Water

Promising forecast for Vic irrigation

By Country News

Irrigation outlooks for the next season are looking promising, according to the latest forecast.

Goulburn-Murray Water northern Victorian resource manager Mark Bailey updated the outlook for 2018-19 seasonal determinations last week.

Dr Bailey said the Goulburn and Loddon systems were expected to start the 2018-19 water year with seasonal determinations of about 20 per cent of high-reliability water shares or better.

The Murray system is expected to start with a seasonal determination of at least 40 per cent HRWS.

‘‘The Campaspe system is expected to receive 100 per cent HRWS in the first 2018-19 announcement on July 2,’’ he said.

‘‘Early season announcements in the Broken and Bullarook systems will be influenced by the volume carried-over and catchment conditions.

‘‘Carryover will be deliverable in systems under all scenarios.

‘‘All of the northern Victorian systems are expected to have seasonal determinations of 100 per cent HRWS by mid-October under average inflow conditions.’’

Dr Bailey said the updated 2018-19 outlooks had not changed significantly since the first outlook published in February.

‘‘Conditions have been warm and dry across northern Victoria through autumn and storage levels are yet to increase.

‘‘Recent rain has started to wet the catchments but more rain is needed before flows into the major storages cause storage levels to rise.

‘‘Based on the historical flow record, it is estimated that the probability of spill during 2018-19 in the Goulburn system could be about 30 per cent and about 75 per cent in the Murray system.

‘‘The probability of spill in the Campaspe system is expected to be about 50 per cent at the start of 2018-19.

‘‘Customers may wish to factor this into their plans for the remaining weeks of 2017-18.’’

The resource manager uses historical flow records to assess the seasonal determinations for a range of inflows to the major storages.