The Monthly Water Report provides a summary of the status of Victoria's water resources and water supplies at the end of the reporting month. It is based on validated water resource information provided by Victoria's 19 Urban and Rural Water Corporations and the Bureau of Meteorology. Each month's report is published online the following month. For detailed, specific and up-to-date information, please contact the relevant Water Corporation or the Bureau of Meteorology. Links to these organisations are located within the Monthly Water Report.
For a weekly snapshot you can now download the Department's Fortnightly Water Report on the Water Register website.
April was drier than average across most of Victoria, particularly in parts of East Gippsland where it was the lowest on record. For the State as a whole this was the driest April since 1997. Total monthly rainfall was 68.5% below the long-term mean of 51 mm.
At the end of April, one site in the South West of the State experienced high streamflows above 100% of the long-term average for the month (Glenelg River at Sandford at 108% of the long-term average). Moderate streamflows were recorded in the North East and southern parts of the state (Merri River at Woodford, Yarra River at Millgrove and Snowy River at Granite Flat). These sites recorded 96%, 80%, 60% of the April long term streamflow average respectively.
At the end of the month, flows at 17 of the 28 representative stations recorded less than 10% of the long-term average for April. Eleven sites across the State were dry at the end of April. A further six sites across the state (Suggan Buggan River at Suggan Buggan, Mitchell River at Glenaladale, Tarra River at Yarram, Moorabool River at Batesford, Woady Yalloak River at Cressy and Hollands Creek at Kelfeera) recorded low streamflows under 10% of the April long-term average.
The total volume of water held in Victoria's major storages decreased by 4.2% during April, ending the month at 56% capacity. Decreases were recorded in all 16 monitored systems, with the Latrobe, Thomson/Macalister and Broken systems recording the largest percentage falls of 15.5%, 13.9% and 9.9% respectively. There was a 3.6% reduction in the storage volumes in the Victorian Murray system.
Victoria’s regional storage levels decreased by 4.5% to 55.4% of capacity during April. Melbourne’s storage levels decreased by 2.4% to 59.7% of capacity over the same period. Victoria’s major storages were 10.9% lower than at the same time last year.
Groundwater is reported quarterly. The next update will be in June 2018.
Urban water restrictions
On 15 March 2018, South Gippsland Water implemented Stage 2 restrictions for Korumburra. Since this time, storages have continued to decline and South Gippsland Water has announced that Stage 3 restrictions will be implemented from midnight 3 May 2018. All other towns are subject to Permanent Water Savings Rules.
This time last year, South Gippsland Water placed Korumburra on Stage 1 restrictions. This was due to dry conditions and falling dam levels. All other Victorian towns were subject to Permanent Water Saving Rules.
Seasonal determinations in all GMW systems remained at 100% High Reliability Water Share (HRWS) from the previous monthly report. There was no change to Low Reliability Water Share (LRWS) in the GMW system from the previous monthly report. The next seasonal determination will be made on 2 July.
The HRWS seasonal determination for the Werribee/ Bacchus Marsh Irrigation Districts stands at 45%, and at 100% HRWS for the Macalister Irrigation District. A 20% LRWS was announced for the Macalister Irrigation District on 24 April 2018.
Restrictions on diversions
At the end of April, there were 87 unregulated streams subject to diversion restrictions across Victoria, 6 less than reported at the end of March. This time last year, there were 66 waterways subject to restrictions.
Seasonal climate outlook
The Bureau of Meteorology (BoM) released its latest ENSO Wrap-Up on 24 April 2018. The El Niño–Southern Oscillation (ENSO) Outlook remains neutral —neither El Niño nor La Niña. All climate models indicate the tropical Pacific Ocean will continue to warm slowly.
ENSO neutral conditions are expected for the remainder of the southern autumn and winter. A neutral ENSO pattern does not necessarily signify average rainfall. Rather, a reduced chance of prolonged very wet or dry conditions, and that other climate drivers may have greater influence over the coming months.
BoM released its latest May to July 2018 climate outlook on 26 April 2018. The outlook indicates below average rainfall is likely for parts of southwest Australia and western Victoria.
Water for the environment
Environmental use is reported quarterly, with the next update due June 2018.