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Water Distribution System Management

Water distribution system management

Water distribution system management

Water distribution system management

Please see below for some of our research projects related to water distribution system management.

Current Projects

The aim of this project is to develop a digital twin for water pipe systems to predict performance of the pipe network.

Recent Projects

Application of innovative statistical models to automate process control tools that manage water pipeline infrastructure.

The aqua3S project aims to create strategies and methods that will enable water facilities to easily integrate solutions regarding water safety, through a combination of novel technologies in water safety and the standardisation of existing sensor technologies.

Exposure of citizens to potential disasters has led to vulnerable societies that require risk reduction measures. Drinking water is one of the main risk sources when its safety and security are not ensured.

aqua3S combines novel technologies in water safety and security, aiming to standardize existing sensor technologies complemented by state-of-the-art detection mechanisms. aqua3S can propose innovative solutions to water facilities and responsible authorities in order to detect and tackle water-related crises in a timely manner.

On the one hand, sensor networks are deployed in water supply networks and sources, supported by complex sensors for enhanced detection; on the other hand, sensor measurements are supported by videos from Unmanned Aerial Vehicles (UAVs), satellite images and social media observations from citizens that report low-quality water in their area (e.g. by colorization); introducing this way a bottom-up approach which raises social awareness and, also, promotes interactive knowledge sharing.

The proposed technical solution is designed to offer a very effective detection system, taking into account the cost of the aqua3S platform and target at a very high return-on-investment ratio.

The main strategy for the integration of aqua3S’ solution into the market is designed on the standardization of the proposed technologies and the project’s secure platform.

Visit the aqua3s website for further information.

So far, individual water companies have been able to use open data and Artificial Intelligence to gradually improve their performance in delivering services. Through this initiative, Severn Trent are leading this cross-sector coalition to go much further, piloting an autonomous system to monitor an entire waste catchment. By bringing together extensive testing with emerging technologies, this approach can work through huge amounts of data to provide real-time insights to help water companies reduce the risk of flooding and sewerage pollution in a catchment: delivering benefits for both customers and the environment. 

Through this project, the delivery team will be developing a tried and tested blueprint for how this approach can be scaled across the UK. More broadly, the team hope that this project can be a catalyst for wider use of AI in the water sector, building trust and demonstrating the value of this important technology. 

Led by: Severn Trent Water

Partners: South West Water, Southern Water, Thames Water, Hafren Dyfrdwy Water, Northumbrian Water, Microsoft, Rockwell, British Telecom, Blackburn-Starling, 8power, National Cyber Security Centre, University of Exeter.

Funder: Ofwat Water Breakthrough Challenge

For further information, please visit the Ofwat website

The aim of this fellowship is to develop novel technologies to facilitate the delivery of smart and resilient water systems.

The aim is to develop analytical tools to analyse big data from smart sensors at household and system levels, so as to identify vulnerabilities and inform infrastructure planning, design, operation and management decisions and thus improve resilience.

This project aimed to develop a flexible approach for water system planning and management that takes into account uncertainty and allows decision adjustments to be made as new information, new funds or new opportunities become available.

FIWARE is a smart solution platform, funded by the European Commission (2011-16) as a major flagship PPP, to support SMEs and developers in creating the next generation of internet services, as the main ecosystem for Smart City initiatives for cross-domain data exchange/cooperation and for the NGI initiative. So far little progress has been made on developing specific water-related applications using FIWARE, due to fragmentation of the water sector, restrained by licensed platforms and lagging behind other sectors (e.g. telecommunications) regarding interoperability, standardisation, cross-domain cooperation and data exchange.

Fiware4Water intends to link the water sector to FIWARE by demonstrating its capabilities and the potential of its interoperable and standardised interfaces for both water sector end-users (cities, water utilities, water authorities, citizens and consumers), and solution providers (private utilities, SMEs, developers). Specifically we will demonstrate it is non-intrusive and integrates well with legacy systems. In addition to building modular applications using FIWARE and open API architecture for the real time management of water systems, Fiware4Water also builds upon distributed intelligence and low level analytics (smart meters, advanced water quality sensors) to increase the economic (improved performance) and societal (interaction with the users, con-consensus) efficiency of water systems and social acceptability of digital water, by adopting a 2-Tier approach:

  • Building and demonstrating four Demo Cases as complementary and exemplary paradigms across the water value chain (Tier#1);
  • Promoting an EU and global network of followers, for digital water and FIWARE (cities, municipalities, water authorities, citizens, SMEs, developers) with three complementary Demo Networks (Tier#2).

The scope is to create the Fiware4Water ecosystem, demonstrating its technical, social and business innovative potential at a global level, boosting innovation for water.

Why Fiware4Water?

The prerequisite of Fiware4Water is to lever the barriers of the water digital sector that is facing a low level of maturity in the integration and standardization of ICT solutions, in the business processes of these solutions and relative implementation of legislative framework, as described by the ICT4Water cluster.

The related needs are how to exploit the value of data for the water sector, how to develop and test robust and cyber-secured systems, how to create water-smart solutions and applications how to ensure interoperability and higher information capacity and how to design tailored solutions addressing a real need such as optimisation, prediction, diagnosis, real-time monitoring.

For further information, please visit the Fiware4Water website.

Objectives

With focus on co-development between EU and India ensuring exploitability of its outcomes, LOTUS brings a new ICT solution for India’s water and sanitation challenges in both rural and urban areas.

High-level objectives:

  1. To co-design and co-produce, jointly with EU and Indian partners, an innovative multi-parameters chemical sensor as an advanced solution for water quality monitoring in India. It shall use advanced technologies (carbon nanotubes) capable of monitoring in real time multiple contaminants and adaptable to diversified use cases in India;
  2. To develop a suite of tailor-made software tools, combined into a platform with cloud-based implementation. By integrating LOTUS new sensors to advanced ICT technologies, it shall improve water management according to the specific requirements of LOTUS Use Cases, representative of water challenges in India;
  3. To demonstrate and showcase the LOTUS sensor and software solution in a wide variety of Indian use cases across the whole value chain of water (urban and rural areas, drinking and irrigation water quality, river and groundwater monitoring, treated wastewater quality). Across use cases, the common goal is to improve on water availability and quality by improving on existing infrastructures, thus answering a wide range of socio-economic and technical water challenges in India;
  4. To investigate, co-design and plan the business model and market uptake of the LOTUS solution, with industrial production and further development and production of the sensor in India, ensuring an advanced but affordable, low cost product and solution for monitoring water quality, after the end of the project;
  5. To promote social innovation, by introducing co-creation, co-design and co-development with Universities, Research Centres, SMEs, NGOs, Utilities and local stakeholders, bringing together social sciences and technology experts, as a paradigm of successful EU-India Cooperation in the water sector, with lasting social, technological and business impacts for water quality in India, leading to viable, affordable and (socially) acceptable products and solutions, capacity development, job creation, contribution to wider issues and initiatives and wide outreach activities.

Visit the LOTUS website for further information. 

This fellowship investigates how to develop smart water infrastructure systems using Information and Communication Technologies (ICT) and big data already available in the water industry in response to a changing environment including extreme weather.

There is a critical need to develop new advanced data and visual analytics to unlock the value of large-scale water utility databases for informed real time decision making on a wide variety of different problems including leakage, flooding, water pollution and energy efficiency. This fellowship offers exactly such an opportunity, through close collaboration with Northumbrian Water Ltd, to turn piecemeal techniques into integrated solutions for industry problems, thus is timely for major impact on large investments in water infrastructure in the next 50 years.

This fellowship aims to develop the next generation advanced analytics and tools that enable real time decision making for management and operation of smart water infrastructure systems. This fellowship will promote wider deployment of sensing and measurement technologies and informed, real time decision-making. It will improve operational automation and efficiency under standard design conditions and operational resilience under extreme conditions. This fellowship is particularly important to provide a step change towards a smart water system where the sensors and controllers are linked together for fully automated decision making in response to dynamic environments.

The five-year Fellowship, awarded to Professor David Butler, worth around £1.5 million, will fund a project which aims to develop a new approach to water management in UK cities.

Safe & SuRe will draw from multi-disciplinary collaboration with leading academics inside and outside the field.

The vision of this work is to develop a system for water management which is sustainable and resilient. A comprehensive, quantitative evaluation framework will be developed to test in detail what options or strategies can contribute towards a Safe and SuRe water future, focusing on the challenges of water scarcity, urban flooding and river pollution.

Objectives

  1. To develop, test and refine the Safe & SuRe water vision in the context of British cities
  2. To investigate, specify and develop a quantitative option assessment framework
  3. To evaluate threat mitigation and adaptation options and strategies and explore potentially conflicting goals and key interdependencies
  4. To develop a strategy for implementation incorporating transitioning approaches, preparedness for extremes, water users’ responses and the neglected role of town planning
  5. To engage widely with academic leaders in urban water management and other fields
  6. To collaborate with stakeholders and champion the vision and key findings into practice.

The key focus is on how existing urban water systems can be better used, managed, regulated, planned, operated, rehabilitated, retrofitted and redesigned to cope with the coming ‘perfect storm’.  

David Butler is Professor of Water Engineering at the University of Exeter with some 30 years of experience in the water industry. He jointly leads the Centre for Water Systems, which has around 30 researchers working mainly in the areas of urban water, system optimisation and hydroinformatics. Working with David on the Safe & SuRe project are colleagues Dr Raziyeh Farmani, Dr Guangtao Fu and Dr Sarah Ward.

Find out more about the Safe & SuRe project via our dedicated webpage.

Using real-time monitoring and control solutions, the Smarter Tanks to build a resilient network project will explore how to best monitor drinking water and rainwater storage tanks to understand if more water can be stored when needed most.

The opportunity to implement smart water tank control into existing infrastructure will:

  • build operational resilience and reduce disruption to customers and the environment
  • pave the way for the rest of the water industry to follow suit

A key outcome of the project will be the development of a one-page business model for each smart tank use case, with supporting evidence gathered from workshops, desktop research and pilot installations to help scale the propositions tested. This will lay the groundwork for other companies or providers to adopt the concept if value is identified through successful proof of concept installations.

Led by: Affinity Water

Partners: Aqua Civils Ltd and University of Exeter

Funder: Ofwat Innovation in Water Challenge

For further information, please contact Principle Investigator Dr Peter Melville-Shreeve or visit the Ofwat website

The worldwide use of decision games, or often called Serious Games ('games that do not have entertainment as their primary purpose'), is becoming more popular and allows players/stakeholders to experience situations that are impossible in the real world for reasons of safety, cost, time or their rare occurrence. Examples of Serious Gaming applications include domains as diverse as healthcare, public policy, defence, training and education. In contrast to traditional Game Theory or Operations Research where scenarios or problems are typically well structured, serious gaming can simulate more complex, dynamic, uncertain, socially-coupled scenarios, referred to as "wicked problems" that are prevalent in the real world. 

