Project overview

Hydrology is a foundational component of flood modelling. However, current approaches in widespread use were not designed for the challenges we face today and of those in the future. With flood management schemes also becoming more complex, and reflecting these challenges, we need to add new approaches to the way we do flood hydrology to make sure we always have the right tool for the job.

This project is focussed on identifying appropriate new methods where they already exist, for example as research methods, and learning how to overcome the barriers in getting them more widely adopted for decision-making. It is a long-term approach, with the initial phase being delivered as part of the Flood Hydrology Improvements Programme.

Continuous Simulation is an approach to flood hydrology that is more appropriate for complex projects than the more frequently used approaches. Instead of relying on a single design hydrograph, it uses a long timeseries of modelled rainfall to simulate river flows using a rainfall-runoff model. This provides a lot more information and detail about the frequency and magnitudes of possible floods to those making decisions.

This approach has been available for use operationally for over two decades yet only a small fraction of flood studies have adopted it in that time. As it is more complex and requires more money and time to undertake, there are many barriers that have to be overcome – decision-makers are less well informed about the approach, there is less availability of skilled practitioners able to carry it out, and there is less support and dedicated tools to support its use.

The phase 1 of the EAM7 project will take actions to overcome some of these barriers as they exist internally in the Environment Agency and our equivalents in Scotland, Wales, and Northern Ireland.

• Map a workflow for the continuous simulation approach, signposting to useful datasets and methods, and suggesting ways to characterise uncertainty and incorporate climate change.
• Co-produce continuous simulation awareness and training materials with internal colleagues who commission and review flood studies.
• Produce a ‘tech radar’ to horizon scan for possible future flood hydrology methods and assess their feasibility for operational use.
• Plan the second phase of the project, including requirement to support continuous simulation externally.

How our project is improving flood hydrology:

• The workflow and training materials will improve awareness of continuous simulation amongst those who commission flood studies and build their confidence and agency to request the approach.
• It will increase the diversity of approaches available for flood hydrology, improving the reliability and robustness of flood modelling, especially for complex schemes.
• It will highlight a way forward to making further improvements around methods, supporting the use of the benchmarking system being created by EAM4.