Guildford Pipe Bridge
The Swan River is spanned by 23 bridges – 13 road bridges, 6 rail bridges, 3 foot bridges and one water bridge. The water bridge, which has an uninterrupted span right across the river on one great steel arch, carries a single 750mm steel water main.
During a recent clean out day, a box of files and photographs of the design, fabrication, testing and erection of this bridge in 1964 were uncovered by the Water Corporation.
This bridge is the latest link across the Swan River between the Midland/Guildford and the Perth Water Supply Systems, which allows for water from Mundaring Weir (of Kalgoorlie Pipeline fame) to also supply the City. The first of these links was a 200mm main laid in 1914 across the old original 1881 Fremantle-Guildford railway bridge, (though by this time it has been converted to a road bridge with the construction of a replacement dual narrow gauge rail bridge in 1906). This was amplified in 1919 to include a 305mm main as well. In 1949 both of these were lifted and a new 305mm main laid.
By the 1960’s this pipe was insufficient to cater for the rapidly growing suburbs around Bassendean, Morley and Dianella so it was decided to provide a new 750mm main linking the Guildford system to Yokine Reservoir. As the original bridge was virtually derelict and WAGR needed the land to build their new standard gauge bridges, it was decided to make our own. A tied arch arrangement was chosen as it provided for a clear span, could be prefabricated off site and did not require pile driven piers in the middle of the river.
The bridge was entirely designed by the Metropolitan Water Supply, Sewerage and Drainage Department and prefabricated in the old Loftus St welding shop (on the site of the current Water Centre). The pieces were then taken to the Guildford bank of the river where they were assembled. Then, in the culmination of months of planning, it was swung out over the river and mounted in place in a single day. In information provided for his biography, Jim Paton mentioned that he was the construction engineer for this work.
It spans 64m and is 6m above the water with a maximum height at the top of the arch of 12m.
In 1984 a photograph was sent, anonymously, to the Water Corporation's Guildford Depot showing a base jumper and assistant on the very top of the arch, with the jumper’s drogue deployed as he is in the act of jumping off! It was not known the state of the jumper after the attempt as it was unlikely his chute would even be able to deploy before he hit the water.
The original load testing model still exists and was recently restored for eventual display. The 1/36 scale model is a perfect replica of the real thing and an outstanding example of the craftsmanship our own mechanical tradesmen were capable of.
References:
Author - Perry Beor
13 June 2022
