Reducing the perversion of diversion: Applying world‐standard fish screening practices to the Murray–Darling Basin

Abstract

Summary The impact of water diversion on fish populations is a global issue. Many countries have invested substantial funding into research and implementation strategies to ensure fish are protected at diversions that take water out of rivers for agriculture and other human uses. The most common management action is the installation of fish screens, and a wide range of designs are presently available that suit a large range of diversions. The Murray–Darling Basin is the largest catchment in Australia and has been substantially developed over the past 100 years to store and divert water for that protect fish from escaping into the irrigation systems. Recent studies have determined that water diversions have substantial impacts on native fish populations, but there are presently no coordinated efforts for mitigation strategies. The purpose of this review is to highlight aspects of successful screening programmes worldwide and identify those that could be directly applied to the Murray–Darling Basin. The development of similar programmes in the United States, New Zealand and the United Kingdom has identified that sufficient information and technology exists to inform the development of fish screening programmes. There is no need to commence implementation from first principles, and substantial progress can be achieved by applying successful aspects of other programmes. By identifying existing designs, defining ecological targets, developing generalised guidelines appropriate for local conditions and engaging the community, a co‐ordinated and successful fish screening programme could be directly applied to the Murray–Darling Basin. This would have substantial benefits for the long‐term sustainability of native fish without compromising water supply requirements.