO. A. TREACHEROUS KOAD. Leaving Arapeti behind, another At one ijart Of the road, however, journey over an even more execrable tlii; chassis of u motor lorry bears mute , part of the road, brings one to the witness to a recent smash, and atj j,in overlooking the last great link in glance down tho side of the hill reveals Ulia gigantic chain—the Mangahao the broken body a pile of matchwood, catchment area. The steep descent to The driver of this vehicle escaped j u,,-, valley is made by a narrow bush miraculously with a bruised hip. There j track. Roadmiiking further than the was something for congratulation on , top of Ir|C , flirt was plainly impossible, ' the day of this accident, however, by j s 0 the famous.jigger line; was install* the people of the camp. Tho child- I cd alld bv mis all goods are let ren, who live at some distance from | aown and hauled up on a gradient the school which is held in the ! MO s teep lliat from the opposite sid-j IJI.C.A but', aro every morning and of the val i ey n looks perpendicular, evening aivCn a lift rry ,il - driver. On Joyri< u ns on the "jig" is strictly fortbis oceasio.ii however, ho had been b j d(JeUj which some dare-devil spirits forestalled by auoll'.er tj-uck which regret t e d, Only sick men unable to preceded him. J £ the Urn children who aefiot j ate the arduous track aro usually travelled by Jl bad been in the I th!S t]mll and then, of ill-rated vehicle, the camp may have £££*£ are in a 0 to apr.au to mourn ancthvi- tragedy, even >- . ' - inorg poiguaat than that of the tunnel, »2««« «• fi B „ eo id A in which seven men lost their lives. . .Only once in yea,

Public Works' man, "has the jigger broken loose. On that .occasion the rope broke and the down truck weighing a lon, dropped into the stream. No! nobobdy was near at the time, fortunately." DIVERTING THE STREAM. Two suspension bridges, one a very substantial affair, have been constructed over the stream, but before ' leaving the near side of tho valley, a visit must be paid to the other mouth of the tunnel that connects in a straight line, with Arapeti. M. is a mile long, and eight feet in diameter. An interesting object is the boiler which generates the power. This weighs ton tons ami the problem of transporting it was a ticklish one — but not beyond the resources a.nd ingenuity of the engineers. Just underneath the lirst bridge the stream has been dammed and the water diverted through tho by-pass tunnel, the construction of which took a year, and was a. most expensive, but necessary, part of the programme. Some water, however, still percolates through the fascine, ani a "naval brigade," on a largo armed with a powerful steam hammer, is engaged iu arising tour lines of steel piles to hold the water at bay should heavy rain bring a. torrent swirling down, which, avoiding lite legitimate outlet, wAI endeavour to rob the engineers of the fruits ol! their victory over Nature before the foundations of the upper dam can be laid. Up to the present. however, very little difficulty lias been experienced with floods. RAINFALL IS HEAVY. While we ar e on tho subject of floods, some statistics relating to the rainfall will be apropos. In 10-l the fall totalled 109.49 incites; in 1922 it amounted to 89.28 inches. while Hiat for the present year bids fair to eclipse both. From January to July the amount that foil was 04.15 Inches; 43.!U inches fell for the corresponding period last year. It :s to be noted Ihat the actual fall in the catchment area is probably heavier than these figures denote, a* the records were taken in a comparatively sheltered spot. DIFFICULTIES CONQUERED. As mentioned above, the same difficulty in finding a solid rock face has been exeprienced at the Mangahao darn as at Arapeti. The contractors disco-.<'-:-ed, to their est. thai what had appeared to be a solid rock face was but 20 feet thick and beyond that in the hill-side w;ts an old bed of the stream, which had silted up in the course of countless ages as the river wore out a new bed to the I eft. The. hill has been pierced to a distance of 200 feet on the one side, and i) feet on the other. Otto large wing-wall of the dam lias already been built, and when completed it wilt be 90 feet thick at the base, 100 feet across at tho bottom, and th'Jj water will be 9U feet deep, or 55 feet above the mouth of the tunnel, This reservoir will have a capacity ot" 500,000,000 gallons. As the plan indicates, provision j has been made for the construction | of another storage reservoir to hold | 050,000,000 gallons against periods I of drought, but it is probable that , this will not be found necessary, at ' any rate, for present needs, as the i potential power has been under- j estimated.

