Restoring the River Axe Site of Special Scientific Interest and Special Area of Conservation River Restoration Plan
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Restoring the River Axe Site of Special Scientific Interest and Special Area of Conservation River Restoration Plan September 2019 River Axe Restoration Plan CONTENTS Chapter Page Executive Summary 1 Aim of the restoration plan 1 Working with others 2 Delivering the restoration plan 3 1 Restoration of the River Axe 4 1.1 Introduction 4 1.2 The need for restoration 6 1.3 A restoration vision 6 1.4 How can we deliver this restoration? 7 1.5 Our approach 7 1.6 How to use this plan 9 1.7 Who is this plan for? 10 1.8 Development of the plan 10 1.9 How this plan relates to other plans 10 2 The River Axe Site of Special Scientific Interest 13 2.1 Geology and hydrology 13 2.2 Ecology 14 2.3 Conservation objectives for the River Axe SSSI 15 2.4 Condition of the River Axe SSSI 15 2.5 Water Framework Directive objectives 18 2.6 Land use and land use change 19 2.7 Water quality 20 2.8 Flood risk management 20 2.9 Invasive non-native species and disease 21 2.10 Influences on geomorphology and channel change 21 2.11 Devon Wildlife Trust - River Axe Corridor Survey 24 3 River sector descriptions 25 3.1 Summary of sector descriptions 25 3.2 Upper sector 27 3.2.1 Physical characteristics 28 3.2.2 Historical change 28 3.2.3 Geomorphological behaviour 29 3.2.4 Significant issues 30 3.3 Mid sector 31 3.3.1 Physical characteristics 32 3.3.2 Historical change 32 3.3.3 Geomorphological behaviour 34 3.3.4 Significant issues 34 3.4 Lower sector 36 3.4.1 Physical characteristics 38 3.4.2 Historical change 38 3.4.3 Geomorphological behaviour 39 3.4.4 Significant issues 40 4 Channel modifications and restoration measures 41 River Axe Restoration Plan 4.1 Introduction 41 4.2 Geomorphology and channel change 41 4.3 Impact of existing modifications 42 4.4 Potential restoration and management options 44 4.5 Summary of restoration options –management sheets 45 5 Consultation, actions and implementation 47 Figures 1.1 Map of River Axe SSSI/SAC 5 3.1 Geomorphological reaches within the SSSI/SAC as identified 26 in BBR 2004 3.2 Map showing upper sector SSSI units and geomorphological 27 reaches 3.3 Upper sector length of each characteristic bank type 30 3.4 Map showing mid sector SSSI units and geomorphological 31 reaches 3.5 Mid sector length of each characteristic bank type 35 3.6 Map showing lower sector SSSI units and geomorphological 36 reaches 3.7 Lower length of each characteristic bank type 40 5.1 Remedial actions location plan 49 Tables 1.1 Summary of consultation when developing the River Axe Restoration Plan 2.1 Summary of condition of River Axe SSSI management units 16 2.2 Summary of influences on sediment and morphology in the 22 Axe catchment 3.1 Upper sector features summary 30 3.2 Mid sector features summary 35 3.3 Lower sector features summary 40 4.1 Assessment approach 43 4.2 Remedial priority issues 43 4.3 Summary of potential solutions. 45 4.4 Management Sheets 46 5.1 Indicative remedial action programme 48 Glossary 49 Annex 1 Management sheets A1.1 1 Riparian zone management 2 Weycroft Weir 3 Town Weir 4 Stoney Bridge and Axminster Flood Defence Scheme 5 Whitford gauging station, bridge and blockstone weirs 6 Bow Bridge A35 blockstone weirs 7 Weycroft Bridge 8 Bank Revetments Annex 2 Decision making related to structures such as weirs A2.1 and sluices Annex 3 Maps of features and recommendations for riparian A3.1 zone management River Axe Restoration Plan Annex 4 World War II Taunton Stop Line Woodhayne Pillbox A4.1 case example Annex 5 World War II Taunton Stop Line Whitford Pillbox case A5.1 example Annex 6 Wadbrook Farm case example A6.1 Annex 7 Summary of Draft Consultation Responses A7.1 Bibliography B.1 River Axe Restoration Plan Executive Summary The River Axe is designated as a Site of Special Scientific Interest (SSSI) under the Wildlife and Countryside Act 1981 and as a Special Area of Conservation (SAC) under the Conservation of Habitats and Species Regulations 2010. The 2011 Natural England condition assessment (ECUS, 2011) of the River Axe SSSI showed that the site is in unfavourable condition. The reasons for unfavourable condition include physical modifications such as weirs, poor riparian habitat quality due to heavily grazed and impoverished riparian structure, invasive plants, diffuse water pollution and siltation. For the River Axe SSSI, Natural England has identified a range of actions or ‘remedies’ required to get the river into favourable condition. The actions required include developing a river restoration plan and initial implementation of actions. Other actions include implementing a diffuse water pollution plan, catchment sensitive farming initiatives, and an invasive species control strategy. The River Restoration Plan focuses on actions that can be undertaken within the SAC river channel and river corridor. This then complements the Diffuse Water Pollution Plan that addresses wider catchment input pressure. Catchment Sensitive Farming