Sir Truby King Railway Bridge

Tahakopa River Near 85 Harrington Mill Road, Tahakopa

  • Sir Truby King Railway Bridge, Tahakopa.
    Copyright: Heritage New Zealand. Taken By: Don Sinclair. Date: 3/06/2017.
  • Sir Truby King Railway Bridge, Tahakopa.
    Copyright: Heritage New Zealand. Taken By: Susan Irvine . Date: 11/12/2017.
  • Sir Truby King Railway Bridge, Tahakopa.
    Copyright: Heritage New Zealand. Taken By: Susan Irvine. Date: 11/12/2017.

List Entry Information

List Entry Status Listed List Entry Type Historic Place Category 2 Public Access Private/No Public Access
List Number 9727 Date Entered 22nd May 2020 Date of Effect 12th June 2020

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Extent of List Entry

Extent includes part of the land described as Legal River, Otago Land District and the structure known as Sir Truby King Railway Bridge thereon. (Refer to map in Appendix 1 of the List entry report for further information).

City/District Council

Clutha District

Region

Otago Region

Legal description

Legal River, Otago Land District

Location description

The centre of the bridge structure is at the following NZTM coordinates: E1322482.4701648178, N4842163.54199683

The bridge crosses the Tahakopa River, approximately 1 kilometre south of the township of Tahakopa.

Summaryopen/close

Shrouded less by the mists of time and more by trees and moss, Sir Truby King Railway Bridge was built between 1922 and 1923. One of the few private rail lines in the country to be built to New Zealand Railways’ standards, it enabled government wagons to travel from the Tahakopa Station directly to King’s sawmill. The former Railway Bridge has aesthetic, technical, social and historical significance as one of a handful of original timber Howe truss rail bridges still extant in New Zealand. It also stands as a last testament to both the man and his largely unheralded adventures in Tahakopa.

In 1906 King purchased farm land in Tahakopa. His endeavours focused first on the farm and related ventures. In 1914 King made plans to establish a sawmill to take full advantage of railway access and promote the area’s economic and social development by investing in local businesses. In 1916 he began work on a rail line running from the sawmill, across the Tahakopa River, to the station a short distance beyond. Truby King built a steel line to a national standard so that New Zealand Railways (NZR) would allow their wagons to travel on his private line direct to the mill. In this way, double handling of timber would be eliminated and business efficiencies achieved - in any case, King never did things by halves.

The first railway bridge, built around 1916 as part of the private line, was rebuilt between 1922 and 1923. Built to NZR standards, the bridge was a Howe truss design and constructed of Australian hardwood. King considered the new bridge a very strong point in the businesses’ favour.

In 1929 Truby King closed the sawmill - after only six years of use the bridge was abandoned. The sawmill and other structures relating to his endeavours in the community were disassembled and removed or demolished. Only the bridge remained. With no owner to maintain it, the bridge eventually succumbed to the surrounding bush.

In 2017 a group of locals set about reclaiming Tahakopa’s history and its unlikely link to one of our national icons. Determined to raise the former Sir Truby King Railway Bridge to prominence, it is intended to be the main attraction of a picnic area, walkway and accompanying carpark. It may not be revolutionary, it may not claim the national spotlight, but perhaps Truby King would be pleased that his Catlins memorial is his very own Railway Bridge.

Assessment criteriaopen/close

Historical Significance or Value

Truby King’s activities at Tahakopa were extensive. While his achievements are still remembered in Tahakopa, there appears to be almost nothing physical left to testify to the enormous impact he had in the formation of this small township. From farm, to dairy, to school, to sawmill, to community structures and events, to transport routes and beyond, Truby King helped create a vibrant community. While his bridge is now redundant, it has historic importance as a last testament to the tremendous scope of activities that Truby King undertook in the Tahakopa Valley.

Aesthetic Significance or Value

Sir Truby King Railway Bridge has aesthetic significance. Although created for functional, rather than decorative purposes, the symmetrical appearance and large cross beams of the truss bridge are pleasing to the eye. The use of timber is also a natural and pleasing aesthetic. Now that the bridge is in a dilapidated state with greenery softening its edges, it has aesthetic value as an inherent part of the river and pastoral surrounds.

Technological Significance or Value

The bridge also has technological value as a rare remaining example of a timber truss bridge. It is evidence of the popularity of Howe timber truss bridges in New Zealand and internationally. The engineering technology of chords, timber compression members and iron rod tension members is still readily evident in the structure. Given that many timber truss bridges have been dismantled, or simply rotted away, very few now remain in our landscape.

