Hydrodynamic modelling

Herrington Consulting has developed the use of TUFLOW hydrodynamic modelling software for use in predicting the impact of breach, overtopping and overflow scenarios in both urban and rural areas. This information is then used to inform the Flood Risk Assessment (FRA) process to ensure that our appraisals are fully compliant with Planning Policy and provide the most accurate assessment of flood risk.

Generally the starting point of the FRA is the Environment Agency's/SEPA’s Flood Zone maps, which give an indication to the extent of flooding. However, this mapping does not take in to consideration the presence of any flood defence infrastructure. Therefore, in cases where flood defences do exist, a true representation of flood risk is not given and as such development potential is often curtailed.

TUFLOW provides the ability to overcome this by simulating the propagation of floodwater across a detailed model terrain that can include a range of features that influence the flow of water such as buildings, underpasses, bridges etc. This allows a more realistic representation of flood risk as well as enabling a range of flood flow simulations to be developed. These include;

To enable the risk of flooding to be quantified, both within a wider study area and at a site-specific scale, the TUFLOW model can be interrogated at selected points to provide detailed flood depth and velocity information. In addition, data such as water level, unit flow vectors, energy level, flood hazard and Froude numbers can also be extracted.