The Murray–Darling Basin region

Annual rainfall across the Murray–Darling Basin (MDB) region was generally well below average for the 2012–13 year. These generally well below average rainfall conditions, compared to the well above average 2011–12 year, contributed to decreased inflows into the storages and a reduction of 5,175,406 ML in the volume of water held in storages over the 2012–13 year. Closing net water assets in the MDB region was 19,144,512 ML at the end of the 2012–13 year compared with 21,971,973 ML at the end of the 2011–12 year. For more information on the region's water assets refer to Water accounting statements.

Surface water met approximately 90% of the MDB region's water supply requirements over the 2012–13 year. This represented an increase of 3,216,580 ML from the previous year excluding environmental water use. The volume of groundwater extracted for water supply during the 2012–13 year was 1,209,782 ML, an increase of approximately 400,000 ML from the previous year. The increased use of surface water during the 2012–13 year was due to the abundance of surface water resources available for water supply (due to high storage volumes at the beginning of the year), coupled with the below average rainfall conditions over the year. The increased groundwater extraction was due to the increased demand resulting from below average rainfall conditions, combined with the abundance of groundwater resources resulting from increased recharge of aquifers in recent years.

The volume of surface water allocation trade (temporary trade) during the 2012–13 year was 5,985,629 ML, an increase of 46% from the previous year. This volume includes water traded for environmental delivery. Although there are many influencing factors on the trades, the abundance of surface water for allocation water trade and increased demands resulting from low rainfall were key contributing factors for the increased trade activity. In addition to surface water allocation trade, the volume of groundwater allocation trade within the region was 82,265 ML during the 2012–13 year. The volume of surface water entitlements permanently traded (intra-valley) within the MDB region during the 2012–13 year was 961,334 ML, a 13% decrease from the 2011–12 year.

Key water events within the MDB region during the 2012–13 year include South Australia receiving more than 900,000 ML of traded environmental water and increase in storage volume in Dartmouth Reservoir to 99% capacity in October 2012 the first time since 1997. Some of major water initiatives within the MDB region during the 2012–13 year were the adoption of the Murray–Darling Basin Plan in November 2012 and the commencement of seven water sharing plans for New South Wales catchments within the region. More information on significant water events and major water initiatives within the MDB region during the 2012–13 year is available in Significant water events and Major water initiatives.

The key water account information for the MDB region during the 2012–13 year is presented in the following table. Information on the uncertainty associated with the volumes presented in the table is provided in the relevant sections of the account.

 

Key water account information for the MDB region during the 2012–13 year

Contextual information: Climate overview

	2012–13	2011–12	Long–term average (1900–2012)
	Rainfall: 377 mm	Rainfall: 643 mm	Rainfall: 471 mm
	Evapotranspiration: 376 mm	Evapotranspiration: 559 mm	Evapotranspiration: 433 mm
For more detail on the MDB climate refer to Climate overview.

 

Contextual information: Water overview

	Murray River at Doctors Point (Albury)	Darling River at Bourke	Ovens River at Peechelba
	above mean annual flow	well below mean annual flow	just above mean annual flow
For more detail on streamflow in the MDB region refer to Water overview.

 

Water accounting statements

		2012–13	2011–12
	Total water assets as at 30 June (ML)	23,350,733	29,271,923
	Total water liabilities as at 30 June (ML)	4,206,221	7,299,950
	Change in net water assets (ML)	(2,827,461)	4,549,107
	Closing net water assets (ML)	19,144,512	21,971,973
For more detail on water assets and water liabilities refer to Water accounting statements.

 

Notes: Water resources and systems

 

Surface water storage

		30 June 2013		30 June 2012
	Total capacity	Volume	% of capacity	Volume	% of capacity
	23,193,359 ML	16,011,790 ML	69%	21,187,196 ML	91%
For more detail on surface water in the MDB region refer to Surface water.

 

Water abstractions

	Total water abstracted
	2012–13	2011–12	Recent activity
	Surface water: 10,687,045 ML	Surface water: 7,470,465 ML	Increased surface water (excludes environmental water use) and groundwater abstraction including for urban water systems.
	Groundwater: 1,209,782 ML	Groundwater: 810,060 ML
For more detail on the water abstraction in the MDB region refer to Surface water and Groundwater.

 

Urban water supply

	Total water supplied
	2012–13	2011–12	Recent activity
	415,695 ML	315,077 ML	Increased abstraction for urban water systems
For more detail on the urban water supplied in the MDB region refer to Surface Water and Groundwater.

 

Surface water trade

	Volume traded
	2012–13	2011–12	Recent activity
	Entitlement: 961,334 ML	Entitlement: 1,103,626 ML	Increased allocation trade and decreased entitlement trade
	Allocation: 5,985,629 ML	Allocation: 4,104,354 ML
For more detail on surface water trade in the MDB region refer to Water market activity.