Water supply and demand, food production and energy provision and consumption are intimately linked physically, socially and economically, forming the Water-Food-Energy Nexus, an interconnected system that is increasingly a cause for concern due to projected demand growth. Strategic decision making for planning and management of infrastructure supporting the Water-Food-Energy the Nexus is an example of such wicked problems. It can, therefore, benefit from leveraging the technical strengths of simulation models and the social strengths of multi-player/stakeholder engagement in a game execution.

The Serious Gaming approach offers potentially transformative capabilities to strategic decision-support tools to provide better management of complex infrastructure systems compared to purely technical simulation or optimisation methods that have difficulty in capturing the socio-technical challenges of complex systems. The Nexus Game will simulate the evolution of the Nexus system with player(s) interfering in a system's dynamics through various choice variables/interventions. This represents a paradigm shift not only from the approaches that focus solely on technical issues, but also a shift from policy and regulatory regimes that concentrate on individual Nexus components separately.

1. Research idea and transformative nature of the project

Understanding water and its interdependencies with food, energy and the environment is vital if water is to be managed effectively and efficiently. There is, however, a lack of tools to support long-term decisions related to water infrastructure in a wider context of the water, food and energy (WFE) Nexus and in long term. This project will contribute to better management of the complex WFE system by investigating a Serious Gaming (SG) approach (‘The Nexus Game’) as the basis for developing more effective and timely infrastructure policy and decisions at various spatial (local, regional and national) and temporal scales.

Water supply and demand, food production and energy provision and consumption are intimately linked physically, socially and economically, forming the WFE Nexus, an interconnected system that is increasingly a cause for concern due to projected demand growth. This complex system relies on large physical networks of interrelated infrastructure components to support modern societies. However, the Nexus is also a collaborative system with significant technical and social complexity. Water (and its associated infrastructure systems for drinking water supply and wastewater disposal, irrigation, flood control, coastal protection, etc) is the critical ingredient in this connected system, and thus forms the focus of this project.

The worldwide use of decision games, or often called Serious Games ('games that do not have entertainment as their primary purpose'), is becoming more popular and allows players/stakeholders to experience situations that are impossible in the real world for reasons of safety, cost, time or their rare occurrence. Examples of SG applications include domains as diverse as healthcare, public policy, defence, training and education. In contrast to traditional Game Theory or Operations Research where scenarios or problems are typically well structured, serious gaming can simulate more complex, dynamic, uncertain, socially-coupled scenarios, referred to as “wicked problems” that are prevalent in the real world. Strategic decision making for planning and management of infrastructure supporting the WFE system is an example of such wicked problems. They can, therefore, benefit from leveraging the technical strengths of technical simulation models and the social strengths of multi-player/stakeholder engagement in a game execution.

The SG approach offers potentially transformative capabilities to strategic decision-support tools to provide better management of complex infrastructure systems compared to purely technical simulation or optimisation methods that have difficulty in capturing the socio-technical challenges of complex systems. The Nexus Game will simulate the evolution of the WFE system with player(s) interfering in a system's dynamics through various choice variables/interventions. This represents a paradigm shift not only from the approaches that focus solely on technical issues, but also a shift from policy and regulatory regimes that concentrate on individual WFE components separately.

2. Proposed approach

To achieve the above project vision, which is ambitious, multidisciplinary and of a highly strategic nature, the following four research areas will be addressed:

  1. Infrastructure components and interactions within the WFE Nexus: A detailed causal loop diagram laying out qualitative causal relationships among WFE system components will be developed first. This will form a basis for a System Dynamics model with multiple interacting feedback loops. An example of which is the link between single farm payments, land management and flooding. The focus will be on the importance of interactions and feedback between socio-technical components, their scale and the level of complexity that is appropriate for capturing the major processes and elements that characterise their behaviour.

  2. A modelling framework to represent structure and behaviour of the Nexus elements: Infrastructure components of the WFE system are realised as large physical networks (e.g., water supply, drainage, energy, transport, etc.), suggesting a graph-theoretic approach for modelling basic structure. This will be implemented through a complexity science approach (e.g., System Dynamics modelling), which enables simulation of non-linear, feedback driven complex dynamic systems.

  3. Software engineering/informatics aspects of game development and execution: To develop the Nexus Game, a logical framework for gaming and an engine will be required. Both the logical framework and engine will be developed to maximise the use of existing open data, such as maps, rainfall and flow data. Furthermore, as the game will have to be engaging and motivating, interface concepts will be borrowed from successful entertainment games, such as SimCity and Minecraft.

  4. A programme of SG exercises with a number of participants: The game will be centered on the unique interplay of the infrastructure and the WFE Nexus in the UK and will consist of a number of roles, which include policy makers or government, residents, farmers, businesses, water utilities and city planners. The game will be used not only to analyse infrastructure policy options under conditions of uncertainty, but also for educational purposes.  Players’ behaviour during the game could be data-mined to improve the decision making process and the social interaction between the parties.

Previously funded projects in the UK and overseas have contributed scientific knowledge and applications in one of the separate WFE Nexus areas, but nothing on the scale that the unconventional approach adopted in this proposal offers has been attempted in the past. Furthermore, this new approach departs from the classical simulation modelling and ‘predictive approaches’ where a model is calibrated, verified and then used for prediction (with or without uncertainty quantification). The approach proposed here involves a complexity science view of modelling where due to interactions of technical and socio-economic components new properties of the system may emerge that could not have been anticipated (e.g.,‘tipping points’, 'bifurcation points', etc). This is a fundamentally different way of approaching uncertainty and risk analysis in socio-technical systems that could pave way to future decisions that will minimise unintended consequences, such as when biofuels impact on water availability and biodiversity or displace food crops.

3. Impacts, outcomes and risk management

The project will focus on UK water infrastructure and water security within the WFE Nexus (i.e., how it could be achieved; possible future scenarios, threats, synergies, uncertainties; what policy approaches can/should be developed and applied, etc). Thus it would directly address a major societal challenge: how should the UK achieve its basic provisioning of WFE in the future, but with a particular focus on water, a strategic question of great importance to any society. Water security is also vital to future UK economic success and environmental integrity as failure to achieve security could have dire consequences for other sectors.

The work is to be completed in two years, ultimately delivering:

  1. A working prototype of a computer-based Nexus Game platform that can be used for playing the game by at least one player to explore the likely consequences of any decision in the long term, with the potential to be extended to multiplayer capability. Three examples of systems at different scales (from micro to macro) will be developed on the platform, including urban scale (e.g., a town/city), catchment scale (e.g., Somerset Levels), and UK scale.
  2. A new logical framework which can be extended to different objectives beyond the Nexus management and for various scales (local, regional and national).
  3. An open-source engine that supports the ongoing development of serious games for environmental management.
  4. A programme of Serious Game exercises/playing to be undertaken with a number of participants.

The key strategic risk stems from the fact that the project is technically ambitious and it is planned to approach the development by tackling simpler enquiries first and involve stakeholders early on in the process to establish the required Nexus Game elements. There is also a risk with the appointment of a PDRA with required expertise and skills across a number of disciplines (engineering, information technology, decision science, etc). Given the industrial demand for engineers/scientists with such skills is  necessary to offer a salary in the range requested. Another type of risk relates to open data availability for the development of games and visualisation of results. Wherever possible, open data sources will be used, e.g., Defra and Env. Agency. There is a technical risk that computing facilities may be too slow to enable realistic gaming and inform decisions. Use of modular development and latest gaming computer technology (e.g., with a high-spec Graphical Processing Unit) will ensure maximum speed of execution. There is also a risk that the system may not provide the required decision support and this will be mitigated by including potential end-users/stakeholders early on in the project.

4. Difference award will make

The use of Serious Gaming in water engineering and management is in very early stages and requires initial research and development to explore the potential of this exciting approach. This project will deliver a fast turnaround and open this new approach to wider audiences of policy makers, water engineers and other scientists involved in water research and management. This project will also deliver impact nationally (policy-based research) and internationally (by highlighting issues associated with the interdependencies between water, food and energy), which is a key goal of the EPSRC strategic plan. Furthermore, national excellence in simulation and modelling for water engineering applications, with significant international academic impact, will be strengthened because this project combines, uniquely, technical and socio-economic considerations into a single, complexity modelling framework taking account of societies having to adapt national infrastructure for environmental (climate) change. The Principal Investigator will use this project to build on interdisciplinary research he has been conducting at the interface of disciplines that place more emphasis on quantitative rigour (e.g., engineering and computer science) and softer disciplines (e.g., socio-economics), which is normally difficult to get funding for.

Past Projects

The network project is half-way through its three year grant period. It has made good progress in developing and maintaining contact between academic groups researching into computer technology for the design and management of underground infrastructure for the water industry, on both the clean and wastewater sides. Contacts with industry have been strengthened with new industrial members joining, and an increased awareness of the needs of industry conveyed to the academic members.

The success of network is evident in the research proposals drawn up between members, both academic and industrial. For further information, visit the ACTUI website.

The original objectives were:

  1. To encourage mutually beneficial collaboration between academic research groups and between academic groups and the water industry.
  2. To encourage collaboration between academic groups on new research proposals.
  3. To encourage active industrial participation in the formulation and execution of future research projects.
  4. To set up web sites for communication and dissemination of research information, opportunities and initiatives, for discussion groups and for industry links.
  5. To encourage member participation in relevant conferences, symposia and seminars.
  6. To achieve sufficient enthusiasm and support for the network for it to become self sustaining after the initial period of funding.


These objectives remain unchanged. However the means of accomplishing them will be reviewed at the next ACTUI meeting.

The AIA project is led by CWS and aims to explore the feasibility of more integrated urban utility service provision as a potential way to improve the sustainability of urban development. This will be achieved by researching issues of scale, integration and delivery to reduce the use of resources, limit emissions, manage innovation and improve the quality of life in the case study of Ashford, Kent, UK.

Early water work includes a detailed analysis of the working of the Ashford Integrated Water Management strategy. The main research areas covered by AIA project concentrate on the following aspects

  • Sustainable development
  • Utility integration: water & energy/carbon
  • Scale issues
  • Decision making and stakeholders
  • Delivery processes
  • Identification of benefits & best practice
  • Case study (Ashford) and stakeholder focus

Download AIA Project Presentations

For more details on any of these three projects, including how you might wish to be involved, please contact: Prof David Butler or Dr Raziyeh Farmani 

Universities involved in Ashford’s Integrated Alternatives

  • University of Exeter Centre for Water Systems
  • Cranfield University
  • Imperial College London - Business School
  • University of Surrey
  • University of Bradford

Operational energy costs make up a substantial proportion of the annual expenses of water supply utilities. It is thus important that the operational control of water distribution systems is optimized to ensure that appropriate levels of service and reliability are met at minimum cost. The operational optimization problem is complicated by a number of factors: vast numbers of possible operational solutions; variations in demands and electricity tariffs through a typical operating cycle; minimum reservoir level requirements; and limitations on the number of pump switches. An additional complication is the non-linear hydraulic behaviour of water distribution systems, which makes computer modelling of these systems computationally expensive. One of the most effective ways of optimizing the operation of water distribution systems is through the application of genetic algorithms (GAs).

