Water Journal : Water Journal August 2013
39 Ozwater Report reconstruction of a signi cant water infrastructure facility following severe earthquake damage. According to Robert Meek, the earthquakes highlighted the need to develop resilient infrastructure and robust management plans. Transforming spatial risk-based earthquake observations and mitigation measures into components of the asset lifecycle is bringing further clarity to the signi cance and staff responsibilities of each item. Mitigation measures, such as preparing water tanker ttings, fostering relationships, eld operator measurement of network pressures and good management of data, from the start of an earthquake event are invaluable. In the long term, maintaining business continuity plans and holding realistic training exercises are vital. Gary Hallsworth said that disaster resilience for a small water utility requires timely resumption of essential business activities. Aqwest, a small water utility on the south-western coast of Western Australia, used recommended tools, training and advice to nd and address vulnerabilities associated with dependence on a single business centre, lack of standby power, and management of critical spares. Under the quirky title, 'Resilience, The New Black', Warren Adams made the point that resilience is increasingly becoming a dominant objective in the planning, design, operation and maintenance of public infrastructure -- both for major or extreme events, and more commonly, day-to-day incidents. Simon Webber presented details of the successful design, proving and regulatory approval of unique in-line sh egg ltration screens that prevent the transfer of alien sh eggs from the Murrumbidgee River into the Googong Reservoir. Robust design, a prudent approach to fabrication and testing, including construction and testing of a full-sized prototype, enabled the proponents to effectively manage a major environmental risk to the project. The merging of Seqwater with LinkWater in SE Queensland led to the integration of a Drinking Water Quality Management Plan and associated systems for the new organisation. The focus will be to provide a safe, secure and reliable water supply and to protect public safety through established, holistic water quality management. Wade Manuel laid out the process by which certi cation under ASNS ISO22000 was achieved, providing assurance for stakeholders that water quality and business processes will be continuously improved. Elsinore Mann described a computerised, high-speed optimisation process that quickly establishes a short-list of the most cost-effective water system designs that also provide a high degree of operational redundancy and, hence, robustness. Delegates learned from Karl Mallon that the AdaptWaterTM tool can be used to assist in managing the complex nature of climate change related decision-making for asset management, including temporal, spatial, technical, nancial, social and probabilistic information management. The tool has been developed to deliver a exible risk management investment/adaptation approach acceptable to stakeholders ( nancial controllers, economic regulators and environmental authorities) to enable effective climate change adaptation. Iterative use allows the discovery of optimum adaptation solutions. Moving from planning to real-time operations, Martijn Bakker spoke about the Gruszczyn Water Treatment Plant, which supplies part of the city of Poznan in Poland. The conventional production control and pressure controls of the facility were replaced by advanced software called OPIR. Production ows and pressures were compared, under normal and advanced control, revealing that advanced control led to 83% less variation in production ow and 29% lower pressure of the clear water pumps. The lower pressure resulted in 20% less background leakage and the overall energy costs of the system were reduced by 11.5%. Stephen Jewell related the story of devastation caused by oods in Victoria in January 2011. The poor water quality associated with the oods in the Grampians has persisted, after two years, being worse than at any time before. In a nancial regulatory climate that emphasised frugality, the water business had to be very ingenious to nd solutions that were both affordable and effective. Turning from water to pipes, Relene Wei and colleagues in WA had found the failure of cast iron pipes could be attributed to several factors, one of the most important being graphitisation of sections of pipe. The worst offenders were pipes laid in the 1940s and 1950s. Environmental factors that also contributed to failures included soil aggressiveness, depth to water table and operating pressure. A priority list for replacing pipes on rational criteria was developed. Peter Kinley demonstrated a methodology for understanding and benchmarking the performance of water industry assets. A severity and extent scoring system is used to translate sub- component condition observations into reliability scores against a variety of failure modes, namely: structural integrity; water quality; and health and safety performance. An innovative iPad and Cloud storage data management system provides an ef cient and common framework complaint approach, which is able to quanti ably prioritise maintenance and investment programs of work. A key asset class in water systems is ow meters, and Karl Blackhall revealed an innovative new algorithm for identifying faulty meters based on age, meter type, location and consumption pattern. This results in a reduction in non-revenue water, adherence to compliance guidelines, and more ef cient meter replacement through targeted prediction of meter non-compliance. The challenge of achieving good waterway condition in a climate of cost minimisation was described by Ashley Lorenz. He suggested that, for wastewater treatment plants in SE Queensland to perform any better than they currently do, service providers need fewer constraints on treatment options. An holistic approach to planning and implementation is needed, so optimal outcomes can be achieved through synergies. Unity Water was able to augment the Maleny STP and save $11m on capital through total water cycle management. To replicate this success, though, requires the regulators to consider works outside the STP as part of a solution. Karen Cox addressed the need to store polyvinyl uoride ultra ltration membranes in a sodium hypochlorite solution when not in use. Low water demand on two membrane plants in Adelaide meant that frequent storage was required. The membranes were thus exposed to high levels of chlorine, potentially shortening their lives. Alternative strategies had to be found to mitigate the chlorine exposure. Turning from treatment to storage, Kah Boon Quek outlined the dif culties of optimising the frequency of reservoir cleaning. A decision tool was required to help decide when to clear sediment that compromises water quality. It was found that, in Perth, groundwater was most prone to lead to a build-up of sediment; followed by untreated water; then a low rate of turnover of the reservoir. The authors noted weaknesses in some of the underlying assumptions, and looked forward to empirical evidence to re ne the tool. Current cleaning cycles are typically in the one-to- ve-year range.
Water Journal June 2013
Water Journal September 2013