Provision of hydrological, hydraulic and flood risk services
Hydro-Logic has been engaged since 2002 on a series of investigations for Hanson Aggregates throughout England. The majority of these investigations relate to proposed sand and gravel extraction in flood prone areas. Additional investigations have been undertaken for monitoring and consent compliance.
The typical scope of works for FRAs (Flood Risk Assessments) is dictated by the flood zone in which the proposed development is located and the requirements of relevant planning legislation, including PPS25. A Level 2 FRA, for example, has been completed for the last phase of the Cassington Quarry and the proposed Eynsham Quarry developments to the west of Oxford.
More detailed Level 3 Assessments have been undertaken for sites adjacent to the River Thames in Oxford and the River Nene in Northamptonshire. The Level 3 assessments involve the use of hydraulic models to assist with estimation of flood levels across sites. The models can then be used to investigate the impacts of the proposed quarry development and restoration phases on flood water levels. Most quarry development involves the creation of temporary soil storage bunds, and it is particularly important to demonstrate that any impacts on flood risk are acceptable and manageable throughout the lifetime of the development.
In execution of these projects, we have worked closely with other specialists appointed by Hanson. We have also worked closely with the planning and regulatory authorities, including the Environment Agency, to streamline the planning process.
FRA: Quarrying case study