THE RANGITATA TRAFFIC BRIDGE.

Timaru Herald, Volume XXXVIII, Issue 2698, 17 May 1883, Page 8

THE RANGITATA TRAFFIC BRIDGE.

The Aehburton County Council, having practically completed the extension of the traffic bridge over th« Rangitatn, issued invitations to the members of tho (Jeraldine County Couueil, of (ho eovcral Road Boards in tho neighborhood, the Aebburton Borough Council, «nd others, to be present at a formal oponing of thobridgo at noon on April 23, and to purtako of a lunch in honor of the event at tho Bridge Hotel aftcrwiirds. Tho early moruing was beautifully fine, but about nine o'clock it began to rain, and this may have preyented some of those invited from attending, at any rate tho number of guests was not bo large aj was anticipated, lhe residents on tho Ashburton Bide of the rivor were well represented. Mr W. O. Walker, the Chairman, with Mr E. G. Wright, M.H.R., another prominent member of that body, with tho County Engineer, Mr Baxter, and the Secretary, represented tho Ashburton County Council. Soverol members of the Ashburton Borough Council wero present, and Mr J. Ivcss, M.H.R. for Wakanui, wag also among the gueflts. Tub Goraldine County Council were represented by the Chairman, Mr C. G-. Tripp, and Messrs J. O. McKerrow, J. Talbot, and A. Sherratt, aud the Seoretary, Mr P. W. Stubbs. Mr Dennistoun represented the Mount Peel Road Board, and Mr R. Irvine, tho present, and Mr 0. flherratt, a former, overseor to that Board, also attended. A number of settlers from tho immediate ; neighborhood brought up the number Co about fifty. Each party as they arrived proceeded to inspect the bridge, and Messrs Walker, Wright and Baxter took great pains to answer all enquiries. It will bo remombered 'that some years ago a substantial bridge

about 1000ft long was built over the ( river, spnnning tho whole of the regular und defined channel then existing. The pieie of thii bridge wore formed by sinking by tho pneumatic process ft pair of iron cyliuders 4ft in diameter, which when hunlr to tho proper dopth wero filled to llio top wilh concrete. The spans are of 60ft, and Ihn superstructure consists of a light lattice (jirdor of wrought iron, supporting a simple roadway of wood. Tlio abutments consisted of heavy walls of limestone, built n short distance from the banks of the river uhnu'iel, and from oich of them a long embankment was piled up with tho doublo object of forming a roadway leading to tho elevated bridge and of confining any waters that in times of flood might overflow the normal banks of tho river. In 1878 an unusually heavy flood occurred, which tho channel spanned by tho bridge wus unable to accommodate, the northern ombankment was completely swept, away, and for some time afterwards tho main stream ran quite clear of tho bridge. kilter the nriin current returned under tho bridge, but in times of flood a strong stream cours.d down on tho north sido of it. The work tho completion of whioh the parly were met to colebrste was tha extension of the origiual bridge over this newly-formed riverbed. There had been a good deal of discussion between tho Ashburton and Geraldiue County Councils, between whom lay tho duty of extending tho bridgo, as to tho character of the structure to be employed. Tho former, through n series of circumstances which need not here bo reforred to, happened to have had placed in their hands tho carrying out of tho work, and from a numbor of plans submitted to them by Mr Higginson, 0.K., elioso the ono which thoy have carried out, though Mr Uigginson himself declined to exproia approval of it. This design was looked upon with great disfavor on this side, tho river, on the ground that it was impossible to drive piles in such a riverbed, and that money could only be wasted in tho attompt. Tho ABhburton County Council, however, were confident that piles could be driven, procured them, 3nd have driven thorn. At first sovcral piles were broken. These wero found to be flawed, and it was ala'i asserted that, sufficient care was not exercised in the attempt to drive them. The Athburton Council therefore determined not to let tho work by contract, but to havo it done by day labor and under careful supervision, under which circumstances it was believed the- pilm could bo driven without mishap. The result justified this belief. The driving wns roguluriy taken in hand in the early part of 1881, and tho last pile waa in its place by tho end of February, 1882. Tho contract for tho superstructure was then let, and this work was finished within another year. Tho extension in constructed in eighteen spans of 40ft each. E>ich pier consists of four round iron piles, 38ft long and Gin in diameter, tho two outer ones haviag a slight rake or batter. Tho depth to which they uro driven varies according to tho contour of tho surface from 25ft to 84ft, but is in no eas.; less than 25ft. To the top nf euch pile is fixed a cast iron cap, having a flat head for supporting the capsil, and with fLitiges to hold it in place. The cap is formed in two sections, the circular portions making rather less than a whole circumference, eo that when bolted together as thoy are with five stout bolls ou each side, a good grip of the pile is obtained. Tho