A summary of the significant water events, major water initiatives and improvements in water information occurring during the reporting period are explained.
As a response to the continued period of low water availability across the Murray–Darling Basin (MDB), special water sharing arrangements between New South Wales, Victoria and South Australia to share the River Murray water resources have been in place since June 2007. The focus of the arrangements in 2009–10 was to provide in order of priority:
Note that 25,000 ML is a proportionate share of the resource available to the States. It is still up to the State and relevant authorities to set the level of allocations for each part of their system.
Because of the late season improvements in volumes of Menindee Lakes and the River Murray, these special arrangements formally ceased in May 2010.
Severe flooding occurred in northwest New South Wales in December 2009 – January 2010 when tropical cyclone Lawrence became slow moving near the Queensland – New South Wales border. Up to 200–300 mm was recorded at official gauges, which caused major overland flooding between Bourke and Brewarrina, and in the lower Namoi Valley. Record major flooding occurred along the lower Culgoa River from heavy local rainfalls of up to 480 mm. On 1–2 January 2010, major flooding was experienced in the town of Coonamble; there was also flooding in the Culgoa, Barwon–Darling, Macintyre, Bogan, Macquarie, Paroo, Warrego, Hastings and Bellingen rivers (Bureau of Meteorology 2010).
Further inundation occurred in March 2010 resulting in major flooding along the Culgoa, Bokhara, Birrie, Narran, Paroo, Warrego and Barwon–Darling rivers. Flow from the Paroo River reached the Darling River upstream of Wilcannia for only the third time in 200 years and contributed to stored water volume in the Menindee Lakes.
In April 2010, the Murray–Darling Basin Authority (MDBA) assumed control of the water in the Menindee Lakes from the New South Wales Government. This occurred when their volume reached 640 GL (or 37% capacity). The Murray–Darling Basin Agreement states that New South Wales gains control when the volume of water in Menindee Lakes is less than 480 GL and the MDBA resumes control when the volume of water rises back above 640 GL. Therefore, the water sharing arrangements in the Murray–Darling Basin Agreement applies to the storage of the Menindee Lakes, which is shared among New South Wales, Victoria and South Australia.
The summer of the 2009–10 year resulted in record river flows and flooding on the:
Flooding also occurred in the lower reaches of the Border rivers region, upstream of Mungindi due to significant flows in the Weir River.
A new Department for Water commenced on 1 July 2010 to oversee the management of South Australia’s water resource.
From 1 July 2009, existing water licences in South Australia were unbundled and are now managed as four new and separate instruments: water access entitlement; water allocation; water resource works approval; and a site use approval. River Murray water licence holders were the first to transition to the new arrangements.
During 2009–10, a water allocation plan for Eastern Mount Lofty Ranges was developed.
The Victorian Minister for Water qualified water rights to meet essential human and environmental needs in some regions.
The water sharing plan for the New South Wales Border Rivers Regulated River Water Source commenced on 1 July 2009.
The 38 km Toowoomba Pipeline (capacity of 18,000 ML) was completed in January 2010, linking Wivenhoe Reservoir to Cressbrook Reservoir.
In June 2009, the Water for Good strategy was launched, which outlines actions to ensure South Australia water supplies are secure, safe, reliable and able to sustain continued growth – for at least the next 40 years.
The final Northern Region Sustainable Water Strategy was released. The Northern region includes Victoria’s share of the River Murray, and its Victorian tributaries – the Kiewa, Ovens, Broken, Goulburn, Campaspe and Loddon river systems.
The North–South Pipeline commenced operation in February 2010. The 70 km pipeline can transfer up to 75,000 ML from the Goulburn River to the Sugarloaf Reservoir (located on Melbourne’s outskirts).
The Wimmera–Mallee Pipeline Project was completed in April 2010. It involved building nearly 8,800 km of reticulated pipeline to replace 17,000 km of inefficient open channels, saving around 103,000 ML of water per year.
Joint Government Enterprise (Water for Rivers) – a New South Wales, Victorian and Australian Government initiative – recovered 217,704 ML of water by 30 June 2010 in the Murrumbidgee, Goulburn and Murray rivers for delivery of environmental flows in the Snowy River and the River Murray (MDBA 2011b).
The Australian Government had recovered (to be managed by the Commonwealth Environmental Water Holder) water entitlements through several programs. For example, 753,754 ML of water entitlement had been recovered by 30 June 2010 through the Restoring the Balance in the Murray–Darling Basin Program (MDBA 2011b).