' question has been answered in other ■ districts. Take, for instance, that of the Thames Valley Power Board. The use of electricity around Jlatamata is general among the dairy farmers, approximately 7 5 per cent, using it for lighting their hemes. and outbuildings and for driving the milking machine, water pumps and separators. The Board has some 500 milking niuchine motors in use and is endeavouring to install another 100 before the coming season, lis ditiieulty is in procuring the motors, PROFITABLE INVESTMENT, l-'uimors there say that the advantage of electricity over ben*, ue is that the motor wiil start on tie. coldest morning, there are no fumes, and the plant is noiseless. There is also 'he advantage of the light iu tin sluHl for tho man who gets up before the sun. Somo say that electric power costs the farmer £5 per year more than the oil engine, and others tio, but it seems that the variation is chiefly due to the difference in efficiency of the engine. I'll general convenience and the absence of the co.it of carting the benzine, however, make electricity more proataine. A.ound '. e Aioha, 'lit custom is !o instal a healing point, with a control switch, in the milking shed to provide boiling water for washing up. When 1 lie milking is finished, the switch connects up the heating ap- j paratus anu the water is brought to j boil between milking hours. That is, when a farmer ceases milking in tr.ej morning, he uses lh e water that has I boiled during tho night, and at night I that boiled during the day. Thus, all | heating apparatus is cut out dur- ' ing tho peak load, i.e., during niilkingr hours. For £4 10/ per annum an abundant supply of hot water i.f available the year round. Power, again, is available throughout the twenty-four hours. Around Matamata some farmers have kept their engines as a stand-by, ready for use in case, at any time, the powei cuts out, but this has very seldom ! happened. A flat rate, based on ttie j quantity of butterfat produced is j charged. BENZINE SCRAPPED, '. A correspondent in the Matangi i district says that the use of electricity is practically universal, both lor lighting and power. "At the incep- i lion of the scheme many of the farm- j era, especially those with small herds, decided to slick to their benzine engines, believing that this would be a cheaper proposition, but to-day there is hardly one who has not had the power installed. The Central Power Board provides power for water j healing at a flat rate of £4 per a.n- '. nuni for i k.w.; to for :; k.w., and £S i foi 1 k.w. The i k.w., provides 14 gallons Of water practically boiling. This heating system will be very ' extensively used during the coming season. The charge for power is somewhat high at preesnt, but will be - reduced as the reticulation of the district is completed. { IMPORTANCE APPRECIATED. S Judging by these facts, it appears j safe to say that the .UauawatuOroua Board will hav e no difficulty in disposing of all the current it can get. Preliminary eanvassus have proved already thai the man on the laud :n this enlightened dislriel fully appreciates the importance, economic |,

TKANSt'ORT HEAVY ITEM. Transport is one of the heaviest items of expenditure in connection with this undertaking, as may readily be reckoned when it is stated that it cost the department about 20/by a steam shovel as fast as for eevry ton transported to Mangahao. and 17/- for every similar load as far as Arapeti. Consequently every effort has been made to use what materials are at hand. The hard blue stone from the tunnels has been saved and crushers are now utilising this in connection with the construction of the dams. At Mangahao, too, a fresh brings down quantities of fine sand which are scooped up it piles up against a bend o£ the river. Every penny so saved is a penny earned, but seems to be a mere drop in the ocean when one contemplates the ultimate cost of this mighty engineering feat. The manner in which the great engineering difficulties have been faced and conquered is a magnificent tribute to the engineers who will soon lie instrumental in bringing the "juice" to our homes, farms and factories. Another large shipment of poles for the Manawatu-Oroua Electric Power Board is now being unloaded from s.s. Oraima at Castlecliff, while the s.s. Ihumata was expected to arrive at Wanganui last night with a further quantity. NATURE'S GIFT. TO THE MAN ON THE LAND. POWER ON THE FARM. With the time fast approaching, when the Manawatu-Oroua Electric Power Board will he in a position to commence the supply of cm-rent, the question of rural use of electricity is one of general interest in the Manawatu. There 13 some question in the minds of many as to whether the farmers will take kindly to the new source of, po-wct. Let us see how the

