Flanshaw Beck Integrated Catchment Modelling, England
- Alastair Sheppard
- Dec 6, 2023
- 2 min read
What our customers say:
“The 1D urban solver proved to be an extremely powerful solution for evaluating the impact of extreme storm events on sewer systems, particularly when linked to the 2D solver to model the resulting surface flows and possible flood scenarios for the area of interest.”
Flood Modeller was instrumental in understanding the flooding mechanisms involving overland flow from an open channel and the subsequent overflowing of the sewer system in a small and heavily urbanised catchment.
The steep and urbanised catchment in West Yorkshire, England, ranges from 30 to 91m AOD in elevation and covers 0.9km². A small ordinary watercourse flows easterly through the area of interest, with the majority of its 940m reach culverted, except for a short section of open channel before re-entering a culvert prior to its confluence with another watercourse.
With the frequency and severity of floods increasing alongside rapid urban development, there is growing pressure to protect urban areas from flooding and preserve water quality.
Historically, flood modelling often only considered the impact from river systems, leading to a misrepresentation of flood risk by not assessing the interdependence of surface and subsurface flows. An integrated catchment management approach is essential for planning and designing sustainable solutions to prevent flood risk.
Overland flow from Flanshaw Beck and surcharges from manholes have caused surface flooding in several properties within the catchment. Understanding the flooding mechanisms affecting properties and roads in this small but heavily urbanised area was crucial.
Key Facts
Detailed flooding mechanisms: Accurately represented overland flow and manhole surcharge scenarios.
Superior simulation speed: Flood Modeller's simulations were up to 49% faster than alternative software.
Stable and reliable: Maintained numerical stability throughout the simulation process.
Integrated GIS capabilities: Flood Modeller’s GIS interface, toolbox, and pre- and post-processing features eliminated the need for third-party software.
Flood Modeller offers an easy-to-use, fast, and cost-effective solution for fully integrated catchment modelling. It utilises Flood Modeller’s 1D river solver to model channels, its 2D solver to model overland flow across floodplains, and the 1D urban solver to model sewer networks.
In this study, Flood Modeller’s 1D urban solver was dynamically linked to its 2D solver, leveraging the software's speed, stability, and accuracy. Its intuitive GIS-like interface provided a wide range of model-building tools, as well as pre- and post-processing capabilities, eliminating the need for third-party GIS software.
Tools such as the Damage Calculator quickly assessed the overall economic impact of flooding, providing a better understanding of the severity of flood events and calculating the damage for each affected property.
An initial test phase determined the most appropriate software for this project, revealing that Flood Modeller enabled each simulation to run up to 49% faster compared to other available software. The results were not sensitive to timestep selection and closely reflected the flood mechanisms at the study location, maintaining numerical stability throughout the simulation.
The 1D urban solver proved to be an extremely powerful solution for evaluating the impact of extreme storm events on sewer systems, particularly when linked to the 2D solver to model the resulting surface flows and possible flood scenarios for the area of interest.
