River Teme Case Study

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PROJECT | Background Our geomorphologists, ecologists and fisheries experts developed a river restoration plan for the River Teme, a tributary of the River Severn which passes through Herefordshire, Shropshire and Worcestershire, with its headwaters in the Welsh borders. Natural England’s vision for the River Teme is to return it to a more natural condition by restoring the natural form and function of the river and its floodplain over the next 50 years. A total of 134 km of the River Teme was designated as an SSSI in 1996, of this 110 km flows in England together with approximately 5 km of the River Clun and this combined river length forms the study area for this project. The Rivers Teme and Clun support important populations of otter, Atlantic salmon, bullhead, grayling, twaite shad, brook lamprey, sea lamprey, and white-clawed crayfish and the lower reaches of the River Clun are of European importance for the populations of freshwater pearl mussel. The existing condition of the Teme is influenced by physico- chemical, hydrological, biological and physical factors. The majority of the SSSI remains classified as ‘unfavourable recovering’ due primarily to physical system modification including: Weirs Mills Hydropower Bridges Deflectors Revetment Embankments Invasive species and disease The overall aim of the project was to address physical habitat issues and devise an appropriate whole river restoration plan to be implemented on the ground. The river restoration plan was based on a detailed scientific understanding of the river and floodplain and set out a means to which the recovery of the SSSI could be achieved in the long term. What we did? We conducted an integrated geomorphological analysis and ecological interpretation of physical impacts on the river. This involved auditing and surveying the complete length of the 130km river. The ecological survey recorded habitats adjacent to both banks of the river following the standard Phase 1 Habitat Survey methodology. River Teme Client, Stakeholders, Partners: Natural England Location: River Teme SSSI Date/Phase: 2013 Key: River Restoration Plan, Geomorphology, Ecology, Fisheries, Water Framework Directive

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Transcript of River Teme Case Study

PROJECT | BackgroundOur geomorphologists, ecologists and fisheries experts developed a river restoration plan for the River Teme, a tributary of the River Severn which passes through Herefordshire, Shropshire and Worcestershire, with its headwaters in the Welsh borders.

Natural England’s vision for the River Teme is to return it to a more natural condition by restoring the natural form and function of the river and its floodplain over the next 50 years.

A total of 134 km of the River Teme was designated as an SSSI in 1996, of this 110 km flows in England together with approximately 5 km of the River Clun and this combined river length forms the study area for this project. The Rivers Teme and Clun support important populations of otter, Atlantic salmon, bullhead, grayling, twaite shad, brook lamprey, sea lamprey, and white-clawed crayfish and the lower reaches of the River Clun are of European importance for the populations of freshwater pearl mussel.

The existing condition of the Teme is influenced by physico-chemical, hydrological, biological and physical factors. The majority of the SSSI remains classified as ‘unfavourable recovering’ due primarily to physical system modification including:

• Weirs • Mills• Hydropower• Bridges• Deflectors• Revetment• Embankments • Invasive species and disease

The overall aim of the project was to address physical habitat issues and devise an appropriate whole river restoration plan to be implemented on the ground.

The river restoration plan was based on a detailed scientific understanding of the river and floodplain and set out a means to which the recovery of the SSSI could be achieved in the long term.

What we did?We conducted an integrated geomorphological analysis and ecological interpretation of physical impacts on the river. This involved auditing and surveying the complete length of the 130km river. • The ecological survey recorded habitats adjacent to both banks of the river following the standard Phase 1 Habitat Survey methodology.

River Teme

Client, Stakeholders, Partners: Natural EnglandLocation: River Teme SSSIDate/Phase: 2013Key: River Restoration Plan, Geomorphology, Ecology, Fisheries, Water Framework Directive

• Aquatic macrophyte surveys were conducted along the full length of the river, with detailed spot check surveys undertaken every 500m, where access allowed. At each spot check site we recorded the species present within the river and sections of bank likely to be frequently inundated.• Any other features of note were also recorded such as evidence of siltation, cattle poaching, fording, bankside modification or pollution.

Photographic records were compiled with photographs taken up and downstream and across the channel. During the walkover survey we also recorded any evidence of protected or notable species, in particular Otter and Badger.

Any evidence of non-native invasive plant species was highlighted and Himalayan Balsam was found to be a particularly severe problem from the middle reaches to the confluence with the Severn. This led to a comprehensive map of non-native, invasive species being compiled for the whole river.

The next steps1. The results were used to generate an outline restoration plan for the river on a reach-by-reach basis2. We identified the likely delivery mechanisms for different aspects of restoration and provided approximate costings3. We assisted Natural England and partners in a consultation exercise with stakeholders4. We produced a final restoration plan, incorporating the results of the consultation exercise Summary of Project Outcomes The river restoration plan builds on an understanding of the morphology and ecology of the river and its floodplain and the relationship of this form with the processes controlling sediment and gravel redistribution along the system. The plan also takes into consideration existing constraints and land uses along the river when considering site based actions and implementation.Identification of key pressures along the River Teme:• Bed erosion, incision and floodplain disconnection• Bank instability• Embankments• Lack of trees and woodland• Poor floodplain management• Invasive species• Channel training and bank revetment• Channel realignment

Identification of restoration opportunities:• Floodplain reconnection• Introduction of riparian woodland• Wet woodland creation• Removal and setting back of embankments• Development of vegetated bars• Soft bank protection• Weir removal• Island development• Woody debris

Project Benefits Development of a river restoration plan which lays out a number of restoration options for the River Teme to be implemented over the next 50 years working with local river owners and managers.

ContactKieran Sheehan: [email protected]: or Matthew Hemsworth: [email protected] for more information see: LInk

Historic influences

Catchment management

Catchment controls

Vegetationcommunities

Biotic modification

Flow hydraulics

Morphology Channel & floodplain management

SSSI ECOLOGYFLUVIAL FORM

& DYNAMICS

CATCHMENT CONTROLS

LOCAL CONTROLS

Historic influences

Catchment controls

Catchment management

DESK BASED OVERVIEW

Flow regime

Sediment regime

Local management

HYDROMORPHOLOGICAL & ECOLOGICAL ASSESSMENT

Options testing

Consistent identification

Flood risk

Economic viability

CONSULTATION

CONCEPTUAL WHOLE RIVER

MODEL

DRAFT RIVER RESTORATION

PLAN

FINAL RIVER RESTORATION

PLAN

Team approach to the development of the restoration plan and all the elements considered