Linking river & valley
The management of the lower River Avon is intimately linked with the management of the grazing marshes of the Avon Valley. The breeding waders and wintering birds that use the valley are dependent on suitable conditions being created by controlling and retaining water on the floodplain at key times. Conditions for them in the SPA are currently unfavourable, largely due to neglect of the watercourse network and inappropriate water level management.
To restore favourable condition will require rehabilitation of the ditch network, tree and scrub removal and restoration or installation of sluices or structures. However, all these activities potentially affect fish populations, including Atlantic salmon, lamprey and bullhead. Active water level management on the floodplain can trap fish, and affect upstream and downstream migration routes by the installation of barriers, alterations of habitat, temperature and flow regime
Currently, to protect SAC fish populations, a precautionary approach has been adopted in assessing proposed SPA restoration works. Whilst protecting the fishery interests, this is impeding actions to restore the valley.
The STREAM project will help to overcome these conflicts and contribute to both the integrated management of water levels in the Valley, and the needs of migrating fish populations in the River Avon by;
- Identifying ways to stop fish species getting trapped in the valley ditch networks
- Developing a strategic programme of ditch restoration
- Developing and trialling operating regimes for key sluices in the river and valley
- Sharing best practice with landowners and feeding into the Environment Agency's Water Level Management Plans
Methods to prevent fish entrapment
In order to improve the status of the Avon Valley SPA without impacting upon the River Avon SAC fish population interests, there is a need to identify methods and the associated costs by which fish can be excluded, or migration facilitated, when water is diverted and/or retained within the floodplain channel network.
A study was commissioned to review existing and new methods of fish exclusion which are low maintenance and cost-effective. The results will be used to inform landowners and river managers of best practice for excluding or facilitating fish movement from ditches within the SAC and SPA where appropriate. A seminar in which the results will be discussed with landowners will be held.
Strategic programme of ditch restoration
A strategic methodology and assessment of the ditch network is required to inform the programme of works to restore the Avon Valley SPA and River Avon SAC and guide the selection of sites for further floodplain restoration (including implementation of Water Level Management Plans on the Avon System).
The ultimate objective is to produce a map based plan for use by agencies and land managers that sets priorities for watercourses within the Avon Valley SPA. This will identify watercourses that are:
- key to restoration of favourable condition within the SPA, without detrimental fishery impact
- where wetland restoration can accommodate or enhance fishery interests
- of particular importance for SAC fish species.
- of particular importance to other, non-SAC fish species.
The work initially focussed on developing the methodology in one study area just north of Ringwood. Outputs from this project will then be subsequently used to evaluate rest of the Avon SPA & SAC. A seminar in which the results will be discussed with landowners will be held in 2007.
The studies to prevent fish entrapment and develop a strategic programme ditch restoration are complete and available to download:
Linking river and valley (PDF 3.1 MB)Hatch operating protocol
Protocols will be developed to help co-ordination and co-operation between hatch operators and reduce potential conflicts between different interests. A study of key structures on the River Avon will clarify their role in managing water levels, and to explore cost-effective options for their maintenance or replacement with alternative structures or systems of water level management where required. A seminar in which the results will be discussed with landowners will be held.