Description:
Abstract Water resource development has played a crucial role in the Grampians, Wimmera and Mallee regions of Australia, with the main source of surface water located in several reservoirs in the Grampians mountain ranges. Historically, water was delivered by gravity through a vast 19 500 km earthen channel system from the reservoirs to the townships and farms. As a result of the severe and protracted drought experienced in the region over the past 13 years and the projected drying climate, there have been fundamental changes made to the management of water in order to better cope with water scarcity. The primary strategic effort to sustainably manage water resources was by removing the unsustainable transport of water via the open channels which resulted in very high losses through seepage and evaporation. This inefficient system has been replaced by a pressurised pipeline, the largest geographical water infrastructure project of its type in Australia, spreading across an area of approximately 20 000 km2. To manage the change in water balance as a result of the pipeline and drying climate, the regions water corporations and environmental agencies have designed a scheme for water allocations intended to sustain local communities, allow for regional development and improve environmental conditions. This paper describes the unique pipeline system recently completed, provides a brief summary of water sharing arrangements and introduces the research program currently underway to optimise the performance of the pipeline system.
Description:
Abstract Water resource development has played a crucial role in the Grampians, Wimmera and Mallee regions of Australia, with the main source of surface water located in several reservoirs in the Grampians mountain ranges. Historically, water was delivered by gravity through a vast 19 500 km earthen channel system from the reservoirs to the townships and farms. As a result of the severe and protracted drought experienced in the region over the past 13 years and the projected drying climate, there have been fundamental changes made to the management of water in order to better cope with water scarcity. The primary strategic effort to sustainably manage water resources was by removing the unsustainable transport of water via the open channels which resulted in very high losses through seepage and evaporation. This inefficient system has been replaced by a pressurised pipeline, the largest geographical water infrastructure project of its type in Australia, spreading across an area of approximately 20 000 km2. To manage the change in water balance as a result of the pipeline and drying climate, the regions water corporations and environmental agencies have designed a scheme for water allocations intended to sustain local communities, allow for regional development and improve environmental conditions. This paper describes the unique pipeline system recently completed, provides a brief summary of water sharing arrangements and introduces the research program currently underway to optimise the performance of the pipeline system.
Description:
Australian water organisations currently rank within the nine sectors identified by the Federal Government under the category of Critical Infrastructure (CI), as designated by the Attorney General's Department. As such, water from a CI protection perspective is considered to be a vulnerable target for terrorism. Major global terrorist incidents such as the attack in New York in 2001 coupled with the media interest and associated amplification have highlighted the need for organisations to protect water infrastructure from future attacks. The Victorian Government is leading the path to terrorism risk reduction of CI by the introduction of an Act of Parliament Terrorism (Community Protection) Act 2003, assuring that risk mitigation is in place across the state. One requirement under this Act is to annually practice plans and procedures in the form of scripted Crisis Simulation Exercises (CSE). These CSEs are to ensure that water organisations are more resilient to meet the challenge and maintain business continuity during any future terrorist incident. This includes the interactions and timings of available resources, logistics with appropriate personnel as required and to the appropriate level indicated in the plans. These CSEs can incorporate live actions, testing equipment and personnel within all organisational levels. It is considered that CI organisations which adopt these strategies enhance business survival and continuity, producing a resilient entity prepared for and resistant to penetration by an organised terrorist group or radical cell. This paper provides an overview of a simulation framework to ensure preparedness suitable for mitigation of risk of terrorism in relation to the Australian water industry.
