Northern Coast and Plains
This most northwestern part of the region, with its gently undulating plains and floodplains, is particularly vulnerable to the impacts of climate change. Its major towns, Gawler, Roseworthy, Mallala, Two Wells and Virginia are the focus of urban and industrial development, which could place further stress on its environmental assets.
Gawler has significant riparian assets; Roseworthy is a major grain-holding centre and has a campus of the University of Adelaide. Other centres support surrounding farming and horticulture, including significant glasshouse tomato production. The northern coastal areas are sparsely populated.
The salt fields at Dry Creek, along with constructed wetlands, support impressive visitation by migratory bird species, some of which are of international significance, and consequent tourism by bird watchers. This area now includes the Adelaide International Bird Sanctuary National Park - Winaityinaityi Pangkara.
Significant vegetation types include coastal and samphire shrubland, mangrove forest, and diverse mallee and shrubland on the plains. Coastal vegetation, especially in small areas, is a refuge for site specific flora and fauna but is threatened by human development and recreation. A number of plant communities, such as Peppermint Box grassy woodland, Iron-grass natural temperate grassland and Southern Cypress Pine woodland, are threatened, as are certain species of plants and animals.
The main rivers are the Lower Light and Gawler. The Light is an unregulated ephemeral river; the much more substantial Gawler River still has variable flows and terminates at Buckland Park Lake and on extensive tidal flats. Water quality in the Barker Inlet–Port River estuary complex has improved since 2000 with the decommissioning of the Port Adelaide Wastewater Treatment Plant and other initiatives including the construction of extensive wetlands to treat stormwater.
Groundwater supports industries in the subregion, most notably horticulture. Managed aquifer recharge is an important part of water resources management in the subregion. Longstanding cones of depression have stabilised in recent years with improved management.