The Monthly Water Report provides a statewide monthly summary of the status of water resources and water supplies. Each month's report is published online towards the end of the following month. It is based on data provided by Victoria's 19 urban and rural water corporations.

Rainfall

Victoria experienced a very dry and hot January with total monthly rainfall very much below the long-term normal across most of the state.

Thirty-six rainfall recording sites across Victoria experienced their lowest January rainfall on record (of these sites, 15 recorded no rainfall at all). A further 41 sites recorded their lowest January rainfall for 20 years.

Streamflows

At the end of the month, streamflows across Victoria continued to decline due to very low rainfall and exceptionally warm conditions.

Of the 28 representative gauging stations, no flow conditions were recorded at 11 stations at the end of the month. A further 9 stations exhibited flows less than 10% of the long-term average for January.

The highest flow of 54% of the long-term January average was recorded on the Yarra River at Millgrove.

Storage Volumes

Extremely low rainfall and warm conditions throughout January have increased the rate of storage level decline across most of Victoria.

At the end of January, the total volume in the state’s major storages was 17.4% of capacity. This is a decrease of 3% over the month. Melbourne’s storages decreased by 1.9% during the month to finish at 33.0% of capacity

Regional water storages decreased by 3.1% to finish the month at 15.4% of capacity.

Restrictions on Urban Water Supplies

Coliban Water eased restrictions for Bendigo and surrounding towns to Stage 3 from 1 January 2009. Central Highlands Water increased restrictions for Beaufort and Raglan to Stage 4 from 2 January 2009. Goulburn Valley Water reduced restrictions for Kilmore, Wandong and Heathcote Junction to Stage 2 from 9 January 2009.

The total number of Victorian towns on restriction as at 31 January 2009 was 334, of which 68 towns were on Stage 1, 47 were on Stage 2, 39 were on Stage 3, 19 on Stage 3a, 67 on Stage 4 with general exemptions, and 94 on Stage 4.

Approximately 175 towns were not on water restrictions and were subject to Permanent Water Saving Rules.

Irrigation Allocations

During January, G-MW increased allocations by 7% to 35% on the Murray system, and by 6% to 29% on the Goulburn system. Allocations remained at 0% on all other northern systems.

The allocation on both the Coliban Rural System and the Wimmera-Mallee irrigation supply system remained at zero per cent during January.

In southern Victoria, the seasonal allocation for the Werribee and Bacchus Marsh irrigation districts was increased to 5% of high reliability water share.

The allocation for the Macalister Irrigation District remained at 95% during January. The irrigation share of Blue Rock Lake was 277 ML or 6.7% of regulated allocation at the end of January.

Restrictions on Unregulated Streams

At the end of January, diversions from a total of 169 unregulated streams and lakes across the state were subject to some form of restriction. This is greater than this time last year when 133 streams were on restriction.

Seasonal Climate Outlook

The rainfall outlook for the period February to April 2009 was released by the Bureau of Meteorology on 22 January 2009. The outlook shows shows no strong bias towards either wetter or drier conditions for Victoria. The outlook indicates that the chances of exceeding the median rainfall across Victoria are between 55% and 60% across most of the state, with between 50% and 55% in the far east. This means that the chances of being wetter than normal are about the same as the chances of being drier.

The ENSO Wrap-Up (issued on 14 January 2009) reveals that the central and eastern equatorial Pacific Ocean cooled further during December. Most current model outlooks, and a build-up of warmer sub-surface water in the western equatorial Pacific, suggest that the cooler conditions in the Pacific may not persist beyond summer 2009. The Indian Ocean Dipole is now neutral and is expected to remain neutral through the rest of the southern summer.