MDB water market dataset

The MDB water market dataset covers the period of July 2000 to June 2020, and includes catchment regions across Australia, focussed particularly on the MDB. The MDB is split into northern (nMDB) and southern (sMDB) (Figure 1 ).  The nMDB covers QLD and northern NSW, while the sMDB covers southern NSW, ACT, Victoria and South Australia.

The list of regions in the Basin is outlined in Table 1, as well as if they are included in the Water Supply or Irrigation Activity datasets. In preparing the data, ABARES focussed on providing consistent time series data for key catchments and irrigation activities in the basin. However, this was not possible for all regions due to data limitations and gaps in coverage. Water Supply data has been collected for all MDB regions in NSW, Vic. and SA, but was not collected for QLD regions. Irrigation Activity data has been compiled for all catchments in Australia, but consistent time series are primarily available for catchments within the basin.

Region	MDB	Dataset
Barwon-Darling	nMDB	Demand
NSW Border Rivers	nMDB	Demand, Supply
Gwydir	nMDB	Demand, Supply
Lachlan	nMDB	Demand, Supply
Macquarie-Castlereagh	nMDB	Demand, Supply
Namoi	nMDB	Demand, Supply
QLD Border Rivers	nMDB	Demand
Condamine-Balonne	nMDB	Demand
Moonie	nMDB	Demand
Warrego-Paroo	nMDB	Demand
Australian Capital Territory	sMDB	Demand
Lower Darling	sMDB	Demand, Supply
NSW Murray Above (Above Barmah Choke)	sMDB	Demand, Supply
NSW Murray Below (Below Barmah Choke)	sMDB	Demand, Supply
Murrumbidgee	sMDB	Demand, Supply
Adelaide and Mount Lofty	sMDB	Demand
South Australian Murray	sMDB	Demand, Supply
Goulburn-Broken	sMDB	Demand, Supply
Loddon-Campaspe	sMDB	Demand, Supply
VIC Murray Above (Above Barmah Choke)	sMDB	Demand, Supply
VIC Murray Below (Below Barmah Choke)	sMDB	Demand, Supply
Ovens	sMDB	Demand
Werribee	sMDB	Demand
Wimmera-Avon	sMDB	Demand

Source: ABARES

The MDB water market dataset offers a number of improvements over previous datasets released by ABARES. For example, the Water supply file includes additional variables, such as forfeited water (split by during year, and end of year), which allows for more accurate estimations of total water supply. To our knowledge, the Irrigation Activity file is the first comprehensive catchment level dataset for water use, area irrigated and production, and is the result of close collaboration with the ABS.

The construction of the MDB water market dataset involved considerable effort, given the large number of data sources and various inconsistencies between them. A number of data imputations, assumptions and regression estimations were required, in addition to filling gaps through external data sources in order to generate time series data for a consistent set of regional and industry definitions.

The final datasets draws from various sources, which are further detailed in the metadata spreadsheets accompanying this product.

Irrigation Activity

The Irrigation Activity file contains data for each of the variables listed in Table 2 for financial years from 2005–06 to 2018–19. ABARES has worked extensively with the ABS to create a custom catchment level dataset of irrigation activity. This dataset has been built from unit-record data collected through various agricultural censuses and surveys, and provides irrigation activity data for catchment regions across Australia from 2010–11 onwards. For the period 2005–06 to 2010–11, ABARES apportioned Natural Resource Management (NRM) level public data to catchment regions, using methods previously described in Gupta et al. 2018. The apportioning method was calibrated using data provided by the ABS for 2010–11 to 2012–13.

Variable	Description	Units
Area watered	Area of irrigation by region and industry	Ha
Volume applied	Volume of irrigated water applied total	ML
Production	Volume of irrigated production.  For commodities Almonds, Cotton, Rice and Grapevines production is recorded as kg.  For all other commodities production is reported as an index value	kg
Commodity price	Nominal commodity prices.  For commodities Almonds, Cotton, Rice and Grapevines prices are recorded as $/kg.  For all other commodities prices are reported as an index value	$
GVIAP	Nominal dollar value of irrigated agricultural production	$
Area_br	Area of bearing grapevines	Ha
Area_nbr	Area of non-bearing grapevines	Ha
Tree_br	Number of bearing almond trees	No.
Tree_nbr	Number of non-bearing almond trees	No.
K_Almonds	The total number of bearing trees as a proportion of total almond trees	%
L_meta	Metadata for Area_watered	Value
W_meta	Metadata for Volume_applied	Value
Q_meta	Metadata for Production	Value
K_meta	Metadata for K_Almonds	Value
Y_meta	Metadata for Commodity_price	Value

Source: ABARES

Table 3 lists the irrigation activities considered in the demand file. Irrigation activities are based on ABS industry classifications. A significant feature of the MDB water market dataset is that it separately reports data for the almonds industry, which is elsewhere part of the combined fruit and nut category reported by the ABS.

