Built in the early part of the 20th century on a foundation of timber piles, the Toombul rail bridge at Kedron Brook is a vital link for all passenger and freight trains entering Brisbane from a northerly direction. It is a major artery traversing the Kedron Brook waterway across Shultz canal which is subject to flash flooding during significant rain events.
An inspection of the foundations in early 2012 after the wet season revealed that a number of the old timber piles under one of the centre caissons had rotted away and were no longer in contact with the concrete foundation. Due to the high cost of replacing the bridge, a decision was made by QR for an urgent repair of the foundation.
Due to the critical nature of the bridge, the design brief required the foundations to be repaired without closing the bridge. The Kedron Brook waterway is also an environmentally sensitive creek that flows out into the Brisbane River and Moreton Bay. As such, strict environmental controls were required to maintain the quality of the water in the creek during construction.