Sustainable Diversion Limit
adjustment mechanism
The Sustainable Diversion Limit (SDL) adjustment mechanism is a process that Basin States agreed
on, that could change the volume of water recovery set under the Murray–Darling Basin Plan.
Through this process, we are trying to find smarter
ways of running the river system, while making
sure we have a healthy working Basin.
During the development of the Basin Plan prior to
2012, Basin water ministers requested that there be
an arrangement in place specific to the Southern
Basin, to provide flexibility with water recovery. This
arrangement is the SDL adjustment mechanism.
When the Basin Plan was implemented in 2012, the
sustainable diversion limit or SDL was set at 10,873
GL. This is the amount of water that can be used by
people from rivers in the Murray–Darling Basin. This
figure was agreed upon by all Basin States.
To reach this SDL figure, we have to return 2,750
GL of water to the river system to ensure a
sustainable future for generations to come. The
2,750 GL is known as the water recovery target.
To reach that target, the southern basin had to
contribute 2,289 GL, of which 1,682 GL has now
been recovered. The water we still need to recover
in the southern basin is 607 GL.
The remainder of the water recovery target will
come from the northern basin, and this is being
addressed through the Northern Basin Review.
Under the Plan, the SDL adjustment mechanism
could lead to a change to the water recovery figure
up or down by 5%.
This change is based on a series of new state
projects that use water more efficiently, allowing for
saved water to be returned back to irrigation or
environmental use.
State projects
Over the last few years, Basin state governments
have been putting forward new projects that look at
smarter river management practices and the more
efficient and effective use of water.
There are three types of projects:
1. River system projects that change the way the
system is managed to achieve equivalent
environmental outcomes using less water (eg
reconfiguring suitable lakes or storage systems
to reduce evaporation).
2. Water efficiency projects that provide more
water for the environment through efficient use
of irrigation water (eg lining channels to reduce
water loss within the irrigation network).
3. Projects that make changes to physical
structures or river management practices so we
can better deliver environmental water.
Funding is available for efficiency projects that
achieve the same or better social and economic
outcomes.
Take a look at the list of the projects which have
been proposed by Basin governments. For more
information about projects in your area, please
contact your state water agency.
State governments have until 30 June 2017 to put
forward projects and have committed to consulting
with their Basin communities.
The MDBA will calculate the amount of change to
the SDL from the package of proposals agreed by
the states.
Sustainable Diversion Limit adjustment mechanism
What is the 450 GL ‘up water’ and
650 GL ‘down water’?
In the Basin Plan, it notes that some
governments anticipated that by using
environmental water more efficiently, the new
river system projects would allow for the water
recovery target to be reduced by 650 GL.
However, that figure is greater than the 5%
outlined in the Plan.
Alternatively, the Plan also outlined that by
using water efficiency projects, we could get an
additional 450 GL of water for the environment
– as long as the result had the same or better
social and economic outcome.
So this means that the water recovery target
can’t go down by the full 650 GL amount,
without some movement ‘up’ as well.
Sustainable Diversion Limit adjustment
Making a change to the SDL
A draft determination, or any proposed
changes to the SDL and water recovery target
of 2,750 GL will be available for public
consultation in October 2017.
The MDBA will make a recommendation to the
Federal Minister for Water, the Hon. Barnaby
Joyce by 15 December 2017. A final decision
will need to be tabled in Parliament.
The decision will come into effect as state
Water Resource Plans are accredited and this
process will continue until 2019.
Approved projects under the SDL adjustment
mechanism process will be implemented from
2018 through to 2024.