The theory put up by the Department of Sunstainability and the Environment is that half of the 900GL total loss shown from its computer program will increase the efficiency from 70 per cent to 85 per cent.

In 2005-06, two model computer runs were carried out by the DSE - the first utilised the Murray Darling basin cap model in December 2006.

This cap model was independently audited and accepted by the commission.

The second run by the DSE was for the Foodbowl Modernisation Project, but the results do not match the results used in the cap model.

The cap model produced by the Murray Darling basin cap shows total savings of 156GL per year, compared to the Foodbowl modernisation project proposal of 450GL per year.

The results from the Foodbowl project model run are so optimistic there is no way this could be representative of the behaviour of the Goulburn Murray District irrigation system.

It appears that the Labor government will use the DSE to muddy the waters to such an extent that the 475GL total savings proposed by the Government will include 345GL stolen from irrigator allocations.

Goulburn Murray Water has reduced the efficiency of the gravity irrigation system from 80 per cent to the low 70s in the Goulburn component and high 60s in the Murray component.

The losses up to 80 per cent efficiency can be overcome with targeted annual maintenance program.

Only savings above 80 per cent efficiency can be distributed in accordance with the Government’s directive.

Rerunning the Murray Darling basin cap model 2006 to include the above condition reduces the savings to 129GL.

For the period 1985-2007, the annual reports show savings of 130GL, which proves the Foodbowl modernisation project proposal, showing 450GL savings in the Goulburn Murray district is wrong.

The results shown to date are based on historical information, but irrigators need information for the next 20 years on which to base decisions.

The savings shown by using the reduced diversion for this period are 105GL.

The end result is that Melbourne Water will receive 12GL, environment 64GL and the irrigators 29GL.

BRUCE M. BASSED,

Colbinabbin.