The GA methodology is based on the mechanics of natural selection, combining survival of the fittest with randomized information interchange between the members of a 'population' of possible solutions. A number of studies have shown that GAs can be successfully applied to the operational optimization of water distribution systems. One of the greatest drawbacks of GAs is that they require a large number of function evaluations to achieve convergence. Each function evaluation requires a computationally expensive dynamic simulation of the distribution system which, in turn, makes GA runs time-consuming. The objective of this project was to improve the efficiency of GA optimization. This was achieved by improvements in two areas. The first improvement was made in the dynamic modelling of water distribution systems. A new method, called the Explicit Integration method, was developed. In the Explicit Integration method, the system's hydraulic behaviour is linearized, and the reservoir demand described by a general polynomial function. This allows the reservoir dynamic equations to be solved explicitly. The linear hydraulic coefficients are updated by performing snapshot simulations at regular intervals during the run. The number of snapshot simulations is significantly less than those required by the conventional Euler numerical integration method. By reducing the number of snapshot simulations required for a dynamic simulation, the computational effort is reduced, and thus the simulation running time.

The second improvement to the efficiency of GA optimization was made by combining the GA with a local search method, the Hooke & Jeeves pattern search, in a hybrid method. GAs are good at finding the region of the optimal solution in a large solution space, but much less efficient in then finding the optimum point. Local search methods, on the other hand, are efficient in finding a local optimum, but are not able to escape the attraction basin of this point to search the wider solution space. By combining the GA and local search methods, the advantages of both methods are exploited to improve the efficiency of the optimization method. A number of example applications are used to illustrate the workings of the different methods developed in the study. In the final chapter, both the Explicit Integration and the hybrid methods are applied to a large and complex water distribution system in the UK. It was possible to reduce the time required for an operational optimization run substantially from a number of days to approximately one hour.

References

  • Van Zyl, J. (2001) A Methodology for Improved Operational Optimization of Water Distribution Systems, PhD thesis, University of Exeter.
  • Van Zyl, J., D.A. Savic, G.A. Walters (2002) Operational Optimization of Water Distribution Systems Using a Hybrid Genetic Algorithm Method ASCE Journal of Water Resources Planning and Management, (submitted for publication).
  • Van Zyl, J.E., D.A. Savic and G.A. Walters (2000), A Method for Improved Efficiency in the Dynamic Modelling of Hydraulic Networks, Second ISSMO/AIAA Internet Conference on Approximations Fast Reanalysis in Engineering Optimisation, May 25 ? June 2 (proceeding published on CD), p. 10.
  • Atkinson, R.M.A., van Zyl, J.E., G.A. Walters and D.A. Savic, (2000) Genetic Algorithm Optimisation of Level-Controlled Pumping Station Operation, Water Network Modelling for Optimal Design and Management, CWS 2000, Centre for Water Systems, Exeter, UK, pp. 79-90.
  • Van Zyl, J.E., D.A. Savic and G.A. Walters (2001), An Explicit Integration Technique for the Dynamic Modeling of Water Distribution Systems, World Water & Environmental Resources Congress, May 20-24, Orlando, Florida, edited by Phelps, D. and G. Sehlke (proceeding published on CD), p. 10.
  • Van Zyl, J.E., D.A. Savic and G.A. Walters (2001), "A Hybrid Method for Operational Optimization of Water Distribution Systems", in Water Software Systems: Theory and Applications, Vol. 2, Ulanicki, B., Coulbeck, B. and Rance, J.P. (eds.), Research Studies Press, Baldock, Hertfordshire, England, pp. 89-97.
  • Van Zyl, J.E., D.A. Savic and G.A. Walters (2002), Accuracy Issues in Extended Period Modelling of Water Distribution Systems, First Symposium on Environmental and Water Resources Systems Analysis, ASCE, May 19-22, Roanoke, Virginia, Kibler, D.F. (ed.), (proceeding published on CD), p. 10.

Wastewater reuse presents a feasible solution to the growing pressure on Europe's water resources. However, wastewater reuse implementation faces obstacles that include insufficient public acceptance, technical, economic and hygienic risks and further uncertainties caused by a lack of awareness, accepted standards, guidelines and uniform European legislation.

So far, there are no European regulations on water reuse and further development is slowed by lack of standards in water quality, treatment and distribution systems. While guidelines for agricultural water reuse have been defined by the World Health Organisation, and by different states such as the USA and Saudi Arabia, a uniform solution for Europe is lacking. European standards have to take a complex water policy and management framework into account and have to balance the protection of water resources, economic and regional interests and consumer-related safety standards.

The Centre's involvement concentrates on WP8 of the project dealing with optimal total system design, using multi-objective Genetic Algorithms with mathematical modelling tools for different components of the reuse system (piping network, wastewater treatment plants, upgrading, etc).

Working as part of the AQUAREC consortium (www.aquarec.org), the Centre for Water Systems, University of Exeter recently developed decision support software (DSS) for Water Treatment for Reuse and Network Distribution (WTRNet). As the name suggests, the software has been developed that addresses both the treatment and distribution aspects of potential water reuse schemes, considered at a planning level. This article describes in brief the process followed in the development of WTRNet software and provides a description of its key features. A PowerPoint presentation can be found here (4MB).

Reclaimed water projects typically include construction of new treatment or upgrades to a municipality’s treatment systems to clean wastewater to the required quality level, and construction of distribution systems which may include pipelines, pumping and storage facilities for reclaimed water. Therefore, the complexity associated with the planning of water reuse systems is very high, as a very large number of design combinations is possible. Also, one of the requirements of the AQUAREC project was that the spatial relation between wastewater treatment sites and potential reuse locations has to be considered. To aid in the planning of water reuse schemes several DSS have been developed in the past. A comprehensive literature review of DSS in the water reuse area revealed that the majority of water reuse research has been focused on the generation, evaluation and optimisation of treatment, despite the fact that “no single factor is likely to influence the cost of water reclamation more than the conveyance and distribution of the reclaimed water from its source to its point of use” (US EPA Guidelines for Water Reuse, EPA/625/R-04/108, 2004). Several researchers considered the distribution system in their evaluation of reuse schemes, with significant simplifications of treatment processes.

The key objective in the development of WTRNet was to develop a DSS that overcomes the limitations of existing tools, by addressing both the treatment and distribution aspects of water reuse schemes in an integrated manner and with sufficient detail. The software development focused on allowing the user to deal with the following questions:

What processes are needed to produce reclaimed water of adequate quality for a specified influent quantity/quality and end-user requirements?
How is the reclaimed water going to be delivered to end-users (i.e., sizes of distribution system components required)?
Who should receive the reclaimed water (i.e. best selection of customers from the identified potential end-users)?
Click here if you want to download a PowerPoint presentation of the work on development of WTRNet.

In order to conduct evaluations required to answer the above questions in an efficient manner, the simulation component was first developed along with a user-friendly interface. The simulation model includes a default knowledge base stored in the project file, as well as separate computational modules for treatment performance and sizing of the reclaimed water distribution system. The model knowledge base contains the following information: the design and costing information on unit processes, water quality requirements for different types of end uses of reclaimed water, suggestions for treatment trains that could be used for influent quality / end use combinations, rules for combining unit processes, and the design and costing information on the distribution system components. Information on treatment processes has been verified by comparing the software outputs with existing reuse schemes and values for cost and performance of treatment options reported in the literature.

The treatment performance has been developed with functionality to perform the evaluation of user-selected combinations of unit processes in a treatment train. The evaluation of treatment train performance and the display of treatment train evaluation results are carried out as changes to the treatment train are made. Since the evaluation results in a large output, the calculated data is displayed through four separate frames on the form: effluent quality, pollutant percent removed, evaluation criteria scores and costs and resources.

The distribution system performance computational module is used to optimally size the distribution system elements. The sizing is carried out based on a pre-determined branched layout and preferences of the user for locating the pumping and storage facilities, entered using a user-friendly interface. The method used is a two-step procedure that first determines the optimal allocation of reclaimed water (along with optimal sizes of seasonal storage), followed by the sizing of pipes and pumping stations.

In addition to allowing the software user to evaluate a large number of design alternatives using the simulation component of WTRNet, the software includes optimisation routines for conducting the least-cost planning of integrated water reuse systems. The verified simulation software was used as basis for the optimisation components, initially to determine the numbers of possible design alternatives involving different end-uses and numbers of customers. This results of this exercise showed that incorporating a single optimisation methodology would not be appropriate, since the number of design alternatives changes by several orders of magnitude, depending on the influent quality an the number of potential end-users considered.

In order to accommodate the wide range of the number of possible design alternatives, three algorithms are incorporated in the optimisation module. If the secondary effluent is to be reclaimed and the number of potential customers is not large, exhaustive enumeration is used to determine the least-cost design alternatives for all combinations of end-users. If the secondary effluent is to be reclaimed for a (potentially) large number of end-users, a simple Genetic Algorithm (GA) is used for optimal user selection. Finally, if the source of water is raw sewage or primary effluent, the optimisation algorithm used is a GA with customised operators. The algorithm conducts a simultaneous search of least-cost design alternatives and the best selection of customers.

The WTRNet decision support tool provides a platform that can be used to conduct the integrated assessment of water reuse options in an efficient manner. The tool has been successfully applied on a case study of water reuse options in the city of Kyjov, Czech Republic, and London, England.

AquaStress is a four year (2005-2009) Integrated Project (IP) funded by the European Commission in the frame of the 6th R&D Framework Programme, with contributions from 35 renowned organizations, including SMEs, from 17 countries.

Water stress is a global problem with far-reaching economic and social implications. The mitigation of water stress at regional scale depends not just on technological innovations, but also on the development of new integrated water management tools and decision-making practices. The AquaStress IP delivers enhanced interdisciplinary methodologies enabling actors at different levels of involvement and at different stages of the planning process to mitigate water stress problems. The IP draws on both academic and practitioner skills to generate knowledge in technological, operational management, policy, socio-economic, and environmental domains.

This IP draws on both academic and practitioner skills to generate knowledge in technological, operational management, policy, socio-economic, and environmental domains.

AQUASTRESS will generate scientific innovations to improve the understanding of water stress from an integrated multisectoral perspective to support:

  • diagnosis and characterisation of sources and causes of water stress;
  • assessment of the effectiveness of water stress management measures and development of new tailored options;
  • development of supporting methods and tools to evaluate different mitigation options and their potential interactions;
  • development and dissemination of guidelines, protocols, and policies;
  • development of a participatory process to implement solutions tailored to environmental, cultural, economic and institutional settings;
  • identification of barriers to policy mechanism implementation;
  • continuous involvement of citizens and institutions within a social learning process that promotes new forms of water culture and nurtures long-term change and social adaptivity.

The IP adopts a Case Study stakeholder driven approach and is organised in three phases:

  • characterisation of selected reference sites and relative water stress problems,
  • collaborative identification of preferred solution options,
  • testing of solutions according to stakeholder interests and expectations.