Social Significance or Value

Truby King’s timber truss bridge is a local landmark in Tahakopa and has a social value to the community. In the same way that the old railway station is often a local heritage landmark, so is the old rail bridge. It contributes to the local community’s sense of place. While increasingly hidden from view, it has not been forgotten as evidenced by continuing local community efforts to promote public access and ensure its conservation.

(a) The extent to which the place reflects important or representative aspects of New Zealand history

Sir Truby King Railway Bridge represents the history of early twentieth century railways and sawmilling in New Zealand. Sawmills, by their very nature, were temporary, crudely-built structures not intended to last the test of time. And they didn’t. Of the some 180 mills that existed in the Catlins, none appear to remain. For practical and economic reasons, sawmills sprang up around rail stations and it is the relics of the rail transport system which speak to the history of the sawmilling industry. Most sawmill bridges were amateur efforts built to serve temporary purposes. In contrast, Sir Truby King’s bridge was one of the few private bridges built to specific NZR standards.

(b) The association of the place with events, persons, or ideas of importance in New Zealand history

Sir Frederic Truby King’s public image is one of an indomitable pioneer and reformer; energetic, enthusiastic but also muddle-headed, careless and disorganised. Stories abound of his changeable opinions, his forgetfulness and erratic behaviour. In an interesting contrast to this accepted view, Sir Truby King’s correspondence concerning the running of the mill and the building of the bridge show a very different side to his character. He is characteristically active and interested, but there is no sentimentality over the mill or its staff. He is clear, level headed and business minded. He is collegial but still directorial; at times patronising, hierarchical and a little unlikeable. This is the hidden side of the man who is one of our most beloved national icons.

(c) The potential of the place to provide knowledge of New Zealand history

Sir Truby King Railway Bridge provides evidence of the importance of the transport network in New Zealand - ‘Bridges, with their strong visual characteristics and evidence of technological changes, are a constant reminder of the importance of communication structures in the history of civilisation’. Without the arrival of the rail at Tahakopa in 1915, which Sir Truby King helped champion, a sawmill would have been impossible to run productively. All over New Zealand the arrival of the railway saw private lines established so goods could be carried straight to the station. The bridge was an integral part of Truby King’s sawmill line - a rare remnant in an age where there are few vestiges of private rail lines remaining.

(e) The community association with, or public esteem for the place

In 2017 to 2018 interested community members petitioned Council, Department of Conservation and other relevant organisations to recognise the importance of the bridge, promote public access and ensure its conservation. Their aim was establish a walking track and to turn the area around the bridge into a picnic spot and promote the story of Sir Truby King and the bridge to the tourist market. In September 2018, a local farmer gave permission to use his land on the south side of the river bank to provide public access. The submissions received additionally provide a strong indication of the esteem with which this place is held in the community.

(j) The importance of identifying rare types of historic places.

The longevity of Sir Truby King’s bridge is all the more important given that it is a rare example of part of a private rail line established to support a local industry and is believed to be the sole example of its type in Southland.

Summary of Significance or Values

The crucial role bridges played in the development of New Zealand is generally overlooked. Yet ‘the history of New Zealand engineering is the history of New Zealand itself…the development of roadways, [and] railways… has represented the development of the nation.’ Bridges also played a pivotal economic role in our nation’s history – even more so for the private companies who built tram lines and bridges to transport everything from logs and coal to butter and cheese boxes to market. Most of these tramlines and bridges were temporary, fit for purpose structures and have not survived. Even most government-built timber bridges have not survived the rigours of time and modern needs. This makes Sir Truby King Railway Bridge all the more special – it appears to be a lone surviving example of a Howe truss timber bridge, built by a private company to NZR specifications.

What elevates this bridge to one of special heritage importance is its association with Sir Truby King. A national icon, Truby King is legendary not only for his achievements but for his enthusiasm, changeable opinions and disorganisation. Yet Tahakopa and the Lauriston Timber Company reveal him to be a clear headed, decisive, organised businessman – a very different side to the man to that is presented in the literature. Yet Truby King’s many ventures in the Tahakopa Valley – farming, housing, dairying, roading, community buildings and events, promotion of the rail terminus at Tahakopa – have all been swept away by the passage of time. In the same way one war memorial can honour thousands of hearts, minds and deeds, so Truby King’s railway bridge stands as a memorial to the man himself, his outstanding efforts and the founding citizens of Tahakopa.

