River Wye SSSI Restoration Management Report – Draft For
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River Wye SSSI Restoration Management Report – Draft for Comment Issued for comment January 2015 B228B001 Wye SSSI Restoration_Management Report_FinalDraftForConsultation Contents 1 Introduction 5 1.1 The Lower River Wye 5 1.2 Why do we need to restore the River Wye? 8 1.3 European Directives 10 1.4 Project aims and objectives 10 1.4.1 Outputs 11 1.5 Aim and objectives of the Management Report 11 1.6 Developing the restoration vision and detailed plans 12 1.7 Stakeholder involvement 12 1.8 Limitations 13 2 The Lower River Wye SSSIs and SAC 14 2.1 Wye catchment overview 14 2.2 The Lower Wye 16 2.2.1 River Wye restoration vision 18 2.3 SSSI Management 20 2.4 SSSI condition assessment 20 2.5 SAC condition assessment 21 2.6 Water Framework Directive (WFD) 24 2.6.1 Lower Wye WFD water bodies 24 2.7 Wider environment 27 2.7.1 Designated sites 27 2.7.2 Biodiversity Action Plan (BAP) habitat 27 2.7.3 Historic environment 27 2.7.4 Land use and landscape 27 2.7.5 Amenity and recreation 31 2.7.6 Navigation 31 2.7.7 Fisheries 32 3 Pressures and impacts 33 3.1 Methodology 33 3.1.1 Desk study 33 3.1.2 Field survey 33 3.2 Key findings 33 3.2.1 Dominant geomorphological function and processes 41 3.2.2 Historic records 43 3.2.3 Halcrow (2012) study – Vision Report 46 3.2.4 River Habitat Survey – habitat modification data 50 3.2.5 River Restoration Centre (RRC) 2009 report – Comments on the impact of fishing platform revetments 56 3.2.6 Description of pressures in relation to impacts on channel geomorphology and ecology 56 3.3 Vision for the Lower Wye 62 3.4 Summary 64 4 Potential solutions 67 4.1 Selecting restoration solutions 67 B228B001 Wye SSSI Restoration_Management Report_FinalDraftForConsultation 4.2 Meeting WFD objectives 67 4.3 Room for river approach 67 4.4 Restoration categories 70 4.5 Scale and timing of restoration 70 4.6 Descriptions of the restoration measures 74 4.6.1 Channel restoration 75 4.6.2 Riparian zone improvement 76 4.7 Restoration visualisations 77 5 Reach-by-reach restoration options 86 5.1 Organisation of the options 86 5.2 Prioritising the reaches 91 5.2.1 Prioritisation method 1 91 5.2.2 Prioritisation method 2 91 5.2.3 Prioritisation method 3 91 5.2.4 Prioritisation method 4 92 5.2.5 Summary of prioritised reaches 92 5.3 Restoration plans 93 6 Implementing the plan 103 6.1 Working with landowners and land managers 103 6.2 An opportunity 103 6.3 Prioritisation and cost 106 6.4 Shaping the actions 108 6.5 Delivery mechanisms, guidance and sources of funding 109 6.5.1 Water Framework Directive Improvement Fund 109 6.5.2 European Funding 109 6.5.3 Environmental Stewardship Schemes 110 6.5.4 New Environmental Land Management Scheme (NELMS) 110 6.5.5 Glastir 111 6.5.6 Catchment Sensitive Farming 111 6.5.7 Nutrient Management Plan 112 6.5.8 Forestry Commission English Woodland Grant Scheme 112 6.5.9 Wye and Usk Foundation 112 7 References 113 Appendix A Raw data combined 116 B228B001 Wye SSSI Restoration_Management Report_FinalDraftForConsultation Executive Summary Jacobs was commissioned by the Environment Agency to produce separate Technical and Management Reports for the restoration of the Lower Wye and River Lugg. This is a Management Report on the key morphological pressures and restoration measures for the Lower Wye. The Lower River Wye and is a designated Site of Special Scientific Interest (SSSI) and a Special Area of Conservation (SAC). The river is designated due to the presence of grayling, freshwater pearl mussel, white-clawed crayfish, shad, otter, salmon, bullhead, lamprey, various invertebrate assemblages and water-crowfoot communities. The Upper and Middle Wye are also designated, however those reaches lie within Wales and were not investigated for this Management Report. Reports for the Upper and Middle Wye will be produced separately by Natural Resources Wales (NRW). A combination of all reports will provide a catchment wide restoration strategy for all the SACs and SSSIs in the River Wye catchment. The Lower Wye mainly flows through England; however there is a section around Monmouth that is entirely within Wales. Here the right bank of the river is generally regulated by NRW, whilst the left bank is regulated by Natural England and the Environment Agency. Natural England has subdivided the Lower Wye SSSI into seven management units, six of which are assessed to be in ‘unfavourable condition’. This Management Report provides suggestions to help achieve favourable condition in each of the management units. A desk study and a series of site surveys were carried out in January 2014. In addition, analysis of data from a Halcrow (2012) study and several River Habitat Surveys was undertaken. The main findings were that the Lower Wye is a relatively natural river with few modifications to the channel and planform; the main modifications are croys and bed/ bank resectioning. Other pressures on the catchment