THIS AGE OF STEEL AND CONCRETE

Waikato Independent, Volume XLV, Issue 6231, 27 April 1949, Page 8

THIS AGE OF STEEL AND CONCRETE

(By “H, J,”)

That is hbV some" archspWgist of the future examining the rubble of today's civilizationr^-supposing 1 • uve. leave him enough of it to study—-Avill probably describe it. In fact we ourselves think of it as such, and rather pride ourselves oh the phrase as epitomizing what we feel to be “up to the minute.” Yet I think a man need be argumentative only to the degree of, say, two whiskies in the company of an architect, to contend that of all the materials man lias learned to bend to his art and crafts or with which he has sought to house his culture, among the newest is timber. Timber, that is in all its infinite vari- ' ety of textive and grain and shades of coloration, and with its endless adaptabil ity for processing, as distinct from mere trunks and boughs dragged from the forest. Right through history man lias built in brick and stone and mortar. His art\ has found expression in massive marbles or the pebbles that beneath his skill become scintillating jewels; bronze he has wrought, and silver and gold, then iron; ivory was his medium too and shell and glass, what time all the wealth of the forest meant to him no more tliaj some rough beams and planks, branches and twigs for thatch, sticks on which to stretch the skins or lean the bark slabs of a hovel, leaves to strew the flagged floor of .liis grim castle. It is only as the forests which yield it have receded before the waste and shrunk from the destruction of the exponents of metal and stone, that timber has come into its own as one of the materials essential to both the art and science of . this most modern age. But all that is a digression, no more than an ebullition of soda water from a solitary nip. . . . TIMBER AND POWER SCHEMES What I really want to talk about is timber in relation to the construction of a power scheme. Like me you must all have read articles quoting figures of tons of steel and yards of concrete required to build our own Maraetai station for instance. I can't reinember the figures, but they were intended to give the impression of an awful lot of cement and stuff; and that the thousands of pieces of steel laid end to end would stretch from here to 011, ever so far away. In short, the articles were meant to convey the idea that this most modern of all our hydro-electric powerstations was to be a sort of steel 'and concrete architeetual ideal made manifest, and built of nothing else. Now, I have a profound respect for civil engineers as a class and consequently I am hurt that they should betray my simple trust by trying to mislead me in that way. The plain fact is, of course, that the' predominant material necessary for the building of Maraetai is—wood. It looks like needing not le&s than twelve, possibly fifteen, .million feet B.M. of wood of one sort or another. I disdain the reinforcing steel expert's method of illusstration and will not bore my readers with a calculation of how far that timber ripped into 3”x l”s and put end to end would reach, but I know it would be three weeks by train and boat beyond the point where they left the last steel rod rusting by the roadside. Still, statistics arb fashionable, so here area few that strike me as illuminating from the standpoint of general interest. It may be as- ' sumed that somewhere about two thirds of the timber to be consumed by the Maraetai job will be pinus radiatar —say 8.000,000 feet B.M. At a log to timber conversion factor of 5 that will take 19j million feet of logs, and that again amounts to a twenty year’s crop off 550 acres of pine plantation such as faces Mangakino on the east bank of the Waikato. The other one third will be in indigenous timbers, chiefly Rimu. The average timber content of rimu trees being worked out of native bush in the Rotorua area at present is roughly 1200 feet per log. The recovery of sawn timber is about 70 per cent so that to give us that 4,000,000 feet we’ll need have means the death of nearly five thousand more of those splendid centuries old giants among the fast dwindling population of our lovely red pine. A sombre thought for all lovers of our native bush. Would that we could build in steel and concrete! * OBTAINING SUPPLIES A HEADACHE To obtain adequate supplies of timber, as and when it was wanted, for a hydroelectric construction scheme has always been a headache up to a very recent time .in the history of the Maraetai job. In the order of things it could scarcely have proved otherwise. Commencing with the urgent need to erect accomodation for the first workers on a barren site, through an ever increasing load occasioned by the building of cookhouses, offices, workshops, stores, schools, recre ation halls, and more and more houses and hutments; up to a peak with the demand for form -work at the dam and finally the powerhouse itself, the consumption of timber on one of these big schemes is roughly equal fitm first to last over a period of four years to the whole output of an average sawmill. On previous power schemes and in the earlier stages of this one, there was alternative to an endeavour to get the Works Department’s timber requirements through the millers or merchants already established in the trade and including the Railway Department and the State Forest Service. It is obvious that' if those services of supply, whether state owned or private enterprise plants, were operation efficiently they must have been at pretty nearly their full capacity, and ■jvith steady njarkets to absorb practically their entire production. Under circumstances it could scarcely be expected 1

