Surface water

The Hunter river basin is a large river basin in coastal NSW with a contributing area of 21,437 km2, including a significant area in the north and east which falls outside the Hunter subregion boundary. The Hunter River rises in the Liverpool Ranges, and flows generally south and then west into Lake Glenbawn, created by the construction of Glenbawn Dam. Downstream of the dam, the Hunter River maintains a south-west direction to its junction with the Goulburn River before turning eastward towards Newcastle and the sea (Figure 3). Its five main tributaries, in terms of runoff contributions, include the Williams, Paterson and Goulburn rivers, Wollombi Brook and Glennies Creek.

Downstream of Glenbawn, Glennies Creek and Lostock dams, streamflow to and along the Hunter River is regulated by dam releases (Figure 3). Flow regulation means that streamflow is influenced by releases of water from the major storages. Elsewhere, streamflow is unregulated and the flow regime is primarily a response to rainfall.

The Macquarie-Tuggerah lakes basin contributes to the Lake Macquarie and Tuggerah Lakes systems of the NSW Central Coast, south-east of the Hunter river basin (Figure 3). The Macquarie-Tuggerah lakes basin covers an area of 1836 km2. In the north it contains a number of east-flowing streams, which rise in the Sugarloaf Ranges. To the south, the basin is bounded by the catchment divide with the Hawkesbury river basin. The Macquarie-Tuggerah lakes basin comprises the catchments of three main river systems: Dora Creek, Wyong River and Ourimbah Creek. Dora Creek flows into Lake Macquarie at the township of Dora Creek. To the south, the Wyong River and Ourimbah Creek catchments drain into Tuggerah Lake. These rivers are largely unregulated.

In a surface water account, water availability is defined in terms of water held in storages, including engineered storages and natural storages (e.g. the river itself) and/or volumes of water that are permitted to be extracted for consumptive use within a water management framework. Inflows are catchment runoff contributions to river flow, usually measured at tributary outlets or inflows to large storages. Outflows refer to river flows that exit the water accounting area, which in the Hunter subregion are mostly outflows to coastal lakes, estuaries and the sea, and actual extractions for use. The remainder of this section summarises for the Hunter river and Macquarie-Tuggerah lakes basins:

  • water volumes held in surface water storages
  • gauged surface water inflows and outflows
  • surface water entitlements and allocations to extract water
  • take and use of surface water.

Data for storages, inflows and allocations were available for different periods: water storage volumes were available for 1991 to 2012; stream gauging data for 2004–05 to 2011–12; allocations for 2004–05 to 2013–14; and water use for 2010–11 to 2013–14. The water accounts are thus indicative of recent climate conditions and water use practices.

A summary of data gaps relating to surface water accounts is provided at the end of the section.

Figure 3

Figure 3 Surface drainage network, dams and current streamflow gauges within the Hunter subregion

Regulated sections of the river network include Hunter River downstream of Glenbawn Dam, Glennies Creek downstream of Glennies Creek Dam and Paterson River downstream of Lostock Dam.

Data: Bioregional Assessment Programme (Dataset 1, Dataset 2, Dataset 3, Dataset 4)

Last updated:
18 January 2019