Hydrology & Hydraulic Modelling
Keywords: Surface Water Management Plan and Options development, including SUDS (TUFLOW)
Cambridge City and Cambridge County Council
Edenvale Young in conjunction with Hyder Consulting were appointed to undertake the Cambridgeshire Surface Water Management Plan. The scope of work includes preparation of:
Preliminary Flood Risk Assessment (PFRA) for Cambridgeshire
Phase 1 Countywide SWMP assessment
Phase 2 and 3 SWMP assessments for the Cambridge and Milton
Since the inception of the project we have been developing a detailed TUFLOW model which has iteratively incorporated increasing levels of detail within Cambridge. From an initial high level, to a now detailed modelling of the surface water system, we have progressively refined our modelling to improve model detail, while ensure a 'best value' approach.
Scope of Work
As part of the project Edenvale Young has developed a preliminary 2D TUFLOW model of Cambridge based upon LiDAR information. Direct rainfall was applied to a bare earth model for a range of storm durations and return periods in order to verify the model against FEH estimates of flow on the Bin and Vicarís Brook in north and south Cambridge respectively. This exercise included sensitivity testing to be undertaken on storage / infiltration losses on the catchments. The geology to the east and south of the Cam was particularly interesting having a high permeability commensurate with the underlying limestone deposits. The modelling included:
Inclusion of varying ground roughness across the model domain which takes account of roads, parkland and buildings.
Sewer assets, watercourses, culverts and other assets affecting flooding.
Innovation of WebGIS
The SWMP for Cambridge has provided the perfect opportunity to further develop and utilise our WebGIS tool. This tool can map flooding from a number of sources including historical, modelled and user defined outputs to create a synthesized record of flooding. Included in the sytsem is a tool for generating a multi criteria score and also assessing damages. This means that it is an invaluable resource for Local Authorities and Councils who are required to undertake PFRAs. For more information on the WebGIS please click here