Water Journal : Water Journal April 2013
WATER APRIL 2013 64 Feature Article ADOPTION PATHWAYS The Adoption Pathways program is aimed at delivering a suite of capacity building projects and socio-technical modelling tools that will provide a focus for participants and stakeholders at a national regional and community level to interact, experiment, and learn from each other. This in turn will: improve community engagement; enrich educational and training programs at the professional and sub-professional levels; and support the development of robust science-policy partnerships. Details of the projects within these programs can be viewed on the CRC-WSC website: www.watersensitivecities.org.au. ENVISIONING A FUTURE WATER-SENSITIVE CITY Our cities and towns have always been the platform of 'social-technical experiments' and the intersection of competing and complementary objectives. It is within these 'melting pots' that the practice of urban planning and design integrates the socio-technical strategies and solutions to emerging and expanding urban water management objectives. The operational principles underpinning water-sensitive cities were described by Wong and Brown (2009) as consisting of: (i) Cities as Water Supply Catchments -- meaning access to water through a diversity of sources at a diversity of supply scales; (ii) Cities Providing Ecosystem Services -- meaning the built environment functions to supplement and support the function of the natural environment; and (iii) Cities Comprising Water Sensitive Communities -- meaning socio-political capital for sustainability exists and citizens' decision-making and behaviour are water-sensitive. CITIES AS WATER SUPPLY CATCHMENTS It is envisaged that future water-sensitive cities would secure their water supply through investment in a diversity of water sources underpinned by a range of centralised and decentralised infrastructure providing cities with the exibility to access a 'portfolio' of water sources at optimal value and with least impact on rural and environmental water needs (PMSEIC, 2007). Stormwater harvesting is one of the most obvious examples of how cities can start utilising runoff generated from their own catchments, and therefore move towards becoming more self-reliant and resilient. Stormwater volumes discharged each year from Australian cities are substantial; while Brisbane and Sydney generate far more runoff than these cities are using, Melbourne discharges a comparable volume of runoff to what it uses. Major advancements have been made in the eld of stormwater harvesting in the last decade alone, however the research and practice is far behind management of any other water sources. Stormwater has a highly intermittent nature, while its quality is variable and dif cult to predict. However, stormwater is still of similar and often better quality than conventionally treated sewage (Wong et al., 2012). Our understanding of pathogen and chemical risks in stormwater remains limited, and therefore conservative estimates of pathogen and toxicant End use as per current Australian guidelines Municipal use with restricted access (RAa) and drip irrigation (RAb) Municipal use with unrestricted access (UA) Dual reticulation with indoor and outdoor use (NP) Drinking water **** Pre-treatment Screens Before storage GPTs Preliminary Oil and sediment separators Swales* Tanks** Sediment basins Ponds and lakes** Secondary In ltration systems* Wetlands** Bio lters*,** Stormwater lters Advanced*** Sand lters After storage Aquifers** Suitable drinking water technologies (e.g. micro ltration, reverse osmosis, and advanced oxidation) * Could also be used for collection ** Could also be used for storage *** Alternative/ additional drinking water technologies should be adopted where speci c issues are present (e.g. colour, metals, odour, etc.) **** Stormwater should currently only be used for indirect potable use, as far more research is needed prior to direct potable use Water quality level achieved when disinfection is employed (e.g., chlorination) Currently requires disinfection but this requirement may be removed in the near future with the advancement of WSUD technologies.
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