River Lugg SSSI Restoration

Technical Report

Draft for Comment and Consultation

January 2015 Revision 2

Document Control Sheet BPP 04 F8 Version 16; October 2013

Project: Wye and Lugg SSSI Restoration Client: Environment Agency Project No: B228B001 Document title: River Lugg SSSI Restoration – Technical Report Ref. No:

Originated by Checked by Reviewed by NAME NAME NAME ORIGINAL Katy Kemble Helena Parsons Helena Parsons NAME As Project Manager I confirm that the INITIALS

Approved by above document(s) have been subjected to Andy Lee Jacobs’ Check and Review procedure and that I approve them for issue DATE 1/09/14 Document status: First draft

REVISION NAME NAME NAME

1 Katy Kemble Alison Flynn Alison Flynn NAME INITIALS

Approved by As Project Manager I confirm that the Helena Parsons above document(s) have been subjected to Jacobs’ Check and Review procedure and that I approve them for issue

DATE Nov 2014 Document status: First revision for client comment

REVISION NAME NAME NAME

2 Katy Kemble Sera Roberts Helena Parsons NAME INITIALS Approved by As Project Manager I confirm that the above document(s) have been subjected to Helena Parsons Jacobs’ Check and Review procedure and that I approve them for issue

DATE Jan 2015 Document status: Draft for consultation

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Executive Summary

Jacobs was commissioned by the Environment Agency to produce separate Technical Reports for the restoration of the River Lugg and the Lower Wye. In addition, Management Reports to complement each Technical Report were also produced by Jacobs. This is a Technical Report on the geomorphological assessment and ecological interpretation of the Lower Lugg.

The River Lugg is a major tributary of the River Wye, crossing both the Welsh and English borders. The River Lugg is designated as a Site of Special Scientific Interest (SSSI) in England. The River Lugg from Hope-under-Dinmore south is also designated as a Special Area of Conservation (SAC) (River Wye/Afon Gwy SAC; EU code UK0012642) under the Habitats Directive. The River Lugg is a cross- boundary catchment straddling the Welsh-English border flowing eastwards from its source at Pool Hill in Powys, Wales through the towns of Presteigne and Leominster, turning south where it reaches its confluence with the River Wye at Mordiford near Hereford. The river shows a good example of transitional river type, with both upland and lowland river morphologies represented.

Natural England has subdivided the River Lugg SSSI into four management units, all of which are assessed to be in ‘unfavourable condition’. There are also two Water Framework Directive water bodies within the English section of the River Lugg, one of which is of poor ecological status and the other good ecological status. This report is required to assess the current geomorphological condition and the main physical pressures on the Lower Lugg to inform a Management Report that will provide suggestions to help achieve favourable condition in each of the management units and the River Wye SAC.

A detailed desk study was conducted for the River Lugg catchment, providing an understanding of the hydrology, historical processes, amenity value, water resources, ecology and the geomorphological background. The desk study identified gaps in the data record, which was used to inform the targeted selection of field survey sites. The initial field surveys were undertaken during January and February 2014, but due to adverse weather conditions and flooding not all sites could be surveyed. As a result further surveys were undertaken during October 2014 to complete the field data collection component of this project. The surveys consisted of a combination of bespoke fluvial audits; stream reconnaissance surveys and spots check surveys of the river reaches. Spot check surveys were typically undertaken to either ground truth data from previous surveys or where access was limited due to intemperate conditions or issues with land access. During the survey, modifications to the natural geomorphology and habitat quality of the river and riparian zone were noted along with any land-use pressures and impacts observed within the river reaches. The data was recorded in the field using mobile mapping technology.

