Canning Bridges - 2012 Booklet
Early Roads and Bridge Planning
It is interesting to note the comments of historians and others that the siting of Perth on the northern banks of the Swan River was a decision effectively taken in haste by Captain James Stirling during a reconnaissance visit to the Swan River area in March 1827. He decided that the location at the foot of Mount Eliza was preferable for the townsite because he considered it had better access to building materials, streams of water, and facility of communication. It is quite significant that the two other Swan River settlements – Fremantle and Guildford, were both south of the river, as was all of the early farming development and also the earlier King Sound settlement. It would not have been unreasonable for the capital to have been proclaimed south of the river, on the South Perth Peninsular. Since that time, and only really redressed by the planning initiatives of the Stephenson Hepburn plan and its successors, the economic and commercial development of Perth has been skewed towards the northern side of the Swan River.
So at the start, the river was the first real highway, with small boats and lighters plying between the ocean port of Fremantle and the inland ports of Perth and Guildford. Land cultivation was focussed along the river banks, and the combination of sandy soil and lack of community capital meant that a reliable road system would be a long way off.
During his stay at Cape Town while en route to Swan River in 1829 with the first settlers on the “Parmelia” and “Sulphur”, Stirling met and recruited an unemployed engineer/architect, Henry Reveley. On the voyage across the Indian Ocean, he was formally appointed the colony’s Civil Engineer by Stirling acting under his authority as Lt Governor. Reveley remained in this office until his resignation in 1838, when he departed the colony. He proved himself to be versatile and competent in both the architectural and engineering fields.
Early town allotment and building regulations were promulgated by Stirling and he appointed Land Commissioners for road and bridge construction, and “to assess on each house its proportion of the expense”. The first Land Commissioners were the Government officials, John Septimus Roe (Surveyor General) and George Fletcher Moore (Advocate General).
Very little was achieved by the Commissioners, and the state of the roads was a constant source of grievance to the early settlers. For many years town streets comprised ankle deep sand, were a dust nuisance, and were without footpaths. In 1837 Stirling reported to the Secretary of State for Colonies that:
“At the present time it can scarcely be said that any roads exist, although certain lines of communication have been improved by clearing them of timber and by bridging streams and by establishing ferries in the broader parts of the Swan River …”
It should be noted that only one substantial bridge was built in the Swan River colony during the first fourteen years of settlement, and that was the 1835 construction of a timber bridge at Drummond’s Crossing, across the Helena River at Guildford. When the water levels are low, you can still find remnants of this bridge behind the polo ground at Guildford on the old alignment of Drummond Street.
In 1838 new legislation was passed which replaced the Land Commissioners. It provided for the establishment of Town Trusts to manage roads, bridges and ferries within town sites; and outside of towns for roads, bridges and ferry management to be vested in a General Road Trust. However, George Fletcher Moore’s comment at the time was that “everybody wishes to have roads made, but nobody wishes to pay for them.”
Following Reveley’s resignation, Stirling downgraded the office of Civil Engineer to that of Superintendent of Public Works. He appointed Henry Trigg, a local builder, to this position.
The First Canning Bridge
The first Canning Bridge was designed by Henry Trigg in his position as Superintendent of Public Works. Tenders for this structure were first called in the “Perth Gazette” of December 26, 1846 but the prices were considered too high. Tenders were re called in 1849 and a contract was awarded to Solomon Cook. He completed the bridge in 4 months at a cost of £425 pounds. The bridge was 520 feet long and 12 feet wide, with a deck 8 feet above high water. With river navigation such a feature of colonial life at the time, the central span was extended to 24 feet to allow boats to pass underneath. The construction of the bridge was widely reported as quite rough, and Henry Trigg had claims against the contractor for the way many of the piles were driven, but the bridge was still a welcome improvement for the settlers who no longer had to use the slow and expensive ferry crossing.
It is worth just noting the achievements of Solomon Cook – he seems to be one of those people who could turn his hand to any technical matter, and had a hand in running mills as well as building and maintaining bridges over a period of years. Among other achievements he built steam powered boats which were used on the Swan River in the 1850’s and he established a foundry in Perth on the site later occupied by Boans/Myer.