piles wero imported from Homo ; the caps were cast by Messrs Anderson and Son, Christchurch. Generally speaking the piles havo been driven very truo to line, the only striking exceptions being ono or two of those driven first, before experience in dealing with the peculiar nature of tho grjund had boeu obtained. Keating upon tho caps of each pier and secured to them by bolt?, is a capsil of ironbsrk, 12 inches square, and upon this corbels of kauri, aho about 12 inches square. The corbels bear a continuous girder of diagonal trussing, in kauri, 6ft lOin in depth, tied together with iron rods ljin and 2in in diameter, placed 6ft Bin apart. The height of tho piles, together with the capeila and corbels upon them, has been so arranged as to bring the base of tho girders to tho same lovel with tho lower edge of tho girders of the old bridge, giving the same depth of clear waterway. Thegmlors aroeonnocted by three sets of horizontal and vertical stays and ties to each span. Upon them rest stout creas beams, and upon thosp longitudinal joists bearing a road docking of 3in black birch planks. The roadway is 20ft wide, as on the old bridge, and is bounded on each side by a neat sheep-proof fence. The girders and all the under work has been well tarred, and the upper work painted white. Seon from a little distance tho whole bridge has a very good appearance. Looking at the bridge from below, the superstructure looks very substantial, but the slender piles seem diminutive and out of all proportion. Six inches of solid iron, however, though it does not make much show, possesses enormous Btrength, and there need be no doubt of their ability to support tho weight placed upon thorn, and to resist tho slight pressure of water »gainst them. In faot, their slenderness is one of their most valuable points, as offering so little resistance to tho stream, Bcouring action is not likely to be set up about them. Tho carrying strength of Ihe bridge has been subjected to one test, which is said to be a protty severe one. A mob of 2500 aheep were moved about and all over it in a compact body, and no sign of yielding or weakness was discernible anywhere. The general opinion was that the Aehburton County Council had very satisfactorily solved the problem of erecting a sufficiently substantial bridgo for a moderate sum. Tho only point in which weakness waß suspected is the north abutment, which is protected by some projections of concrete, but it was thought by a good many of those familiar with the force of the Rangitata'n current, that these are insufficient. Tho Engineer, however, pointed out that tho danger of tho abutment being attacked was slight, there beiDg now so much freo water-way. As the end of tho bridge is vory near the high north bank of the riverbed, it is possible that water will very seldom reach this abutment at all. The approach is not quite filled in yet, but a few days more will suffice to complete this. The total cost of tho extonsion is £6800, or only £400 above Mr Higginson's estimate, but considerably more than this above Mr Baiter's first estimate. This cost, however, includes a considerable sum spent in repairing the decking of the old bridge, a good deal of the plunking having decayed. Most of those likely to arrive having done so, the enremony of opening the bridgo was proceeded with. For this purpose a couple of tall slender cabbage trees were fixed to tho roiling of the bridge at the junotion of the uew and old work, and a couple of flags hung from those. Only about thirty persons wero present, and the ceremony was made as brief as possible, as a brisk rain was falling at the time. The Chairman of the Ashburton County Council, in a few sentencos, expressed his pleasure at being culled upon to perform the ceremony, and declared the bridge open. Ho then asked Mr Tripp, as Chairman of tho Goraldino County Council, to assist him, and that gentleman expressed his gratification at having his disbelief in tho pile system swept away by the sight of the finished work. The Ashburton Council deserved groat credit for tho plucky way they had faced the difficulty. Cheers were then givon for Mr Baxter, the Engineer, and the ceremony was concluded. About 1 p.m. an adjournment was made to tho dining-room of the hotel, where Mr J. Hinokley, (he licensee, had provided a capital luncheon, tho Ashburton County Council providing the wines and spirits. Mr W. C. Walker, Chairman of the Ashburton County Council, occupied the chair, having Mr 0. G. Tripp, Chairman of tho Goraldino County Council, on his right, and other members of this Council on his left. The vice-chairs wero occupied by Messrs E. G. Wright and W. Julien Jackson. About fifty guests sat down to enjoy the excellent entertainment provided. After due justice had been dono to this, the Chairman proposed tho health of the Royal Family, and this having been duly honored, he proponed the health of the Governor, coupling with tho toast the names of the Members of the House of Bepresentativea present, Mr E. G. Wright, Member for Ashburton, and Mr J. Ivess, Member for Wakanui. In doing so ho expressed regret that no member of the House for districts south of the river were present. The toast was drunk with mutical honors.