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Historical Narrative

Māori Occupation of the Catlins District

Today, Kāi Tahu mana whenua is recognised over a large part of Te Wai Pounamu. In Murihiku (Southland) the early tribes of Hāwea and Rapuwai eventually intermarried with Waitaha and Kāti Māmoe, who were gradually incorporated into Kāi Tahu in the 1800s. Hāwea, Rapuwai, Kāti Māmoe and Waitaha whakapapa and shared occupation are always acknowledged.

Tāhaukupu (Tahakopa) is an isolated part of eastern Murihiku south of Owaka. The bush, the rivers and sea provided rich resources for Māori living in the area. Mahinga kai and nohoanga are common along the coast with evidence of moa hunting in camps at Tāhaukupu (Tahakopa) Bay. The Tāhaukupu (Tahakopa Estuary) is a significant waterway. The Tāhaukupu River has its origins in in Kā Pukemāeroero (Maclennan Range), a place where māeroero (metaphysical beings) lived in what was heavily forested with rimu, totara, miro and matai. Southwest of the mouth of the Tāhaukupu River are the Tautuku Native Reserve (result of a Native Land Court Award 1868) and the Tautuku and Waikawa South Island Landless Native Reserve (SILNA) lands.

Dr Frederic Truby King (1858-1938)

Born just prior to the gold rush that set Otago a-light with immigrants, energetic, charismatic, enthusiastic and curious, Truby King was not content to confine himself to revolutionizing the care of the insane at Seacliff Mental Asylum, nor that of the nation’s mothers and infants through his Plunket Society. Truby King needed a business venture.

The Kings had been impressed by the beauty of the Catlins when on a camping trip in 1893. As Mrs King wrote at the time ‘the scene is altogether too beautiful for description…The Doctor is looking and feeling very well indeed, and he says he has never enjoyed a holiday so much’. Born in New Plymouth, Truby King referred to the Catlins as a ‘second Taranaki’ from the dairying point of view.

In 1906 Truby King bought Mr G. Scott’s farm in Tahakopa - a land area of some 750 acres. This was the beginning of land holdings which would eventually consist of six farms and a whole new field for his endeavours - from dairying to a technologically-advanced milking shed, to providing his own electricity.

Truby King also joined the Catlins-Tahakopa Railway League to help push the railway through to Tahakopa. In 1913, when the government proposed to change the terminus of the line from Tahakopa to Papatowai, it was made clear that Truby King had brought land in Tahakopa, and decided ‘to throw in his lot with them’, on the understanding the rail line would reach there. Truby King had plans for Tahakopa and a railway service was essential.

Truby King’s sawmill

In 1907 Truby King became part owner of an old saw mill in Tautuku, near Tahakopa. He was convinced that the timber industry would provide a ‘great impetus’ to the Tahakopa Valley – ‘What the district needed was the railway and population and live, energetic development…[with] the expansion of the resources of the valley conducted on modern, progressive, systematic, and scientific lines’. In mid-1914 Truby King made preliminary arrangements for the erection of a sawmill at Tahakopa. By 1915 he had leased land from the Government with a license to mill timber. His own holdings also covered 1,500 acres and most were in bush.

In February 1915 the line to Tahakopa was officially opened. Truby King’s efforts as part of the Railway League had been rewarded, and his enterprises could now take full advantage of the proximity of the railway.

In July 1915 the Lauriston Timber Company was registered as a private company to take over ownership of the sawmill. It was a family affair, with Truby King the largest shareholder, followed by his brother Newton King (1855-1927) and Dr Sydney Allen (1878-1960). Syd, as he was known, had worked briefly for Truby King at Seacliff and married King’s niece. Newton took ‘an active and practical interest, perhaps keeping brother Truby’s excesses somewhat curbed’. In May 1916 the Clutha Leader noted that the Lauriston Timber Company was not yet ready to start operations but was not far off.

Lauriston Timber Company sawmill, still known locally as Dr Truby King’s mill, was heralded as one of the largest and most modern mills in the Catlins. After the mill opened, the Southland Times described it as ‘one of the most up-to-date that has been erected in the dominion, everything connected with it being of the very latest and best’. The Clutha Leader wrote the mill was ‘well and substantially built, providing ample room and containing all kinds of labour-saving appliances’. Mill manager, Mr McDonald, also invented a widely lauded overhead log haulage system to deliver timber from the milling site to the sawmill. Producing over a million super feet of timber annually, it was one of the larger mills operating in the area.