It will make a major contribution to the objectives of the Global Change and Ecosystems and supporting the Community Directive 2000/60/EC and the EU Water Initiative.

EXETER/CWS Contribution to AQUASTRESS:

CWS Contribution to AQUASTRESS is the application of Conceptual Modelling, Systems Thinking and System Dynamics Modelling (SDM) for the simulation of the project’s case studies for complex dynamical water and/or environmental systems, that will act as Decision Support Tools, examining various operational scenarios, integrating different technical options for the mitigation of water stress.

SDM is a methodology for studying and managing complex feedback systems. It is typically used when formal analytical models do not exist, but where system simulation can be developed by linking a number of feedback mechanisms. This type of Systems Modelling, being lower in detail and higher in integration, allows the domain experts and the local stakeholders to explore the relationship between various technical options and the overall system behaviour and to increase their understanding of the interactions and impacts among different water system components.

So far there have been two case studies within AQUASTRESS, where SDM has been applied

  • The water system of Kremikovtzi (Bulgaria), where the aim is to reduce clear water consumption and increase water re-use within the plan 
  • The Merguellil valley water system (Tunisia), a hydrological/water resources management model, involving a semi-arid area with increased irrigation demands, including 25 small dams for rainfall harvesting, a large reservoir (El Haouareb) and aquifer recharge.

SDM Software specifications

SDMs are implemented in special visual environments that enable the user to effectively "draw" the system components and their interrelations and run different scenarios. SIMILE® for numerical and VENSIM® for causal-qualitative diagrams have been used for building the models.

Publications

  • VAMVAKERIDOU-LYROUDIA, L.S. and SAVIC D.A. (2008). "System Dynamics Modelling: The Kremikovtzi Water System", Report No.2008/01, Centre for Water Systems, School of Engineering, Computing and Mathematics, University of Exeter, UK, 132p
  • VAMVAKERIDOU-LYROUDIA, L.S., SAVIC, D.A., TARNACKI K., WINTGENS T., DIMOVA, G. and RIBAROVA I. (2007). "Conceptual/System Dynamics Modelling Applied for the Simulation of Complex Water Systems", in Water Management Challenges in Global Change, Proc. Int. Conf. CCWI 2007 & SUWM 2007, Leicester UK, 3-5 Sept. 2007, Taylor & Francis Group, London UK, pp. 159-167

Application: Kremikovtzi Water System

The Kremikovtzi metallurgical plant, near Sofia, Bulgaria, constructed initially in 1963, is one of the largest water consumers in the country (total fresh- water consumption 55×106 m3/year on average - roughly equivalent to the water needs of a city with a population of 600 000). Its water supply system is complex and consists of both freshwater (reservoirs, rivers, groundwater) and reused water sources (treated industrial waste water). It also provides water for a number of smaller satellite plants, sharing the same water resources. Some of the system’s freshwater sources are also used by urban and agricultural water users in the Sofia region, leading to regulations for priorities and upper limits to water consumption for industrial use, as well as water stress situations arising in times of drought. SDM has been developed and applied to the Kremikovtzi water system in order to simulate and study future operational scenarios, under varying climatic conditions ("normal", "dry" and "very dry" years) and operational rules.

The general scope for the scenarios and the simulation through SDM is to reduce clear water consumption and increase water re-use within the plan, as well as define suitable operational rules, that will allow the plant to operate under drought and water scarcity conditions. These rules involve hierarchical closure of some less important industrial units and/or reallocation of water resources, defined by the model.

The prototype application involves the water system of the Kremikovtzi industrial plant (Bulgaria), where the aim is to reduce clear water consumption and increase water re-use within the plan. A second application has also been developed for the simulation of the Merguellil Catchment (Tunisia), a hydrological/water resources management model, involving a semi-arid area with increased irrigation demands, a system of 25 small dams for rainfall harvesting, the operation of a large reservoir (El Haouareb) and aquifer recharge.

More related documents are available within our downloads.

The overall aim is to develop, implement, test/verify and hand over a Risk-based Decision Support System (DSS) to enable control room operators to react and remedy failures in the Yorkshire Water Services (YWS) water distribution system before they impact customers.

The DSS developed as part of this KTP will maximise the benefit of collecting real-time data for rapid evaluation of bursts and leaks in a Water Distribution System (WDS). A number of models and data sources will be integrated and the synergetic effect of combining advanced technologies with experience of human operators will be exploited by the DSS. Moreover, the DSS will reduce the cognitive load of human operators by presenting processed and relevant information, ultimately helping YWS to improve customer experience and deliver world class service.

Company: Yorkshire Water Services Limited

KTP Associate: Josef Bicik

Academic Supervisor: Prof. Zoran Kapelan

Project Length: 2.5 years (August 2010 - January 2013)

To promote the efficient use of resources there is a recognised need to make best use of existing infrastructure. Whole Life Costing (WLC) in combination with computational optimisation techniques has been used to satisfy this need. WLC methodologies consider all the costs (private & social) that accrue to initiation, provision, operation, maintenance, servicing and decommissioning, over the useful life of a service facility. Application of WLC to (capital and operational) management of water distribution networks has been based on detailed consideration of holistic performance and explicit linking of costs to their drivers. Decision Modelling links the Costs and Performance frameworks via WLC Scenario Management Software called WiLCO.

WiLCO incorporates an optimisation module to find the least Whole Life Cost management solution within the user defined performance/risk/cost scenario. All aspects of performance which impact on costs accruing to any party are considered resulting in the derivation of six integrated performance sub-modules; Leakage, Demand, Structural Performance, Customer Interruptions, Water Quality, Hydraulic Capacity. These sub-modules quantify current and future performance and the effect on performance of interventions, e.g. pipe replacements and changes in operational strategy, at given time horizons.

This two-centre project between the Centre for Water Systems (University of Exeter) and the Pennine Water Group (University of Sheffield) and has been carried out in close collaboration with the water industry. Collaborators included water companies (Yorkshire Water, United Utilities, South West Water, Thames Water, Lyonnaise des Eaux), a consultant (Ewan Group), and a software provider (Geodesys).

The project outputs satisfy the aims of the WITE programme through which it was funded. The programme was established to promote research collaboration between universities and the water utilities, providing the basis for solutions to problems faced by the water industry and providing a supply of skilled people, trained in water engineering research. The key objective of the programme, dissemination and exploitation of the research outputs, through close collaboration with water utilities.

The project was funded by the UK Engineering and Physical Sciences Research Council (EPSRC) under the Water Infrastructure and Treatment Engineering (WITE) programme. and end-users, has been fully achieved as evidenced by the project outputs.

More about the project (partners, outcomes, Powerpoint presentations,etc) can be found on our dedicated website.

References

  • Engelhardt, M.O., Skipworth, P.J., Cashman, A., Savic, D., Saul, A.J., Walters, G.A. (2002) A Whole Life Costing for Water Distribution Network Management, Thomas Telford Ltd, London UK (ISBN 0-7277-3166-1), pages 216.
  • Engelhardt, M.O., Skipworth, P.J., Cashman, A., Savic, D., Walters, G.A., Saul, A.J., (2002) Applying Whole Life Costing to Water Distribution Network Management. Accepted for publication in Urban Water Journal.
  • Engelhardt, M.O., Skipworth, P.J., Cashman, A., Savic, D., Walters, G.A., Saul, A.J., (2002) Determining Maintenance Requirements of a Water Distribution Network using Whole Life Costing. J. Quality and Maintenance Engineering, Vol. 8, No. 2 (in press).
  • Skipworth, P.J., Engelhardt, M.O., Cashman, A., Savic, D., Walters, G.A., Saul, A.J., (2002) Performance Modelling in a Whole Life Costing Approach to Water Distribution Network Management. Submitted to ICE J. Water and Maritime Engineering
  • Skipworth P.J. (2002) Whole Life Costing for Sustainable Infrastructure - a focus on water distribution networks. Feature Article "Sustain - Built Environment Matters", Volume 3, Issue 3, McClelland Publishing.
  • Engelhard, M.O., Skipworth, P.J., Savic, D., Walters, G.A., Saul, A.J., Cashman, A., (2002) WiLCO: Whole Life Costing Software. Accepted for publication at ASCE/EWRI Annual Conference, Roanoke, Virginia, May 19-22.
  • Engelhardt, M.O., Savic, D., Walters, G.A., Skipworth, P.J., Saul, A.J., Cashman, A., (2002) Whole Life Costing methodology for Water Distribution Network Management. Accepted for publication at Enviro 2002, Melbourne, Australia.
  • Skipworth, P.J., Cashman, A., Engelhardt, M.O, Saul, A.J, Savic, D.A., and Walters, G.A. (2001) Incorporation of leakage in a whole life costing approach to distribution network management. In Water Software Systems: Theory and Applications, Vol. 1, Ulanicki, B., Coulbeck, B. and Rance, J.P. (eds.), Research Studies Press, Baldock, Hertfordshire, England, pp. 49-59.
  • Skipworth, P.J., Cashman, A., Engelhardt, M.O., Saul, A.J., Savic, D.A. (2001) Quantification of Mains Failure Behaviour in a Whole Life Costing Approach to Distribution System Management. World Water & Environmental Resources Congress, May 20-24, Orlando, Florida, edited by Phelps, D. and G. Sehlke (proceeding published on CD), p. 10.
  • Engelhardt, M.O., Skipworth, P.J., Cashman, A., Savic, D.A., Saul, A.J., Walters, G.A. (2001) Incorporation of water quality in a whole life costing approach to distribution network management. 4th International Conference on Water Pipeline Systems - "Managing Pipeline Assets in an Evolving Market", March 2001.
  • Engelhardt, M.O., Skipworth, P.J., Savic, D.A., Saul, A.J., Walters, G.A. (2000) Rehabilitation strategies for water distribution networks. Urban Water, Vol. 2, No. 2, pp. 153-170.
  • Skipworth, P.J., Saul, A.J. and Engelhardt, M.O. (2000) Distribution network behaviour - extracting knowledge from data. Int. Symposium on Water Network Modelling for Optimal Design and Management , Exeter, UK.
  • Engelhardt, M.O., Savic, D.A., Walters, G.A. (1999) Using genetic algorithms to optimise water distribution system rehabilitation, 9th International MIRCE Symposium on System Operational Effectiveness, Knezevic, J., U.D Kumar and C. Nicholas (eds.), Woodbury, UK.

An EPSRC project titled 'Inverse Transient Analysis in Pipe Networks for Leakage Detection, Quantification and Roughness Calibration' was executed jointly by Exeter University (EU, GR/M66981/01) and Imperial College (IC). The project was initiated around the idea of detecting leaks in water distribution systems (WDS) by calibrating the transient simulation model for unknown nodal leaks (Liggett et al., 1994). During the project, EU's part of the research work was to concentrate on the improvement of existing methodologies for WDS model calibration and sampling design.

The project was (and is still being) disseminated scientifically via multiple journal and conference publications. A full list of publications can be found in the accompanying Interim Report. The EU part of the project was led jointly by Prof. D. Savic and Prof. G.A. Walters. The research work was carried out by Dr Z. Kapelan.

