Technical Report Number 3
W L Peirson, K Bishop, D Van Senden, P R Horton and C A Adamantidis - School of Civil and Environmental Engineering, University of New South Wales
Environment Australia, April 2002
ISBN 0 6425 4827 7
About this report
The purpose of this report is to present and explain a method of determining appropriate levels of environmental flows to Australian estuaries. Although the geographic extent of an estuary within a catchment or river basin may be very limited:
- estuaries are primary catchment drainage sites to the coastal ocean; and,
- the physical, chemical, sediment, water quality and ecological processes within estuaries are exceedingly complex primarily due to their dynamic nature, complex mixing processes, stochastic influences, strong antecedent effects and the vast number of complex ecological linkages.
This report is structured as follows:
- We begin in Chapter 2 with the investigative background of this project within Environment Australia's ecological programs associated with rivers and a clear statement of the specific objectives of this investigation.
- In Chapter 3, we review the concept of environmental flows and the key features of estuarine systems. The key differences between estuarine and fluvial systems are highlighted.
- Broad overviews of the relevant ecological, physical and water quality processes in Australian estuaries are presented in Chapters 4, 5 and 6.
- Chapter 7 is a brief summary of Appendix 6 which assembles the key relevant water policy initiatives of Australian government authorities and briefly describes some of the major estuarine investigations undertaken within Australia.
- Chapter 8 is a brief summary of Appendix 7 which is a review of Australian and international estuarine environmental flows studies.
- Based on this material, a methodology to determine appropriate environmental flows to estuaries to maintain their key processes and ecology is described in Chapter 9.
- Chapter 10 lists the information required to support such a methodology and ensure that robust conclusions can be reached by the investigative process.
- Chapter 11 briefly describes some of the practical limitations and opportunities afforded by the assessment of environmental flows to estuaries.
- Chapter 12 concludes this investigation with recommendations for future action.