2023
Beneficial use of dredged sediment
United Kingdom
Chichester Harbour
-0.87459683
50.807942
Saltmarsh
0.02 Hectares
Biodiversity Enhancement
Demonstration or Pilot Project
Habitat Enhancement
Improve Water Quality
This project was undertaken for three main reasons.
1) Enhance an area of deteriorated saltmarsh in Chichester harbour;
2) Test a new way of beneficially using dredge sediment developed by Land and Water Services Ltd.; and
3) Measure the nitrate absorption of saltmarsh as part of a wider nutrient neutrality programme being undertaken by Earth Change, CEH and Bangor University.
The new technique involved a process of firstly depositing sediment on the low shore directly from a spilt hopper barge and then moving it to the saltmarsh zone at the top of the shore using a new 'drag box'. This new drag box was designed, built and implemented by Land and Water Services Ltd.
This drag box approach introduces a novel and potentially very valuable way of using relatively consolidated dredged sediment for saltmarsh habitat restoration. Its value lies in the fact that it can place dredge sediment directly onto marsh levels and keep it there without the need for introducing retaining fences and without affecting the productivity (turnaround and cost) of the dredging operations.
This project was part of the Solent Seascape Project and was supported and informed by several partners including the Chichester Harbour Conservancy and CHaPRoN (see link below).
Monitoring is being undertaken at this site to understand how the area performs. The lessons learned will be captured and shared to understand how widely this approach can be applied.