Advisory Group: Hume to Yarrawonga Waterway Management

The Commission agreed to establish an Advisory Group in response to the recommendations of the Hume and Dartmouth Dams Operations Review Reference Panel with respect to a comprehensive management plan for the reach of the River Murray between Hume and Yarrawonga.

The definition of this reach of river includes the river proper downstream of Hume Dam to, but not including, the reach of river within Lake Mulwala under normal operating conditions.

Membership of the Advisory Group includes representatives from the community, local government and agencies.

Purpose

The Advisory Group was established as a formal group under the Murray-Darling Basin Agreement to ensure cross-border coordination. The attached Terms of Reference set the guidelines under which the Advisory Group will operate.

The aim of the Advisory Group is to overcome institutional difficulties of the state boundaries and to formulate long term solutions for the management of the defined reach of the River Murray. In achieving this role the group is expected to advise how integrated waterway and floodplain management of this reach of the River Murray might best be undertaken, and to develop a program for implementation of that management plan.

Hume to Yarrawonga Reach of the River Murray

Between Lake Hume and the Yarrawonga Weir Pool the River Murray falls about 30 metres over a river distance of 180 km or a straight line distance of 65 km. The river channel occupies a meander belt several hundred metres wide within a floodplain up to 5 km wide. There is an extensive anabranch system and the floodplain sediments are very variable.

The flow regime of the Murray between Lake Hume and Yarrawonga Weir is heavily modified by the large storages of Lake Hume and Lake Dartmouth and by the Snowy Mountains Scheme. The average annual flow is some 6% higher than under natural conditions. Summer and autumn flows are much higher than under natural conditions, and winter and spring flows are lower. Regulation increases the proportion of total flow passing down the river channel from about 88% to 94%. The other 6% passes over the floodplain during floods.
Other changes to the river and floodplain resulting from European settlement have been:

• extensive clearing of the floodplain for agricultural purposes
  
  
• changes to bank vegetation because of river regulation, stock access and de-snagging
  
  
• quarrying
  
  
• construction of roads, bridges and levee banks
  
  
• use of the river for recreational boating.

Flooding and bank erosion have been of concern for well over a century, and many reports and surveys exist to document the problems and changes. Although this stretch of river is a vital link in the operation of the Murray for water supply, it has proved difficult to develop arrangements for putting in place a comprehensive strategy for managing the reach. This is partly at least because the river is a State border, so laws and institutional arrangements are not the same on both sides.

For many years the Department of Land & Water Conservation of New South Wales has carried out a program of erosion control on both sides of the river, using Murray-Darling Basin Commission funds. This has been valuable in controlling erosion 'hot spots' but is essentially reactive work rather than a pro-active or comprehensive river management program.

For further information about the Hume to Yarrawonga Waterway project, contact the project manager yarrawonga.project%40mdbc.gov.au