Truby King’s correspondence show a detailed interest in the sawmill, its costs and expenditure. He dealt with the mill ‘in a business-like spirit’ but also collegially - ‘I want you to help me form sound conclusions as to the best course’. His involvement was not only managerial but practical – for example, popping in to Wellington’s Railway Department requesting type D tyres for their loco.

The first bridge

In February 1916 Truby King asked the Clutha District Council for permission to lay a steel tramline for sawmill purposes, across the district road and the Tahakopa River. Truby King’s plan was for NZR wagons to be hauled from the Tahakopa Railway Station along a private siding directly to the mill site, where logs were loaded and then taken back to the Station. This was more efficient than loading and reloading from private wagons. In March 1916 the Company called for tenders for the formation of the tramline.

The NZR ‘loaned’ ganger A.T. Heydon to supervise the building of the line to the standard railways plan. It was one of the few private railway lines in New Zealand built to the NZR’s satisfaction. Chapman notes King’s construction was more rigorous than the norm, “Unusually, the railway lines were steel, not the wooden ones of less ambitious mills.” This meant the lines were suitable for government railway wagons. He also purchased a second hand loco from NZR to haul their wagons.

In February 1917 the Clutha Leader noted that the ‘Lauriston railway, which leads from the terminus to the sawmill, is being pushed ahead, more than half the distance having rails and sleepers laid down, while a start has been made with the ballasting.’

Little is known about the first bridge taking the line across the Tahakopa River. It was no doubt of timber construction. It was also a sturdy edifice - during the June 1917 flood which washed away other sawmill’s bridges, Truby King’s railway only had some ballast displaced.

Truby King and Tahakopa

By 1915 Truby King was the ‘principal employer of labour in the Catlins district’. As King ‘set about stamping his manic personality on Tahakopa’, he built 24 rent free houses and single men’s quarters for his sawmill employees - to ‘a considerably higher standard than elsewhere’. Truby King also offered prizes for the best kept house and garden – the more children in the home, the bigger the prize. Employees were also supplied with milk fresh from his farm and free medical care from the doctor - he visited everyone in the settlement on his trips ‘from babies to bushmen’.

It was always a great day when he arrived, and no little child ever knew what would emerge from those bulging pockets, from boiled lollies, to sausages or toys.

Truby King was also the founder and president of Tahakopa’s first industry – the local cheese factory. On his farms, he built the most hygienic and up-to-date cow byre in the South Island. He also brought his Seacliff patients to Tahakopa to work on the farm. He and daughter Mary spent school holidays thinning out rows of turnips.

Truby King supervised the design and construction of the new school, donating timber from the Lauriston mill. When the community decided to build a hall, Truby King donated the timber. His local advocacy extended to consistently petitioning the Council to improve local roads and offering to contribute to the cost.

Truby King, company manager

Although King was one of three Directors, he took the lead – ‘leave it with me to decide finally what to do. I want your help and advice, but I think you will realise that it will be best to leave me a free hand’.

By 1922 the Lauriston Timber Company’s affairs were in disarray. There was perceived mismanagement at the Tahakopa mill and the Dunedin office. Truby King declared the Company Secretary’s condition as ‘bodily and mental failure – euphemistically described as a nervous breakdown but really, I should suppose amounting practically to insanity’. Meanwhile the Company’s salesperson had a ‘disobliging attitude to…customers…No doubt this was partly due to his being almost stone deaf, and unable to use the telephone’.

No orders had come in and timber was not being sold: ‘I don’t suppose it is fair to blame him [the Company Secretary] for all our troubles but he has been with us from the beginning and we have never done any good… I was astonished at the accumulation of timber’. Truby King offered to take a few thousand feet of stockpiled timber to use at Karitane – but only at a 33 per cent discount. Yet, despite the many struggles, Truby King remained optimistic: ‘I have always believed that we would make a success of the Lauriston Company, and I am satisfied that we will’.

The new bridge

In 1922 Truby King’s first bridge across the Tahakopa River was declared unfit for purpose. A local ganger inspected the bridge annually as the NZR ‘insisted that the lines be built and maintained to a quality standard sufficient to safely host their precious wagons’.