are sediment loading from agriculture, abstraction and invasive non- native species, all of which are being addressed out with this restoration plan. Restoration of individual management units will contribute to the Lower Wye SSSI achieving ‘favourable condition’. Based on the desk study and site surveys, the Lower Wye has been divided into 67 reaches and assigned a restoration category. The restoration categories have been decided upon as follows: • Significant restoration (5 reaches): Major works required such as removal of extensive bank reinforcement or realign to a more natural planform. • Assisted natural recovery (34 reaches): Minor works required such as removal of minor channel structures (e.g. croys) and small sections of bed and bank reinforcement. • Conserve/ Natural recovery (24 reaches): Allow current natural processes to continue. No intervention is required or minor improvements such as riparian zone management could be implemented. • Riparian zone management (42 reaches): Grazing management, buffer strips, tree planting and/ or tree management could form part of this option. B228B001 Wye SSSI Restoration_Management Report_FinalDraftForConsultation • Urban (4 reaches): Reaches constrained by urban land use could still be improved in-channel. Future engineering works should use sustainable methods where possible. The Environment Agency and Natural England recognise the challenges linked to the river faced by landowners and managers throughout the catchment. The Statutory Bodies recognise that the successful implementation of a restoration plan will require effective and positive engagement with all stakeholders. The restoration actions are suggested as a means to achieve favourable condition of the SSSI and SAC. Both Lower Wye SSSI Restoration Technical Report and Management Report will inform future decision making by statutory bodies and should help the targeting and uptake of agri-environmental schemes, thus encouraging farmers to seek financial advice to adapt their current practices. The views and concerns of a cross section of stakeholders are being sought through consultation based on these reports. Following consultation, the restoration plans and measures proposed in this Management Report and accompanying Technical Report will need updating along with finalisation of the restoration priorities. This task lies outside of the scope of this commission. B228B001 Wye SSSI Restoration_Management Report_FinalDraftForConsultation Glossary Terminology Definition Anadromous A fish species that migrates from the sea into fresh water to spawn Berm (natural) Deposit of fine material along the edges of a river channel, which has a step change in the gradient of the bank, creating a ledge. It is typically a permanent feature which is vegetated with shrubs and trees where land management allows. The feature generally grows following a flood event, when fresh silt/ sand deposits are laid. It differs from a bar which slopes gently into the channel and is more mobile, less vegetated or vegetated with shorter species, which are quick to establish. Berm (artificial) Artificial berms can be created by using hard or soft engineering at the toe of the bank and filling in with soil or other material. Or where a bank has been reprofiled, and the top of the bank cut away to create a step change in the gradient of the bank. This can often be linked to artificial two- stage channels Catchment Area drained by a river and its tributaries Deposition Laying down of part, or all, of the sediment load of a stream on the bed, banks or floodplain. Mostly occurs as high flows recede. The process forms various sediment features such as bars, berms and floodplain deposits Ecological status A Water Framework Directive (WFD) term. Surface waters are classified as being of Good Ecological Status when each of the quality elements that represent indicators of ecological quality of the water body is classified as being good or high. The quality elements fall into three categories: i) biological quality elements, ii) physico-chemical quality elements and iii) hydromorphological quality elements. Additionally for a water body to achieve overall Good Ecological Status, its chemical quality has to pass. Erosion Removal of sediment or bedrock from the bed or banks of the channel by flowing water. Mostly occurs during high flows and flood events. Forms various river features such as scour holes and steep/ undercut outer banks Favourable Description of the condition of the features for which a SSSI condition or SAC has been designated. Favourable condition means that the SSSI land is being adequately conserved and is meeting its 'conservation objectives’; however, there is scope for the enhancement of these sites.1 Floodplain A floodplain is flat or nearly flat land adjacent to a stream or river, stretching from the banks of its channel to the base of the enclosing valley walls and (under natural conditions) experiences flooding periods of high discharge.