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The present study investigates 45 natural and artificial water bodies extending across the whole of eastern Australia from the tropics to Tasmania. A broad variety of physio-chemical, land-use and climatic parameters were measured. Reservoirs and other artificial water bodies responded to stressors in their catchments in a similar fashion to natural lakes, but tended to be less nutrient rich, possibly because of shorter residence times and active management. Salinity and pH were strongly correlated in the dataset. Bedrock had a strong influence on pH in freshwater lakes, whereas all highly saline lakes were alkaline, irrespective of bedrock. High concentrations of anions in saline lakes precluded the existence of acid conditions by binding available hydrogen ions. Almost all lakes fell on salinity axes that indicated marine origin for their salts. An assessment of the total nitrogen to total phosphorus molar ratios from the lakes in the present dataset indicated that productivity in Australian lakes could be limited by both nitrogen and phosphorus. Future research using macro-nutrient enrichment experiments should be pursued to confirm this preliminary observation. There was a strong positive correlation between regional aridity and lake eutrophication. This is typical of semi-arid and seasonally arid environments and reflects the concentration of nutrients owing to evaporative flux in shallow basins with high residence times.