Truby King was not pleased – ‘in the absence of any facts or recommendations re rebuilding the main bridge, it is useless for the Secretary to ask what is to be done’. He asked the Secretary to obtain a quote, and then he would approach the bank for a loan. As the overdraft had been cleared and incomings were now exceeding outgoings, he reasoned the loan would be approved if the bank was approached with ‘clearness, confidence and reasonable optimism…’

The most common type of bridge in nineteenth century New Zealand, given our plentiful supply of timber, was the truss bridge - a structure of connected elements forming triangular units. Most New Zealand timber truss bridges used the Warren Truss, invented by Captain James Warren, a British engineer. The Warren Truss was used particularly for railway bridges.

Truby King’s new bridge was also a truss design – but not the typical Warren Truss. King used the Howe Truss design, which was commonly used in New Zealand for road bridges. American, William Howe, patented his truss design in 1840. It commonly had six bays (or panels) with top and bottom chords and diagonal members in timber, and vertical rods of steel. When used for rail bridges, the heavier loads required that the bottom chords were often made of steel rather than timber, although unusually in this bridge timber was used for the bottom chords as well.

For NZR wagons to be carried on the line, the new bridge had to be constructed to NZR standards. The Department ‘set high and uniform standards, achieving economies through standard design and construction details….’ Although the exact plan could not be identified it appears similar to the ‘New Zealand Railways, standard drawing, 40 feet span bridge truss (new design), A.A. Wrigg’. There are similarities between King’s bridge and three timber truss bridges built in 1920-1921 to cross the Akatarawa River, between Upper Hutt and Waikanae (all now demolished). Given the considerable timber milling in the Akatarawa Forrest at the time, they were built to the Public Works Department standard plan of 60 feet and 80 feet trusses, ‘designed for traction engine traffic’. Truby King’s bridge may have used the same plan, given its similar purpose. There are also parallels with several rail bridges built by New Zealand Railways that are still standing and in use, including the Mahinapua Bridge, 1905, on the Hokitika to Ross line, the Waimea Creek bridge, c.1905, on the Greymouth to Hokitika line and there are several others on the West Coast. Bridge 1 Rapahoe over the Grey River and the Arahura River Bridge, both with multiple Howe truss spans, have been demolished in recent years.

King was known in Tahakopa for always doing ‘the best of the best’ and his bridge was no exception. Constrained by cost, most post-war and depression bridges used local soft woods, and by the 1930s many were due for replacement. Even hardwood bridges built during the war years were deteriorating by the 1930s as the timber supplied was ‘not nearly as good as usual’. Truby King, however, insisted on good quality hard wood: ‘Not content with a makeshift bridge, he used imported Australian hardwood and constructed a magnificent edifice’.

According to local memory, Truby King ensured the railway line sleepers between the rails were placed unusually close together. Pedestrians could then walk across the bridge without getting their feet caught between the sleepers. The children of the sawmill employees used the bridge every day to walk to school and locals also made good use of it – thanks to Truby King’s forethought.

The new bridge was rebuilt between 1922 and 1923. The Company’s 1923 March balance sheet listed the ‘Re-erection of the Main Bridge, condemned by the N.Z. Gov. Railways. Dept.’ The total cost, including wages and sundries, was £338:18:8. It is likely that parts of the first bridge, including the steel rail lines and perhaps the timber piles, were reused in the construction.

Truby King considered the line and the bridge a ‘very strong point’ in the Company’s favour.

We have steel rails and locomotive handling Government trucks and every year’s work will increase our distance from the railway station, and therefore the length of tram-line that any competitor would have to construct…Yes, we are on a very good wicket indeed…it might cause comment on the part of some of our communities or Bolshevistic friends. They always forget the risk we have run, and the long, lean years behind us…’

The end of the line

At the time of the bridge’s completion, timber prices were on the increase. The Directors, against the advice of the sawmill manager, decided to establish a second smaller bush mill. The new mill’s first contract was supplying 80,000 feet of timber a month for six months for the 1925-26 International South Seas Exhibition buildings in Dunedin. By May 1925 the main mill was producing 73,025 super feet of timber worth £964. The second mill was producing 48,641 super feet at a value of £223. The Company was £400 in debt.

