Low flows into Eildon see Goulburn risk of spill revised down

In the Murray, Goulburn and Campaspe systems, irrigation water entitlement holders are able to carry over a volume of up to 100 per cent of their high and low reliablity water shares.

When seasonal determinations are greater than zero per cent, entitlement holders may have more than their total HRWS and LRWS volume - if this happens water is quarantined in a spillable account, and may be lost if the dams overflow.

When a low risk of spill is declared, the water in the accounts is returned to allocation.

Resource manager Mark Bailey said the risk of spill in the Murray and Campaspe systems, during 2020-21, remained above the 10 per cent threshold, required to declare a low risk of spill.

"The risk of spill in the Goulburn system during 2020/21 has fallen below 10pc, after flows into Lake Eildon declined during July," Dr Bailey said

"The below-average rainfall during July caused flows to all major storages to decline.

"The risk of spill in the Murray system from Victoria's share of the volume in Lake Hume reduced to about 40pc and the risk of spill from Lake Eppalock in the Campaspe system reduced to about 25pc."

Dr Bailey said the risk of spill assessment did not describe the chances of flooding in the Murray, Goulburn or Campaspe systems this season.

"The risk of spill is a water accounting assessment. It does not refer to flood risks downstream of the storages," Dr Bailey said.

Allocation trade from NSW to Victoria is limited to the lesser of a net annual volume of 200 gigalitres, or a volume that keeps the risk of spill in Victoria's share of the both Hume and Dartmouth reservoirs below 50pc.

The current risk of spill in the Murray system allows 200 GL of net trade from New South Wales to Victoria.

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