Description:
Terrorism has progressed to a global phenomenon as a terrorist attack has an immediate effect on society not only in the targeted area, but also across the rest of the world. Acts of terrorism are extremely difficult to predict or provide early warning in most cases. In consideration of Australia, which is to a certain extent insulated from the rest of the world by virtue of the sea barrier, there is a history of terrorist incidents reported back to the 1970s. Since the attack on New York in September 2001, the level of terrorism alert to Australia has increased significantly with a current 'Medium' national level of threat. Critical Infrastructure (CI), which is considered essential for contemporary social human existence, has been impacted by multiple and variable external threats in modern times. The destruction at Chernobyl in 1986 and more recent events such as the terrorist incidents at Madrid in 2004, London in 2005, Moscow in 2011 and the tsunami in Japan in 2011 indicate the vulnerability of this infrastructure. Such events translate to threats from both natural disasters referred to as all hazard origin and human interventions such as terrorism. Subsequently, some private and government organisations of CI now regularly rehearse and simulate models of both terrorist incidents and all hazard events as a proactive protection strategy and business continuity process. These models are implemented in a form of scripted Crisis Simulation Exercises (CSE) which simulate a crisis within an organisation in order to strengthen an organisation's ability to manage crisis situations. CI organisations which adopt these strategies are able to mitigate impact of these crises and therefore, are considered to reflect a more resilient organisation to the effects of external impact. CSEs test plans, procedures, equipment and personnel to industry standards required. Within the spectrum of counter-terrorism in particular, the CSEs are becoming more sophisticated and reflective of reality with incorporation of live actions to ensure credibility and reality. The simulated scenario may include a variety of attack methodologies such as biological, chemical, cyber and conventional bombs/blasts and bullets to maintain exercise standards with continuously developing technology of terrorist attacks. This paper defines the topic of terrorism with the profile of terrorists, and examines the terrorism concept and environment both in Australia and internationally including future considerations. It also provides an overview of the simulated framework for mitigation of crisis associated with CI protection with an Australian perspective, suitable for CI protection worldwide. Additionally, this paper examines the concept of terrorism simulation, illustrating a strong case for future simulation progression with some innovative ideas and futuristic predictions as to where terrorist simulations may advance to across the future.
Description:
Water distribution systems have a very long and rich history dating back to the third millennium B.C. Advances in water supply and distribution were followed in parallel by discoveries and inventions in other related fields. Therefore, it is the aim of this paper to review both the history of water distribution systems and those related fields in order to present a coherent summary of the complex multi-stranded discipline of water engineering. Related fields reviewed in this paper include devices for raising water and water pumps, water quality and water treatment, hydraulics, network analysis, and optimisation of water distribution systems. The review is brief and concise and allows the reader to quickly gain an understanding of the history and advancements of water distribution systems and analysis. Furthermore, the paper gives details of other existing publications where more information can be found.
Description:
Impact of water quality conditions in sources on the optimal operation of a regional multiquality water distribution system is analysed. Three operational objectives are concurrently minimised, being pump energy costs, turbidity and salinity deviations at customer nodes. The optimisation problem is solved using GANetXL (NSGA-II) linked with EPANet. The example network incorporates scenarios with different water quality in sources. It was discovered that two types of tradeoffs, competing and non-competing, exist between the objectives and that the type of tradeoff is not unique between a particular pair of objectives across scenarios. The findings may be used for system operational planning.
Description:
Impact of water quality conditions in sources on the optimal operation of a regional multiquality water distribution system is analysed. Three operational objectives are concurrently minimised, being pump energy costs, turbidity and salinity deviations at customer nodes. The optimisation problem is solved using GANetXL (NSGA-II) linked with EPANet. The example network incorporates scenarios with different water quality in sources. It was discovered that two types of tradeoffs, competing and non-competing, exist between the objectives and that the type of tradeoff is not unique between a particular pair of objectives across scenarios. The findings may be used for system operational planning.