In April 1927 Truby King called a Directors’ meeting to discuss the future of the Company. He scheduled it for the same day as the ‘big formal Opening of the Plunket Society’s Hospital and the Emulsion Factory. Of course this will be a very busy day for me, but we can squeeze in an hour or two…’

Newton died in 1927. His last advice was to wind up the Company. Instead Truby King listened to the Manager’s pleas to leave it running- ‘when a man of his class is forced to conform against his will…he is very liable to fail’. If the Mill did not pay in three months, however, they would move to contract logging:

I spoke to the Mill hands, and explained just how matters stood. I told them that the question of whether they could look to the continuance of a good job with good wages and exceptionally good houses for their wives and families would depend on whether they could satisfy the Directors’…

Unsentimentally, King also reasoned they were likely to get a better price for the sawmill in summer.

On 16 July 1929 an accident saw the mill temporarily close. Truby King then instructed the Company be wound up. Although £16,000 was spent on the sawmilling venture in total, there was little profit left over for the shareholders.

Today, Truby King’s ghost has all but departed the Catlins. The mill closed in 1929 and the mill houses were moved to other places. …Only the railway bridge stands proud but bemused, bereft of railway line and shrouded by willows.

Reconnecting with the past

In 2017 a group of locals set about reclaiming Tahakopa’s history, and its unlikely link to one of our national icons. Determined to raise the former Sir Truby King Railway Bridge to prominence as a memorial to the innovative man who created such ‘a vibrant community’. It began with the creation of a heritage film about Truby King.

The bridge is intended to be the main attraction of a picnic area, walkway and accompanying carpark. The proposal for the walkway attracted $8000 funding from the Walking Access Commission to create interpretation panels to accompany this project.

Physical Description

Construction Professionals

A.T. Heydon (Supervising ganger)

Current Description

On the way to nowhere, Tahakopa is a destination rather than a thoroughfare. The casual tourist must travel serval kilometres on a narrow gravel road before emerging into the picturesque Tahakopa Valley. Past the popular ‘Pop-Inn B&B’, run by third generation Tahakopa residents, the traveller enters the main street of Tahakopa. To the right Tahakopa Valley Road leads to Tahakopa School. Unfortunately the school designed by Truby King was destroyed in a 1929 fire. Heading south along the main street, a few small cottages line both sides. Pride of place goes to the recently restored community hall. Built in 1921, the small timber building is called ‘Our Hut’. Starting out as a church, it was also used as a meeting place for the town and a polling station. In 2016 it reopened as a ‘heritage hub’; a place where memories of Tahakopa’s glory days of 16 sawmills and as a rail terminus could be kept and shared.

Moving south past ‘Our Hut’, the former Tahakopa Railway Station is just visible from the street. This once proud hub of the community is now is a state of poor repair. Opposite is the Tahakopa Memorial Hall, a timber and corrugated iron structure; it has yet to see the same restoration efforts undertaken on the Hut.

Continuing south, over the gentle Tahakopa River, there is a crossroads. To the east Tahakopa Valley Road continues past where Truby King’s cheese factory once stood. To the west is Harrington Mill Road which leads past the former site of Truby King’s sawmills.

Travelling west along Harrington Mill Road, paddocks line both sides. The river is shrouded in trees which line the banks. The bridge is invisible to the casual observer, but if you look specifically for the structure, a small glimpse is visible through the trees.

Currently, there is no public access to the bridge as the land either side of the river bank is privately owned. A small strip of Crown-owned closed road runs alongside the river and could be used to provide access to the vicinity of the bridge in the future.

Once the bridge is reached, it is still hard to see the structure – trees and bushes grow through and around it and mosses grow up and along the timbers. Small logs and sticks carried by the river are snagged amongst the tall piles. The bridge is no longer accessible from either river bank. Both abutments and end spans were removed when a flood swept away the road bridge and a local farmer removed them to shore up the main span of the bridge.

The main structural members of the bridge -- the top and bottom chords, the floor beams, diagonal struts, sway braces and the steel tension rods -- are all still in place, but the sleepers have gone. Local bridge historian, Donald Sinclair, records the close placement of the railway line sleepers ‘so one could walk across it without getting one's foot caught between the sleepers. The Mill school kids plus the general public of Tahakopa used that bridge every day to walk across it, so that's why the sleepers were set out like that.’

The truss is supported on piers at each end; these each comprise a series of four interconnected piles supporting a beam on which the truss rests; some of the original bracing of the piers may be missing.

