Resource assessment process

When determining how much water will be allocated to water users, there are number of considerations, including:

  • how much water is in storage and how much of that is carried over as unused water from the previous year, including undelivered inter-state trades, where applicable
  • how much water is expected to flow into storages from natural inflows over the forecast period
  • the volume required to run the river, including end of system flows, transmission losses and evaporation losses
  • other requirements, including storage reserves and credits to environmental water allowances, where applicable.

In making the water resource assessment, the lowest recorded inflow sequence as at the commencement of the first water sharing plan is used so that the department only allocates water that is very likely to flow into the storages. Not all inflows contribute to increasing allocations.

Water allocation guides for major river valleys

To help people understand the way in which water is allocated to the various priorities and licence types, the department is developing guides on how the water allocation process works in each of the major regulated river valleys – see respective guides below.

Process map of how water is allocated

Below is a simple overview of how water is allocated in valleys in NSW.

Process map of how water is allocated

Download a larger diagram (JPG, 272.09 KB)

Detailed information on how water is shared in the regulated Murrumbidgee and Murray valleys, as well as the Hunter regulated river water source in NSW is provided in the fact sheets below.

How water is allocated and shared between the Murray and Menindee Lake

Watch this short video.

How are water losses calculated?

Watch this short video.

How water allocations change

Watch this short video.