Protecting water quality in urban estuaries: Australian case studies

Estuaries provide important environmental, social, cultural, and economic services. The provision of these services is often negatively impacted by urban development within the catchment and along shorelines, most notably through habitat loss and alteration of hydrological and sedimentation regimes influencing system structure and function. Mitigating the effects of urban development on estuaries provides a great challenge for managers, particularly when considering the diversity of estuaries and catchment characteristics. The management of urban stormwater is a challenging issue where no single solution is apparent but requires varied approaches. Using three distinctly different Australian estuaries, this chapter presents an account of combined management plans, restoration, monitoring/research, and education efforts used in addressing and managing the issues of urban pressures on water quality surrounding Port Jackson, Gold Coast Broadwater, and the Ross River estuary. Although the case study estuaries significantly vary according to rainfall seasonality and intensity, population density, and catchment size, a survey of implemented protection and management initiatives, illustrates a consistent theme of management practices across the case studies: (1) catchment/estuary management policies and plans including stormwater quality improvement device initiative practices; (2) low impact and purpose-designed development options including water-sensitive urban design options, including specific design adaptations required for effective operation in varying climatic zones and catchment conditions; (3) restoration programs; (4) water quality monitoring programs; (5) research activities; and (6) stakeholder and community education campaigns. The best management outcomes for urbanized estuaries require implementation of catchment-based management plans that are supported by clear objectives regarding ecosystem services and regional challenges