The 1862 Flood
The Swan and Canning Rivers have a long history of flooding, although river training, dredging and dams have lessened the effect in recent years. Many people will recall the inundation of Guildford and South Perth in 1955, and as recently as 1926 flooding has caused the collapse of bridges at Fremantle and Upper Swan. Prior to this, however, the great flood of 1862 was one of the most widespread and severe floods in the State’s recorded history.
Records of the day reported flooding along the Swan River from Guildford, the Maylands Peninsular, across the Perth and South Perth Foreshores, and into the streets of Fremantle. There was widespread damage to roads and bridges, with major bridges being washed away at Northam and Pinjarra and others severely damaged on the Canning, Helena, Moore and elsewhere.
The “Perth Gazette” records that “for some days the Causeway at the Perth Flats was entirely under water and for a time nothing was visible there but the centre portion of the flanking of the first bridge”. At the peak of the flood, the Causeway had between 7 and 8 feet of water flowing over it. The Canning Bridge was another of the bridges badly damaged by the flood.
Following the damage of the 1862 flood, a second Canning Bridge was built by convict labour in 1867. From descriptions, the position of this bridge must have been very close to the present upstream bridge.
The new bridge had 26 foot and 27 foot 6 inch navigation spans, with the 38 remaining spans being 13 foot 6 inch each – a total length of 572 feet long and 11 foot 2 inch traffic way width.
This bridge was raised by 6 feet to give increased navigational clearance, to 18 feet above normal water level, in 1892. There is a story about a large dredge being caught upstream of the bridge on the Canning River during this period, but I have found it hard to reconcile the story as written. It would seem to me that the dredge may well have been taken upstream through the bridge in 1892 when the superstructure had been removed for the raising, and then the extent of any miscalculation would have become apparent 4 years later when they had completed the upstream Canning River dredging works and were trying to move the dredge back through the Canning Bridge.
There is an interesting quote regarding this bridge from a talk given by Civil Engineer J E G Turnbull in 1911 to the Western Australian Institution of Engineers: “On the old bridge over the Lower Canning ….the roadway was too narrow for vehicles to pass one another. From each end up towards the centre there was a grade of about 1 in 10, so that it was not possible to see from one end to the other. To make matters worse, the approaches curved away in opposite directions at either end. The consequence was that it was quite possible for two drivers to come on to the bridge from opposite ends and not be aware of one another’s proximity until they almost met at the top. I have seen this happen more than once, together with the foregone conclusion, which was that after argument, and language, one driver had to back his horse the whole way down the steep grade and off the bridge – a very awkward and possibly dangerous proceeding.”
Lack of regular maintenance funding, possibly resulting from the relatively low priority of the Perth Fremantle road compared to other transport routes, meant that the bridge deteriorated steadily during the 1890’s and into the start of the 20th century. I have encountered a report that the bridge was also badly damaged by fire early last century, so its replacement was now becoming critical and State government funding was finally provided in 1907/08.
Canning Bridge – 1908
This bridge was sited on an angle south east of the present bridges, and was known as Lower Canning Bridge, on the Perth Fremantle Road. The arch over the navigation opening was flattened considerably, down to 1 in 25, compared to the previous bridge. The width of the new bridge was also adequate to allow the traffic of the day to pass each other safely without the dramas encountered by Engineer Turnbull.
It was 570 feet long, comprising 24/20 foot spans, one 40 foot truss navigation span; and 2 short 5 foot support spans bordering the navigational channel. It was 16 feet wide and much stronger than the bridge that it replaced. Built by contract, it cost £2,023 pounds.
Starting a tradition which continues to the present day, a fishing platform was added under the bridge soon after it was constructed.
Canning Bridge (No.913) – 1938
The construction of the new Canning Bridge was commenced by Main Roads in July 1937. It was a driven pile timber structure 520 feet long consisting of 24/20 ft spans and a central navigation span of 40 feet, with masonry abutments. The vehicular width was 27 feet, with a 5 foot footway provided for pedestrians. The bridge was completed and officially opened on 29th April 1938 by the then Minister for Works (the Hon. H Millington MLA). The cost of the bridge and approaches was £24,830 pounds.
