Floating wetland treatment systems (FWTS) are an innovative stormwater treatment technology currently being trialled on a larger scale in Australia. FWTS provide support for selected plant species to remove pollutants from stormwater discharged into a water body. The plant roots provide large surface areas for biofilm growth, which serves to trap suspended particles and enable the biological uptake of nutrients by the plants. As FWTS can be installed at the start of the construction phase, they can start treating construction runoff almost immediately. FWTS therefore have the potential to provide the full range of stormwater treatment (e.g. sediment and nutrient removal) from the construction phase onwards. A 2,100m 2 FWTS has been installed within a greenfield development site on the Sunshine Coast, Queensland. A four-year research study is currently underway which will target the following three objectives; (1) characterise the water quality of runoff from a greenfield development in the construction and operational phases; (2) verify the stormwater pollution removal performance of a FWTS during the construction and operational phases of a greenfield development; and (3) characterise the ability of FWTS to manage urban lake health. This extended abstract presents the proposed research methodology and anticipated outcomes of the study
MULTIFILE
In recent years, there has been a steady increase in the number of bioretention systems installed worldwide. However, there has only been limited research on the long-term effectiveness of these sustainable urban drainage system devices. This paper presents the results of a series of controlled field experiments investigating the pollutant removal efficiency of three bio-filtration system that have been in service for over five years in the Sunshine Coast in Australia. The results of this study suggest that the long-term pollution removal performance of these systems may not be as effective as previously thought and further research is needed.
Storm sewers are known to significantly contribute to annual pollutant loads to receiving water bodies. The storm sewers of the city of Almere discharge the stormwater of 1384 ha of impervious area via 700 storm sewer outfalls (SSOs) to the local receiving water system. This water system suffers from eutrophication and long term build-up of pollutant levels in the sediment bed. In order to be able to select the most effective stormwater management strategy, the municipality of Almere and Water Authority Zuiderzeeland have launched a 2 year extensive monitoring project to measure the stormwater quality and the potential impact of source control and end of pipe measures to decrease the emission via SSOs. Source control measures, such as removal of illicit connections and increasing the cleaning frequency of gully pots showed to be most effective. The potential impact of end of pipesolutions based on settling showed to be very limited due to the low settleability of solids in the storm water of Almere at the SSOs.
INXCES will use and enhance innovative 3D terrain analysis and visualization technology coupled with state-of-the-art satellite remote sensing to develop cost-effective risk assessment tools for urban flooding, aquifer recharge, ground stability and subsidence. INXCES will develop quick scan tools that will help decision makers and other actors to improve the understanding of urban and peri-urban terrains and identify options for cost effective implementation of water management solutions that reduce the negative impacts of extreme events, maximize beneficial uses of rainwater and stormwater for small to intermediate events and provide long-term resilience in light of future climate changes. The INXCES approach optimizes the multiple benefits of urban ecosystems, thereby stimulating widespread implementation of nature-based solutions on the urban catchment scale.INXCES will develop new innovative technological methods for risk assessment and mitigation of extreme hydroclimatic events and optimization of urban water-dependent ecosystem services at the catchment level, for a spectrum of rainfall events. It is widely acknowledged that extreme events such as floods and droughts are an increasing challenge, particularly in urban areas. The frequency and intensity of floods and droughts pose challenges for economic and social development, negatively affecting the quality of life of urban populations. Prevention and mitigation of the consequences of hydroclimatic extreme events are dependent on the time scale. Floods are typically a consequence of intense rainfall events with short duration. In relation to prolonged droughts however, a much slower timescale needs to be considered, connected to groundwater level reductions, desiccation and negative consequences for growing conditions and potential ground – and building stability.INXCES will take a holistic spatial and temporal approach to the urban water balance at a catchment scale and perform technical-scientific research to assess, mitigate and build resilience in cities against extreme hydroclimatic events with nature-based solutions.INXCES will use and enhance innovative 3D terrain analysis and visualization technology coupled with state-of-the-art satellite remote sensing to develop cost-effective risk assessment tools for urban flooding, aquifer recharge, ground stability and subsidence. INXCES will develop quick scan tools that will help decision makers and other actors to improve the understanding of urban and peri-urban terrains and identify options for cost effective implementation of water management solutions that reduce the negative impacts of extreme events, maximize beneficial uses of rainwater and stormwater for small to intermediate events and provide long-term resilience in light of future climate changes. The INXCES approach optimizes the multiple benefits of urban ecosystems, thereby stimulating widespread implementation of nature-based solutions on the urban catchment scale.
