Oral Presentation International Conference on River Connectivity (Fish Passage 2018)

The cone fishway, a new fishway type suitable for the passage of juvenile tropical fish species in Queensland, Australia. (#133)

Tim Marsden , Ivor Stuart , Andrew Berghuis

Throughout Queensland the passage of juvenile migratory fish is critical to the ongoing maintenance of fish populations. These very small (<20mm) fish undertake extensive migrations that are the basis of fisheries productivity in these systems, therefore providing adequate passage at barriers is essential. The cone fishway is a new pool and weir style fishway developed in North Queensland to replace the rock ramp fishway design for the passage of these small fish. The rock ramp fishway has been a very successful design for juvenile fish species in North Queensland. However, in parts of this region, rock supply can be problematic due to a lack of suitable rock quarries and the vast distances required for transportation. This increases the construction cost of the rock ramp fishway design beyond acceptable limits. In addition, the installation of rock ramp fishways requires skilled engineers and operators with previous rock ramp construction experience, which is difficult to procure in remote regions. The concrete cone fishway was designed to mimic some of the best design features of the rock ramp fishway, use readily available materials (concrete) and be easy to install for non-fishway experts. Through an iterative design process, the concrete cone fishway has been refined into a suitable design for the passage of small fish past low to medium height barriers in North Queensland. With results from a number of demonstration fishways highlighting the designs potential to pass the large number of juvenile migrants that occur in these systems. Cone fishways such as the Fitzroy Barrage Cone Fishway are successful passage of up to 3.4 Million fish per year. The implementation of this design has now spread beyond this region with successful cone fishways now operating in Southern Australia and South East Asia.