The
bridge starts to go under when the river water is 2.6 m deep. The gauges on the
bridge only measure flow above the roadway. This is unlikely during the comfortable travel season of May to Sept when there may be a
pool or a bone dry riverbed. Since 1974 all floods have been in Dec to March. In March 2011 the
bridge went nearly 4 m under during a 6.5 m flood. Access is severely disrupted in a big Wet as the roads turn into quagmires.