( Mr E. G. Wright, in roepcindiiip, eaiil Ilia Excellency the Governor wiib a man of large experience and broad views, und ono capublo of taking on activo interest in everything relating to the welfare of the colony. The people of New Zealand were extremely fortun»te in having a gentleman of such high qualifications to act a? Her Majesty's representative »mong them. In responding, als'> for the flouae of Bepreientativo-", he would only Bay that aa a whole, (he memoirs of the Ilouse wero an earnest, hnrd-working body of men, typical in fact o( the people of New Zealand ; and however much they might differ about party politics, their one desire was to promote the interests of the colony. Mr J. Ivobb added a fow romarks in reply to tho toast. MrE. G. Wright proposed the next tonst — "Buecesg to tho Hangitita Bridge." This, he thought, was an oocasion wh*n all might agree fo forget their differences and congratulate each other upon the successful issue of their endeavors to finish tho bridge and render it availablo to the settlers of tho district. Ab the Ashburton County Council hud been somewhat pertinacious in currying on tho bridge, according to their own views, in opposition to those of the Gemldine County Council, he thought it was only fair to say Hint the Aahburton Council wero nctua'ed solely be a desire to carry out tho work at the least possible coßt consistent with securing o serviceable bridge. Having in view many other useful works required within the County, tho Council wero averse to sinking a largo sum of money in supplementing the enormous expenditure which had been incurred in constructing und endeavoring to mflintain works to protect the old btructure over the river. Tho Chairmnn of (he Geraldino County Council had that day gracefully acknowledged that his former views respecting the bridgo wore mistaken, and that he waß satisfiod of the substantial character of tho work executed. He therefore thought the two Councils might now bury the hatchet, and he had no doubt that when tho Goraldine County Council wero called upon to contribute their halt' of tho cost, they would do it cheerfully. He would oouplo with it the name of Mr Tripp. This toast was warmly received and duly honored. Mr Tripp, in responding, eaid ho had been ono of the strongest opponents of the extension of tho bridge on this system, but he did nut oppose it without reuson. Trial piles had been driven by Government engineers, and piles wero condemned by them. They ««id piles would not do. The Geraldine Council felt bound to believe the engineers, and then no other courao was open to them but to oppoßO the scheme. I£o was sure Mr Wright and tho other members of the Ashburton County Council would siy they acted rightly. (Laughter.) However, the work had been done, and tho Ashburton Council deserved great credit for it, but he doubted if it would have been carried out bo successfully if it bud not been done under the superintendence of the able Engineer of the Ashburtoa County Council. (Hear, hear.) There had been groat judgment shown in driving the pile?. Ho did not. bolieve the Government could have driven them. (Laughter.) The bridge was not quite finished. If. wanted the finishing stroke put to it, but that finishing stroke meant a great deal. The Engineer would agree with him that the north end of the bridge must, be strongly protected. £10,000 worth of protective works had b?en carried down the river, and thero wib no saying when bis floods might como and endanger the north abutment. He could not answer for his fellow merobora of tho Goraldine County Council, but he would do hiß best to get half the cost of the bridge paid by Gcraldine. He would suggest that a certain sum in reduction of the amount might be obtained from Government under the Roods and Bridges Construction Act. Mr Wright said it was too late to apply for assistance under that Aut. The work was now finished ; hod it boon about to be commenced, there might have been a chance of getting something. Mr Charles Harper proposed the " Health of the memborß of tho two County Councils." Ab an independent settler on the plains, unconnected with either Council, he would say it was a matter of great satisfaction to the settlers to have the bridge completed. They did not care whether the piles were bit inches or six feet through, bo long as thn top matched all along. Ho was surprised, and more than pleased, to find the new portion very much firmer than the old. He had driven | across three times, and oould tell with his j eyes shut when he got off tho new part on to the old by the increase in the vibration. The two districts and their interests were now united aa they ought to be. The Ashburton settlers could ask the other sido to supply them with timber ; and in return could offer to them, free from riak, tho Tinwald and Ashburton markets for stock, which wero second to none. The bridge was a most important thing for both sides, and it did not matter who paid for it. Ho hoped tho hatchet, as Mr Wright had said, would be properly buried, aDd that the bridge would furnish the means of frequent personal communications between the two Councils. Ab to the subject of his toast, he could say for the Ashburton County Council that they wero the beßt Council in the colony, and they had done some of the best work in the colony. It was worth while to take a ride from that bridge to tli9 Hakaia to Bee tho amount of water they had brought over the plains, enabling land to bo taken up and people to build and settle down where it would havo been impossible to nettle without the water. He expressed his pleasure that the Geraldiue County Council were taking up this matter of wnler supply and hoped they would persevero in it. He also hoped to see tho Ashburton Council next take in hand the irrigation of the plains, so rb to bring out all their fertility. Ho was sure it would pay extremely well. He oaupled with his toast the names of the Chairmen to the two Councils. Mr Walker, in replying on behalf of the Ashburton Council, referred to the construction of the