initiatives provides support and a delivery route for works across both of these plans. The UK Government’s ‘Biodiversity 2020’ strategy includes a commitment to ensure that at least 50% of designated SSSIs achieve ‘favourable condition’, (i.e. the site is being adequately conserved and is meeting its 'conservation objectives’) and that 95% of sites are maintained in ‘favourable or recovering’ condition by 2020. In addition, the European Water Framework Directive (WFD) requires all EU Member States to protect and, where possible, enhance the condition of all bodies of water. The Water Framework Directive requires protected areas including the River Axe Special Area of Conservation to be meeting their objectives by 2015 (or in cases where there are significant pressures to address, 2021 or 2027). The river is not currently achieving the required standard of Good Ecological Status (GES). As the River Axe is not currently achieving its SSSI or WFD objectives, the Environment Agency, Natural England and others are obliged to undertake work to ensure that the required standards are achieved in the future. This River Restoration Plan and its implementation (in combination with other actions) seeks to ensure that the River Axe achieves its SSSI and WFD objectives. Aim of the restoration plan The aim of this strategic restoration plan is to identify high level river restoration or enhancement actions to address the physical conditions of the River Axe that are contributing to unfavourable condition. This includes the following specific objectives: 1. Determine the impacts of physical modifications, condition and management on the geomorphology and ecology of the SSSI river. 2. Provide an outline restoration plan for the SSSI river on a reach-by-reach basis, taking into account immovable constraints. 3. Identify potential delivery mechanisms. 1 River Axe Restoration Plan The catchment has a complex history of man-made changes, many of which have significant cultural, heritage and social values associated with them. The realistic aim for the Axe SSSI is to manage and restore as much dynamic function to the river as possible, within current immovable constraints in order to provide the conditions required for river wildlife to flourish. We are not aiming to restore the entire river to an unmodified state. The plan outlines assessments that have been carried out and identifies restoration options intended to naturalise river processes, support catchment sensitive farming initiatives, and encourage riparian management that favours biodiversity. It provides a framework for the improvement in the physical habitat condition of the river over long timescales, and will inform future decision-making. The plan focuses on the SSSI river and its river corridor and alone cannot deliver favourable condition of the SSSI and SAC. Further work is required throughout the Axe catchment which will be delivered through the Diffuse Water Pollution Plan and the invasive species strategy. Working with others Natural England and the Environment Agency are jointly responsible for leading development of the strategic plan. However a range of interested parties and mechanisms will also be involved in developing and implementing particular options - this requires effective and positive engagement with landowners, land managers and stakeholders. Natural England and the Environment Agency will take steps to involve relevant individuals and representative groups in developing actions from this strategic plan. We will work with the East Devon Catchment Partnership and other interested parties to take it forward, with detailed discussions taking place with landowners and managers to develop reach specific actions. Whilst some actions will be completed relatively quickly over the next few years, other measures will take more time to develop, and be implemented over long timescales. The detail of any restoration projects will be developed in conjunction with landowners and other stakeholders, in order to identify constraints and design appropriate restoration options. Permissions from landowners, Natural England and the Environment Agency will be required for restoration projects, all of which will be subject to a Habitats Regulations Assessment. Landowner participation is key to delivery and detailed discussions and agreement with landowners about specific river reaches is recognised as being an essential part of developing detailed restoration projects and undertaking site specific actions in coming years. The importance of agriculture to the rural economy is recognised and a valid consideration when developing river restoration projects. It is acknowledged that that restoration measures affecting land use may only be appropriate for certain locations, will require support (such as from Countryside Stewardship) and may be implemented over long time scales. Actions will only be taken forward once agreement has been gained from the relevant stakeholders, and will be carried out in close partnership to ensure effective delivery and viability of the solution.