and industrial, of the coining of the . "juice." An official of the Board told j a "Times" reporter that the chief obstacle to b C: overcome in approaching | a potential customer was the prevailing lac kof know-ledge as to elec- J tricity and Its uses. For instance, one j lady declared that she could not have • it in the house, she would be "afraid 1 of the lightning coming in." Again J some farmers had gathered exaggerated ideas as to the cost of installing the current. One got quite a shock when told that it would cost £lO to instal six lights in the house. He had put the figures at ahout £1C0! So far as the district, had been canvassed, about 90 per centfl of the residents had applied for current for electric motors and lighting. In most cases where farms were leasehold, the owner would consent to havingthe current put in as an improvement. SAVING FOR FACTORIES. It is probable that many of the 1 dairy factories in the Manawatu wMI ; eventually be run entirely on elec- ; tricity. It has been found that most; factories are keen on getting an electricity water heating system. The average fuel bill of a factory for the season is about £9OO per annum, whereas electricity can be supplied to the si,me amount of work for £350 to £2an. Jfighting and motors for driving churns and pumps will naturally be used by factories. It is. probable that must of them will take to electric lorries for collecting, charging the batteries at the factory I Uself, being quite a simple operation, j The Awahuri factory, for instance, ai--1 ready runs an electric truck from its own power plant. MILKING PLANT TARIFF. As regards the cost, the ManawatuOroua Board's milking plant tariff — I*s per h.p.—is lower than that of any other board in New Zealand. The meter system vail be used throughout. The Board considers this fairer than the flat rate, as each man pays exactly for what he uses . In the caee of the homestead which I £f£.uds hack from the road, the Board ) erects th 0 first chain of line on the consumer's property tree- ■i'Me-'

I thing over this distance is charged at ' cost price. Bach point in the house I costs 32/0 to 37/6. As to power inI stallation, wiring and switch for a 2 j h.p., motor in the milking shed will cost about £i . .-is tiie Board purchases in large quantities, and the price of material is tailing, it is proi able that the actual cost will be lower than at present. A 2 h.p. motor will b. sold at £ls complete. 'Thus, the motor and wiring can be j installed <'ir £2O. The charge j for lighting will be 3d per {unit wiiii a minimum of 5/ per month, and for healing and ironing,' Kid per unit. In the case of resid-. euces, one meter may be used. In this ' ease *.i- first nine units a month Willi ltd charged at Sd per unit, and tlte I balanc at 3id per unit,, with a minimum of 5/- per mouth. Water heating costs EO 10/- I".'!' annum for a 000 watt heater, if on a change over switch from a motor, etc., otherwise j at £l2 per killowa.Lt. There have been J many enquiries for bath heaters, For . cooking, it 2 k.w., range costs £2 per quarter and a 5 k.w., £.3. Three blocks ot the Board's district have teen ca.nassed and reticulat'.nn is progressing steadily. By the time the twelve months before the Mangahao current will be available have elapsed, there should be a strong demand for the whole supply. We ar e indebted to -Mr H. E. Paeey, managing iirector of Messrs. Nathan and Co., for intormation as to the uses of electricty in other districls, mentioned in this article. VISITING EXPERT. INTERESTING COMPARISONS. Mr. X. B. Merson, an Australian electrical expert, now visiting lJalnierslon North, states that the Commonwealth will never he able | to establish hydro works on tlie scale that has been possible in New Zealand oil account of the lack of a constant water supply of sufficient volume. Mr. Merson, who hails from Towns- j viile, North Queensland, was interviewed by a "Times" reporter this | week, and described the system which he installed for that town, of 30,000 | inhabitants. Tito pumping station for . the water supply was already at hand as a. power source, and thus the two authorities, water and light and power, became amalgamated. STEAM AND GAS. The two chief systems used in Australia, for generating electric power are steam and suction gas. Severs. small hydro plants have been established in Victoria and one in New South Wales. All the rest are worked on the other systems mentioned. For a small supply, '.hey can be i\uz\ very economically, but tho advantages o! hydro are unquestioned, particularly when schemes of the magnitude of those now completed or underway in New Zealand are concerned. | TOWNSV HJ.K'S LIGHT. ( The Towns.-,ip. municipal station, j said Mr. Merson, is situated tour miles j rrom the centre of the city, which is ' like Palmerston North in the physiography of the district and tlte wide area over which the capital of North Queensland is scattered. In the matter of power supply, too, the system* of the two districts ate veiy similar'

