Rainfall

Consistent rain across north and central Victoria during October resulted in above or very much above average rainfall for most of the State.

Rainfall in the Wimmera was below average for most of the month, particularly along the State border. However, rainfall over the last few days of October brought the totals closer to the long-term October average for most of western Victoria. Rainfall in the Gippsland region improved in October in comparison to recent months, however, some areas remain below average.

Stream flows

Rainfall was intermittent throughout October, and the trend of streamflow improvement seen in previous months continued this month.

Of the 28 representative streamflow gauging stations, two stations located in the Alpine region recorded flows above the long-term October average at the end of the month. A further 23 stations recorded flows between 10 and 79% of the long-term October average.

Storages

The total volume in Victoria’s major storages was 69.8% of total capacity at the end of the October. The volume in the state’s major regional water storages increased by 5.1% to 73.3% of capacity, and Melbourne's storages increased by 2.6% to 49.5%.

Restrictions on Urban Water Supplies

Good winter-spring inflows to storages across Victoria resulted in many changes to urban water restrictions during October. Over the month, 79 towns had restrictions removed and a further 102 towns had restrictions reduced. These towns were mainly in the Geelong, Bendigo and Grampians regions. Restrictions were introduced for 3 towns in the Otways during October.

At the end of the month, 161 Victorian towns were on restrictions, which is less than half the number of towns on restrictions at the same time last year.

Irrigation Allocations

G-MW increased allocations for high-reliability water shares (HRWS) for the Murray, Goulburn and Loddon systems during October. At the end of the month, allocations were Murray (100%), Goulburn (80%), and Loddon (80%). Allocations for HRWS on other northern systems remained at 100%, with a 100% allocation for low-reliability water shares (LRWS) on the Bullarook system. The allocation for the Coliban rural system remained at 70% throughout October.

GWMWater increased the allocation on the Wimmera Mallee supply system to 74% in October, however, the irrigation channel run has been deferred this year (in consultation with irrigators).

In southern Victoria, Southern Rural Water increased the allocation for the Werribee and Bacchus Marsh irrigation districts to 70% for HRWS.

The allocation for HRWS in the Macalister Irrigation District will remain at 90% until SRW reviews its decision on 15 December 2010. Future increases depend on rainfall and inflows to Lake Glenmaggie over the coming months.

Restrictions on Unregulated Streams

At the end of October, diversions from a total of 12 unregulated streams and lakes across the state were subject to restrictions. This is significantly less than the same time last year when 117 streams were on restriction.

Seasonal Climate Outlook

The Bureau of Meteorology’s latest rainfall outlook for south-eastern Australia favours wetter than average conditions for November to January.

The Bureau reports that a moderate to strong La Niña event remains in the Pacific Ocean, and that a negative Indian Ocean Dipole event also continues. The combination of these events suggests above average rainfall in south-eastern Australia is likely.