Given the lack of access to the bridge, it is difficult to define its measurements with any accuracy. Timber truss bridges had a narrow carriageway - the railway line required a width of 3 feet 6 inches (approximately 1.7 metres). Neil Jenks, one of the bridge’s historians, attempted a calibrated orthophotographic exercise with waypoints using a 1948 aerial. From this, Jenks estimated that the decking on the bridge was originally 31 metres (102 feet) long and approximately 2.1 metres (7 feet) wide.

While the bridge is covered in shrubbery, more particularly on its southern end, it retains a sense of strength and stability. It does not appear to be under imminent threat of abandoning itself to the river. Forgotten and forlorn the still sturdy bridge is immensely picturesque, entwined not only with leaves but with the story of Truby King’s most unheralded adventure.

Comparative Analysis

The first truss bridge in New Zealand was likely built over the Hutt River in 1847. Early bridges, such as the Hutt Bridge, were built ‘using hand tools such as the adze, broad axe, hand auger and chalk line’. The Hutt Bridge also appeared to use the Howe Truss design. Unfortunately, it was badly damaged in the 1855 earthquake and was destroyed by a flood soon after.

Otago’s earliest truss bridge was likely designed in 1862 by John Turnbull Thomson when he was Otago’s Chief Engineer. It is a combined truss and suspension bridge with ‘an odd, massive masonry stepped pier…The whole concept was both odd and lacking in aesthetic merit’.

In New Zealand Howe Truss bridges were more commonly used as road bridges rather than for rail. A number of railroad accidents overseas, caused by structural failures in the Howe trusses, meant engineers turned to other designs for the strength and permanence required. Some major rail bridges were nevertheless built to the Howe truss design, among them the Rapahoe Bridge over the Grey River, 1898, and the Arahura Bridge, 1905.

For example, the Waitara River Bridge was a substantial truss bridge built for roading purposes, rather than rail. Constructed by the Taranaki Provincial Council in 1872; it was about 45 meters in length and served the community until 1913 when it was replaced.

Similarly the Stirling Bridge on the Clutha River, 1876, was an early road bridge. Employing shallow Howe trusses, ‘its opening was a grand occasion that was followed by a banquet in a nearby hotel’. The Stirling Bridge was replaced in the early 1960s.

Deep Stream Bridge, on State Highway 87 north of Clarks Junction, was designed by Robert Hay, an engineer in private practice. He designed a road bridge of two Howe trusses, each 30.5 metres in length. Completed in 1881, the bridge is interesting for its rare record of wages: a labourer was paid 7 shillings an hour; a bridge carpenter earned 12-14 shillings; and a blacksmith earned 10-12 shillings. All worked an eight hour day. Unfortunately the bridge no longer exists.

In contrast, the Balclutha Railway River Bridge was an example of a Howe truss bridge built as part of a rail line. Opened in 1878 it is known as the Blair Bridge after its engineer William Newsham Blair. According to architect and engineering historian Geoffrey Thornton, at the time it was the largest bridge of its kind in the South Island. It contained seven Howe trusses - in comparison to Truby King Railway Bridge which had one - and each were 36.6 metres long. Rather than timber piers, the bridge was supported on cast iron cylinder piers. Unfortunately the timber began to deteriorate and between 1966 and 1968 the timber was replaced with steel trusses. It is a Category 2 historic place (List No. 5207).

An example of a Public Works designed truss bridge was built over the Manawatū River. The Ngawapurua Bridge opened in 1885 and was a combined road and rail bridge with fourteen timber trusses. Like Sir Truby King’s bridge it had solid timber piers. It was replaced in 1965.

Private bridges

According to Patrick Hudson, author of Bridges of New Zealand, the country’s bush is dotted with the remains of private tram lines, and their bridges, that once carried felled logs to sawmills. When the tram lines had to cross gullies in the bush between the felling site and the sawmill, ‘trestle viaducts’ were built. The largest of these private tramway viaducts was the Percy Burn Viaduct in Southland. It was built in 1923 by the Rope Construction Company for the Marlborough Timber Company. It served two of the Company’s sawmills. Although not a truss design nor built to NZR specifications, it was built of Australian hardwood – Truby King’s choice of material. Standing the test of time it became part of a popular walking track but was closed in 2013 for safety reasons.