The main findings from the Technical Report have shown that weirs are a major impact on the natural functioning of the Lower Lugg. Major flood defences are also present through Leominster. Outside of these high impact modifications to both the channel and banks, the Lower Lugg is a relatively natural river and although sections have been historically modified, there is evidence of natural recovery in some reaches. Most pressures on habitat suitability along the Lower Lugg include the following:

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 Weirs – presenting a barrier to longitudinal and lateral sediment and flow dynamics as well as fish migration. Weirs also impound water resulting in alteration to flow types and in-channel and marginal habitats.  Historic channel realignment.  Bank reinforcement – preventing geomorphological processes from occurring and removing a sediment source.  Poaching from livestock.  Degradation of the riparian zone – which may lead to accelerated bank erosion, reduced channel shading and increased stream water temperatures, and increased potential for diffuse sediment and pollutants to enter the river.  Invasive non-native species (currently already being addressed outwith this restoration plan).

Restoration of individual management units will contribute to the River Lugg SSSI and River Wye SAC achieving ‘favourable condition’. Based on the desk study and site surveys, the Lower Lugg has been divided into 26 reaches and assigned a restoration category. The restoration categories have been decided upon as follows:

 Significant channel restoration (3 reaches): Major works required such as removal of extensive bank reinforcement or weir removal/modification.  Assisted natural recovery (2 reaches): Minor works required such as removal of minor channel structures and or naturalisation of bank profiles to remove channel resectioning. Implementation of bioengineering techniques to improve modified channels, embankment breaching to improve channel cross-sections, flood storage, wet woodland and backwater creation.  Natural recovery/conserve and protect (3 reaches): Allow current natural processes to continue. No intervention is required or minor improvements such as riparian zone replenishment could be implemented.  Riparian zone management (18 reaches): Grazing management, buffer strips, tree planting and/or tree management to improve sediment budgets or encourage natural temperature control.

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 in the accompanying management report are suggested as a means to achieve favourable condition of the SSSI and SAC. Both the River Lugg 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.

Given that the River Lugg is a tributary of the River Wye and forms part of the wider Wye catchment area, this Technical Report and associated restoration Management Plan will link to the Wye catchment plan being developed by the Wye and Usk Foundation (WUF). The WUF catchment plan will look at all aspects of the catchment and incorporate this Lugg River Restoration Plan (RRP) and other complementary initiatives for the SSSI/SAC such as the Nutrient Management Plan. The catchment plan will hopefully identify the RRP as the place to find the details of what is required for the restoration of the SSSI/SAC.

The views and concerns of a cross section of stakeholders are being sought through public consultation based on these reports. Following consultation, the restoration

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plans and measures proposed in this Technical Report and accompanying Management Report will need updating along with finalisation of the restoration priorities.

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Contents

1 Introduction 12 1.1 Background Information 12 1.2 Rationale for Restoration of River Lugg 13 1.3 Project Aim and Objectives 14 1.4 Outputs 15 1.5 Aims and Objectives of the Technical Report 15

2 River Lugg SSSIs and SAC 16 2.1 River Lugg Designations and Ecological Features 16 2.2 Habitat and Species Requirements 21 2.2.1 Water Crowfoot Communities 23 2.2.2 Lamprey (Lampetra spp.) 24 2.2.3 Shad (Alosa spp.) 24 2.2.4 Atlantic Salmon (Salmo salar) 25 2.2.5 Bullhead (Cottus gobio) 26 2.2.6 European Otter (Lutra lutra) 26 2.2.7 White-clawed Crayfish (Austropotamobius pallipes) 27 2.3 SSSI Condition Status 28 2.4 SAC Condition Status 30 2.5 Water Framework Directive 31

3 Method 34 3.1 Overview of Method 34 3.2 Desk Based Assessment 34 3.3 Field Survey 35 3.3.1 Overview 35 3.3.2 Definition of a Geomorphological Reach 38 3.4 Study Area 38 3.5 Data Analysis and Reporting 46 3.6 Limitations and Assumptions 46 3.7 Developing the Restoration Vision and Detailed Plans 47

4 Catchment Characteristics 48 4.1 Catchment Overview 48 4.2 Geomorphological Background 48 4.2.1 Geology in the Lugg Catchment 48 4.2.2 Soils within the Lugg Catchment 50 4.2.3 Sediment Transport Characteristics 52 4.3 Land Use 54 4.4 Sci-Map Outputs for the Lugg Catchment 55 4.5 Agri-environment Schemes 59 4.6 Channel Change and Modifications 59 4.6.1 Historical Channel Change and Modifications 59 4.6.2 Past River Management Practices 59 4.6.3 Lugg Weir Report 61

