Increasing urbanisation of coastal areas is placing unprecedented pressure on estuarine environments. Impacts associated with urbanisation can alter the health of estuarine ecosystems, reducing their capacity to provide valuable ecosystem services. In order protect these environments, relationships between estuarine health and urbanisation should be understood and applied to sustainable urban planning in coastal areas. Responses measured in estuarine biota offer much potential for providing pragmatic and sensitive means for the detection of urban impacts in estuaries. I assessed the responses of estuarine biota to increasing levels of urbanisation in the rapidly developing coastal region of southeast Queensland, Australia. I measured a suite of biotic indicators, namely: the [delta-N-15] of mangroves and crabs as a tracer for urban N sources, sediment chlorophyll a concentration (Chl a) as an estimate of the biomass of microphytobenthos (MPB), and a condition index in crabs, measured as the hepatosomatic index (HI). Urbanisation was estimated as the percentage of catchment covered by impervious surfaces (impervious cover, IC). Increases in impervious surfaces such as roads, footpaths and car parks are closely linked to urbanisation. These surfaces concentrate and convey pollutants generated from urban activities into coastal waterways and estuaries, thus making IC a useful indicator of urban impact.