Umbrella Environmental Assets: establishing environmental water requirements in the Murray-Darling Basin Matt O’Brien Murray-Darling Basin Authority, Australia Ross Thompson University of Canberra, Australia
Outline Context Umbrella Environmental Assets Murray-Darling Basin and Basin Plan Environmental water requirements at large spatial scales Umbrella Environmental Assets Opportunities to improve approach
It supports over 3 million people Generates about $19 billion per year in agricultural produce Important recreational and cultural areas including more than 40 Aboriginal Nations
Evidence of environmental decline – 2008 Sustainable Rivers Audit
Basin Plan
30,000 wetlands 77,000 km watercourses 95 threatened sp. 16 Ramsar wetlands
Umbrella Environmental Assets Can’t assess whole Basin – lack of data/knowledge/research Hydrological connectivity – watering one environmental asset will water many UMBRELLA ENVIRONMENTAL ASSETS (UEAs)
What is an UEA? Information-rich areas with high environmental values used to represent the water requirements of a broader river reach or valley
Umbrella Environmental Asset approach SPATIAL PRIORITISATION (VALLEY SCALE) SELECTION OF UEAs (WITHIN VALLEY) ENVIRONMENTAL OBJECTIVES FLOW COMPONENTS REQUIRED TO ACHIEVE ENVIRONMENTAL OBJECTIVES
Spatial prioritisation Impacted by flow regulation Contribution to water resource Environmental water requirement assessments already available
Hydrologic alteration PROTECT Increasing flow modification
Selecting UEAs High ecological value Representative water requirements spatially Significant flow alteration Availability of data
UEAs in Murray-Darling Basin Gwydir wetlands Hattah Lakes Macquarie Marshes Coorong, Lower Lakes and Murray Mouth Barmah-Millewa Forest
Defining UEA water requirements UEA environmental objectives Assess EWRs focussing on flow regime components required to support environmental values
Reinstate ecologically significant components of the flow regime
Opportunities EWR knowledge is continually improving UEA representativeness
Take-home messages Knowledge will always be uneven and incomplete UEAs provide a way to deal with imperfect knowledge The application of a standard approach is a significant step forward in large river basin management
Acknowledgements Murray-Darling Basin Authority Jody Swirepik, Ian Neave, Gavin Pryde Murray-Darling Freshwater Research Centre Ian Burns University of Canberra Fiona Dyer