Temperate Highland Peat Swamps on Sandstone (THPSS) are distinctive feature of low-relief plateau areas in south eastern Australia and are key features of water supply catchments in this area. Coincidentally, the areas in which THPSS are concentrated, in the Blue Mountains and Southern Highlands of NSW, occur in the water supply catchments for Sydney. These THPSS play a role in determining the quantity and quality of water in those catchments. THPSS are also listed as an endangered ecological community under the National Environment Protection and Biodiversity Conservation Act 1999, and the NSW Threatened Species Conservation Act 1995, and are threatened by activities such as long wall mining, coal seam gas extraction and catchment urbanisation.
Recent recognition of the value of these systems has prompted policy that places priority on the conservation and maintenance of intact swamps, and reinstatement of swamps where they have been degraded or destroyed. However, these activities are occurring without a sound knowledge of the geomorphic structure, function and Holocene evolution of these systems. This understanding provides the physical template atop which a range of biological, hydrological and chemical interactions occur. It is timely that THPSS, as an integral part of the catchment water cycle, are well understood. Based on 18 study sites we present a regional model of THPSS structure, function and age structure, and discuss implications for biodiversity conservation and rehabilitation.