Ground-breaking River Avon wetland restoration completed

A ground-breaking river restoration project on an area of wetland in West Chisenbury, near Upavon, has been completed.

The work, funded by the Defence Infrastructure Organisation (DIO), has enhanced the biodiversity of the local area by improving the watercourse and natural floodplain, and off-setting nutrient pollution.

Secondary channels connecting wetlands and ponds have also been created, help establish wildlife habitats across the river’s floodplain.

There are also environmental benefits, as the new wetland areas will help capture nutrient-loaded sediment and carbon.

The river Avon is considered one of the UK’s finest chalk streams and is a Site of Special Scientific Interest as well as a Special Area for Conservation.

Chalk stream ecosystems are vulnerable to nutrient pollution. Increased amounts of nutrients, such as phosphorus, in rivers can cause increased growth of algae and large aquatic plants. This results in decreased levels of dissolved oxygen, which can kill fish and other aquatic life.

In restoring 400-metres of river, wetland habitats will now retain water all year round, meaning native plants and wildlife can thrive.

Many species found locally will benefit from the improvements, including water voles, dragonflies and damselflies.

Fish such as wild brown trout will also be able to spawn thanks to the environments created by re-profiled gravel ‘riffles’ - shallow sections of river where water flows more quickly.

Jenny Bennet, Senior Ecologist, Defence Infrastructure Organisation, said:

“The MOD is committed to supporting nature recovery at the national and local level, while at the same time supporting and enhancing military capability. We aim to be a leader in wildlife and nature conservation and to achieve this, DIO funds a rolling programme of conservation projects across the UK and overseas Defence estate.

“This innovative project, delivered in partnership with Wiltshire Wildlife Trust, will bring long-term benefits for biodiversity as well as directly addressing the issue of harmful nutrient levels, one of the key pressures affecting our rivers. We look forward to witnessing the new wetland evolve over the next few years.”

Alice Eley, Water Team Manager for Wiltshire Wildlife Trust, said:

“We’ve been excited to work with the MOD on this pilot project, which we hope will inform future projects to improve the health of our chalk streams using natural solutions.

“As well as capturing harmful nutrients like phosphorus and improving biodiversity in the area, the more natural shape and size of the river channel should also kick-start natural river processes such as sedimentation in the margins and faster flows in the main channel to promote weed growth and create clean, spawning gravels.”