2.7.7 'Springs' landscape group

Summary

The ‘Springs’ landscape group is comprised of two landscape classes: ‘Great Artesian Basin (GAB) springs’ and ‘Non-GAB springs’. The distinction between these two landscape classes is based on the hydrological connectivity of the spring to the underlying aquifer. The ‘GAB springs’ landscape class is associated with sedimentary sequences of the GAB. Based on their hydrogeological setting and related flow paths, the ‘GAB springs’ springs can be characterised as ‘discharge’ or ‘recharge’ springs.

Two of the seven ‘GAB springs’ in the Namoi assessment extent are located within the zone of potential hydrological change. Given their location on the eastern edge of the Pilliga region, these springs were interpreted to be recharge springs.

A qualitative model was formulated for a typical recharge GAB spring that included the associated terrestrial and aquatic ecosystems. This model identified groundwater drawdown as the critical variable driving ecological function in this system. Given the nature of these springs and their limited extent in the zone of potential hydrological change, a receptor impact model was not formulated for this group.