Murray-Darling Basin
28.1 Precipitation on landscape

The volumetric value for the line item for the 2010–11 year was 819,237,686 ML. The line item represents the volume of all forms (rain, sleet, snow, hail, or drizzle) of water falling on the landscape within the Murray–Darling Basin (MDB) region. The following table presents breakdown information for the volumetric value on sustainable diversion limit (SDL) area basis.

 

Precipitation on the landscape in the MDB region for the 2010–11 year

Water resource plan area	SDL area		Jurisdiction	Volume (ML)
	Code	Name
SW19 Warrego – Paroo – Nebine	SS29	Paroo	Qld	19,065,188
	SS28	Warrego	Qld	53,666,963
	SS27	Nebine	Qld	22,374,907
SW18 Condamine–Balonne	SS26	Condamine–Balonne	Qld	85,537,248
SW17 Moonie	SS25	Moonie	Qld	11,890,467
SW16 Qld Border Rivers	SS24	Qld Border Rivers	Qld	21,146,789
SW15 NSW Border Rivers	SS23	NSW Border Rivers	NSW	20,002,724
SW11 Barwon–Darling Watercourse	SS19	Barwon–Darling Watercourse	NSW	2,172,260
SW12 NSW Intersecting Streams	SS17	NSW Intersecting Streams	NSW	71,458,914
SW14 Gwydir	SS22	Gwydir	NSW	22,857,455
SW13 Namoi	SS21	Namoi	NSW	34,340,142
SW10 Macquarie–Castlereagh	SS20	Macquarie–Castlereagh	NSW	68,818,257
Sub-total Northern Basin				433,331,315
SW9 Lachlan	SS16	Lachlan	NSW	64,534,200
SW8 Murrumbidgee	SS15	Murrumbidgee NSW	NSW	72,805,800
SW7 NSW Murray and Lower Darling	SS18	Lower Darling	NSW	67,482,184
	SS14	NSW Murray	NSW	17,030,106
SW2 Vic Murray	SS3	Kiewa	Vic	3,370,891
SW3 Northern Victoria	SS4	Ovens	Vic	12,174,382
	SS5	Broken	Vic	4,563,407
	SS6	Goulburn	Vic	20,513,020
	SS7	Campaspe	Vic	4,581,014
	SS8	Loddon	Vic	12,608,065
SW2 Vic Murray	SS2	Vic Murray	Vic	20,346,078
SW4 Wimmera–Mallee	SS9	Wimmera–Mallee	Vic	44,652,240
SW6 Eastern Mount Lofty Ranges	SS13	Eastern Mount Lofty Ranges	SA	2,018,812
SW5 SA Murray	SS11	SA Murray	SA	725,488
	SS10	SA Non-prescribed areas	SA	35,134,029
SW6 Eastern Mount Lofty Ranges	SS12	Marne–Saunders	SA	490,307
SW1 ACT	SS1	ACT	ACT	2,876,347
Sub-total Southern Basin				385,906,371
Total for the region				819,237,686

 

Bureau of Meteorology (the Bureau): Australian Water Availability Project (AWAP) monthly precipitation grids.

The Bureau.

Monthly precipitation data was produced by the Bureau of Meteorology. It was based on daily data from approximately 6,500 rain gauge stations and interpolated to a 0.05 degree (approximately 5 km) national grid (Jones et al. 2007).

The average precipitation depth across the MDB landscape was determined as the weighted mean of precipitation occurring onto the relevant grid points within the region boundary. Points were weighted upon the area they represented within the MDB landscape to remove edge effects (where the area represented was not wholly within the MDB region) and the effect of changing area represented with changing latitude. The depth of precipitation was converted to a volumetric estimate by multiplying by the total area of the MDB landscape.

Only precipitation falling onto the landscape was considered in the line item. Precipitation falling onto storages, lakes, off-channel water storages and other water bodies was not included.

The precipitation estimates were subject to approximations associated with interpolating observation point data to a national grid detailed in Jones et al. (2007).

The uncertainty estimate was not quantified.

There was no comparative line item in the 2010 Account.  The relevant volume calculated for the 2009–10 year was 559,425,235 ML.