While the project has been disseminated successfully in scientific terms it has yet to be exploited commercially. It is envisaged that the best way to do this is to transfer the relevant knowledge from EU to one of the project participants, a company called Ewan Optimal Solutions Ltd (EOSL). It is also envisaged that the most suitable person to do the actual transfer would be the RA on secondment from EU. In return, EOSL will provide training for the RA with the aim of enhancing his competencies.

The main objectives of the proposed collaboration between EU and EOSL are as follows:

  1. Transfer of the research knowledge gained during the original EPSRC project from EU to EOSL
  2. Enhancement of research assistant's competencies.

Funding body: Ewan Optimal Solutions Ltd.

Development work resulted in the software programs, GAnet and GAcal, which have been used on commercial projects involving hydraulic model calibration, design of water distribution network reinforcement and rehabilitation schemes and the optimization of level controlled pumping station operation. GAcal has also been sold commercially. Current development work is aimed at integrating GAnet with OpenNet, a library of C++ classes that provide the facilities for modelling water networks.

References

  1. Morley, M.S., R.M. Atkinson, D.A. Savic and G.A. Walters, (2001) GAnet: Genetic Algorithm platform for pipe network optimisation, Advances in Engineering Software, Vol. 32. No. 6, pp. 467-475.
  2. Savic, D.A., G.A. Walters, R.M. Atkinson, M. Randall-Smith (1999), Genetic Algorithm Optimization of Large Water Distribution System Expansion, Journal of Measurement and Control, Vol.32, No.4, pp.104-109.
  3. Atkinson, R.M., M.S. Morley, D.A. Savic and G.A. Walters (1998), GANET: The Integration of GIS, Network Analysis and Genetic Algorithm Optimization Software for Water Network Analysis, Hydroinformatics 98, Babovic, V. Larsen, L.C. (eds.), Balkema, Rotter-dam, pp. 357-362.
  4. Walters, G.A., D.A. Savic, R. Thurley, D. Halhal, Z. Kapelan and R. Atkinson, (1999), Optimal Design of Water Systems Using Genetic Algorithms: Some Recent Developments, in Computing and Control for the Water Industry, R. Powell and K.S. Hindi (eds.), Research Studies Press, Baldock, Hertfordshire, England, pp. 337-344.
  5. Savic, D.A., G.A. Walters, M. Randall-Smith and R.M. Atkinson (2000), Large Water Distribution Systems Design through Genetic Algorithm Optimisation, ASCE 2000 Joint Conference on Water Resources Engineering and Water Resources Planning and Man-agement, July 30-August 2, Minneapolis, USA, edited by Hotch-kiss, R.H. and M. Glade (proceeding published on CD), p. 10.
  6. Morley, M.S., R.M. Atkinson, D.A. Savic and G.A.Walters (2000) OpenNet: An application-independent framework for hydraulic network representation, manipulation & dissemination, presented at the Hydroinformatics 2000 Conference, Iowa City, USA, 23-27 July (proceeding published on CD), p. 10.
  7. Atkinson, R.M.A., van Zyl, J.E., G.A. Walters and D.A. Savic, (2000) Genetic Algorithm Optimisation of Level-Controlled Pumping Station Operation, Water Network Modelling for Optimal Design and Management, CWS 2000, Centre for Water Systems, Exeter, UK, pp. 79-90.

The joint project between the Exeter University's Centre for Water Systems and Imperial College is aimed at developing an integrated, inverse-transient approach to leakage detection and model calibration.

Collaborators: Imperial College (Academic), Yorkshire Water, Bristol Water, Thames Water, Anglian Water, Ewan Optimal Solutions and UKWIR (Industrial)

Visit the project website >>

In more detail, the initial objectives were as follows:

  1. Development of a new numerical modelling approach by combining the inverse transient analysis (IC), steady-state and transient network analyses and genetic algorithms optimisation (EU) to enable optimal selection of pressure measurement sites for leakage detection and pipe roughness calibration
  2. An experimental programme under strictly controlled laboratory conditions and simulated leaks in pipelines (IC and Thames Water) aimed at acquiring reliable sets of both steady state and transient flow data for testing of the methodology, calibration and verification of the programs
  3. Development of a data mining or some other procedure for establishing rules on how to select pressure measurement sites in new networks (EU)
  4. Field tests (full scale water supply system of Anglian Water) for obtaining reliable sets of transient flow data and their application in the inverse transient method for leak detection and calibration (IC&EU)
  5. Analysis of the methodology on the basis of uncertainty reduction and data reliability improvement (IC&EU), for possible application in the UK Water Industry
  6. Analysis of trends and future research needs.

The research work carried out has resulted in the development of new or improved calibration and sampling design methodologies. All methodologies presented here were coded for testing purposes. Coding was done in the C++ programming language. A brief summary of the new or improved methodologies is given here below.

Initially, a transient simulation model (i.e. software) for any pipe network configuration was developed. Software for the calculation of the Jacobian matrix (i.e. partial derivatives of model predictions with respect to analysed calibration parameters) was developed for transient, steady-state and extended-period simulation model cases. It was necessary to develop such software for: (a) application of gradient type optimisation methods, e.g. the Levenberg-Marquardt method; (b) use of post-calibration statistical analysis and (c) solving the optimal sampling design problem. For steady-state and extended period simulation (EPS) hydraulic models two methods were developed and coded: the sensitivity equation method and the adjoint method. For the transient WDS model, a novel method based on a variation of the existing sensitivity equation method (Nash et al., 1999) was developed to support any pipe network configuration. An improved approach for the calibration of WDS hydraulic models was developed. Its main characteristics are as follows:

  • Approach can be applied for the calibration of all major WDS hydraulic models: (a) steady-state flow model, (b) EPS model and (c) transient model.
  • The calibration problem is formulated as a constrained optimisation problem with prior information on parameters incorporated in the objective of weighted least square type (Kapelan et al., 2001c; Kapelan et al., 2001e).
  • Two existing (genetic algorithm (GA) and Levenberg-Marquardt (LM)) and two novel, hybrid optimisation methods were developed to solve the analysed calibration problem. The hybrid methods were named GALM (Kapelan et al., 2000) and HGA (Kapelan et al., 2001a; Kapelan et al., 2001b; Kapelan et al., 2002b; Kapelan et al., 2002a).
  • The use of diagnostic statistics and analysis to identify ill-posed calibration problems and to provide partial insight into the calibration process.
  • Use of various statistics to thoroughly evaluate calibration process results in terms of: (a) model fit, (b) uncertainties (i.e. errors) associated with estimated calibration parameters, (c) uncertainties (i.e. errors) associated with calibrated model predictions.

A novel sampling design approach for calibration of WDS hydraulic models was developed. Its main characteristics are as follows:

  • The sampling design problem is formulated as a multi-objective optimisation problem. The two main objectives are: (a) maximise calibration accuracy by minimising calibrated model uncertainty and (b) minimise total sampling design costs.
  • Three calibration accuracy objectives were analysed: (1) D-optimality (Kapelan et al., 2001d), (2) A-optimality (Kapelan, 2002) and (3) V-optimality (Kapelan et al., 2002e; Kapelan et al., 2002c). Therefore, both model parameter and prediction uncertainties were analysed.
  • A new single-objective GA (SOGA) optimal sampling design model (Kapelan et al., 2002f; Kapelan et al., 2002g) was developed. The sampling design problem was formulated as a single-objective problem and solved using a standard GA optimisation method. Two objectives are recombined into a weighted single one after normalisation.
  • A new multi-objective GA (MOGA) optimal sampling design model (Kapelan et al., 2002d) was developed based on Pareto domination,. The aim was to treat and solve the sampling design problem as a true multi-objective optimisation problem. The MOGA methodology is based on Pareto domination rules, restricted mating and niching. The new MOGA approach was compared to several well-known SD methods from the literature (Ferreri et al., 1994; Bush et al., 1998; De Schaetzen et al., 2000).

All developed calibration and sampling design approaches were tested and verified on multiple case studies involving both relatively simple, small artificial WDS networks and relatively large, complex real-life WDS networks (Kapelan, 2002).

Since the first results of the research work were published, UK water companies have shown substantial interest in the developed technology. As a result, the EPSRC has recently approved for the research assistant (Dr Kapelan) to be seconded to Ewan Optimal Solutions Ltd, a company collaborating on the original project, on a Research Assistant Industrial Secondment (RAIS) scheme.

References

  • Kapelan, Z.S. (2002), "Calibration of WDS Hydraulic Models", PhD Thesis, Department of Engineering, University of Exeter, 334pp.
  • Kapelan, Z.S., Savic, D.A., and Walters, G.A. (2000), "Inverse Transient Analysis in Pipe Networks for Leakage Detection and Roughness Calibration", Proc. Water Network Modelling for Optimal Design and Management, Exeter, UK, D. A. Savic and G. A. Walters, eds., vol. 1, 143-159.
  • Kapelan, Z.S., Savic, D.A., and Walters, G.A. (2001a), ?A Hybrid Inverse Transient Model for Leakage Detection and Roughness Calibration in Pipe Networks (1): Theoretical Development?, Journal of Hydraulic Research (IAHR), (accepted for publication).
  • Kapelan, Z.S., Savic, D.A., and Walters, G.A. (2001b), ?A Hybrid Inverse Transient Model for Leakage Detection and Roughness Calibration in Pipe Networks (2): Applications?, Journal of Hydraulic Research (IAHR), (accepted for publication).
  • Kapelan, Z.S., Savic, D.A., and Walters, G.A. (2001c), ?Incorporation of Prior Information on Parameters in Inverse Transient Analysis for Leak Detection and Roughness Calibration?, Urban Water, (accepted for publication).
  • Kapelan, Z.S., Savic, D.A., and Walters, G.A. (2001d), "Optimal Sampling Design Methods for Calibration of Water Supply Network Models", Proc. International Conference on Computing and Control for the Water Industry CCWI 2001, De Montfort University, Leicester, UK, D. Ulanicki, B. Coulbeck and J. P. Rance, eds., vol. 1, 99-109.
  • Kapelan, Z.S., Savic, D.A., and Walters, G.A. (2001e), "Use of Prior Information on Parameters in Inverse Transient Analysis for Leak Detection and Roughness Calibration", Proc. World Water & Environmental Resources Congress, Orlando, USA, CD-ROM edition.
  • Kapelan, Z.S., Savic, D.A., and Walters, G.A. (2002a), "Hybrid GA for Calibration of Water Distribution System Hydraulic Models", Proc. 1st Annual Environmental & Water Resources Systems Analysis (EWRSA) Symposium, Roanoke, Virginia, USA, CD-ROM edition.
  • Kapelan, Z.S., Savic, D.A., and Walters, G.A. (2002b), "A Hybrid Search Technique for Inverse Transient Analysis in Water Distribution Systems", Proc. 5th International Conference on Adaptive Computing in Design and Manufacture, Exeter, UK, I. C. Parmee, ed., vol. 1, 75-86.
  • Kapelan, Z.S., Savic, D.A., and Walters, G.A. (2002c), "Multi-objective GA Solution to Problem of Optimal Sampling Design for WDS Hydraulic Model Calibration", Proc. 5th International Conference on Hydroinformatics, Cardiff, UK, vol. 2, 1435-1440.
  • Kapelan, Z.S., Savic, D.A., and Walters, G.A. (2002e), "Multi-objective Sampling Design for Water Distribution Model Calibration", Proc. 3rd International Conference on Environmental Management, Johannesburg (RSA).
  • Kapelan, Z.S., Savic, D.A., and Walters, G.A. (2002d), ?Multi-objective Sampling Design for Water Distribution Model Calibration?, Journal of Water Resources Planning and Management, ASCE, (submitted for publication).
  • Kapelan, Z.S., Savic, D.A., and Walters, G.A. (2002f), ?Optimal Sampling Design Methodologies for Water Distribution Model Calibration: 1. Theory?, Water Resources Research, (submitted for publication).
  • Kapelan, Z.S., Savic, D.A., and Walters, G.A. (2002g), ?Optimal Sampling Design Methodologies for Water Distribution Model Calibration: 2. Applications?, Water Resources Research, (submitted for publication).

iWIDGET’s focus is a more integrated approach to water resources management and the project will contribute to delivering a sustainable, low-carbon society, helping progress towards the Europe 2020 targets on Climate and Energy. This approach will be developed by researching, developing, demonstrating and evaluating a fully integrated ICT-based system of techniques and technologies that will encourage and enable householders and water suppliers to understand and manage down their demand and minimise wastage in the supply chain.