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4.7 Hydrology 62 4.8 Flood Risk 63 4.9 Water Resources 69 4.9.1 Water Abstraction 69 4.9.2 Flow Regulation 69 4.9.3 Water Quality 69 4.10 Ecology 70 4.10.1 Fish 70 4.10.2 Invertebrates 71 4.10.3 Birds 71 4.10.4 Alien Invasive Species 71 4.10.5 Phytophthora 72 4.11 RHS Habitat Modification Score Analysis 72 4.12 Wider Environment 75 4.12.1 Designated Sites 75 4.12.2 Biodiversity Action Plan (BAP) Habitat 79 4.12.3 Historic Environment 79 4.12.4 Landscape 84 4.12.5 Amenity, Recreation and Navigation 86

5 Contemporary River Characteristics 87 5.1 Geomorphological Characteristics 87 5.1.1 Channel Planform 87 5.1.2 Floodplain Connectivity 87 5.1.3 Flow Variation 88 5.1.4 Bed Substrate 89 5.1.5 Erosion 89 5.1.6 Deposition 90 5.2 Land Use and Vegetation 91 5.3 Channel Modifications 92 5.3.1 Weirs 92 5.3.2 Embankments 95 5.3.3 Bridges 95 5.3.4 Channel Straightening and Widening 95 5.3.5 Bank Reinforcement 98 5.4 Point and Diffuse Sediment Sources 99 5.5 Geomorphological Function and Processes 104

6 Catchment Pressures and Ecological Condition 108 6.1 Catchment Pressures 108 6.1.1 Modifications 109 6.1.2 Sediment 110 6.1.3 Riparian Zone Degradation 110 6.1.4 Hydrological Connection between River and Floodplain 112 6.2 Effect of Physical Habitat Modifications on Ecological Condition 114

7 Restoration Potential 121 7.1 Summary of Restoration Potential 121 7.2 Potential Restoration Measures 122 7.3 Descriptions of Restoration Measures 123 7.3.1 Riparian Buffer and Woodland Regeneration 124 7.3.2 Weir Removal or Modification 124

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7.3.3 Land Management Measures 124 7.3.4 Channel Cross Section Enhancements 125 7.3.5 Removal/Breaching of Embankments 126 7.3.6 Hydrological Connectivity and Flood Storage 126 7.4 Summary of Restoration Measures 126 7.5 Categorisation of Restoration Measures 129 7.6 Constraints 133

8 Implementing the Plan 134 8.1 Stakeholder Involvement 134 8.2 Restoration Prioritisation 134 8.3 Shaping the Actions 135 8.4 Delivery Mechanisms, Guidance and Sources of Funding 135

9 References 137

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Glossary

Terminology Definition Anadromous A fish species that migrates from the sea into fresh water to spawn. Bank toe The base of the bank. 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.

Artificial berms may be created by using hard or soft engineering at Berm (artificial) the toe of the bank and filling in with soil or other material. They may also be created 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 may 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. Ecological status may be Bad, Poor, Moderate, Good or High. Ecological status comprises quality elements that fall into three categories: i) biological quality elements, ii) physico-chemical quality elements and iii) hydromorphological quality elements. Ecological status is also influenced by Chemical status. 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 outer banks. Favourable Description of the condition of the features for which a SSSI or SAC condition 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. Geomorphology The study of landforms and the processes that create them. Good ecological The status of a heavily modified or an artificial body of water, so potential classified in accordance with the relevant provisions of Annex V of the River Basin Management Plan. Good ecological WFD term denoting a slight deviation from ‘reference conditions’ in a status water body, or the biological, chemical and physico-chemical and hydromorphological conditions associated with little or no human pressure. A primary aim of the WFD is for all water bodies to achieve