bridge extonsion as a very diflioult and responsible job, because, as they undertook to do it, it had been condemned by professional men. They, however, took tho advice of the 'best professional men in New Zealand, and they took into account two most important matters in the interest of the Council, economy of funds and efficiency of design. They considered it waa their duty, not only to their own County; but also to the Geraldine County, to study both economy and efficiency. He hopod they had not been mistaken, and that none of them would live to seo any of the piles washed out. He thought that whether they looked upon the bridge as a thing of beauty or as simply a thing to go over, they had reason to be satisfied with it. Mr Walker then referred to the water Buppließ provided by the Ashburton Council, and said they were pleased to have been able to provide them, but no particular credit waß due to them. The Council had the work placed bofore them. It was not a great work, but it had to be begun, and now he was glad to say enquiries how to proceed with such work were coming in from all parts of the colony. In Hub work, as well as in tho construction of tho bridge, they were fortunate in having the assistance of so experienced and practical a man as Mr Baxter. (Applause) He thanked them heartily for the oordial way the toast hod been drunk. Mr Tripp had said his say in favor of the bridge, and having to speak now as Chairman of the Geraldino OouDty Council he waa reminded of another view of the matter. There would be a little bill coming in to them soon, and when that account was sent in o rato would most likely have to be struok. The bridge having proved a success, however, he hoped there would be no objection to a rate. Nothing oould be dono without money, and money was not only wanted for this, but also for irrigation. He had heard that tho Aahburton County Council had spent £17,000 on 700 miles of raoe, or about 6s per ohain, including head works. That was not a ruinous rate, and he hoped the Geraldine County Council would follow the example of their neighbors. Mr J. Ireis proposed the " Health of the Road Boards in the two Counties," coupled with the names of Mr Dennistoun, of the Mount Peel Board ; Mr Talbot, of tha Temuka Board ; and Mr Jackson, of tho Mount Hutt Board. Mr Dennistoun, in replying, spoke of the great advantage the bridge would be to the neighboring dietriot and the whole of South,

Canterbury. An nti'inuou* quniiti'.y of si. /ok passed over tho river every year, and ils extension would greatly facilitite their movements. Ho had disbelieved that piles could be driven, but they had been gob down, and now all that remained, he supposed, was to pay Tor them. Mr falbot, in his remarks, and referring to the opposition of tho Ger.ildine ratepayers to tho use of piles, eaid they had nevnr disputed the desirability of bridging tho river. They disputed that it could be bridged on tho plan proposed. The Chairman of tho Geraldine County Council had Buiii he w»b satisfied with the work. He (Mr Talbot) was not engineer enough to tay whether if. was Bati«f lo'ory or not. So fur as being a thing of beauty, it might be admitted at once to be satisfactory, but its stability had yet to be proved. They Imd heard over and over again, that the bridge could not be built on this plan, but then the same thing had been said about other works that had been spoken off, and which were carried out. It was eaid tho Hakaia Muld not bo bridged, but Mr White bridged it. It wbb said cheap railways could not be made hero, but Mr Wright had made them. And now it was rery poeeibln that the Ashburton County Council had doue what they proposed, in spite of its beiDg eaid that it. could not be done. (Hear, hear.) He thought that the Government, pven though they did not return to tho old subsidy system, might very woll subsidise works of this kind, which were of more than local value. Mr Jackson, in tho course of his reply, urged the Ashburton County Council to undertake tho formation of roads leading to the bridge as their next work. Mr Tripp proposed the health of tho Engineer, Mr Baxter, and the toast waa drunk with much enthusiasm. Mr Baxter thanked them for receiving the toast, bo kindly. The echeme of the bridge extension, ho Bhould etalo, was initiated just before he entered tho service of the ABhburton County Council, and it only fell to him to make certain uiodiQoatious in the plans and supervise the work. Owing to circumstances which could not be controlled, the execution of the work had to bo done step by step. The delay might have caused the public some inconvenience, but it was necessary in order tn keep the expense within reasonable limits. Tho total cost was £6800, half of which might be set down for the ironwork forming tlio piers, and tho other half for Hie superstructure, iie thought the cost could not be coDßideredexcessive,espccially as tho river-bed was generally considered to be impenetrable. Sceptieismon that point had probably vanished by this time. As to the carrying out of the work, he had found his charge an anxious one at times, but an engineer's life cansisted in a great measure in overcoming difficulties, und it had given him no email pleasure to successfully fill up the g*p in tho bridge. The success of tha work was largely due to the carefulness of the men in the working department, the foreman of tho pile-drivers, the contractors for the superstructure aud Mr Munro, tho inspector. As to what had to be done to the north end of the bridge, they would remark thnt less protecting w>rk than before would be required, because there was now so much more water wcy under the bridge and less embauktuent to pile up the water. A few other toasts followed, and the party broke up about three o'clock. Tho gentlomen from Ashburton started immediately, in order to catch the Express train at the Hinds, and the rest went their several ways soon after. All expressed themselves pleised with their trip, notwithstanding that its enjoyment was so much decreased by the unfavorable weather.