Hampden Bridge – History
Hampden Bridge was completed in 1895. Prior to the construction of the Hampden Bridge, a bridge built by a group of local businessmen and property owners had been located over the river, and was known as the Company Bridge.
The bridge was a much needed resource for the growing town. However, in order to recoup the cost of building the bridge, the Company placed a toll on the bridge, and this caused a considerable amount of local conflict. In 1884 the colonial government purchased the bridge. However, it began to decay and by the early 1890s it was in need of replacement.
It was decided to try to build a bridge with a larger span, to avoid many of the problems that occurred with the shorter 70 foot span of the Company Bridge during times of flood. Initially tenders were called for an iron bridge, but when these were deemed too expensive, a timber bridge using Allan’s design was decided upon (Allan, 1895). The Hampden Bridge was one of the earliest bridges built using the innovative design of Percy Allan, and was the first overhead brace truss constructed. It was completed and opened in 1895.
Given its location at an important crossing, the bridge has had considerable use during its years of service. As a result, it has also undergone many periods of maintenance and the replacement of many components of the bridge. Ease of replacement of damaged or decayed timbers was a key feature of Allan’s design. Another feature contributing to the extensive life of the bridge is Allan’s factor safety of seven, which at the time was ‘somewhat in excess of actual requirements’ (Allan, n.d) but meant that in recent times the bridge was able to handle the heavier loads of modern traffic.
A recurring issue with the Hampden Bridge has been the issue of maintenance. The cost of maintaining timber bridges is generally high (North, 2012), as maintenance often does not last for as long as anticipated, and the initial cost is usually more than first estimated. The inconvenience caused to local traffic during times when the bridge was out of regular service placed an increased burden on the Wagga community in a way that is difficult to measure.
In 1992, the City Engineer in a report to council noted that since 1970, there had been three ‘major refurbishments’ of the bridge. Each refurbishment was intended to fix the larger issues with the bridge, with the hope that only minimal maintenance would be required thereafter. In practice, each major refurbishment had a life cycle of approximately eight years.
In 1996, a stabilisation report prepared on the condition of the bridge by engineers Hughes Trueman
Ludlow noted that following a period of intense maintenance carried out by the RTA, the bridge had been in good condition, but at the time the report was prepared the bridge was in danger of decay if maintenance was not regularly carried out.
By August 2006, the bridge was in a poor condition, and it was closed to the public indefinitely as it was discovered that one of the decks had dropped 50 centimetres. Stabilisation action occurred at the time, but no rehabilitation strategy was implemented, and the bridge continued to decay. Estimates at the time suggested the bridge may cost in excess of a million dollars to rehabilitate. $300,000 was committed to stabilisation works in 2007.
By August 2008, there was genuine concern that the bridge could fail, and a large steel truss was positioned to help lift up the failed deck.
In March 2012 Wagga Wagga City Council voted to demolish the bridge.
This information was taken from the document:
‘Statement of Heritage Impact - Hampden Bridge, Murrumbidgee River, Wagga Wagga, May 2013, NGH Heritage