Giamba Bussi and colleagues have used INCA model to develop a decision support system to assess water quality impacts in urban rivers. Poor water quality is a widespread issue in urban rivers and streams throughout the world. Localised pollution can have impacts on local communities, from health issues to environmental degradation and restricted recreational use of water. The Salmons and Pymmes Brooks, located in London UK, have significant pollution impacts from misconnected sewers, urban runoff and atmospheric pollution. The first step towards finding sustainable and effective solutions to these issues is to identify sources and paths of pollutants and to understand their cycle through catchments and rivers. The team applied INCA to the two urban catchments with the aim of providing local communities and community action groups such as Thames21 with a tool they can use to assess the water quality issue. They evaluated a set of mitigation strategies including constructed wetland across the catchment to assess pollution control. Constructed wetlands can make a significant difference reducing sediment transport and improving nutrient control for nitrogen and phosphorus. This study showed that a substantial reduction in nitrate, ammonium and phosphorus concentrations can be achieved if a proper catchment-scale wetland implementation strategy is put in place. Furthermore, nutrient reduction efficiency of the wetlands should not be affected by climate change.