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

The first two days of March showed a continuation of February’s weather pattern, which brought heavy rainfalls in east and west Gippsland. Two weeks of dry conditions followed, but March 16 marked the start of significant rainfalls across the State. Overall, March rainfall totals were close to the 1961-1990 average across the State. Exceptions were a small region covering the Otway Ranges and another east of Orbost, where rainfall was below average, and Victoria’s alpine areas which enjoyed above average falls.

Across Victoria, maximum temperatures were above average, with some sites recording their highest March mean daily temperatures for at least 20 years.

Streamflows

Given the prolonged dry conditions, catchments across the State are very dry, and despite reasonable rainfalls throughout March, most streamflows remained well below the long-term monthly average. At the end of March, around 60% of the State had flows that were less than 10% of the monthly average for March and over 40% of reported streamflow stations around the State recorded zero flows.

Storage Levels

Volumes in the major storages in Victoria reduced by 1.5% in March. Melbourne Water's storages reduced by 2.1%, to finish the month at 32.0% of capacity (19.1% lower than at the same time last year). Rural Water Authority storages decreased by 1.4%, to finish the month at 10.5% of capacity (23.9% lower than at the same time last year). Storages in the Glenelg-Wimmera Basin were at 3.8% of capacity compared with 6.6% at the same time last year. At the end of the month, Lake Eildon was at 7.5% of capacity compared with 24.9% at the same time last year, and Rosslynne Reservoir was at 4.4% of capacity compared with 8.5% at the same time last year.

Urban Water Restrictions

A number of new or increased urban restrictions took effect during March 2007. Key changes included the imposition of Stage 3 restrictions for Amphitheatre, Blackwood, Barry’s Reef, Bonnie Doon and Beechworth. Stage 4 restrictions were imposed for Longwood, Glenrowan, Myrtleford and all towns serviced by the Mitchell River, Lance Creek and Tarwin River systems. The total number of towns subject to water restrictions as at 31 March 2007 was 456 (compared with 153 at the same time in 2006). Ninety-three towns were on Stage 1, 35 on Stage 2, 73 on Stage 3, and 255 on Stage 4 restrictions

Irrigation Allocations

Water allocations for the 2006/2007 season were updated by Goulburn-Murray Water on March 1 and 15 2007. The scheduled end of the Goulburn irrigation season was extended to 30 April 2007, and the irrigation allocation was increased 2% to 27%. The allocation on the Broken was increased from 72% to 74%. The irrigation season for the Torrumbarry irrigation area was extended to 30 April 2007. The season closing date for the Murray Valley irrigation area remains at 30 April 2007. There is still no allocation for irrigation entitlements in the Campaspe and Loddon systems. In the Murray system, the allocation remains at 95% of Water Right and Licensed Volume. In the Bullarook System, customers supplied from Newlyn Reservoir have an allocation of 36% and the customers supplied from Hepburns Lagoon still have an allocation of 0%.

In the south-west of the State, allocations remain at 10% for the Bacchus Marsh and Werribee Irrigation Districts. Levels in the Deutgam Groundwater Management Area are low, and in order to protect the resource from seawater intrusion, allocations for the 2006/2007 season are at 25% of licensed volume. Rosslynne Reservoir is at 4.4% of capacity and the allocation for Southern Rural Water diverters is 5%.

Restrictions on Diversions

In the south-east of the State, on the Latrobe system Blue Rock Lake is at 54.8% of capacity. SRW licence holders downstream are permitted to take up to their licence volume, but availability is likely to be limited by low unregulated river flows (which normally contribute some 70% of entitlements). Lake Glenmaggie, which supplies the Thomson-Macalister Irrigation District, decreased to 9% of capacity during March. The allocation for irrigators in the Northern, Eastern and Tinamba/Riverslea areas remains at 48%, and the seasonal allocation for irrigators in the Nambrok-Denison area remains at 50%.

Seasonal Climate Outlook

The Seasonal Outlook released by the Bureau of Meteorology on 26 March 2007, for the April to June period, continues to show near neutral odds across the State of exceeding the median rainfall. Likewise, the temperature outlook for April to June shows that the chances of exceeding the median maximum temperature are close to 50% across the State. The 2006/07 El Niño event has ended and the chance of a La Nina event developing in 2007 is thought to be higher than the long-term average.

Overall, there is “cautious optimism” that there will be a general easing of dry conditions in drought-affected areas over the next one to two seasons. However, this is the time of year when predictability of the climate system is at its lowest.