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 the State’s 20 urban and rural water corporations.

Rainfall

For the first time in a number of years Victoria experienced average or above average July rainfall. Above average falls were recorded in Central district, the Latrobe Valley and east Gippsland. Geelong and surrounding region recorded falls very much above average. The rest of the State received average rainfall. Mean daily maximum temperatures for Victoria were close to average across the State, slightly below in the north and east, slightly above in the south and west. Melbourne received 62.8 mm of rain during the month, which is above the long-term July average of 48.8mm.

Streamflows

Average to above average rainfall during July saw an improvement in stream levels across the State. However, streamflows continued at drought levels in the Mallee, Central and North Central Victoria. Streamflows in Gippsland and the Great Dividing Range experienced flows up to 100% of the long-term average, whilst flows at the end of the month in the State’s southwest were well below the long-term July average.

Storage Levels

For the first month this year, storage volumes increased in all of Victoria’s major storages. Volumes in the major storages increased by 4.9% in July to be at 22.8% of capacity. Melbourne Water's storages increased by 4.8%, to finish the month at 35.8% of capacity, whilst Rural Water Corporation storages increased by 4.9%, to finish the month at 20.5% of capacity. Storages in the Glenelg-Wimmera Basin rose to 8.8% of capacity, Lake Eildon rose to 17.5% of capacity and Rosslynne Reservoir increased slightly to 4.9% of capacity.

At the end of May 2007, water levels were below average and falling for most of the key groundwater management areas in the State.

Urban Water Restrictions

A number of key changes to towns on restrictions took effect during July 2007. Restrictions were increased to Stage 4 for customers supplied from Murray and Goulburn rivers. In contrast, Stage 4 restrictions were lifted or reduced for a number of towns in Gippsland and north-east Victoria. The total number of Victorian towns on restriction as at 31 July was 436, of which 31 towns were on Stage 1, 52 were on Stage 2, 44 were on Stage 3, 18 on Stage 3a and 291 were on Stage 4 restrictions.

Irrigation Allocations

G-MW made its first allocation announcement for the 2007/2008 season on 2 July 2007, its second announcement on 16 July and its third announcement on 1 August. As of 1 August, allocations were zero on all systems. Carry-over water was available on both the Goulburn and the Murray systems. The resource position has improved in the last few weeks. However, there is still a large volume of water required in the major systems to meet all system losses and other fixed requirements prior to allocating water. G-MW will provide the next allocation announcement and updated outlook on 15 August 2007. The 1 August outlook indicates that a zero allocation will continue for all systems except the Goulburn, where it is possible that a small allocation will be available on the Goulburn system.

In the south-east of the State, Blue Rock Lake increased to 65.1% of capacity. The irrigation share of Blue Rock stands at only 1,356ML, or 11% of regulated allocation. Southern Rural Water licence holders downstream were permitted to take up to their licence volume, but availability was limited by low unregulated river flows. Lake Glenmaggie, which supplies the Thomson-Macalister Irrigation District (MID), continued to spill. The 2007/08 irrigation season will open on 15 August 2007 with an opening allocation of 100%.

In the south-west of the State, SRW’s share of the Werribee Basin storages rose slightly to 9.2% of capacity following minimal inflows during July. SRW made an opening seasonal allocation for 2007/08 on 1 July of 0% water right and 100% domestic and stock. This is a temporary allocation for the period July to 1 September 2007. Levels in the Deutgam Groundwater Management Area have continued to decline. To protect the resource from seawater intrusion, SRW qualified and suspended rights from 27 June 2007. Storage volumes in Rosslynne Reservoir remain low at 4.9% of capacity. With inflows well below average, SRW diverters face another season of low allocations.

Restrictions on Diversions

Changes in restrictions on unregulated streams reflected the improvement in streamflows over the past month in north-central and eastern Victoria. At the end of July, diversions from a total of 118 streams and lakes across the State were subject to some form of restriction. This compares to 149 streams at the end of June 2007.

Seasonal Climate Outlook

The Bureau of Meteorology reports no strong swings towards above or below normal rainfall in Victoria over the next three months. The chance of a La Niña occurring is now about 50:50; however, if neutral conditions persist it is likely that even if a La Niña fails to eventuate, conditions are still likely to be wetter than average across eastern Australia.