The STREAM project aims to restore habitat in River Avon and Avon Valley for rare birds, plants and invertebrates. Details of how the project will help them are outlined below.

Water Crowfoot

River habitat

The typical River Avon plant community including water crowfoot and starwort has been damaged by a combination of factors including historic dredging and siltation.

STREAM river restoration will create more suitable habitat for the plant community by increasing flow speed and cleaning gravels.

Atlantic Salmon

Atlantic Salmon

The numbers of Atlantic salmon on the Avon are at a very low level, reflecting a national trend. The reasons include poor survival rates of adults whilst at sea and low breeding success due to lack of clean gravels. Salmon are also at risk of being trapped in the network of ditches and side channels in the Avon Valley.

STREAM will create suitable habitat for breeding and for young salmon and develop guidance on measures to reduce entrapment and facilitate fish passage.



Bullhead are present throughout the Avon system, but at in lower numbers than expected. A lack of fallen trees and logs (woody debris), and larger stones due to river management and past dredging means they have limited places to shelter and breed.

STREAM will improve habitat for bullhead by developing ways to introduce and retain woody debris.

Sea Lamprey


Sea lamprey are found on the lower Avon whilst Brook lamprey are found throughout most of the Avon system, both at lower densities than expected. Both need clean gravel for breeding and stable silt beds for the young to live in. Careful management of river margins and side channels and ditches is crucial for lamprey.

STREAM will contribute to the sensitive management of ditch networks and will provide spawning habitat for brook and sea lamprey.

Desmoulin's Whorl Snail

Desmoulin's whorl snail

The number of Desmoulin's whorl snail varies throughout the Avon system and is threatened by invasive plant species, reduction in wet river margins and inappropriate water level management.

STREAM river restoration will increase the availability of habitat for Desmoulin's and work with Living River to remove invasive plant species.



Gadwall are a scarce breeding bird and winter visitor to the Avon, inhabiting wet grassland, marshes and lakes with dense fringing vegetation. Most existing areas of habitat for this species are in poor condition due to inappropriate management and/or human disturbance.

STREAM will help to get more appropriate water level management in the Avon Valley and increase understanding if the effect of human disturbance.

Bewick's Swan

Bewick's Swan

Bewick's swans overwinter in the wet pastures, stillwater and floodplain grasslands of the Avon Valley. The wintering population is declining, in part due to inappropriate water level management and decline of traditional agricultural practices.

STREAM will help to get more appropriate water level management in the Avon Valley by developing hatch operating protocols and a ditch restoration programme.

Mending the Avon - restoration and management to help wonderful wildlife

Demonstrating STrategic REstoration And Management (STREAM) is a £1 million four-year conservation project centred on the River Avon and the Avon Valley in Wiltshire and Hampshire. STREAM will address two key issues: the need for a strategic approach to large-scale river restoration, and the need to integrate the management of the river and valley.

The STREAM project is supported financially by the European Commission's LIFE Nature programme. It is part of a broader initiative that encompasses restoration of designated sites, wider biodiversity work and a programme of community engagement.

Layman's report

Layman's report (PDF 2.5 MB)

Quick links

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