1 Taken from Natural England SSSI Glossary http://www.naturalengland.org.uk/ourwork/conservation/designations/sssi/glossary.aspx [Accessed on 24/03/2014]

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Terminology Definition good ecological status. For a water body to achieve overall good ecological status, all quality elements must be ‘good’ or ‘high’ and its chemical quality has to pass. Glide Deeper water flowing smoothly over a river bed. Occasional larger cobbles or boulders on the bed may create some surface disturbance. Planform River channel pattern when viewed from above. This often referred to as either straight, sinuous, meandering or braided. Poaching The erosion of banks caused by livestock trampling. Poaching may be a problem when livestock are wintered on grassland, particularly around gateways, feeding areas and watering points. This may lead to risks of soil erosion and compaction. Poaching may occur where the land is ‘cut-up’ through livestock moving or tramping on wet soils. This removes the vegetative cover, leaving the soil open to the elements and prone to being washed away via surface water run-off and may pollute watercourses. Pool Deeper, steadier water. Pools are usually located at bends in watercourses, and depth increases towards the outside of a bend. Population A term used in waste-water treatment to express the ratio of the sum equivalent of pollution load produced during 24 hours by industrial facilities and services to the individual pollution load in household sewage produce by one person in the same time. Pressure The influence or effect of something, for example land use pressure that causes a change. Pressures include morphological alterations, abstraction, diffuse source pollution, point source pollution and flow regulation. In the context of the WFD a significant pressure is one that, on its own, or in combination with other pressures, would be liable to cause a failure to achieve the environmental objectives set out under Article 4. Reach A length of channel which, for example, may have a homogeneous (similar) geomorphology (river type) or restoration solution. Reference For any surface water body type, reference condition is a state in the conditions present or in the past where there are no, or only very minor, changes to the values of the hydromorphological, physico-chemical, and biological quality elements which would be found in the absence of anthropogenic disturbance. Remedy Natural England has a programme of remedies to address pressures impacting on the condition status of SSSIs. Remedies include river restoration projects; invasive non-native species control programme; Diffuse Water Pollution action and catchment sensitive farming. Remedies may be used in isolation or in combination to address the pressures affecting the condition of a SSSI. Re-profiling The reshaping of a river bank. May be a reflection of channel modification (impact) or restoration. Riffle A stream bed accumulation of coarse alluvium typically linked with the scour of an upstream pool. They are characterised by shallow, fast-flowing water with unbroken standing waves flow type over gravel-pebble or cobble substrate. Channel substrate must be unconsolidated to provide suitable spawning habitat. Riparian zone Strip of land along the top of a river bank. Plant communities along the river banks are often referred to as riparian vegetation. Run Fast flow of water, deeper than riffles and usually with a stony or rocky bed which creates a rippled surface. Siltation/ shoaling Shallowing of channel due to deposition along bed, for example where a riffle is located.

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Terminology Definition Table top A production system which allows fruit to be grown above the ground production (typically over 1m) in grow bags. This makes the harvesting process easier and reduces the risk of soil borne diseases. Threat Factor that could cause failure of river management objectives. A condition “threats” system is used to identify threats and their level of risk to the condition of an unfavourable recovering or favourable SSSI unit; the action(s) to address the threat; the organisation(s) responsible for the action; when the action is to be implemented. Tributary A stream or river which flows into a larger river. A tributary does not flow directly into the sea. Unfavourable Description of the condition of the features for which a SSSI or SAC condition has been designated indicating that the special interest of the SSSI unit is not being conserved and it will not reach favourable condition unless there are changes to the site management or external pressures. The longer the SSSI unit remains in this poor condition, the more difficult it will be, in general, to achieve recovery.2 Unfavourable Unfavourable recovering condition is often known simply as recovering 'recovering'. SSSI units are not yet fully conserved but all the condition necessary management measures are in place. Provided that the recovery work is sustained, the SSSI will reach favourable condition in time. In many cases, restoration takes time. Woodland that has been neglected for 50 years will take several years to bring back into a working coppice cycle. A drained peat bog might need 15-20 years to restore a reasonable coverage of sphagnum.3 Water body A water body is a WFD term and is the division of rivers, lakes, tidal/ coastal and groundwaters into discrete units for management and reporting. Water bodies are defined using criteria set out in the WFD legislation. Woody debris Woody debris includes logs, sticks, branches, and other wood that falls into streams and rivers. This debris may influence flow and the shape of the stream channel.

