Railways and Tramways of Australia

Two railway bridges have crossed the Hawkesbury River on the Central Coast and Newcastle line, north of Sydney. The original bridge was closed and replaced by the current bridge during the 1940s. It is located around 59 km by rail from Sydney.

 

The First Hawkesbury River Railway Bridge

The first railway bridge across the Hawkesbury River was opened on 1 May 1889. With the completion of this bridge it became possible to travel by train between Brisbane, Sydney, Melbourne and Adelaide. It was the longest bridge in Australia until the opening of the Sydney Harbour Bridge in 1932.

 

Prior to the opening of the bridge, railways extended in 1887 north from Sydney to the current Hawkesbury River station, and south from Newcastle to Gosford. A paddle steamer, the General Gordon, transported passengers between the railheads. In January 1888 the line from Newcastle was extended to Mullet Creek, a tributary of the Hawkesbury River, making a shorter journey for the General Gordon.

 

The first Hawkesbury River railway bridge was designed and built by the Union Bridge Company of New York. It consisted of seven spans and six piers, and had a total length of 2900 feet (884 metres). Each of the spans was assembled on a pontoon and then towed into place. A major challenge was that the rock bed of the Hawkesbury River in the vicinity of the bridge was around 90 metres below the level of the water, and most of the depth was silt and sand. At the time it was impossible to build foundations that deep, so the foundations were laid on coarse sand. Iron tubes called caissons were sunk, the silt was dredged out from inside, and then the tubes were filled with concrete. Eventually the iron rusted, but the concrete remained. When completed, the foundations were the deepest of any bridge in the world.

 

Bridge components were fabricated in Scotland and the United States. A workshop and depot were established on Dangar Island, about one mile downstream from the site of the bridge, and this is where the bridge spans were assembled by contractors. Stone for the piers was obtained from nearby Mullet Creek and from Mt Gibraltar at Bowral.

 

Testing of the bridge took place on 24 April 1889, less than three years after the contract for the bridge’s construction was signed. Two trains with goods wagons, one running in each direction, ran slowly onto the bridge and then stopped while measurements were taken. The trains then moved and further measurements were taken. The total weight of the trains was 909 tons (924 tonnes). Further measurements were made using four locomotives running at 35 miles per hour (56 km/h).

 

To mark the opening of the bridge a grand banquet was held on a barge moored at Dangar Island. Trains bringing guests arrived from Sydney and Newcastle. Guests were given a tour of the bridge before being ferried to the banquet. Among the official guests were Henry Parkes, the Premier of New South Wales, and Lord Carrington, the Governor of New South Wales. Parkes proposed a toast to a united Australia.

 

Concerns were raised less than 12 months after the opening of the bridge. Divers inspected the caissons and found that some were in an unsatisfactory condition. Some of the concrete had been washed away, and testing revealed that much of the remaining concrete was of poor quality. The Union Bridge Company made repairs, but it was not possible to assess the quality of the work at further depths below the water.

 

Increasing locomotive and train weights put greater strain on the bridge and considerable strengthening work was undertaken in the 1920s. A serious crack was noticed in No. 4 pier on 13 June 1937. It was monitored over subsequent months and further cracks developed. One of the two railway tracks on the bridge was closed and trains were required to slow to 10 miles per hour (16 km/h) when crossing the bridge, which was later further reduced to 5 miles per hour (8 km/h). Inspections including diamond drilling and the building of an accessible shaft into the caisson revealed large gaps in the concrete, which were filled with mud. It was found that the original work on the bridge was of such poor quality that the construction of a new bridge was required.

 

The Second Hawkesbury River Railway Bridge

A number of options for the design of the new bridge were considered, with the design selected being similar to the old bridge, and built around 60 metres upstream from it. The new bridge was designed and fabricated by the Department of Railways, with most of the steel fabrication work undertaken a Chullora Workshops in Sydney. It has eight spans, but not all are of equal length, enabling the piers to be located in favourable positions. The deepest pier is 183 ft 7 in (56 metres), which is more than 21 feet (6 metres) deeper than the 1889 bridge’s deepest pier, and the total length of the bridge is 2764 feet (842 metres), making it shorter than the old bridge.

 

The outbreak of the Second World War in 1939 placed greater importance on the need for a new bridge as it was of high strategic importance for the transport of manpower and equipment. Construction work on the bridge went on throughout the war. Workshops and slipways were established on the end of Long Island, at the southern end of the bridge. Steel was delivered by train from Chullora. Like the building of the first bridge, caissons were sunk. More than 49,000 cubic yards (37,463 cubic metres) of concrete were used in the foundations, piers, abutments and southern spans. Following the floating of the spans into place, track was laid across the bridge.

 

By June 1946 the new bridge was ready for testing. At this time C38 Class express passenger locomotives were new, with the first having commenced service in 1943. Locomotives 3801 to 3805 and 3807 were used to test the bridge, being coupled in two groups of three engines: 3802, 3801, 3804; and 3803, 3807, 3805. Five tests runs were made across the bridge on 24 June. The bridge was opened on 1 July. An official train from Sydney was hauled by C32 Class locomotives 3374 and 3295, with 3295 being detached at Hornsby. On board were the Premier, William McKell, Minister for Transport, Maurice O’Sullivan, Commissioner for Railways, Thomas Hartigan, and other special guests. 3374 was in polished green livery and the official train crossed the old bridge at the regulation speed of 5 miles per hour (8 km/h), becoming the last train to cross it. The last regular passenger train had passed about 20 minutes earlier when No. 48 passenger from Tamworth crossed the bridge hauled by C36 Class locomotive 3674. Work was undertaken immediately to change the track connections from the old bridge to the new bridge. 3374 cut off the northern end of the official train and 3810 was attached to the southern end. Flags and the New South Wales coat of arms were attached to the front of 3810. The train proceeded across the bridge and stopped at the southern end, where a ceremony was held. The Premier cut a ribbon and two bronze plaques were unveiled. Following refreshments the guests again boarded the official train, which was hauled by 3810 back to Sydney. The spans of the old bridge were removed in 1947 and 1948, while the piers remain to this day. Some of the steelwork was re-used in other locations throughout New South Wales, including the viaduct leading to Circular Quay station.

 

Viewing the Hawksbury River Bridge

Regular trains pass over the Hawkesbury River Bridge and this is the best way to view and experience it. Central Coast and Newcastle trains operate across the bridge every 30 minutes in each direction for most of the day. Services are more frequent during peak hours. The pylons of the old bridge can be seen on the right-hand side of the train when travelling north.

The Riverboat Postman is a 3 hours and 15 minutes cruise that departs from Brooklyn Public Wharf, adjacent to Hawkesbury River station, at 10.00 am on weekdays. It operates as a sightseeing cruise, but has also delivered mail to isolated communities along the Hawkesbury since 1910. The Riverboat Postman passes underneath the current Hawkesbury River railway bridge.

 

References

‘First spans over the Hawkesbury’, Australian Railway Historical Society Bulletin, no. 145, December 1949, p. 71.

Phippen, B, Between a rock and a hard place: building the Hawkesbury River bridge, exhibition programme, Train Works, 2012.

Phippen, B, The Hawkesbury River Railway Bridges, Australian Railway Historical Society, Sydney, 2000.

The Riverboat Postman <www.riverboatpostman.com.au>.

Wallace, I, ‘Hawkesbury River to Woy Woy’, In Dunn, I, et. al. Byways of Steam 10, Eveleigh Press, Sydney, 1995, pp. 6–44.