Rainwater Harvesting Systems in Australia

The Australian continent has an extremely variable climate, as a result of the different oceanic currents and atmospheric variation. Australia has regular cycles of droughts and floods resulting in highly variable storage volumes in its major dams. The population in Australia is nearly 23 million (Australian Bureau of Statistics (ABS), 2011) of which the majority lives in the South-East coast of Australia. The largest cities (see Figure 1) are Sydney (4.58 million people.), Melbourne (4.08 million people), Brisbane (1.07 million people) and Canberra (358,600 people) (ABS, 2011). The water supply storage for these cities is located in the nearby mountain ranges and brought to the metropolitan areas through large distribution water pipes. The urban fringe areas, rural locations and the outback have limited reticulated water supply and often rely on capturing roof water, farm dam water and bore water for their water supply. The roof water in these regions provides the principal potable water supply, whilst farm dam and bore water are often used to meet non-potable requirements and for livestock (ABS, 2010). Historically, this has been different in the urban areas where potable and non-potable supply demands are met with a reticulated water supply. A shift has occurred in the Australian Water industry as a result of population growth, the worst drought in living memory (Horstman, 2007) and a desire to become more sustainable. Total Water Cycle Management has gained momentum in Australia and new property developments must consider all aspects of the water cycle, including water supply, waste water treatment, stormwater control and water quality control of all discharges and supplies (Argue, 2004; Argue & Pezzaniti, 2009; Barton & Argue, 2009; Hardy, 2009; Hardy et al., 2003; Wong, 2006b, c; Wong et al., 2008; Wong & Brown, 2009). Rainwater tanks are being installed in urban areas, resulting in an increase resilience of the cities to droughts and a reduction of mains water demand. These rainwater tank installations are encouraged in various Development Control Plans (DCPs), through state legislation, such as the NSW Building and Sustainability Index (BASIX Sustainability Unit, 2009), and by providing rebates (Blacktown City Council, 2006; Blue Mountains City Council, 2005; Gardiner & Hardy, 2005; Ku-ring-gai Council, 2005; Penrith City Council, 2010). The reasons for installing a rainwater tank in Australia include reducing mains water costs, helping the environment, irrigating the garden and because it was mandatory when the house was built (ABS, 2010; Blackburn et al., 2010; White, 2010)

Comment on "Toxicological relevance of emerging contaminants for drinking water quality" by M. Schriks, M.B. Heringa, M.M.E. van der Kooi, P. de Voogt and A.P. van Wezel [Water Research 44 (2010) 461-476]

This is the post-print version of the final paper published in Water Research. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2011 Elsevier B.V.No abstract available

Assessing the risks of recycling urban stormwater for potable supply via an aquifer

Urbanisation and the subsequent increase in impervious land use generate increased urban stormwater which can be recycled viamanaged aquifer recharge (MAR) to supplement more traditional surface or ground water supplies. This paper compares the quality of stormwater from two urban catchments in South Australia to assess the risks, in accordance with the Australian Guidelines for Water Recycling, of recycling stormwater via a limestone aquifer for potable water use. In the regional city of Mount Gambier, stormwater MARin a karstic aquifer has been used to supplement the city\u27s drinking water supply for over 100 years. The source water was generally high quality with some instances of turbidity, iron and lead exceeding the Australian Drinking Water Guidelines (ADWG). Effort wasmade to constrain the estimate of minimum residence time within the karstic aquifer to at least two years for evaluation of the potential for passive treatment of trace organic chemicals in this system. In the second example, a purpose built MAR site in Parafield, a northern suburb of Adelaide, has been designed and operated asa full scale trial to determine if wetland treated urban stormwater can be recovered at a standard which meets the ADWG. Based on the analysis undertaken, the source water was generally of high quality with occasional instances of levels of iron and microbial indicators in excess of the ADWG. After a mean residence time in the aquifer of 240 days, recovered water qualitymet the ADWGwith the exception of iron. However, given the uncertainty in pathogen concentrations in the treated stormwater post-recovery from the aquifer, disinfection and aeration for iron removal would be necessary to ensure that the ADWG were met if the water was to be utilised for potable water supply

Water Reuse in Europe - Relevant guidelines, needs for and barriers to innovation

An EU regulatory instrument for water reuse is planned to be developed by 2015, in order to find innovative solutions to the challenges of ensuring water supply for urban, industrial and agriculture use. Despite the water reuse applications already developed in many countries, a number of barriers still prevent the widespread implementation of water reuse around Europe and on a global scale. These barriers will have to be overcome. This JRC Science and Policy Report analyses the technical, environmental and socioeconomic challenges to the option of water reuse as a means of ensuring sufficient supply to meet the growing needs of society. It presents and compares the most relevant national and international guidelines on water reuse, evaluates existing water reuse standards in EU Member States, presents a risk-based management approach for wastewater reuse, and identifies the areas that require technological and regulatory innovation as well as the barriers to be overcome.JRC.H.1-Water Resource