Description:
Hydraulic simulation models have become a valuable tool to manage water distribution networks commencing from their initial design through their operation, assessment of the level of service to customers, system performance improvement, analysis of planning alternatives, to system optimisation. The development of hydraulic models can be a time consuming task with complex and large scale water distribution networks being particularly challenging. The Wimmera Mallee Pipeline (WMP) in Western Victoria, Australia is a recently constructed and unique regional scale water distribution system which consists of over 8,800 km of pressurised pipelines spreading across an area of approximately 20,000 km 2. Currently, the WMP provides water to 34 townships, rural farms and other water users across the Wimmera Mallee region with an annual design capacity of 31.6 mil. m 3. The WMP sources its water from multiple reservoirs in the Grampians mountain ranges in the south and the River Murray in the north. Grampians Wimmera Mallee Water (GWMWater) is the local water organisation responsible for managing the WMP. GWMWater is currently initiating the development of a water market to generate and support growth, and to ensure that water is available for the highest value social, economic or environmental use. The hydraulic models discussed in this paper will assure that informed decisions are made by GWMWater regarding the capacity to deliver water through the pipeline system, and therefore the extent of trade by customers. The philosophy for development of the WMP hydraulic models was to replicate the real system as credibly as possible into the level of required accuracy for decision making, yet enable simple model operation, maintenance and update. The network is modelled to the individual customer level in order to accommodate small diameter pipes. Modelling at this level simplifies the future model maintenance and updates, and also ensures the compatibility with other GWMWater's systems such as Geographic Information System (GIS) and the customer database. A major part of the model development consisted of data preparation. This was undertaken by using "as constructed" GIS asset data captured during the WMP construction and entered into a GIS database (ArcGIS by ESRI). Due to the scale of the system and associated amounts of data, it was essential to develop sophisticated data transformation and validation procedures to simplify the model build which thereby minimised manual data entry and potential sources of errors. This paper focuses on the methodologies and techniques used in data preparation for hydraulic models and development of hydraulic models. An example is also provided of how the models will be used as a decision support tool in water supply and allocation planning.
Description:
The operation of a water distribution system is a complex task which involves scheduling of pumps, regulating water levels of storages, and providing satisfactory water quality to customers at required flow and pressure. Pump scheduling is one of the most important tasks of the operation of a water distribution system as it represents the major part of its operating costs. In this paper, a novel approach for modeling of pump scheduling to minimize energy consumption by pumps is introduced which uses pump's start/end run times as continuous variables. This is different from other approaches where binary integer variables for each hour are typically used which is considered very impractical from an operational perspective. The problem is formulated as a nonlinear programming problem and a new algorithm is developed for its solution. This algorithm is based on the combination of the grid search with the Hooke-Jeeves pattern search method. The performance of the algorithm is evaluated using literature test problems applying the hydraulic simulation model EPANet.
Description:
This paper presents an extensive analysis of the sensitivity of multi-objective algorithm parameters and objective function scaling tested on a large number of parameter setting combinations for a water distribution system optimisation problem. The optimisation model comprises two operational objectives minimised concurrently, the pump energy costs and deviations of constituent concentrations as a water quality measure. This optimisation model is applied to a regional nondrinking water distribution system, and solved using the optimisation software GANetXL incorporating the NSGA-II linked with the network analysis software EPANet. The sensitivity analysis employs a set of performance metrics, which were designed to capture the overall quality of the computed Pareto fronts. The performance and sensitivity of NSGA-II parameters using those metrics is evaluated. The results demonstrate that NSGA-II is sensitive to different parameter settings, and unlike in the single-objective problems, a range of parameter setting combinations appears to be required to reach a Pareto front of optimal solutions. Additionally, inadequately scaled objective functions cause the NSGA-II bias towards the second objective. Lastly, the methodology for performance and sensitivity analysis may be used for calibration of algorithm parameters.
Description:
The impact of water quality conditions in source reservoirs on the optimal operation of a regional multiquality water-distribution system is analyzed. The optimization model concurrently minimizes three operational objectives being pump energy costs, turbidity, and salinity deviations at customer demand nodes from allowed values. The optimization problem is solved using the optimization tool GANetXL incorporating the NSGA-II, linked with the network analysis software EPANet. The example network adapted from the literature captures some of the unique features of the Wimmera Mallee Pipeline in Australia. Six scenarios representing different water quality conditions in source reservoirs are analyzed. It was discovered that two types of trade-offs, competing and noncompeting, exist between the objectives and that the type of trade-off is not unique between a particular pair of objectives for all scenarios. These and other findings may be of particular use to system operators in their long-term operational planning and decision making. (C) 2015 American Society of Civil Engineers.
