Project Description


Water Resources Group UK


Every 5 years, water companies in England and Wales must formally update their strategic water resources management plan (WRMP) which forecasts how demand will be met or managed over the next 25 years.

Regional planning aims to identify the most efficient and effective way to share new water resources, while maintaining security of supply, protecting the environment and minimising costs to customers.


With challenges around auditability, speed of convergence, flexibility and the many hours and even days, the existing model was taking to deliver, we were approached to provide recommendations around best practice and optimisation modelling software.


We found that the existing Mixed Integer Linear Program was entirely suitable, however, the overall system was implemented on inappropriate spreadsheet based software platform and an insufficiently powerful solver.


We recommended the use of multi-dimensional modelling platform AIMMS for a succinct representation of the mathematical model, together with interactive and visual user views to aid sense checking and interpretation of results.

We also recommended the use of the Cplex solver, which has an excellent track record for fast solution of large and complex integer linear programs.

We used these to develop the OPTI-WRMP model and carried out a pilot study on a region characterised by multiple water resource zones, interzonal transfers, and complex interdependencies.

The new model is able to represent an extremely large and complex set of water resources options. It can quickly identify an optimal strategic plan to balance project supply and demand across a range of 10, 25 and 50 year planning scenarios. It has also delivered a reduction in solution times from more than 24 hours to less than 10 minutes.


Based on the pilot, decisionLab is involved in the development of the regional model for the next round of strategic water resources planning and our problem solvers are on the Peer Review team for this cutting-edge project.