Quality assessment and primary uses of harvested rainwater in Kleinmond, South Africa

water security, reaching the Millennium Development Goals (MDGs) and sustaining water resources. The microbial and chemical quality of RWH samples collected from tanks in a sustainable housing development in Kleinmond, South Africa, were monitored. Results indicated that the tank water quality was within all the chemical standards (cations and anions) analysed for potable water. However, the counts of the indicator organisms, for example, total coliforms and Escherichia coli, exceeded the guidelines stipulated by the Department of Water Affairs and Forestry (1996). The microbial analysis results thus indicate that the tank water was not fit for potable use without treatment. A social research project was then conducted to describe, amongst others, the condition of the tank and the users’ knowledge of the RWH system. In addition, demographic data, viz., gender, household size and employment status, etc., were gathered in order to provide a socio-economic background description of the study population. Data were gathered by means of face-to-face interviews with 68 respondents. Generally, RWH was used for washing clothes and for cleaning inside and outside the houses. This study noted that without acceptance and necessary training to maintain and use the tank optimally, it is possible that social development projects, such as the one in Kleinmond, will not be sustainable.Keywords: domestic rainwater harvesting; microbial and chemical quality; social perception; acceptanc

The influence of context and perception when designing out risks associated with non-potable urban water reuse

© 2018, © 2018 Informa UK Limited, trading as Taylor & Francis Group. Perceptions and cognitive bias in relation to reuse water can influence the responses to risk and reward. Much has been written on community perspectives and risk perceptions with regard to recycled water for non-potable use. This paper is distinct in that it focuses on the scheme proponents and those involved in designing and delivering schemes. An analysis of five case studies in Australia across a range of diverse settings revealed that the levels of treatment for various end-uses were in excess of the Australian Guidelines for Water Recycling. The evidence shows that the water industry has a fairly narrow view when identifying risks, and has an insurance type response to mitigating the risk. The overarching drivers for this are either the mitigation of the perceived risk associated with using reuse water, or the lack of an adaptive response to changes in the circumstances

A whole of water approach for the city of Sydney

Urban water managers and policy makers are struggling with the challenge of transitioning to an approach that considers a whole of urban water approach, where water planning and the urban form are considered in an integrated manner. The recent drive for liveable cities, where water is used to enhance the urban landscape through reuse and stormwater management, has seen a shift in focus. This has brought a number of challenges to bear on institutions charged with water planning and management at strategic, tactical and operational levels. Five central challenges have emerged from the research undertaken by ISF, viz.: a) Legislations and regulations that are prescriptive, overlapping and inconsistent, b) Economic and financial systems that are restrictive and traditional, c) Planning that is uncoordinated and non-collaborative, d) Organisational and professional cultures that are siloed and inflexible, e) Citizens engagement that is uncoordinated, technical and uninspiring. Drawing on the approach adopted by the City of Sydney, the paper will illustrate how a number of these challenges were overcome by local council in their attempt to achieve liveability goals, make the city more resilient to climate change, and reduce pollution levels in the water ways and harbour. The City undertook a consultative process to develop a decentralised water master plan that would both drive and guide future recycling, stormwater management, and pollution control initiatives. Six transferrable lessons and enabling actions were identified that will have relevance to other cities and urban planners aiming to achieve a whole water approach and liveable cities

Validation of large-volume batch solar reactors for the treatment of rainwater in field trials in sub-Saharan Africa

The efficiency of two large-volume batch solar reactors [Prototype I (140 L) and II (88 L)] in treating rainwater on-site in a local informal settlement and farming community was assessed. Untreated [Tank 1 and Tank 2-(First-flush)] and treated (Prototype I and II) tank water samples were routinely collected from each site and all the measured physico-chemical parameters (e.g. pH and turbidity, amongst others), anions (e.g. sulphate and chloride, amongst others) and cations (e.g. iron and lead, amongst others) were within national and international drinking water guidelines limits. Culture-based analysis indicated that Escherichia coli, total and faecal coliforms, enterococci and heterotrophic bacteria counts exceeded drinking water guideline limits in 61%, 100%, 45%, 24% and 100% of the untreated tank water samples collected from both sites. However, an 8 hour solar exposure treatment for both solar reactors was sufficient to reduce these indicator organisms to within national and international drinking water standards, with the exception of the heterotrophic bacteria which exceeded the drinking water standard limit in 43% of the samples treated with the Prototype I reactor (1 log reduction). Molecular viability analysis subsequently indicated that mean overall reductions of 75% and 74% were obtained for the analysed indicator organisms (E. coli and enterococci spp.) and opportunistic pathogens (Klebsiella spp., Legionella spp., Pseudomonas spp., Salmonella spp. and Cryptosporidium spp. oocysts) in the Prototype I and II solar reactors, respectively. The large-volume batch solar reactor prototypes could thus effectively provide four (88 L Prototype II) to seven (144 L Prototype I) people on a daily basis with the basic water requirement for human activities (20 L). Additionally, a generic Water Safety Plan was developed to aid practitioners in identifying risks and implement remedial actions in this type of installation in order to ensure the safety of the treated water

Consumer perception of water quality during an off-flavor event in Fortaleza-Brazil.

During a taste and odor episode (2-methylisoborneol) in a reservoir that supplies the Fortaleza Metropolitan Region, Brazil, two surveys were conducted to determine tap water usage behavior as well as the sensory sensitivity towards off-flavors of participants with the same level of education. Most volunteers did not consume tap water, mainly due to safety concerns (57%) and disagreeable organoleptics (21%). The majority of those who did use tap water (73%) did so because of economic reasons and the remainder because of the use of point-of-use water filtration systems, which rendered the water safer in their perception. The Human Development Index (HDI), as a measure of income, did not influence the rate of rejection. Volunteers from low and medium HDI neighborhoods were as likely to reject tap water as those from high HDI neighborhoods. Chlorine flavor and earthy flavor were the most perceived off-flavors. Water containing moderate amounts of off-flavor compounds (dilution 1:2 tap/bottled water) was considered ‘acceptable’ by volunteers while water containing low concentrations (dilution 1:5 tap/bottled water) was considered ‘good’