Description:
This paper explores the trade-offs between water quality and pumping costs objectives in optimization of operation of regional multiquality water distribution systems. The optimization model is designed to concurrently minimize each objective, where water quality is represented by the deviations of constituent concentrations from required values and pumping costs are represented by energy consumed by the pumps. The optimization problem is solved using an optimization software, incorporating the nondominated sorting genetic algorithm II (NSGA-II), linked with network analysis software. Two typical but purposefully different example networks are used. First, a network with multiple water sources of different qualities and second, a network with one water source only, which was converted to represent a regional nondrinking water distribution system. The trade-offs between water quality and pumping costs are explored using a total of 14 scenarios reflecting different water quality configurations of these networks. Those scenarios, into which time variability was introduced for both source water quality and customer water quality requirements, were systematically developed to represent real-life situations that could be found in practice. The results indicate that for the majority of the scenarios, there is a trade-off with a competing nature between water quality and pumping costs objectives. Additionally, it was discovered that multiobjective optimization problems with water quality (i.e., concentration deviations) and pumping costs objectives could be reduced in certain instances into a single-objective problem of minimizing pumping costs. In fact, a regional water distribution system in which water quality is represented by a single conservative constituent can produce either a trade-off or single-objective solution between those two objectives, and this outcome is dependent on both the water quality configuration of the system and system operational flexibility. Last, some particular conclusions are drawn for both a water distribution system with multiple water sources and a water distribution system with a single water source, which suggest how changes in source water qualities or customer water quality requirements may impact system operation. It is, therefore, demonstrated that water utilities which operate regional multiquality nondrinking water distribution systems could benefit from the exploration of trade-offs between water quality and pumping costs for the purpose of operational planning.
Description:
Pumping cost constitutes the main part of the overall operating cost of water distribution systems. There are different optimization formulations of the pumping cost minimization problem including those with application of continuous and integer programming approaches. To date mainly various metaheuristics have been applied to solve this problem. However, the comprehensive comparison of those metaheuristics has not been done. Such a comparison is important to identify strengths and weaknesses of different algorithms which reflects on their performance. In this paper, we present a methodology for comparative analysis of widely used metaheuristics for solving the pumping cost minimization problem. This methodology includes the following comparison criteria: (a) the "optimal solution" obtained; (b) the efficiency; and (c) robustness. Algorithms applied are: particle swarm optimization, artificial bee colony and firefly algorithms. These algorithms were applied to one test problem available in the literature. The results obtained demonstrate that the artificial bee colony is the most robust and the firefly is the most efficient and accurate algorithm for this test problem. Funding :ARC
Description:
The operation of regional multiquality water distribution systems (WDSs) is a complex task involving multiple objectives in order to meet customer water quantity and quality requirements. These objectives, often conflicting, include scheduling of pumps to minimise pumping costs and mixing different quality waters from sources to ensure adequate quality water for customers. Evolutionary algorithms have been successfully applied to optimise operation of regional WDSs. Although a considerable reduction in pumping costs was demonstrated in past studies, other legitimate objectives, for example water quality, were not considered on an equal basis as they were included as a constraint. This single-objective approach precludes the tradeoffs between the objectives being obtained, so any insight on how to operate such a system cannot be provided should pumping costs and water quality be considered on equal basis. A multi-objective approach is applied in this thesis to optimise operation of regional multiquality WDSs considering pumping costs and water quality as legitimate objectives. Two optimisation models with increasing complexity are proposed. The first model considers two objectives, the pumping costs and a general water quality objective. The second model includes three objectives, the pumping costs and two water quality objectives for turbidity and salinity. The optimisation models are applied to three example networks from the literature using numerous scenarios and water quality data from the Wimmera Mallee Pipeline, Australia. A methodology is proposed to find the optimal solution for the multi‐objective optimisation of the WDS, which links a network simulator with a multi-objective genetic algorithm. Prior to optimisation, the performance of algorithm parameters is evaluated and their sensitivity analysed, for which a new methodology is developed. The following results were obtained. For the two-objective optimisation problem, there is a tradeoff with a competing nature between pumping costs and water quality. It means that reduction in pumping costs cannot be achieved without deterioration of water quality delivered to customers and vice versa. For the three-objective optimisation problem, interestingly, there is not a unique type of tradeoff (either competing or non-competing) between a particular pair of objectives. It is dependent on network hydraulics in combination with water quality at sources and customer water quality requirements. General principles behind the tradeoffs are formulated based on new categorisation of sources, so called consistent/inconsistent water quality (CWQ/IWQ) sources, in relation to customer water quality requirements. A practical approach for system operational strategy is developed for the purpose of long-term operational planning. It enables an operator to schedule supply from multiple sources with minimum pumping costs and customer water quality requirements being satisfied as much as possible, for all predicted water quality scenarios in the system.