that these concerns, already working at near capacity and commi.tteed in outputto their regular .customers, could smoothly nbsofb the .suddenly steeply increased and then abruptly terminated loads im . posed on them by the construction of a series of power schemes. At any rate in practice 'they,-never were able satisfactorily to do so! It is worthy of note in this Connection that away back in 1.925, when the timber trade was normal and though there were numerous mills working in the vicinity, - Messrs Armstrong Whitworth and Co., found it necessary to operate a small sawmilll at ' Wharepuhanga to bolster up inadequate supplies from the trade for their Arapuni power scheme contract, Karapiro was, of course, a war-time job with defence priorities claiming timber right and left, and warding off timi bor starvation there was a nightmare for hose concerned from beginning to end , of its programme. Indicative of the difficulty commonly experienced by the nor- , mal trading concerns in taking up the , timber requirements for a work of the magnitude of ours, it may be mentioned , that in early 1947 our orders for timber were distributed among no fewer than twenty nine firms as far afield as Rotorua, Tauranga and Taumarunui. Another feature from the point of view of maintaining a programme on the works was undue time lag in delivery dates. In spite of such pressure as could bo brought, to bear orders dragged on and on long after the programme demanded, that the materials should be on site. In many instances, such was the state of the market, no timber was ever received to our orders and ultimately, when our own sawmill gradually overtook the leeway as far as sawn pine .ivas concerned, long outstanding balances totalling nearly a quarter of a million feet were cancelled. Buying timber on a seller’s mark et out of scant surplus margins meapt too that control of supply rested at the discretion of the miller Or merchant in awarding priority among a. number of clamouring customers, and inevitably resulted in the Works Department having to accept undue proportions of low grade and .unseasoned timbers to enable it to carry on building at all.” . “COULD. HAVE BEAN 'DROWNED’” With the decision that Maraetai should be next in the chain of power schemes after Karapiro, a new prospect was opened up for consideration: Within the square mile Or so of valley to be flooded by the new lake was over 400 acres of virgin pj/nus radiata-plantation which had just attained its majority, that is to say it was old enough for use. Apart from certain technical problems involved, in view of the existing acute timber shortage throughout the country simply to drown those trees where they stood was unthinkable. The logging* rights • could be sold, but—couldn’t the Works Department turn all those doomed trees into the timber for which the job was already beginning to cry out? It was an enticing idea. Might it not mean an end to all that waiting and delay, to inproyisation and endless inconvenience? No more excessive freight and cartage far haulage from long distances when the timber grew at our front door? The Deuirtment as consumer able to decide its own priorities, and switch its plant at an hour’s notice to meet new needs as they arose? .... And so it was decided we should erect and operate ou r -own Sawmill at Mangakino. Shortage of skilled labour and n extreme difficulty in obtaining median ical equipment long delayed bringing the plant into production, and it was not until July Bth 1947 that the saws of one half of the mill working on a temporary rig whirred through their first log. Until the end of that year the crew, often working under difficulties, pegged away turning over about 6000 feet of badly needed scantlings or badly needed scant ling or boards a day to the waiting gangs of carpenters. Then, during, the holiday shut-down at Christmas, the mechanical installation was completed and, with the New Year, a crew built up to pull strength began really to saw wood. No more dependence on outside millers for rough sawn pine from then j on. Today the sawmill coperativc con- 1 bust party tallies out around about its i 20,000 super feet each working shift. Still | there remained the problem of fully ; dressed and moulded timbers for solu- , tion. The demand for weatherboards, tongue and grooved flooring, sarking, : match lining, and facings seemed in- | satiable. So attention was turned to , the equipment of a secondary processing mill with such plant as was procurable in the way of four cider planers and re-saw units. Now almost half of the gross sawmill output is being seasoned and dress- I through the secondary plant, and the extensive building programme visible on every hand in Mangakino is being fed 1 entirely from pine timber cut and finally processed on the works. A further move 'owards self-sufficiency of these later power schemes in their timber traffic to the plan now being put into operation to mill our own indigenous timbers to meet job requirements from logs transported direct from the native bush to our log -kids here. Nearly 200,000 log feet of rimu went through the saws in March together with more tlian enough pine to meet all wants. OWN'MILLING PLANT Long strides those from the day when every stick had to be wrangled for on a very competitive market. That was yesterday: tojlay operation of the Departments’ own milling plant at a norm of efficiency calls for a production figure considerably in excess of the local job requirements and a surplus is. therefore, available for export. The policy of the Department is to divert that to other of its own timber hungry jobs throughout the North Island rather than to sell to /

the public: Time marches on, and so we find a steady flow of commercial timber outwards away from Mangakino to such places as Trentham water-works scheme; Lower Hutt Plant Zone workshops ; Housing Division contracts in j Gisborne, Napier, Wanganui, Auckland jand other centres. The State Hydro- , Electric Department draws on our mill for much of its wants for repair and ■ maintenance, -whilst Land and Survey 1 Department is being helped along at the ! same time with various of its developriient. schemes. | But building "timber in Rimu or Pino is not all the story of the demand that the creation of a new powerstation in this age of steel and concrete makes upon the poem that is a tree: One thinks of our great diversion tunnel as essent j ially a thing of concrete faced rock, but thousands of Larch trees in the State forests around Waipa were felled to provide for the third of a million feet of wood that went into the segments and cants of its framwork. Here someone needs a beam of great length and strength combined with lightness, and for that we must spend dollars and buy Oregon Pine; over here is a heavy stress, and for that we’ll want Ironbark from Australia; Rata for power-pole cross-, arms; Birch in place of precious, almost unprocurable Tot/ara where durability underground is called for; Mangaes for a slender strut too tough to break; some Tawa for interior finishing work; Eu calvpt trees, long and‘straight; harrowed from farmer’s shelter belts for piles and trestling and falsework of all sorts; Hardwood poles for transmission lines, and so on —but wood, all of it just wood. And so, when we reflect on the enduring majesty of concrete in one of our big dams, or gaze up at the slender strength of a steel pylon with its festoons of insulators and trailing filaments of shining copper wire, let us remember too that still: “timber must go down the , river today.”