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The Centre for Water systems is committed to the practical application of its work. For example, the CWS sewer deterioration modelling tool based on a novel data-mining approach, evolutionary polynomial regression (EPR), has been validated through an industry funded project (UKWIR). The tool has recently been used to model clean and wastewater asset deterioration at Anglian Water (in collaboration with Mouchel), to model the natural rate of rise in leakage at a UK water company (in collaboration with RPS Group), and to model discolouration risk at another UK water company.

Our optimisation software and expertise has been used in practical applications such as to tackle the operational management of the water supply system in Moravia (Czech Republic) in association with the DHI-Hydroinform.

Our work on spatial ordered weight averaging in decision-making is used as a training resource by the GIS software company ESRI, and was awarded the 2006 best paper award by the Environmental Software and Modelling journal.

GANetXL is an optimisation add-in for Microsoft Excel®. GANetXL uses genetic algorithms to solve complex optimisation and search problems. The application offers a user friendly interface to set up the optimisation problem and configure the algorithm. Unlike many other commercial products GANetXL allows solving single and multiple-objective optimisation problems. The software is provided FREE of charge for academic non-commercial research and has been used by a number of users worldwide. 

How to cite GANetXL work

If you are using GANetXL and writing a conference/journal paper or report, please use the following citation to refer to the paper describing the software:


To obtain a trial serial number for GANetXL valid for 3 months please complete the following registration form. Current users who wish to renew their licence to obtain a free 1 year academic licence that can be renewed annually or require different licence parameters need to contact Prof Albert Chen since the registration form cannot handle such requests at the moment.

A special version of GANetXL that can be installed on any computer witout the need to obtain a HW identifier can be provided for teaching purposes. Please contact Prof Albert Chen with further details in order to get the copy.


  • Single and multiple-objective optimisation techniques
  • Support for integration with simulation packages
  • Suspend, resume and browse optimisation interactively
  • Multiple-objective results browser
  • Batch runs
  • User defined constraints & penalty multipliers
  • Automatic saving of population
  • Backups of intermediate population
  • Graphical UI
  • Visualisation of results and progress


  • User manual - A user manual providing details about how to install and work with GANetXL.
  • GANetXL presentation - A presentation showing how to setup and solve a simple optimisation problem using GANetXL.
  • GANetXL - - GANetXL is a Genetic Algorithms add-in for Microsoft Excel® supporting single and multi-objective optimisation. GANetXL is available for free for non-commercial academic use.
  • GANetXL examples - Environmental Modelling & Software Examples 


Support of the GANetXL addin is provided by the community of GANetXL's users on Linkedin. Please, consider joining our Linkedin group and share your experience with GANetXL with other people interested in single- and multi-objective optimisation using evolutionary algorithms.

Bugs and problems you encounter while working with GANetXL can also be reported to Prof Albert Chen

Commercial Application

GANetXL is strictly provided for FREE only for non-commercial academic research. Commercial users are however welcome to try SolveXL, which apart from offering the same functionality like GANetXL, provides several additional features and can be licensed for commercial use.

Community contributions


The new Evolutionary Computing methodology for multiobjective optimization of water distribution system design, GALAXY (Genetically Adaptive Leaping Algorithm for approXimation and diversitY), has been used on a number of benchmarks available on this site. GALAXY was developed as part of the PhD work by Dr Qi Wang.

This was developed into a paper: Wang, Q., D. A. Savić, and Z. Kapelan (2017), GALAXY: A New Hybrid MOEA for the Optimal Design of Water Distribution Systems, Water Resour. Res., doi:10.1002/2016WR019854. The paper is available to view on our website.

The code for the GALAXY algorithm and the brief tutorial can be downloaded from here: GALAXY

CWSNet is an open-source library for water distribution system modelling where all the various parts of the hydraulic model are completely developed in C++ using an object-oriented programming (OOP) model. The aim is to develop a library that can be easily extended while providing high computational performance.

The idea behind this software is to simplify development and testing of new hydraulic elements (specific types of valves, pumps, etc) and computational algorithms (pressure-driven approaches, etc.) by keeping logically independent parts of the code separate. This also allows the performance and accuracy of new computational methods as well as the use of advanced programming techniques to be studied without the need for extensive code refactoring.

Aims and features

Highly expandable:

  • Written in C++ using the object-oriented programming model (OOP).
  • The internal structure of the library is divided in three layers:
    • Network layer.
    • Hydraulic solver layer.
    • Mathematical layer.
  • Use of linear algebraic operations: implementation of new computational methodologies is easy, for example, adding a new hydraulic solver.
  • Able to apply several simulation engines (implementations of a hydraulic solver, water quality analysis etc) to the same model and combine them into an EPS.
  • The outputs of an EPS can be substantially customized.

High performance:

  • Runs different simulations of the same network or different networks in parallel (thread-safe).
  • Able to change the linear solver and the matrix representation used to solve the system of linear equations.
  • Ready to use with OpenMP, GPGPU (CUDA) and Vectorisation.

EPANET2 compatibility:

  • Reads EPANET2 input files.
  • Contains a Demand-Driven Global Gradient Algorithm (GGA) solver.
  • Produces comparable hydraulic solutions for a number of publicly available networks.

