The context statement brings together what was known about the geography, geology, hydrology and ecology of the Hunter subregion as at April 2015.
The Hunter subregion spans an area of about 17,045 square kilometres and is home to about 838,000 people. It extends north from Broken Bay on the New South Wales Central Coast to just north of Newcastle. Other important regional urban centres include Maitland and Cessnock.
The subregion is primarily defined by the geological Sydney Basin and the river basins of the Hunter River and the Macquarie-Tuggerah Lakes, which are in part defined by ridge lines associated with the Hunter Range, Liverpool Range and Great Dividing Range. The Hunter is the major river in the subregion.
A significant proportion of New South Wales electricity is generated by coal-fired power stations located in the Hunter subregion and fuelled with locally mined coal.
About 40% of land in the subregion is used for agricultural production.
The Hunter subregion is within the geological Sydney Basin and the minor Werrie Basin, which in turn form part of the Permian-Triassic Sydney-Gunnedah-Bowen Basin. This basin formed approximately 230 to 310 million years ago and extends some 1700 kilometres from southern New South Wales to central Queensland.
Three coalfields are contained within the Hunter subregion: the Hunter, Newcastle and Western coalfields.
The relatively small Werrie Basin also contains a terrestrial coal-bearing unit.
Surface water and groundwater
The Hunter subregion contains rivers that flow into two major river basins: the Hunter river basin and the Macquarie Tuggerah basin. There are a number of dams within the Hunter subregion built for flood mitigation, hydro-electric power, irrigation, water supply and conservation.
The Hunter Valley Alluvium aquifer is an important groundwater resource supplying up to 80.4 gigalitres of water per year under licence.
The rainfed Tomago Tomaree Stockton Sandbeds, located between Newcastle and Port Stephens, are another important water resource for the Newcastle area.
The Hunter Valley is of great ecological significance. It represents the only major break in the Great Dividing Range, which provides a link between coastal and inland New South Wales, and includes an overlap between tropical and temperate climate zones. The subregion includes Tuggerah Lakes, Lake Macquarie, and large sections of Goulburn River National Park. The lower Hunter Valley contains the internationally recognised Hunter Estuary Wetlands.
The Hunter subregion contains 27 endangered ecological communities, eight endangered populations and 116 threatened animal species, listed under New South Wales legislation, of which 33 are also listed under Commonwealth legislation. Twelve groundwater-dependent ecosystems have been identified in the Hunter subregion.
- 1.1.1 Bioregion
- 1.1.2 Geography
- 1.1.3 Geology
- 1.1.4 Hydrogeology and groundwater quality
- 1.1.5 Surface water hydrology and water quality
- 1.1.6 Surface water – groundwater interactions
- 1.1.7 Ecology
- Contributors to the Technical Programme
- About this technical product