It is worth noting that this bridge was one of a series of major metropolitan bridges which the WA Government of the late 1930’s had directed to have important structural elements constructed from karri timber, to demonstrate its strength and durability – and so the halfcaps were formed from sawn 14”x6” karri, treated with a method known as ‘fluarizing’. ‘Fluarizing’ involves boiling the timber in a mixture of sodium fluoride and arsenic trioxide, producing an envelope of timber which is resistant to rot and termite attack.
After 38 years of service, the bridge deck received a reinforced concrete overlay in 1976.
In 1994/95, the original karri halfcaps had deteriorated to such an extent under the ravages of termite attack that they were replaced with steel. The outside of the timber had been protected by the fluarizing treatment, but termite attack and decay had commenced at bolt holes and similar weak points, and we were left with just a shell of timber holding up the bridge superstructure.
The bridge received a substantial superstructure maintenance and replacement of the reinforced concrete overlay in 1998/99, leaving it in place for many more years of service.
Stephenson Hepburn Plan 1955
An event of great importance to Perth occurred in Liverpool, England in June 1952 when a group of WA authorities including State Director of Works Russell Dumas first spoke to Professor Gordon Stephenson. The WA Town Planning Commissioner D I Davidson had died, and they were looking to recruit both a new town planning commissioner and a senior consultant in order to develop a comprehensive regional plan for Perth to guide its post war development. Stephenson arrived in Perth in January 1953 to perform the consultancy role, followed soon after by the new Town Planning Commissioner Alastair Hepburn. They were to form an outstanding and effective team – the academic and progressive Stephenson, who had already had tremendous success in his planning roles at Toronto and at the Greater City of London, and the wise, calm and cautious public servant Hepburn – backed by an enthusiastic and progressive State Government.
In 1955 Stephenson and Hepburn released their “Plan for the Metropolitan Region, Perth and Fremantle, 1955” which discussed in detail many facets of life in the Perth area and suggested how it might be developed for a metropolitan population likely to reach 1.4 million people by the Year 2000. In regional planning, one of the first essentials is to define and establish lines of communication, and so the Plan proposed an extended freeway system to complement and supplement the public transport system. In his 1992 autobiography, Stephenson reiterated his belief that ‘a rapid transit system is not an answer in itself, contrary to the fashionable belief that freeways are bad and a public transport system is good.’ He seemed to have a clear grasp of the practicalities of developing a total transport system in a city with the existing development, topography and potential of Perth.
A major effect of the Plan was to change the traditional alignment of the metropolitan region from west to east along the Swan River to north and south. As a result the Swan River, which had been the major factor in Perth’s geography and development for over 100 years, became a barrier to further growth. The task for Main Roads would be to provide the major roads agreed from the Plan and to build the bridges for them. The most important road was a freeway running north-south to link the existing major centres of population with the growth areas which would develop north and south of the city. This freeway would be the backbone on which the remodelled Perth was built.
The first part of this spine was the Kwinana Freeway, running from Perth, via a new bridge over the Narrows, along the South Perth foreshore of the Swan River, and linking up with Canning Highway at Canning Bridge.
Canning Bridge (No.912) – 1958 (upstream bridge)
The concentration of traffic on Canning Highway, with allowance for future development meant that Canning Highway needed to be upgraded to a dual carriageway and the Canning Bridge needed to be duplicated. It is interesting to note that the alignment of the new freeway meant that it was desirable to have the new bridge 3 spans shorter than before, to accommodate the new freeway on ramps. Fortunately, the construction of Canning Dam had reduced the flood flows in the Canning River and not only made the shorter new bridge possible - the existing bridge was also shortened by 3 spans at the eastern end, resulting in matching 22 span 2 lane timber bridges.
Such was the traffic growth immediately following this period that both of the Canning Bridges were widened by an extra lane each in 1965. The bridge had a reinforced concrete overlay constructed in 1984 to prolong the life of the decking and timber superstructure.
Heritage Importance
The pair of bridges that is Canning Bridge was recognised in 2006 by inclusion onto the Heritage Council of Western Australia Register of Heritage Places. This recognises both the history of the site and the representative nature of the current bridge construction.
Author: Lloyd Margetts, Senior Bridge Engineer, Main Roads WA