The Project is being led by Prof. Dragan Savić, Founder and Co-director of the Centre for Water Systems at the University of Exeter.

The partnership assembled to deliver the iWIDGET project is a combination of all the key players in the field, leading ICT companies, business leaders, technology developers, standardisation organisations, water companies and top scientists in the field of water management, information and systems analysis and the social sciences. See the iWIDGET web site for more details.

Together the WIDGET consortium brings to the table a clear understanding of the market, the technological state-of–the-art with respect to hardware and software, new research and development in data mining, analytics, decision support, scenario modelling, data management, standards interfaces, visualisation, water conservation modelling and social simulation. The project will also obtain input from householders through two case studies and input from the broader water industry through its Advisory Panel.

For further information, please see the iWIDGET website.

The central tenet of the NeWater project is a transition from currently prevailing regimes of river basin water management into more adaptive regimes in the future. This transition calls for a highly integrated water resources management concept. NeWater identifies key typical elements of the current water management system and focuses its research on processes of transition of these elements to adaptive IWRM.

Each key element is studied by novel approaches. Key IWRM areas where NeWater is expected to deliver breakthrough results include:

  • governance in water management (methods to arrive at polycentric, horizontal broad stakeholder participation in IWRM)
  • sectoral integration (integration of IWRM and spatial planning; integration with climate change adaptation strategies, cross-sectoral optimisation and cost-benefit analysis)
  • scales of analysis in IWRM (methods to resolve resource use conflicts; transboundary issues)
  • information management (multi stakeholder dialogue, multi-agent systems modelling; role of games in decision making; novel monitoring systems for decision systems in water management)
  • infrastructure (innovative methods for river basin buffering capacity; role of storage in adaptation to climate variability and climate extremes)
  • finances and risk mitigation strategies in water management (new instruments, role of public-private arrangements in risk-sharing)
  • stakeholder participation; promoting new ways of bridging between science, policy and implementation

The development of concepts and tools that guide an integrated analysis and support a stepwise process of change in water management is the corner-stone of research activities in the NeWater project. To achieve its objectives the project is structured into six work blocks, and it adopts a management structure that allows effective exchange between innovative and cutting edge research on integrative water management concepts, with practical applications and testing through participatory stakeholder processes in selected river basins.

Funding body: Teaching Company Directorate, DTI and Ewan Optimal Solutions Ltd.

Calibration of computer models for network analysis is a regular component of the model building process. The process generally first involves a series of field tests during which pressures and flows are recorded at strategic locations in the system. This is followed by a desk exercise during which adjustments are made to the roughness values used in modelling the system until a satisfactory match is obtained between modelled and observed values. The selection of a satisfactory set of roughness values can be a tedious business when undertaken by the traditional trial and error approach. In this work, several methodologies were proposed to assist the modeller in the following two tasks: firstly in the selection of sensitive sampling locations in a water distribution system and secondly in the derivation of a good calibrated hydraulic network model. A new calibration approach which consists of adjusting the pipe roughness, the pipe diameter and the nodal demand which certain limits, is proposed by using a genetic algorithm search method.

Three new sampling design approaches were also proposed. The first two approaches rank potential sampling locations based on the shortest path algorithm logic, while the third approach searches for the optimal set of monitoring points by maximising the entropy function using a genetic algorithm search method. The calibration and sampling design approaches are demonstrated by using six hydraulic network models, including three real-life networks. The calibration results show that the genetic algorithm approach consistently achieves more accurate fits than manually worked solutions while the sampling design results demonstrate the potential for financial savings through more efficient equipment deployment.

References

  • De Schaetzen, W.B.F. (2000) Optimal Calibration and Sampling Design for Hydraulic Network Models, PhD thesis, University of Exeter.
  • De Schaetzen, W.B.F., G.A. Walters and D.A. Savic, (2000), Optimal Sampling Design for Model Calibration Using Shortest Path, Genetic and Entropy Algorithms, Urban Water, Vol. 2, No. 2, pp. 141-152.
  • De Schaetzen, W., V.J. Ewan, D.A. Savic and G.A. Walters (1998), A Genetic Algorithm Approach for Rehabilitation in Water Supply Systems, International Conference on Rehabilitation Technology for the Water Industry, Lille, France, 23-25 March.
  • De Schaetzen, W., D.A. Savic and G.A. Walters (1998), Genetic Algorithms for Pump Scheduling and Cost Optimization in Water Supply Systems, Hydroinformatics 98, Babovic, V. Larsen, L.C. (eds.), Balkema, Rotterdam, pp. 897-899.
  • Walters, G.A., D.A. Savic, M.S. Morley, W. de Schaetzen and R.M. Atkinson (1998) Calibration of Water Distribution Network Models Using Genetic Algorithms, in Hydraulic Engineering Software VII, Blain, W.R. (ed.), Computational Mechanics Publications, pp. 131-140.
  • De Schaetzen W., D.A. Savic, G.A. Walters and M. Randall-Smith (1999) Optimal Loger Density in Water Distribution Network Calibration, in Water Industry Systems: Modelling and Optimisation Applications, Vol. 1, Savic, D.A. and G.A. Walters (eds.), Re-search Studies Press, Baldock, Hertfordshire, England, pp. 301-308.

The problem of choosing the best possible set of network improvements to make with a limited budget is presented as a large optimisation problem to which conventional optimisation techniques are poorly suited. A multi-objective approach is developed, using capital cost and benefit as dual objectives, enabling a range of non-inferior solutions of varying cost to be derived. A Structured Messy Genetic Algorithm is developed, incorporating some of the principles of the Messy Genetic Algorithm, such as strings which increase in length during the evolution of designs. The algorithm is shown to be an effective tool for the current optimisation problem, being particularly suited both to the multi-objective approach and to problems which involve the selection of small sets of variables from large numbers of possibilities.

References

  • Halhal, D. (1998) "Optimal Improvement of Water Distribution Systems", PhD Thesis, University of Exeter
  • Halhal, D., G.A. Walters, D. Ouazar, and D.A. Savic, (1997), Multi-Objective Improvement of Water Distribution Systems Using a Structured Messy Genetic Algorithm Approach, ASCE Journal of Water Resources Planning and Management, Vol. 123, No. 3, pp. 137-146.
  • Halhal, D., G.A. Walters, D.A. Savic and D. Ouazar, (1999), Scheduling of Water Distribution System Rehabilitation using Structured Messy Genetic Algorithms, Evolutionary Computation, Vol. 7, No. 3, pp. 311-329.
  • Walters, G.A., D.Halhal, D.A,Savic and D.Ouazar (1999), Im-proved Design of ?Anytown? Network Using Structured Messy Genetic Algorithms, Urban Water, Vol. 1, No. 1, pp. 23-38.
  • Halhal, D., G.A. Walters, D. Ouazar and D.A. Savic, (1995), Us-ing Genetic Algorithm Hybrids for the Optimal Improvement of Water Distribution Systems, presented at the third international conference on Computer Methods and Water Resources CMWR ?95, Beirut, Lebanon.
  • Walters, G.A., D.A. Savic, R. Thurley, D. Halhal, Z. Kapelan and R. Atkinson, (1999), Optimal Design of Water Systems Using Genetic Algorithms: Some Recent Developments, in Computing and Control for the Water Industry, R. Powell and K.S. Hindi (eds.), Research Studies Press, Baldock, Hertfordshire, England, pp. 337-344.
  • Halhal, D., G.A. Walters, D.A. Savic and D. Ouazar (1999) Optimal Phasing of Water Distribution Systems Rehabilitation, in Water Industry Systems: Modelling and Optimisation Applications, Vol. 2, Savic, D.A. and G.A. Walters (eds.), Research Studies Press, Baldock, Hertfordshire, England, pp. 437-448.

'Prepared: Enabling Change' is a large scale integrating interdisciplinary project funded by the European Commission Seventh Framework Program (EC FP7) . IPCC climate change scenarios have a global perspective and need to be scaled down to the local level, where decision makers have to balance risks and investment costs. Very high investments might be a waste of money and too little investment could result in unacceptable risks for the local community. PREPARED is industry driven. 12 city utilities are involved in the project and the RDT carried out is based on the impacts of climate change the water supply and sanitation industry has identified as a challenge for the years to come.

The result of PREPARED will be an infrastructure for waste water, drinking water and stormwater management that will not only be able to better cope with new scenarios on climate change but that is also managed in an optimal way. PREPARED involves the local community in problem identification and in jointly finding acceptable system solutions, that are supported by all, through active learning processes.

Cities

In order to make the results from PREPARED applicable to the everyday world, the work is being undertaken and applied to several 'demonstration' cities. The results from each of these cities will be adapted and applied to other demonstration cities in PREPARED, and then hopefully on a much more wider, global scale so that cities around the world can learn and start to take action to make their water systems more resilient to future global climate change. The demonstration cities in PREPARED are:

  • Aarhus
  • Barcelona
  • Berlin
  • Eindhoven
  • Genoa
  • Istanbul
  • Gilwice
  • Lisbon
  • Lyon
  • Melbourne
  • Oslo
  • Simferopol
  • Seattle

Exeter's involvement

Quantitative risk assessment

CWS is the leader in the Work Package dealing with Quantitative Risk Assessment (QRA). The aims are to develop models for the assessment of social, environmental and economic risks related to the sustainable performance of water systems under changing climate conditions. Categories of risk related to urban water systems will be defined, and methods for deterministic and stochastic QRA will be defined, developed and implemented. Our partner demonstration city is Eindhoven (Netherlands). Figure 1 shows the iterative framework within which this work is placed, and illustrates the need for cooperation.