Th B town has never been a railway junction, but in a few years time it will be a junction of a highly important character. Here all the Now Zealand Government long distance i 110,000-volt lines will meet, and the sub-station could really be called the I "master switching' station" of the ' North Isand. There will be lines to I Maugahao hydra station, 24,000 h.p.; other lines to Woodvillo (branching off to Wairarapa and Wellington). while ' the main line goes on to, Napier. Wai- : karemonna hydro station, 40,000 h.p., Gisborne, Whakatane, etc.. I" Arapuni iiydro station, 06,000 h.p. Another line will leave Bunnythorpe, tip the Main Trunk line, via Tailiape, Ohnkuue, Tauniarunui, ere, while other lines will radiate to said Xarauaki, the latter line going up the West Coast to jein up near Te Kuiti, with 'the big liydro stations at Arapuni and Horahora (9,000 h.p.) lu the case of a break-down of one station, current can then be sent from others, such as Wuikaremoana to Wellington, Mangnhao to Waikato or Taranaki, Arpuxti to Wellington, etc. At Bunnythorpe the Power Board will buy its power at a pressure of 11,000 volts, and iHStal its own distributing equipment. Bines will radiate to Palmerston North, Feilding, Halcombe, Kimbolton, Pohangina, Ashhurst, Longburn, Kangiotu, Himitangi, Binton, Kongot'ca, and Sandon, etc. At various points of these lines, there will be erected outdoor sub-stations for transforming the 11,000 volts down to either 3300 vlts Cor further distribution, Or to 400 volt's and 230 volts ready for use in motors or lights. The 3300-volt lines will carry the power down the various roads, and col the sumo poles that the wires are carried on transformers of smaller sizes will b e erected to transform this high pressure to 400 and 230 volt's lor consumers. The idea of using- high voltages is to avoid loss in transmission and use smaller wires, as it is not economical to transmit 400 volts much over a mile or perhaps two miles. The cost of a big Copper wire for the powor at low voltage is a costly item, and the heavier the wires are, tho poles have to bo much heavier, and more costly in proportion. WAIMAKARIRI POWER SCHEME.

The Christchurch City Council, a a special meeting held in committee. received from Messrs. Churlus B. Hawiey and Co.. of Washington, I >.C. Ih-.dr full report en the proposo.il hydro-«leeuie development of the Wiiimakiriri River at Otarama Gorge. The report, was u most bulky doeumenl. and dealt exhaustively with ai: phases oi the tiuostton. The migin eens recommended n proposilio:, which would cost i'S3K,'!OO. and vvhicl' would ■ rovide an initial g-t-ncrailisfc' capacity of 35,0ne k.w., win, an in ci-etuw of --i,a"e k.w.. by the insinuation oi addii.io.iul uriuipinuni. and with a.u ultimate capacity o ; 1a,500 k.w., when provision was rtiadi for tho regulation of Hie stream now Th-i average annual chargrff v.-. re ■--■■• down at CH.o I .'' 1 . winch included a provision of for depreciation maiutciKuico, and repairs, and it wa: claimed that tin; demand for the current would . provide a revenue amph to meet outgoings, the cos! to the consuiuu' being considei nbiy less than the Gov-nunti.t charges-. Attached to the report wu* a long commentary by Mr B. Hitchcock.. General Manager, MuncipaJ Klcelrieity Deportment, Christchurcii in which tic slronglj indorsed th" scheme proposed bv ilie •mgin e-or.-i and rccomraendtd thai, they sbouid be invited to submit proposals for th-. preparation of designs and specifications of the complete plant. >oi tin under-wafer portion oi thu powerhouse, and for the terms '.:r:vri which they would act ai cvusu'.ing engineers sunervlw its erection.

Oroua district (including Palmerston North) a three phase alternating current is used, supplying 5000 volts high tension, which is broken down to 240 volts for light and 415 for power. Our informant mentioned also that the street lighting of Townsville was conveyed by a separate system ot wires (a constant current series), so. j that any breakdown did not affect do- , mestic lighting or vice versa. This j was a matter- which he commended to the careful consideration of the local j authorities. The treet lamps are of | handsome design, with four or two , globes. THE WHITE ANT ENEMY. I Several difficulties were experienced in installing the Townsville sen ice, ' which should not be met with here, j said Mr. Merson. The chief of these 1 was in connection wrth the hardwood ' poles, which were drawn from, the same district as that which is supply- ! ing the "Manawatu-Oroua Board's <5Ss- j trie. In Queensland, as in other parts of Australia, the white s.nt is the great enemy of even the most durable woods, and despite all. precautions, th e poles have to be renewed after a shorter period of service than they will give here. The poles, before th v y are erected, have to be imprefrnated with ceosote oil and arsenic, and anoth**- anti-ant preparation, is j applied after the poles are erected. I Constant vigilance is necessary, as It I2 1 impossible to tell at a glance which ! poles arc most likely to have been j attacked. I in "Tasmania, however, hj dro-eiec-tricity was developing rapidly. Oct large work haa already been established and there is ample water power tor many more. Mr. Merson intends to visit United Slates of America and Canada next year to .study hydro-electricity then-. N.Z. GOVBENMENT SUBSTATION. AT BrNNVTIfORFE.

On the. earl}- lithograuh plans of the counties, the part of Buimytharpe, Where the hotel.' Glaxo factor;-, etc., now stand, was"called "Mugby Junction." A route for a railway line 8,150 laid off to the Gorge oa the, planfi.