Officially, theyre called Sustainable Diversion Limit Offset Projects. In practice, that means upgrades to infrastructure or river operations to move water more efficiently.
The upshot is by moving water more efficiently, the volume needed for the environment can be reduced, which in turn minimises the size of cutbacks to irrigation entitlements.
The MDBA has calculated that 37 offset projects proposed by NSW, Queensland, Victoria and South Australia can reduce the Basin Plan recovery recovery target of 2750 gigalitres by 605GL.
Offset projects include new works on Victorias Belsar-Yungera Floodplain to increase the effectiveness of wetland inundation, reconfiguring weirs in Gunbower forest and rewriting state regulations to encourage water releases from storages at environmentally beneficial times.
Heres how the numbers work: the Basin Plan requires irrigation be cut to meet the Sustainable Diversion Limit of 10,873GL a year (the overall flow into the Basins waterways each year, on average, is 32,500GL by the way).
The Sustainable Diversion Limit is another way of saying the volume of water which the Murray Darling Basin Authority (MDBA) says is the amount that can be taken while maintaining a healthy river system.
MDBA calculations determined that irrigation should be reduced by 2750GL (the recovery target).
The bulk of the 2750GL, around 2100GL or so, has already been recovered through direct buybacks, or co-investments between the Commonwealth and farmers to swap water entitlements for on-farm upgrades.
