The Development of Wave Wake Criteria for the Noosa and Brisbane Rivers in South East Queensland
MacFarlane, GJ and Cox, G, The Development of Wave Wake Criteria for the Noosa and Brisbane Rivers in South East Queensland, Coastal Environment 5, 26 -28 April 2004, Alicante Spain, pp. 55-72. ISBN 1-85312-710-8 (2004) [Refereed Conference Paper]
Several rivers in Queensland, Australia, are experiencing bank erosion problems. Public
concern compelled the relevant authorities to commission a series of inter-related studies to
determine the extent of the erosion, its probable causes and a means of quantifying the erosion
potential of vessel wash.
Sections of the Noosa River are in pristine condition, suffering little or no anthropogenic
impact. However, one reach of the river is used by recreational and small commercial vessels
as a transit route between two large lakes and is often traversed at high speed. The Brisbane
River is also used for recreational boating, but the river has undergone significant change
since European settlement almost 200 years ago.
The Australian Maritime College (AMC) conducted field tests to measure the wave wakes of
a variety of craft that frequent these rivers. The wakes were analysed for certain maximum
values such as wave height, wave period and wave energy, as well as total wake trace energy.
Previous experiments attempting to correlate erosion thresholds against wake parameters were
re-analysed and applied to the Noosa and Brisbane Rivers. Vessel operating criteria were
developed for each river in terms of the energy of the maximum wave, maximum permitted
waterline length (which can characterise wave period) and vessel speed. It is proposed that
multiple criteria provides a better indicator of erosion potential than traditional single
indicators such as wave height.