Background
The Environment Agency’s national strategy for Flood and Coastal Erosion Risk Management (FCERM) has an overarching principle of moving away from the narrow concept of protection to a broader one of resilience.
However, there will inevitably be locations where hard defences continue to be required to manage the risks of flooding and coastal erosion. Wherever possible, future investment in these types of defences should aim to deliver multi-functional benefits, such as increasing biodiversity and reducing carbon. Therefore, there is a need to re-think how traditional rock and concrete defences are designed and constructed.
One nature-based solution is to use low-carbon concrete units which are designed to function as habitat for marine life, as well as coastal armour. Such products have been developed, using materials that match the natural pH of seawater and incorporate features that replicate habitat, such as rockpools and the crevices found in shoreline rock.
It is envisaged that these ‘eco-blocks’ can be used in future FCERM schemes to construct defences such as breakwaters. At present, there is a need to trial the products in a high wave energy environment to determine which habitat features and block properties are best suited to this type of location.
Project details
This is a research and development project that will investigate the use of eco-blocks as a potential material to be used in future FCERM schemes. Specifically, the project will monitor the eco-block’s ability to enhance biodiversity and withstand a high-energy environment, as well as the effect of block size and orientation. The project will not seek to reduce flood or coastal erosion risk.
The eco-blocks will be deployed on and around the existing rock armour breakwater at Newlyn in south west Cornwall, and the findings will feed directly back into future projects within Mount’s Bay and elsewhere to maximise multi-functional benefits associated with managing coastal change. The work is part-funded by EU Interreg under the SARCC (Sustainable and Resilient Coastal Cities) project.
What work has been carried out so far?
As part of a preliminary phase of the project, the Environment Agency has been monitoring a trial of small-scale eco-blocks placed on the landward side of Newlyn breakwater, at the mouth of the Newlyn Coombe River. After a year in position, these blocks are showing encouraging signs of colonisation by marine life.
A small, trial eco-block, 9 months after being deployed
What happens next?
The Environment Agency and partners are currently working to select the preferred type of eco-block that will be used and the optimum placement to maximise learning outcomes. The necessary permissions required are also being sought to carry out the work, including a licence from the Marine Management Organisation (MMO).
Deployment of the eco-blocks at Newlyn is currently programmed for late summer 2022 and is expected to last for approximately 6-8 weeks. This will include setting up a site compound to store plant and materials on Newlyn Green, whilst the eco-blocks themselves will be transported to the breakwater along the beach front.
We are working with Cornwall Council to minimise community disruption and will provide further details nearer the time. The area of Newlyn Green used for the site compound will be reinstated upon completion.
Regular monitoring of the eco-blocks will begin immediately following their deployment according to a monitoring plan that is currently in development.
Timescales
- February 2022: public drop in event to explain more about the project and take questions
- mid to late summer 2022: installation of eco-blocks around the existing rock armour breakwater at the mouth of Newlyn Coombe River, expected to take 6-8 weeks
- post-construction: ongoing monitoring of project
If you would like further details about the Newlyn coastal research and development project, please contact Stephen Bentall, the Environment Agency’s Project Manager via the Devon, Cornwall and Isles of Scilly enquiries team: [email protected] or call 020847 47914.