Acronyms AEP Annual Exceedance Probability BAP Biodiversity Action Plan CAP Common Agricultural Policy CCW Countryside Council for Wales - As of 1st April 2013 Natural Resources Wales took over the functions of the CCW, Environment Agency Wales (EAW) and Forestry Commission Wales). CEH Centre for Ecology and Hydrology CFMP Catchment Flood Management Plan CMP CCW’s Core Management Plan COGAP Code of Good agricultural Practice CRF Catchment Restoration Fund CSF Catchment Sensitive Farming DEFRA The Department for Environment, Food and Rural Affairs DWPAP Diffuse Water Pollution Action Plan EA Environment Agency

2 Taken from Natural England SSSI Glossary http://www.naturalengland.org.uk/ourwork/conservation/designations/sssi/glossary.aspx [Accessed on 24/03/2014] 3 As above

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ESS Environmental Stewardship Scheme EWGS English Woodland Grant Scheme FAS Flood Alleviation Scheme FRCM Flood Risk and Coastal Management GIS Geographical Information System HLS Higher Level Stewardship HMWB Heavily Modified Water Body NE Natural England NRW Natural Resources Wales (which includes former organisations Environment Agency Wales, Forestry Commission Wales and Countryside Council for Wales). OS Ordnance Survey RBMP River Basin Management Plan RSA Restoring Sustainable Abstraction SAC Special Area of Conservation SPA Special Protection Area SSSI Site of Special Scientific Interest WFD Water Framework Directive WUF Wye and Usk Foundation

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1 Introduction

1.1 Background Information

The River Lugg is the major tributary of the River Wye, crossing both the Welsh and English borders. The River Lugg is designated as a Site of Special Scientific Interest (SSSI) in England, with the river sub-divided into four units. Information on the SSSI and subsequent units is provided in more detail in Section 2 including a location plan. The River Lugg from Hope-under-Dinmore south is also designated as a Special Area of Conservation (SAC) (River Wye/Afon Gwy SAC; EU code UK0012642) under the Habitats Directive. Jacobs was commissioned by the Environment Agency to produce separate Technical Reports for the restoration of the River Lugg and the Lower Wye. In addition, Management Reports to complement each Technical Report were also produced by Jacobs. This is a Technical Report on the geomorphological assessment and ecological interpretation of the Lower Lugg.

The Lugg rises at its upland source on Pool Hill in Powys and flows in a south- easterly direction to its confluence with the River Wye near Mordiford. The River Lugg is approximately 101km long and has a catchment of approximately 1,077km2. The River Lugg has a number of tributaries, the main one being the River Arrow that meets the Lugg in Leominster. The River Lugg is considered to be one of the best British mainland examples of both a clay river and a river displaying a transition from nutrient-poor to naturally nutrient-rich water chemistry (River Lugg Conservation Strategy, 1996).

The Upper section of the Lugg is within the Welsh borders. For this reason, restoration planning has not been undertaken in detail for this section of the river; however, consideration for the catchment context has been reflected within this report. A restoration plan for the Upper Lugg and tributary SSSIs is being commissioned separately by Natural Resources Wales. It is important to note that human activities in the Upper Lugg may be impacting on habitats in the Lower Lugg. It is anticipated that the combination of all reports will provide a catchment wide restoration strategy for the SAC and SSSIs of unfavourable condition along the Lower Lugg.

The Lower Lugg is regulated by Natural England and the Environment Agency. These organisations provide advice on the management of the river and regulate the management practices.

