Flood Defence Wall, River Deben Woodbridge

Site inspection and ecological support for the Woodbridge flood defence wall on the River Deben.


Client: Environment Agency

Services: Buildings, Advisory & Planning

Main Contractor: JacksonHyder

Value: £900,000


Sweco were appointed under the Environment Agency’s WEM framework to undertake a site inspection to investigate the adequacy of the Woodbridge flood defence wall on the River Deben.


The initial investigation into the sheet pile flood wall included a visual investigation, a ground investigation using window samplers, reviews of record drawings and a structural analysis using flood modelling data provided by the Environment Agency. A sensitivity analysis was undertaken and a report produced informing the client of the stability of the flood defence and several design options presented to remediate the asset.

The detailed design was developed in conjunction with the main contractor to ensure a buildable, economic solution was reached. A retaining wall supported by mini piles was designed to minimise the amount of material required and allow for construction to occur on the limited access site on poor ground conditions.

Our ecology team provided support to ensure works complied with all relevant wildlife legislation. We supplied a precautionary method statement and supervising ecologist to facilitate the works and minimise the risk to reptiles in the most appropriate, cost effective method.


  • Use of Comfrey™ concrete to reduce carbon footprint of works
  • Liaison with Environment Agency, the contractor, and local stakeholders