The stretch of the tidal River Tamar that was converted to farmland in 1850 when an enclosing embankment was built, will now become part of the original flood plain as the conservation charity breaches the bank to allow the tide to flood in.
The new 1.7 hectare intertidal habitat has been created thanks to a £250,000 partnership project with the Environment Agency and supported by Natural England and Plymouth University.
The work forms part of a larger programme of habitat creation and improvement throughout the Tamar catchment which aims to create new intertidal habitat which will improve resilience to the changing climate and to provide a richer environment for people and nature.
It will also provide an invaluable tool in the fight against climate change by locking in carbon, clean river water by trapping sediment and provide more space for water during high tides or heavy rains.
The work will also alleviate flooding at Cotehele Quay car park which is one of several areas along the river subject to regular flooding during high tides and stormy or windy weather.
Alastair Cameron, project manager at the National Trust, said: “By creating new wetland habitat similar to that found before the embankment was built, we can make space for nature and water.
“This month we’ve made a relatively small breach in the bank and now we’ll let nature and the tides take their course. It’s really exciting to see the water flowing in now with the spring tides.”
The new naturally created habitats at Cotehele will, over the next five-10 years start to attract a wide range of wildlife including worms and other invertebrates, and wetland birds including shelduck, redshank, curlew and little egret. The open water area will attract ducks such as wigeon and teal, and the new habitat could also attract smaller creatures such as otters and harvest mouse.
Alastair continued: “Over the coming years we’ll start to see changes in the habitat which should attract typical Tamar estuary species and in time we’ll see more permanent intertidal vegetation increase like reeds which will attract more and different wildlife.”
The first phase of the project which was completed in April this year created channels to allow water to move and flow easily into the new wetlands. An embankment was also built to form the boundary at the one end of the new intertidal habitat to protect existing infrastructure.
Tony Flux, coast and marine adviser in the South West for the National Trust, commented: “This project is a good example of our ‘Shifting Shores’ coastal management principles for working on the coast and in tidal estuaries.
“Working with nature rather than against it is a more sustainable and long-term solution – and is much less costly than a continual cycle of build and repair, which will only increase in frequency as our climate changes. To continue to repair the old embankment would have been a never-ending task.
“The work we are doing will enable the river to behave much more naturally and adapt to the changes happening at our coastal and estuarine areas, which are invariably the first places to feel the impacts of climate change.”
“It will be fascinating to be able to closely watch as a new inter-tidal habitat evolves over the next few years”
Rob Price, catchment coordinator for the Environment Agency, said: “The breach of the bank at Cotehele is an exciting milestone for this partnership project and the Tamar Catchment.
“We are very much looking forward to see the new inter tidal habitat establish over the next few years as the project now turns its focus to monitoring the benefits that this enhanced area will provide for local wildlife, habitats and people.
“This valuable work is an important part of an integrated programme of works to build the Tamar Catchment’s resilience to a wide range of environmental pressures including those related to Climate Change.”
The project is being funded by the Environment Agency Water Environment Investment Fund and the National Trust’s own Neptune Coastline Campaign – which raises money specifically for coastal projects.