The move comes as a scheme led by the Environment Agency to reconnect the river Tamar with its original floodplain at Calstock has finished and the land leased, also for 20 years, to the Community Trust.
Hugh Tyler of Natural England said: “The project was only possible through a lot of support from local people, including TCT and partnerships with Tamar Valley AONB team, Cornwall Bird Preservation Society, Calstock Parish Council, and Cornwall Wildlife Trust and we’re all excited to see the changes that will take place here in the coming years.”
During the course of the next 20 years, the landscape will evolve from grazing land that had been created when the floodplain was cut off from the river by the building of an embankment around 200 years ago into the intertidal habitat. Since the embankment was breached 18 months ago, the land has begun to return to tidal wetland, and bird species including little egrets and avocet have been spotted using the site, as well as water rail, kingfisher, snipe, teal, green sandpiper and reed bunting.
Little land management will be needed on the 12-hectare site over the 20-year tenure, but it will ensure that no non-native invasive species, like Himalayan balsam, can take hold. Funding has also been put in place to allow for educational access so children can learn why this has been done.
Jane Kiely, Chair of TCT, said "We are so pleased that the importance of creating new tidal wetlands as part of Environment Agency flood protection works is recognised by DEFRA in this agreement. The breach in the older bank along the river was made just over a year ago and having the tide coming in twice a day has changed the site from one of low-quality compacted sheep pasture to a rich habitat of mud which is very popular with the water birds and waders. I also love seeing the wetlands full of water at high tide, the sun glinting, and the reflections of clouds and sky."
Rob Price, Tamar Catchment Coordinator at the Environment Agency, said: “The creation and management of new intertidal habitat on the Tamar at Calstock reinforces this partnership’s collective aims to improve resilience to the changing climate and to provide a richer environment for people and nature. It will provide an invaluable tool in the fight against climate change by locking in carbon, boosting biodiversity, helping improve overall water quality as well as providing a local amenity. 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.”
Management during the early years of Calstock Wetlands will respond to monitoring by TCT's partners, including Plymouth Marine Laboratory, Natural England, and Plymouth University looking at water quality, carbon sequestration, birds, plants, and fish.
TCT is also looking to improve the public experience from the public road or the permissive path that runs along the river bank, enabling both local residents and visitors to understand and appreciate what they are looking at.