To manage stormwater in an adaptive way as well as improving the mitigation strategies to cope with the climate change and urbanisation impacts, Water Sensitive Urban Design (WSUD) approaches are becoming popular. Most of the exiting research in this area has been focused on implementation in infill developments or greenfield sites. Thus, significant knowledge gaps exist in the implementation of WSUD approaches within existing urban areas with holistic approaches. This research will investigate the optimal implementation of WSUD approaches in existing urban development.

PhD Thesis underway by Samira Rashetnia.

Growing populations and climate change place increased pressures on our water supplies. Stormwater harvesting and reuse offers a potential option to augment traditional water resources. Before it can be utilised within a given context, however, its safety must be established. This project developed a Bayesian Belief Network (BBN) model representing pathogen sources and treatment barriers within a proposed stormwater harvesting scheme. The BBN can utilise a range of data sources and be constantly updated to assist managers to engage effectively with stakeholders and identify the most appropriate combination of risk management strategies available to them.

Honours Thesis completed by Dean Albert Mensinga in October 2019.

The Stormwater Industry Association of Australia (SIA) formulated a draft Stormwater Quality Improvement Device Evaluation Protocol (SQIDEP) proposed for use in validation of stormwater treatment devices. This was presented to some Victorian water industry and regulatory parties for comment in February 2016. The project’s aim was to provide scientific support for the guidance and/or scientifically supported alternative advice.

The purpose of this review was to investigate scientific literature related to stormwater protocols that can add value to the SQIDEP before its official release in 2018. A number of other international stormwater device evaluation protocols were also investigated. A scientifically defensible protocol would add value to the Australian stormwater industry and allow manufacturers and product end users to have confidence in the process used to assess stormwater treatment devices.

Overall a number of recommendations were proposed to improve the Australian-based protocol. These included: increasing the minimum number of storm events; increasing event coverage; reviewing some of the recommended performance metrics; sampling and analysis for suspended total solids, suspended solids concentration and particle size distribution as well as a range of other pollutants; providing target removal levels for suspended solids based on Australian guidelines; sampling some sequential storm events; and inclusion of operation and maintenance requirements and schedules.

Raw source water contains parts of plants, blue-green algae and their toxins, and many other types of organic matter. Identifying the types and amounts of organic matter helps treatment plant operators make informed decisions about the most efficient and cost-effective methods for treating and removing unwanted substances from source waters. The problem is that many of the tests for identifying organic compounds can take hours to days to deliver results. This research developed a test that gives information immediately. It uses three commercially available fluorescent probes that each emit fluorescent light at a specific wavelength. Certain compounds within organic matter, such as proteins, “reflect” the fluorescent light, but at different wavelengths which can be detected by the probes. These patterns of “reflected” fluorescence were related to traditional tests for organic compounds. This on-line fluorescence monitoring was then trialled at real-world treatment plants. The patterns gave reliable information about broad categories of organic compounds and there was a linear correlation between dissolved organic carbon and fluorescent intensity in both raw and treated waters. This research has provided a valuable addition to the suite of tools available for producing safe, high quality drinking water.

This project formed the Mekong node of the Collaboration on Sewage Surveillance for SARS-CoV-2 “ColoSSoS” project after Water Research Australia and the Australian Water Association identified that technology transfer within Australia’s broader region was a logical extension of the local project.

This project transferred leading Australian innovation in the environmental surveillance of SARS-CoV-2 to support the Governments of five countries in the Mekong River Delta (including Vietnam, Cambodia, Laos, Myanmar, and Thailand) to prepare, respond and recover from the COVID-19 pandemic. It established partnerships between Australia and these five countries and transferred SARS-CoV-2 environmental surveillance methods established in Australia by WaterRA and partners. The transfer of these methods has supported each Government’s efforts to monitor SARS-CoV-2 prevalence in water environments (primarily sewage and stormwater), to inform COVID-19 control strategies of the Governments and add to their COVID-19 resilience toolbox. Through developing the set-up for potential cost-effective earlier warning detection systems for COVID-19 outbreaks in each country, the project has supported the long-term strengthening of health security, systems, stability, social cohesion and economic recovery across the Mekong region.

The standards for recycling stormwater are higher for drinking water than for non-potable reuse such as agricultural or urban irrigation. The Australian Drinking Water Guidelines (ADWG) inform regulations that ensure the removal of infectious pathogens and polluting chemicals from potable water, whereas the Australian Guidelines for Water Recycling (AGWR) ensure that non-potable recycled water does not pose a risk to human health. Compliance with these Guidelines often requires quantitative risk assessment of stormwater catchments, but this is an expensive and resource-intensive process. This research developed a ‘Chemical Hazard Assessment of Stormwater Micropollutants’ (CHASM) desktop tool to assess the suitability of stormwater for various potable and non-potable uses before commencing an expensive risk assessment, and to guide design of optimal and targeted monitoring and measuring programmes for chemicals of concern in any given catchment. Basic information about each of four Australian stormwater catchments (including size, land-use, and surface types) was entered into CHASM Excel spreadsheets. The tool utilises a database to generate a list of likely pollutants for that catchment, and optimal locations and times for monitoring. The CHASM tool proved reliable and easy to use.

The ‘One Water’ paradigm recognises the interconnectedness of groundwater, stormwater, wastewater, flooding, water quality, wetlands, watercourses, estuaries, and coastal waters, and integrates multi-use, flexible and environmentally sustainable systems while valuing all urban water flows as a potential resource. Decades of water production, sewage treatment and urban development, have resulted in pipe and pump-station networks with the associated procedural systems for regulation and governance. Altogether, these form barriers to ‘One Water’ recycling and reuse. This research investigated, described, and defined these barriers and the strategies and actions used to overcome them. This was accomplished by reviewing published literature, by collating case studies and by recording the outputs of interactive workshops. It was concluded that obstacles to ‘One Water’ include the existing system of centralised and silo-ed expertise and the current complex structure of regulations governing safety of water supply, wastewater, and stormwater management. Research findings were used to develop a framework for transitioning to more flexible ‘One Water’ management processes which focus on integrated resource planning, incremental implementation, and the collaboration of traditional urban planners with water resource managers.

Stormwater and treated wastewater can contain infectious pathogens. The Australian Guidelines for Water Recycling (AGWR) require that these are removed during recycling, and that recycling processes pass “Quantitative Microbial Risk Assessments” (QMRA). The problem is that these QMRA’s are often based on estimates. This research further developed methods (begun in WaterRA project 3002) to generate real-world measurements and data relevant to firefighters and domestic users because there are concerns that small amounts of recycled non-potable water might be inadvertently ingested. To test this, a harmless chemical, cyanuric acid, was added to safe water, then twenty-six volunteers used it, and a domestic high-pressure sprayer, to clean a full-sized model car for 10 minutes. The volunteers then collected their own urine for the next 24h because if this test-water is ingested, the cyanuric acid can be measured in the urine. From this it was discovered that the volunteers ‘drank’ an average of 0.13mL. This led to the conclusion that the conservative estimates in the AGWR currently protect domestic non-potable recycled water users, but that prolonged and/or high intensity occupational use of high-pressure sprays should be investigated further.