Description:
The operation of regional multiquality water distribution systems (WDSs) is a complex task involving multiple objectives in order to meet customer water quantity and quality requirements. These objectives, often conflicting, include scheduling of pumps to minimise pumping costs and mixing different quality waters from sources to ensure adequate quality water for customers. Evolutionary algorithms have been successfully applied to optimise operation of regional WDSs. Although a considerable reduction in pumping costs was demonstrated in past studies, other legitimate objectives, for example water quality, were not considered on an equal basis as they were included as a constraint. This single-objective approach precludes the tradeoffs between the objectives being obtained, so any insight on how to operate such a system cannot be provided should pumping costs and water quality be considered on equal basis. A multi-objective approach is applied in this thesis to optimise operation of regional multiquality WDSs considering pumping costs and water quality as legitimate objectives. Two optimisation models with increasing complexity are proposed. The first model considers two objectives, the pumping costs and a general water quality objective. The second model includes three objectives, the pumping costs and two water quality objectives for turbidity and salinity. The optimisation models are applied to three example networks from the literature using numerous scenarios and water quality data from the Wimmera Mallee Pipeline, Australia. A methodology is proposed to find the optimal solution for the multi‐objective optimisation of the WDS, which links a network simulator with a multi-objective genetic algorithm. Prior to optimisation, the performance of algorithm parameters is evaluated and their sensitivity analysed, for which a new methodology is developed. The following results were obtained. For the two-objective optimisation problem, there is a tradeoff with a competing nature between pumping costs and water quality. It means that reduction in pumping costs cannot be achieved without deterioration of water quality delivered to customers and vice versa. For the three-objective optimisation problem, interestingly, there is not a unique type of tradeoff (either competing or non-competing) between a particular pair of objectives. It is dependent on network hydraulics in combination with water quality at sources and customer water quality requirements. General principles behind the tradeoffs are formulated based on new categorisation of sources, so called consistent/inconsistent water quality (CWQ/IWQ) sources, in relation to customer water quality requirements. A practical approach for system operational strategy is developed for the purpose of long-term operational planning. It enables an operator to schedule supply from multiple sources with minimum pumping costs and customer water quality requirements being satisfied as much as possible, for all predicted water quality scenarios in the system.
Description:
The operation of a water distribution system is a complex task which involves scheduling of pumps, regulating water levels of storages, and providing satisfactory water quality to customers at required flow and pressure. Pump scheduling is one of the most important tasks of the operation of a water distribution system as it represents the major part of its operating costs. In this paper, a novel approach for modeling of pump scheduling to minimize energy consumption by pumps is introduced which uses pump's start/end run times. We separate two types of pumps, one is operated based on the water level in a storage and another one is operated based on downstream pressure. For the first type of pumps both the explicit and implicit pump scheduling can be used, whereas the second type pumps can be optimized only using implicit pump scheduling. The problem is formulated as an optimization problem and an algorithm is developed for its solution. The performance of the algorithm is evaluated using a literature test problem applying the hydraulic simulation model EPANet.