Another private tramway bridge was the Taringamotu Totara Company’s tramway viaduct. The Company operated from 1907 to 1962. They constructed a line that, like Truby King’s, was constructed to a high enough standard that the NZR would allow their wagons to be used on the line. This viaduct was built on the line around 1925, east of Taumarunui. One of the smaller variety of tramway viaducts, it stood about 18 metres high.

Perhaps the most impressive private bridge ever constructed in New Zealand was the Ongaroto Bridge. It was built by the Taupo Totara Timber Company between its base at Putaruru and sawmill at Mōkai. Completed in 1905, the combination arch, truss and suspension bridge was designed by James Fulton, a Wellington consultant civil engineer. The total span was 70.5 metres and was said to be the longest timber span in the southern hemisphere. The Company replaced the bridge in 1931 with a steel girder bridge.

The Cobden Railway Bridge was also constructed by a private company. The Point Elizabeth Coal Company constructed the bridge in 1898 over the Grey River to carry coal over the Company’s line to Greymouth. The Government took over the line in 1902. The Howe truss bridge survived until 2006 when it was replaced and demolished.

The Egmont Box Company built a ‘substantial all-timber bridge’ over the Hautapu River at Ohotu. Founded in 1906 by a co-operative of dairy farmers, the Company built butter boxes and cheese crates for local dairy farmers. It eventually branched out into the sawmilling business. The Company’s bridge, built between 1908 and 1911, had a lattice main truss of 45.7 metres. When the line closed in 1921, the Company dismantled the bridge.

Extant truss bridges

King’s choice of material has proven the test of time and his bridge is one of an increasingly rare breed: ‘Once numbered in their thousands, timber truss bridges are now becoming a rarity’. In 2012 the Rail Heritage Trust of New Zealand listed only 37 extant heritage rail bridges. Those built of native timbers often rotted and, as Geoffrey Thornton highlighted, maintenance was difficult because of the ‘nationwide lack of skilled bridge carpenters, and the difficulty in obtaining suitable timbers’.

An example of those that do remain is the Pakuratahi River Bridge which was built by the Government in 1876 as part of the Remutaka Railway. Like Truby King’s bridge, it is an example of a Howe truss bridge built as a rail rather than road bridge. Unlike Truby King’s bridge, one of the diagonal compression members is steel rather than timber. The bridge is now a footbridge on the 18 kilometre Remutaka Rail Trail.

Part of the old Nelson-Kawatiri rail line, the Kawatiri Truss Bridge is a Category 2 historic place (List No. 5148), 35 kilometres from Murchison. It was part of a branch line begun in 1871 linking Nelson to the main trunk line. Progress was slow and it was not until 1920 that the extension to Kawatiri was begun. The bridge likely dates to 1923, around the same time Truby King’s second railway bridge was built. The section to Kawatiri was completed in 1926. Work continued to be intermittent and the branch line never reached the main line. The service closed in 1955. Kawatiri’s railway station has now gone but its former site is a camping ground and the old rail bridge and tunnel are part of a short historic walk.

The Seaward River Truss Bridge is a Category 2 historic place (List No. 3745) and is a more recent example of a truss bridge. In 1936, the Government set aside £850 to build the 60 foot timber road bridge. In 1937 the tender of Lawrence and Manson was accepted by the Public Works Department. After its completion around July 1938, the Waipara County Council took over its ongoing maintenance. It is interesting to note that one span of this bridge was said to have come from the railway bridge over the Ashburton River.

Of all the comparative truss bridges, none seem to have the same combination of characteristics of Sir Truby King’s bridge – built by a private Company, for railway purposes, to NZR specifications and still extant as a visible reminder.

Construction Dates

Original Construction
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First railway bridge across the Tahakopa River is built

Original Construction
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Second railway bridge built

Construction Details

Australian hardwood

Iron

Completion Date

5th February 2020

Report Written By

Susan Irvine

Information Sources

Chapman, 2003

Lloyd Chapman, In a Strange Garden: The Life and Times of Truby King, Penguin Books, Auckland, 2003

King, 1948

Mary King, Truby King the Man: A Biography, George Allen & Unwin Ltd, London, 1948

Thornton, 2001

Geoffrey Thornton, Bridging the Gap, Early Bridges in New Zealand 1830-1939, Auckland, 2001

Other Information

A fully referenced New Zealand Heritage List report is available on request from the Otago/Southland Area Office of Heritage New Zealand Pouhere Taonga.