Best location of sensors

The objective is the development and the application of methods for optimal macro-location for sensors in order to provide useful and reliable measurements in urban water systems, at whole-network scale, where the objective is to optimally locate a limited number of sensors to balance the cost and model prediction accuracy

Modelling: calibration, uncertainty assessment, data assimilation

The University of Exeter-CWS is leading the work package for urban water system modelling. It includes the investigation of methodologies for uncertainty quantification in urban water systems modelling and identifying possible steps that can be taken to reduce all types of uncertainty in real-time modelling through calibration, verification and data assimilation. The detailed aims are to:

  1. evaluate new and existing methods for uncertainty quantification
  2. develop a toolbox of most promising uncertainty quantification methods
  3. investigate the potential of data assimilation schemes to reduce uncertainty associated with real-time modelling i.e. make real-time models more accurate and;
  4. develop recommendations on best practice and guidelines on the proper application of uncertainty quantification and data assimilation techniques in UWS modelling to help end-users in their applications.

Integrated real-time monitoring, modelling and control platform

The objective is to enhance the capability of existing measures and forecasting technologies by extending the open integrated monitoring toolbox and database system with the capabilities

  1. accommodating and using in real-time existing model descriptions of the water cycle
  2. real-time calibration and data assimilation - extending the virtual sensors concept
  3. using existing control systems as front-ends in order to enable the use of new promising control strategies and decision support systems using overall on-line optimisation.

Decision support and early warning systems for source- and receiving waters

The expected increase of the frequency and severity of extreme events will lead to a more rapidly changing input to the water supply and sanitation infrastructure and consequently also affect the outputs to the receiving waters. In order to strengthen immediate management actions, the overall objective is to:

  • enhance the capability of existing measuring and forecasting technologies by integrating these with new monitoring and modelling approaches, enabling development of decision support and early warning systems for:
    1. Immediate management of the competing use and protection of water intakes and;
    2. Immediate management of the health risks related to unavoidable combined sewer overflows and uncontrolled runoff caused by more frequent and heavier rainfall and specific warnings for areas subject to recreational use.

Early warning and distributed control systems for water supply

Existing water supply systems have to adapt to an increased temperature caused by climate change, which will affect water quality. Less use of potable water caused by water scarcity leads to higher retention times in supply networks, which also might add to temperature increases. The aims here are

  1. enhance the capabilities of existing measuring and forecasting technologies in order to enable early warning of deteriorating water quality using advanced water quality and quantity sensors for real-time monitoring and modelling of distribution networks
  2. use overall on-line optimisation to operate new promising real-time control strategies for distributed disinfection control to cope with enhanced microbial regrowth at higher temperatures.

Partners

Visit the Prepared website for futher information.

 

NEPTUNE is a £2.7m joint EPSRC and industrially funded project bringing together seven academic and three industrial collaborators.  The aim of project NEPTUNE, is to advance knowledge and understanding about water supply systems in order to develop novel, robust, practical techniques and tools to optimize efficiency and customer service, through dynamic control or other means.

The key needs, identified by the industrial partners, to be addressed in project NEPTUNE are:

  • To deliver an optimised water distribution system
  • To be able to react to an incident before the customer is effected
  • To optimise the decision making process – to react to real alarms and incidents
  • To develop power harvesting techniques
  • To support the continued drive to reduce leakage
  • To develop innovation in pressure management to deliver key leakage and energy savings
  • To provide automated control and adjustment to the system
  • To build an integrated management system which will monitor leakage, energy, alarms etc
  • To develop online models to simulate the distribution network for the next 24 hours
  • To provide options to make significant savings in energy e.g. through pump schedule optimisation

The core deliverable of the Exeter team is an integrated, risk-based Decision Support System (DSS) for the rapid evaluation of intervention strategies to inform decision-making for sustainable water system operation. To ease the burden on system controllers and staff who are dealing with vast amounts of data, the DSS seeks to assist in: making optimal decisions, prioritizing the reaction to urgent events and identifying false or duplicated alarms.  The DSS facilitates the integration of these diverse outputs into a single, coherent application to be presented to the operator.

Project NEPTUNE is a collaborative project involving two leading UK Water Service Providers - Yorkshire Water Services and United Utilities - and a major provider of automation technologies - AAB. The research work is mainly carried out through the collaboration of several UK universities, including the University of Exeter.

Partners‌‌‌

   

Aims

The aim of the Exeter team is to develop an integrated, risk-based decision support system to evaluate intervention strategies and provide decision makers with the required information to operate a sustainable water system. The Centre for Water Systems, as a part of RPA3, carries out the research work in the following work packages:

  • Decision support system - To develop an integrated, risk-based decision support framework to support tactical (real-time) and strategic decision making.
  • Intervention management - To design and implement incident isolation and impact reducion strategies used within risk-based decision making.
  • Risk-based decision making - The aim is to develop a new general methodology for the management of risk and uncertainty associated with the decision making process for water supply networks.

Find out more about these aims on our dedicated webpage.

Outcomes

The project resulted in a prototype DSS currently being developed further through Knowledge Transfer Partnership projects with Yorkshire Water.

The project team at Exeter has filed a patent outlining the methodology developed for the NEPTUNE Decision Support System. We are currently in negotiations to sell our patent rights.

The following papers have been published so far:

  • Bicik, J., Kapelan, Z., Makropoulos, C. and D.A. Savić (2011) Pipe burst diagnostics using evidence theory, Journal of Hydroinformatics, Vol 13, No 4, pp. 596-608.
  • Savić, D.A., J.B. Boxall, B. Ulanicki, Z. Kapelan, C. Makropoulos, R. Fen-ner, K. Soga, I.W. Marshall, C. Maksimovic, I. Postlethwaite, R. Ashley and N. Graham (2008) Project NEPTUNE: improved operation of water distribution networks, Proceedings of the 10th Annual Water Distribution Systems Analysis Conference WDSA2008, Van Zyl, J.E., Ilemobade, A.A., Jacobs, H.E. (eds.), August 17-20, Kruger National Park, South Africa, pp. 543-558, CD-ROM.
  • Awad, H., Z. Kapelan and Savić, D.A. (2008) Analysis of pressure manage-ment economics in water distribution systems, Proceedings of the 10th An-nual Water Distribution Systems Analysis Conference WDSA2008, Van Zyl, J.E., Ilemobade, A.A., Jacobs, H.E. (eds.), August 17-20, Kruger National Park, South Africa, pp. 520-531, CD-ROM.
  • Bicik, J., C. Makropoulos, D. Joksimović, Z. Kapelan, M.S. Morley and Savić, D.A. (2008) Conceptual risk-based decision support methodology for improved near real-time response to WDS failures, Proceedings of the 10th Annual Water Distribution Systems Analysis Conference WDSA2008, Van Zyl, J.E., Ilemobade, A.A., Jacobs, H.E. (eds.), August 17-20, Kruger National Park, South Africa, pp. 510-519, CD-ROM.
  • Bicik, J., Savić, D.A. and Z. Kapelan (2009), Operation of water distribution systems using risk-based decision making, Integrating Water Systems, Boxall & Maksimovic (eds), Taylor and Francis, London, pp. 143-149.
  • Awad, H., Z. Kapelan and Savić, D.A. (2009), Optimal setting of time-modulated pressure reducing valves in water distribution networks using genetic algorithms, Integrating Water Systems, Boxall & Maksimovic (eds), Taylor and Francis, London, pp. 31-37.
  • Morley, M.S., J. Bicik, L.S. Vamvakeridou-Lyrouidia, Z. Kapelan and Savić, D.A. (2009), Neptune DSS: A decision support system near-real time operations management of water distribution systems, Integrating Water Systems, Boxall & Maksimovic (eds), Taylor and Francis, London, pp. 249
  • Vamvakeridou-Lyroudia, L.S., J. Bicik, H. Awad, M.S. Morley, Savić, D.A. and Z. Kapelan (2009), Developing and implementing a real-time intervention management model for water distribution systems, Integrating Water Systems, Boxall & Maksimovic (eds), Taylor and Francis, London, pp. 339-345.
  • Bicik, J., Z. Kapelan and Savić, D.A. (2009), Operational Perspective of the Impact of Failures in Water Distribution Systems, World Environmental and Water Resources Congress, Kansas City, Missouri, 17-21 May, 2009: Great Rivers, ASCE, p. 10, CD-ROM.
  • Bicik, J., C. Makropoulos, Z. Kapelan and Savić, D.A. (2009), The Application of Evidence Theory in Decision Support for Water Distribution System Operations, The 8th International Conference on Hydroinformatics, 12-16 Jan, Concepcion, Chile, CD-ROM.
  • Bicik, J., C. Makropoulos, Z. Kapelan and Savić, D.A. (2010) Risk-Based Prioritisation of Failures in Water Distribution System Operations, HIC2010, Tianjin, China.
  • Vamvakeridou-Lyroudia L.S., Bicik J., Morley M., Savić, D.A., Kapelan Z. (2010) A Real-Time Intervention Management Model For Reducing Impacts Due To Pipe Isolation In Water Distribution Systems, Water Distribution Systems Analysis 2010 - Proceedings of the 12th International Conference, WDSA 2010, pages 209-221.
  • Bicik, J., Kapelan, Z. and Savić D. A.  (2011) Challenges Of In The Imple-mentation Of A Decision Support System For Real-Time Operational Man-agement of Water Distribution Systems Management, Eleventh International Conference on Computing and Control for the Water Industry: Urban Water Management: Challenges and Opportunities, 5-7 Sept, Exeter, UK, p.8.

Funding body: ERASMUS scheme (European Community)

Cost minimisation is the main issue for water companies when establishing pumping regimes for water distribution. Energy consumption and pump maintenance represent by far the biggest expenditure, accounting for around 90% of the lifetime cost of a water pump. This work explores the development and use of multiobjective Genetic Algorithms for pump scheduling in water supply systems. The two objectives considered are minimisation of energy and maintenance costs. Pump switching is introduced as a surrogate measure of maintenance cost. The multiobjective algorithm is compared to the single objective GA, with both techniques improved by using hybridisation with a local-search method.

References

  • Mackle, G., D.A. Savic and G.A. Walters (1995), Genetic Algorithms for Pump Scheduling in Water Supply Systems, Centre For Systems And Control Engineering, Report No. 95/07, School of Engineering, University of Exeter, Exeter, United Kingdom, p.89.
  • Schwab, M., D.A. Savic and G.A. Walters (1996), Multi-Objective Genetic Algorithm for Pump Scheduling in Water Supply Systems, Centre For Systems And Control Engineering, Report No. 96/02, School of Engineering, University of Exeter, Exeter, United Kingdom, p.60.