Widely used:

  • Open source - MIT License.
  • Runs on multiple OS and compile on multiple compilers:
  • Windows - Visual Studio C++ 2008/2010.
  • Linux - GCC.

Plenty of documentation available:

  • A guide to the installation, use and development of the library in Wiki format.
  • The API documentation automatically generated from the source code using Doxygen.
  • A ticket system publically available that can be used for reports of bugs and task requests.

Useful links


CADDIES is an open-source framework which aims to use Cellular Automata (CA) techniques and modern hardware with parallel processing capabilities for fast dual-drainage flood modelling (2D urban surface flows linked with 1D subsurface sewer flows). CADDIES includes a general purpose CA Application Programming Interface (API), which allows users to write their own CA rules, which can then be deployed on a number of different hardware platforms, and/or on a number of different CA types.

The CADDIES framework is divided into multiple components / softwares:

  • An application programming interface (API) to create cellular automata rules and associated application(s).

  • A set of different hardware platform implementations for each CA type, allow for fast deployment of rules to highly parallel hardware, including (Linux and Windows variants of):
    • Simple serial implementations.
    • Shared memory model parallel implementations on modern CPU's, using OpenMP.
    • General Purpose Graphics Processing Unit (GPGPU) highly parallel implementations, using OpenCL.

  • A set of different CA type implementations, including:
    • Regular square grids
    • Von Neumann Neighbourhood.
    • Moore Neighbourhood.

  • Regular Hexagonal grids (under development).
  • Rapid and accurate reduced-complexity 2D urban surface flow model(s).
  • Basic application, and CA rules - Open Source
  • Advanced application and CA rules - under license agreement
  • Application
  • Dynamic Link Library (DLL) API flooding interface (under development)
  • Rapid and accurate reduced-complexity 1D sewer flow model(s) (under development).
  • Unified 1D sewer and 2D surface flow model(s) (under development).

>> Find out more information about the Caddies Framework

A tool for global resilience analysis of water distribution systems can be downloaded: GRA Tool

This is a simple, user-friendly tool that automates the simulations required for GRA of a water distribution system and assists comprehension of the results. Provided the user can supply an Epanet .inp file for the system and that this contains demand data (an understanding of Epanet and system failure modelling is not necessary), the tool can be used to quantify the resilience of the system to pipe failure, pump failure, demand increase and contaminant intrusion. An interactive results explorer allows the user to easily identify critical system components based on the selected level of service type and failure measure (e.g. pressure, supply or contamination and failure magnitude or duration). A map of the network can be used to either color-code components based on their criticality in a single component failure analysis or to identify specific combinations of components which result in the greatest level of service failure magnitude or duration when failed simultaneously. ‘Stress-strain’ type response curves can also be automatically generated and key findings automatically extracted. Additionally, the tool enables systems to be compared on a like-for-like basis, enabling the effects of proposed interventions on resilience to be quantified and visualized.

Please reference the tool as follows:

Diao, K., Sweetapple, C., Farmani, R., Fu, G., Ward, S. & Butler, D. (2018) Global resilience analysis of water distribution systems. Water Research, 106, 383-393.

Sweetapple, C., Diao, K., Farmani, R., Fu, G. & Butler, D. (2018). A tool for global resilience analysis of water distribution systems. 1st International WDSA/CCWI Joint Conference, Kingston, Ontario, Canada, July 23-25, 2018.

PST is a model-driven decision-support system tool for pump operation scheduling in water systems. The PST is a dynamic tool which has been developed as an Excel-add-in. It can handle four different kinds of schedule representation including On and Off, Time control, Time-length control and Tank water level control. The PST has the ability to integrate a multi-objective (MO) evolutionary optimization package with an external hydraulic (e.g. EPAENT) to obtain an optimum schedule. The tool has a user-friendly interface which allows simulation based on three pump operation settings: 1) hydraulic model’s input file, 2) interactive interface which can be modified by the user, and 3) generated by the optimization algorithm. It also has an intuitive interactive results interface to present and visualize the produced solutions. The user defined options allow the user to solve a problem either as two objectives optimization or as a single objective optimization.


A step-by-step tutorial as well as PST for both 32-bit and 64-bit operation systems can be downloaded: Pump Scheduling Tool.

Users who may encounter problems whilst working with PST can report any problems to Karwan Muhammed.

FaME-DST is a decision support tool for the selection of optimal wastewater treatment technologies for the removal of conventional and emerging contaminants and to identify optimal solutions for sludge management, nutrient recovery and energy recovery. This piece of software has been developed as part of a project called: Fate and Management of Emerging contaminants (FaME) at the Centre for Water Systems (CWS), University of Exeter and is now available for public access. The FaME Project has been funded by the Natural Environment Research Council (NERC), UK and Department of Science & Technology (DST) and the Government of India.

Led by Prof Fayyaz Ali Memon, the FAME team includes key academics Prof David Butler and Prof Shaowei Zhang from the University of Exeter, Dr Sarah Bell from UCL (now the University of Melbourne), Professor Ligy Philip (IIT-Madras), Prof Absar Kazmi and Dr Bhanu Prakash Vellanki (IIT Roorkee). Dr Seyed Sadr was the main developer of FaME-DST.


If you would like to download the tool, please complete the following registration form