Almonds	Pasture for hay
Cotton	Rice
Dairy	Other broadacre
Fruits	Other cereals
Grapevines	Other crops
Pastures for grazing	Vegetables

Source: ABARES

For regions within the MDB, where data was missing (for example, due to ABS confidentiality constraints) ABARES has estimated values. ABARES has used a variety of methods to impute missing data, as listed in Table 4. All imputed data points are marked in additional columns in the dataset (denoted with the "meta" suffix) and remain subject to further refinement.

Value	Description
1	ABS unit-level data constructed and cleared by ABARES.
2	Catchment data approximated by ABARES using ABS NRM level data for 2006 to 2010.
3	Missing values filled with a linear interpolation
4	Missing values filled with ABARES regression results
5	Data obtained from external sources
6	Missing data that was not filled using other methods
7	ABARES estimate
8	Price index
9	$/kg

Source: ABARES

Water supply

The Water Supply file was compiled using data from the MDBA, state water agencies (NSW Department of Planning, Industry and Environment, Goulburn-Murray Water, Northern Victorian Resource Manager and the South Australian Department for Environment and Water), BOM and the Department of Agriculture, Water and the Environment (DAWE). Water price data has been compiled and cleaned by ABARES using the GAM price cleaning method described in Sanders et al. 2019.

Each of the variables included in the Water Supply file are briefly described in Table 5, which contains data for catchments in the MDB from 2000–01 to 2019–20.

Name	Description	Units	Source
Entitlement volumes	Water entitlements are an ongoing right to access a share of water. They are equal to a nominal volume of water for different types of reliability, and are able to be traded or held for potential use.	ML	State water availability reports
Allocation percentages	The percentage for each entitlement type that is able to be accessed during a water year or a particular period. For combined regions (i.e. Vic. Goulburn-Broken) allocation percentages are derived by calculating the combined regional allocation volume, divided by the combined regional entitlement volume.	%	State water allocation announcements
Uncontrolled flow usage	Uncontrolled flow events occur when there is a water flow that is not able to be controlled, and is greater than the amount allocated for consumption or environmental needs. During this time anyone is allowed to access the water. The volume accessed for use is considered the uncontrolled flow usage.	ML	New South Wales Available Water Determination (‘AWD’) Reports
Allocation volume	A water allocation is the right to access a volume of water during a water year. It is equal to the entitlement volume multiplied by allocation percentages for each entitlement type.	ML	State water allocation announcements, state water availability reports, NSW AWD reports
Within year forfeits	Water users can sometimes lose water from evaporation or other causes. When this occurs the volume lost is considered a within year forfeit.	ML	Victorian unused water reports, NSW General Purpose accounting and AWD reports
End of year forfeits	End of year forfeits are equal to the total volume of water that has not been used in the water year or carried over into the next year.	ML	VIC Unused water reports,  NSW General Purpose accounting, and AWD reports
Carryover from previous year	The total volume of allocation water individual water right holders have held in storage to carry over from the previous year.	ML	NSW Department of Primary Industries, Northern VIC Resource Manager, South Australia Department for Environment and Water, Vic. Water Register
Environmental buyback entitlement volumes	Total volume of entitlements purchased for the environment by the Commonwealth Environmental Water Holder (CEWH).	ML	DAWE
On-Farm Infrastructure programs entitlement volumes	Total volume of entitlements recovered for the environment through on-farm infrastructure programs.	ML	DAWE
Off-Farm Infrastructure program entitlement volumes	Total volume of entitlements recovered for the environment through off-farm infrastructure programs.	ML	DAWE
Delta	The sum of entitlement volumes recovered for the environment from buybacks and on-farm infrastructure programs as a proportion of the total volume of entitlements.	%	ABARES estimate
Price of water allocations	Average annual real (2018–19$) allocation price.	$/ML	BOM national water register. Data was cleaned using ABARES price cleaning scripts.
Net allocation water trade from CEWH to irrigators	Total volume of water sold from the CEWH to irrigators.		CEWH
Net allocation water trade (excluding environmental trade)	Total volume of allocation water traded into a catchment region subtracted by the total volume of water traded out of it.	ML	MDBA provisions, Victorian Water Register
Water Use	Calculated field estimating total water use by catchment by year	ML	ABARES estimate