Funding body: ERASMUS scheme (European Community)

The water industry in the United Kingdom spends approximately £70,000,000 per annum on electricity for pumping water supply. Similarly, almost 7% of the electricity consumed in the United States is used by the municipal water utilities. Since treated water pumping compromises the major fraction of the total energy budget, optimised operational schedules can improve the energy efficiency of a water distribution system. System operators make these operational schedules with the aid of special decision support software. This software is based on mathematical models, which can comprise several thousand components. During the search for an optimal operational schedule, those water network models are run many times for different input and operating conditions. However, only a few key results are normally necessary, so a simplified model which provides those outputs could be adequate.

Such a model should contain all the control components of the original model and the variables that are used to assess the quality of the operational policy. Ideally, simplified models will require less computation time and provide all information needed for the optimisation. Hence they could speed up the optimisation process and allow larger systems to be optimised. This project deals with simplification of water network models for the purpose of improving the running times of the simulation model.

References

  • Maschler, T. and D.A. Savic, (1999) Simplification of Water Supply Network Models through Linearisation, Centre for Water Systems, Report No.99/01, School of Engineering, University of Exeter, Exeter, United Kingdom, p.119.

The key aim of Urban Futures project is to envisage the future to enable us to make more sustainable decisions today. Partners in the project bring different expertise including biodiversity, air quality, water and wastewater, sub-surface built environment, surface built environment and open space, density and design decision making, social needs, aspirations and planning policy.

The three main linking elements of this research are urban regeneration, sustainability, and future scenarios. Initial work in the water sector is taking the agreed ‘futures’ developed in the project and quantifying their impact on water distribution network design and operation.

The project is led by the University of Birmingham.

WASSERMed is a European Commission Seventh Framework Program (EC FP7) funded interdisciplinary collaborative project that draws together experts from diverse backgrounds including water systems, agriculture, climate change analysis and social studies (see poster). It is one of three “sister projects” under the same theme of 'Climate induced changes in water resources', funded at the same time, focusing on water related threats from different point of views in the Mediterranean area (technical, meteorological, social). The other two projects are CLIMB (http://www.climb-fp7.eu/home/home.php) and CLICO (http://www.clico.org/).

The main aims of WASSERMed are:

  • to analyse current and future climate-induced changes to the hydrological budgets and extremes in southern Europe and the Mediterranean
  • to explore the implications of these changes under the framework of environmental, social and economic threats to security
  • to develop holistic/integrated modelling approaches to quantify the impact of climate change
  • to assess changes to mean flows and the extremes
  • to develop indicators for the examination and quantification of future water related security issues
  • to develop meaningful and realistic mitigation/policy options with project partners

Partners

Study areas

‌The results from WASSERMed aim to be applicable to the entire Mediterranean basin. Five case study areas have been chosen to reflect the diverse range of environments and causes of water-related security threats in the region, while research partners and stakeholders from all these regions participate in the project. The case study areas are:‌

 
  • Syros Island, Greece
  • Sardinia
  • Tunisia
  • Jordan River, Jordan
  • the Nile River, Egypt‌
 ‌

Exeter's involvement

System Dynamics Modelling

‌The Centre for Water Systems is the leader of the work package which involves developing and implementing water balance models, for each case study region, now and for the year 2050. Water demand will be estimated for 2050, with the aim being to assess the water-related security threats being posed to each case study area and to the wider Mediterranean basin as a result of potential  climate change scenarios and water shortages. Mitigating policy options will be defined and developed with local stakeholders in terms of absolute- and cost-effectiveness. System dynamics modelling (Fig. 1) is the tool being used in determining the water balance in each case study area, and to forecast future water use and demand. The work builds on previous experience of CWS with SDM for complex water systems at the EC FP6 project AQUASTRESS (2005-2009)

WASSERMed System Dynamics Modelling

Other areas of CWS involvement

  • Macroeconomic effects, trade and virtual water: Global assessment of water balance cases, where an  assessment on the impact of the effects on national economies is being made, and changes in production structure, demand patterns and productivity will be modelled.
  • Sensitive strategic sectors: Assessment of climate change effects on tourism and adaptation measures to climate change for the agricultural sectors in the case study areas.
  • Dissemination and awareness, including stakeholder involvement for participatory processes through project workshops at the case studies sites, training seminars and workshops on System  Dynamics Modelling, so that all partners have an understanding of the processes and methods involved in water balance quantification .

For more information see the WASSERMED poster

Outcomes

Peer-reviewed journal articles

  • Sušnik J., Vamvakeridou-Lyroudia L.S., Savić D.A., Kapelan Z., 2013. Integrated modelling of the water-agricultural system in the Rosetta region, Nile delta, Egypt, using system dynamics. Accepted in Journal of Water and Climate Change.
  • Sušnik J., Molina J-L., Vamvakeridou-Lyroudia L.S., Savić D.A., Kapelan Z., 2013. Comparative analysis of System Dynamics and Object-Oriented Bayesian Networks modelling for water systems management. Water Resources Management. 27(3): 819-841. DOI: 10.1007/s11269-012-0217-8.
  • Sušnik J., Vamvakeridou-Lyroudia L.S., Savić D.A., Kapelan Z., 2012, Integrated System Dynamics Modelling for water scarcity assessment: Case study of the Kairouan region. Science of the Total Environment. 440: 290-306. DOI: 10.1016/j.scitotenv.2012.050.085.

EU project reports

  • Sušnik J., Vamvakeridou-Lyroudia L.S., Savić D.A., Kapelan Z., 2012, Synthesis report on modelling and indicators for policy recommendations. WASSERMed Report 5.3.1. 89pp.
  • Sušnik J., Kampragrou E., Manoli E., Vamvakeridou-Lyroudia L.S., 2012, Preliminary report on water balance modelling for all case studies. WASSERMed Milestone 5.4. 46 pp.
  • Sušnik J., Manoli E.,Vamvakeridou-Lyroudia L.S., Savić D.A., Kapelan Z., 2012, Stakeholder consultation meetings on water balance modelling and evaluation: short report. WASSERMed Milestone 5.6. 16 pp.
  • Sušnik J., Manoli E., Kampragrou E., Mereu S., Vamvakeridou-Lyroudia L. S., Savić D.A., Kapelan Z., 2012, Report on water balancing for all case studies. WASSERMed Report 5.2.3. 72 pp.
  • Sušnik J., Manoli E., Vamvakeridou-Lyroudia L. S., Kampragrou E., Assimakopoulos D., Todorovic M., Mereu S., Roushdi M., El-Ganzouri A., Shatanawi M.S., Lili-Chabaane Z., Chakroun H., Oueslati I., Leduc C., Ogilvie A., Al-Naber G., Saba M., 2011, Water demand scenarios for the Case Studies. WASSERMed Report 5.1.2. 78 pp.
  • Sušnik J., Vamvakeridou-Lyroudia L.S., Savić D.A., Kapelan Z., 2012, Preliminary analysis of scenarios and options for all case studies. WASSERMed Milestone 5.5. 33 pp.
  • Sušnik J., Manoli E., Vamvakeridou-Lyroudia L. S., 2011, Definition, details and specifications of a database for modelling purposes. WASSERMed Report 5.1.1. 27 pp.
  • Sušnik J., Vamvakeridou-Lyroudia L. S., Manoli E., 2011, Report on modelling tools and techniques to be applied to each case study for water balancing. WASSERMed Report 5.2.2. 50 pp.
  • Sušnik J., 2010, Literature review and comparative analysis of the existing methodologies for water balance. WASSERMed Report 5.2.1. 34 pp.
  • Sušnik J., Manoli E., 2010, Selection of indicators for case studies. WASSERMed Milestone 5.1. 51 pp.

Conference proceedings

  • Sušnik J., Vamvakeridou-Lyroudia L. S., Savić D. A. and Kapelan Z., 2012, A System Dynamics Model assessing climate change impacts to the Rosetta region, Nile delta, Egypt. Proceedings of  the 10th International conference on Hydroinformatics, Hamburg, Germany, 13-18 July, 2012.
  • Sušnik J., Vamvakeridou-Lyroudia L. S., Savić D. A. and Kapelan Z.,2011, Evaluating water-related security threats for complex water systems using System Dynamics Modelling, Proceedings of the 11th International Conference on Computing and Control in the Water Industry, University of Exeter, Exeter, UK, 5-7 September 2011, pp. 71-76.
  • Sušnik J., Vamvakeridou-Lyroudia L. S., Savić D. A. and Kapelan Z.,2011, System Dynamics Modelling applied for the integrated simulation of complex water systems, Proceedings of the 8th IWA Symposium on Systems Analysis and Integrated Assessment, San Sebastian, Spain, 20-22 June 2011, pp. 535-542.

The overall objective of the Water4India project was to optimise and implement a set of technological alternatives for water supply in India.

The key objectives include:

  • Identify the main vulnerable areas suffering from water scarcity taking into account different factors such as current and future water availability, supply from centralized or decentralized sources, and qualitative and quantitative requirements of communities in the light of available sources and their quality.
  • Assess and quantify currently applied technologies to produce drinking water at a small scale level. Its integration with different solutions to address water shortage will be considered.
  • Adapt and develop a set of solutions based on technological components for water treatment on a small scale according to the end-users needs in the identified areas. These technologies will include:
    • Ultrafiltration with optimized energy demand
    • Filtration based on microfibers
    • Desalinization technologies such as reverse osmosis
    • UV disinfection
    • Membrane distillation
    • Adsorption using conventional and novel low-cost, locally available materials
  • Assess and quantify existing technologies for water quality monitoring to evaluate the quality of raw and treated water, and also the composition of wastewater. Special attention will be given to pathogens, studying the quality of water by state-of-the-art methods such as Quantitative Microbial Risk Assessment within the framework of Water Cycle Safety Plans based on good-house keeping.
  • Develop a Decision Support System which integrates multi-criteria evaluation of technological alternatives for obtaining drinking water of the appropriate quality in each socio-economic situation, together with its management and sustainability assessment. This DSS will allow stakeholders and authorities to compare and select the best components to meet environment, economic and social aspects.
  • Demonstrate the selected technologies in two pilot sites with different geological, hydrological and technical situations.
  • Propose best practice guidelines for the end-users, especially when small scale technologies are chosen.

CWS contribution to WATER4India

Led by Prof. Fayyaz Ali Memon, CWS team were primarily responsible for developing two tools:

  • A user friendly tool to reduce consumption at household level through the selection of water efficient technologies keeping in view a range of sustainability indicators and the Indian context
  • A high level decision support systems to propose a range of water treatment technology terrains and develop their multi criteria based evaluation with specific reference to application potential in developing countries.

This was a 3 year project supported by the European Union under the FP7 SME targeted Collaborative Project Call. The project team included nearly 20 partners from European Union member states and India.

Project partners

  • SOLINTEL M&P, Spain
  • University of Applied Sciences Northwestern Switzerland
  • Centre for Water Systems, University of Exeter, UK
  • RWTH Aachen University, Germany
  • KWR Water, Netherland
  • Cranfield University, UK
  • Adin Holdings, Israel
  • AMIAD, Israel
  • Solarspring, Germany
  • Vertech Group, France
  • Proinso, Spain
  • University of Technology, Sidney, Australia

View all of our projects related to our CWS research.