Murray–Darling Basin

1.3 Regulated channel

Supporting information

The volumetric value for the line item at the end of 2009–10 is 970,657 ML.

This line item represents: (A) the volumes of water stored in the Murray river channel proper and (B) the volume of water held in weirs, other ponds and reservoirs in the Murray–Darling Basin region that are on regulated river channels.

Volumes stored in river channel

This data represents in-channel storage volume in the regulated River Murray system and the Lower Darling. This volume excludes the water held in locks and weirs. The regulated River Murray system also includes the Edward and Wakool rivers, and the associated escapes and channels.

Details of regulated river channel volumes in the Murray–Darling Basin
In-channel storage	01 July 2009 (ML)	30 June 2010 (ML)
River Murray	213,723	344,043
Edward and Wakool rivers	3,443	8,940
Lower Darling	956	2,745
Total	218,122	355,728

Volumes stored in river weirs and locks

Volumes held in the weirs and locks located in each region for which data are available are provided in the following table.

Details of volumes stored in weirs and locks in the Murray–Darling Basin
Region	Weir/lock name	Data source¹	Total capacity (ML)	Total storage (ML)		Total storage (%)²
Region	Weir/lock name	Data source¹	Total capacity (ML)	01 July 2009	30 June 2010	01 July 2009	30 June 2010
Condamine–Balonne	Buckinbah Weir	Bureau	5,120	5,060	4,190	99	82
Condamine–Balonne	Jack Taylor Weir	Bureau	10,270	7,285	8,534	71	83
Condamine–Balonne	Moolabah Weir	Bureau	2,580	2,022	2,006	78	78
Total Condamine–Balonne			17,970	14,367	14,730	80	82
Gwydir	Tareelaroi Weir	Bureau	2,500	445	1,043	18	42
Total Gwydir			2,500	445	1,043	18	42
Namoi	Gunidgera Weir	Bureau	1,900	1,508	1,212	79	64
Namoi	Mollee Weir	Bureau	3,250	760	101	23	3
Total Namoi			5,150	2,268	1,313	36	24
Goulburn–Broken	Goulburn Weir	Bureau	25,525	25,220	24,885	99	97
Total Goulburn–Broken			25,525	25,220	24,885	99	97
Loddon	Laanecoorie Reservoir	Bureau	7,932	345	1,698	4	21
Loddon	Newlyn Reservoir	Bureau	3,215	286	499	9	16
Total Loddon			11,147	631	2,197	6	20
Murrumbidgee	Berembed Weir	Bureau	3,415	1,170	428	34	13
Murrumbidgee	Hay Weir	Bureau	14,300	7,476	3,272	52	23
Murrumbidgee	Maude Weir	Bureau	4,920	1,402	4,683	28	95
Murrumbidgee	Tombullen	Bureau	11,230	369	343	3	3
Murrumbidgee	Gogeldrie Weir	Bureau	7,391	4,048	1,213	55	16
Total Murrumbidgee			41,256	14,465	9,939	35	24
Murray	Lock 1 – Blanchetown	Bureau	56,480	56,927	56,642	101	100
Murray	Lock 2 – Waikerie	Bureau	40,368	40,909	40,669	101	101
Murray	Lock 3 – Overland Corner	Bureau	50,533	50,175	51,148	99	101
Murray	Lock 4 – Bookpurnong	Bureau	29,366	29,320	29,491	100	100
Murray	Lock 5 – Renmark	Bureau	36,933	37,142	37,055	101	100
Murray	Mildura Weir	MDBA	36,586	36,755	36,671	100	100
Murray	Torrumbarry Weir	Bureau	36,809	36,897	36,817	100	100
Murray	Yarrawonga Weir – Lake Mulwala	Bureau	117,548	4,100	108,847	3	93
Murray	Lock 6 – Murtho	MDBA	33,882	32,234	34,088	95	101
Murray	Lock 7 – Rufus River	MDBA	10,227	9,924	10,783	97	105
Murray	Lock 8 – Wangumma	MDBA	14,984	15,105	14,140	101	94
Murray	Lock 9 – Kulnine	MDBA	32,938	32,938	33,824	100	103
Murray	Wentworth Weir (Lock 10)	MDBA	48,378	48,378	48,804	100	101
Murray	Euston Weir (Lock 15)	MDBA	21,807	21,824	21,842	100	100
Total Murray			566,839	452,628	560,822	80	99
Total MDB			670,387	510,024	614,929	72	86

1 Bureau = Bureau of Meteorology; MDBA = Murray–Darling Basin Authority

2 Total storage can be above 100% of total capacity when spilling

Quantification approach

Quantification approaches are provided separately for the river channels and weirs.

Volume stored in river channels

Data source

Upstream of South Australia border: volumes held on Murray–Darling Basin Authority (MDBA) HYDRO database.
Downstream of Lock 1: generated from levels held on MDBA HYDRO database and MDBA height–volume relationship.

Data provider

MDBA.

Method

Upstream of South Australia border: modelled.
Downstream of Lock 1: Interpolated from capacity table established by MDBA.

Uncertainty

Ungraded.

Assumptions, approximations and caveats/limitations

Reliable information on dead storage for the volumes upstream of the South Australian border is not available. Dead storage calculation within the reach is complex and is assumed to remain static over the years.
This data has not routinely been used by the MDBA and has been compiled specifically for this account.

Volume stored in weirs

Data source

Bureau of Meteorology: Water Storages, Australian Water Resources Information System (AWRIS).
MDBA: Hydro database.

Data provider

MDBA: River Murray weirs and locks (except locks 1 to 5), Torrumbarry Weir and Yarrawonga Weir.
Bureau of Meteorology: all other weirs and locks.

Method

Bureau of Meteorology

Storage volume was calculated at the start and end of the reporting period by using gauged water level height(s) (metres Australian Height Datum) for individual storages. The height measurement was converted to a volume using the storage-volume curve(s) of the storage.

The storage volume of individual storages was aggregated to present the total volume for the line item.

Murray–Darling Basin Authority

River levels were directly measured and converted into volumes using capacity tables for the individual locks.

Uncertainty

Bureau of Meteorology: ungraded.
MDBA: ungraded.

Assumptions, approximations and caveats/limitations

Bureau of Meteorology

Storage-volume curves represent specifically surveyed parts of the water storage, and may not reflect the storage-volume relationship across the entire storage.
Water storages are subject to sedimentation and other physical changes over time, which in turn affect the accuracy of the storage-volume curves.

Murray–Darling Basin Authority

The capacity of the lock is taken to be the volume contained in the lock at target storage/full supply level.
The dead storage associated with the locks is taken to be the volume in storage at the lower level of the operating range.
This approach allows for comparative measure across years and is preferred to estimating the total volume behind the lock wall, which cannot be accurately measured.
The accuracy of the capacity tables employed is ungraded.
Euston Weir volume excludes the Euston Lakes.

National Water Account 2010