Many people are unaware of the importance of groundwater, which provides more than 20% of the water used in Australia.  Surface water (lakes, rivers, streams) and groundwater are often though of as being separate resources but in many catchments they represent a single connected system.  Rachel’s PhD project aims to develop a model of surface and groundwater interactions in the Namoi Catchment, located in northern New South Wales.  The model will contribute to a project assessing social, economic and ecological impacts of scenarios including a varying climate, water policy options and adaptations in land management practises.