- On 26th January 2018
- In Ecology, Engineering, Sediment Management
- By William Coulet
As part of the Brightlingsea Harbour Commissioners (BHC) four year dredging and restoration project supported by the Interreg 2 Seas initiative, ‘Using Sediment As a Resource (USAR)’, Exo and harbour staff have been busy out on our floating pontoon system and working across the intertidal mudflat installing the brushwood fascine retaining structures in preparation for the placement of arising dredged material.
The compartments created will retain the newly placed material during the dewatering and consolidation process whilst the sediment remains vulnerable to erosive forces prior biological colonisation and subsequent succession. The positioning of these structures is based on a number of factors ranging over varying temporal and spatial scale, including, but not limited to; existing bed and target elevations, historic aerial analysis and geomorphic features such as drainage rills and their natural meandering across the adjacent mudflat.
Our most recent work has the additional target of protecting existing coastal flood defences surrounding Howland’s Marsh Nature Reserve, 74ha of some of the best surviving coastal grazing marshes in Essex. Due to continued erosion of the fringing saltmarsh in the area, the flood wall has become exposed in a number of places. Continuing previous habitat creation efforts on behalf of the Essex Wildlife Trust, these works and the subsequent placement and colonisation of arising dredged material, aim to restore this saltmarsh habitat whilst simultaneously offering toe protection and improving the stability of the flood wall through improved ecosystem functioning and services.