A major pressure on the River Lugg catchment is sediment loading from agriculture, which is likely to be a primary reason for the management units failing to achieve favourable condition. Other pressures include abstraction and invasive non-native species (INNS). To address these pressures, Natural England has a programme of SSSI remedies which includes ‘River Restoration Projects’. River restoration in combination with other remedies such as an INNS control programme, diffuse water pollution action, Nutrient Management Plan and catchment sensitive farming all need to be progressed to improve the condition of the River Lugg.

Common Standards Monitoring Guidance for Rivers (JNCC, 2014) identifies attributes which are selected according to those that provide the best measures of ecological integrity and quality for rivers. The attributes relate to the pressures

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affecting rivers. The assessment of these attributes assists in the determination of whether a river is in favourable condition.

Attributes used to assess the condition of SSSIs and SACs designated for river habitats and species have been agreed by UK conservation agencies and are set out in the Common Standards Monitoring Guidance for Rivers (JNCC, 2014). Having identified the river types present in a SSSI, the aim is to provide favourable habitat conditions appropriate to that river type for the characteristic biological community, rather than focusing on restoration to benefit a particular species.

1.2 Rationale for Restoration of River Lugg

The English River Lugg SSSI has been divided into four management units by Natural England. A desk study condition assessment was carried out for each of these English SSSI units in 2010 by Natural England (Natural England, 2014). All of the SSSI units are currently in unfavourable recovering condition. According to the Natural England unit condition assessment, there are a number of pressures within the catchment leading to this condition, including the following:

 Siltation;  Water pollution from agricultural runoff and discharge;  Invasive freshwater species; and,  Agricultural fertiliser use and overgrazing (Unit 3 only).

Actions are in place to begin to address these pressures (e.g. Diffuse Water Pollution Plan and Nutrient Management Plan). However, Natural England has also identified physical habitat modification as a threat to further deterioration of the River Lugg SSSI. As a result, a river restoration strategy and subsequent implementation is required to start addressing these additional pressures within the catchment.

According to JNCC Common Standards Monitoring guidance, 65% or more of River Habitat Survey (RHS) sites must be assigned a HMC (Habitat Modification Class) of 1 to achieve favourable condition. Subsequent examination of RHS data shows that over 40% of the RHS sites along the Lower Lugg were achieving a HMC of 3-5, which is a threat to the condition of the Lower Lugg SSSI (see Section 4.8).

Restoration of the management units and features currently in unfavourable condition will contribute directly to moving the river towards favourable condition. In England, the restoration of the management units may also benefit the Environment Agency Flood Risk and Coastal Management (FRCM) Outcome measure 4c (length of river improved) (although the Environment Agency plays no role in the determination and management of the SSSI units).

‘Conservation objectives’ describe the targets for the River Wye SAC to reach and maintain favourable condition for the habitats and species for which it is designated. The favourable condition targets may be more stringent than those required to meet the Water Framework Directive (WFD) objectives of good ecological status or good ecological potential (GES/GEP). Under article 4(2) of the WFD, where more than one objective relates to a given body of water, the higher target applies. Restoration of the River Lugg SSSI (England) and River Wye SAC will also contribute to the achievement and/or maintenance of GES on water bodies within the protected areas under the WFD.

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Although the current study is concerned with directly restoring the physical modifications to the rivers in the SSSIs and SAC, some measures may indirectly improve water quality (such as improving riparian buffer strips, potentially reducing diffuse pollution from agriculture). More information on the pressures facing the water environment may be found in the Severn River Basin Management Plan (RBMP), which is produced under the WFD. Annex D of this RBMP also outlines actions for Protected Areas such as the Wye SAC. Flow regulation and abstraction regime have not been investigated specifically within this project but it is expected that the findings of this project will be complementary to other programmes of work currently being carried out by the Environment Agency and Natural Resources Wales.

All the various pressures and subsequent related pressures that have been identified within the River Lugg catchment need to be addressed to enable to condition of the SSSI and SAC units to achieve favourable condition.

1.3 Project Aim and Objectives

The project aims to identify at a strategic level river restoration or enhancement options that assist in achieving favourable condition or unfavourable recovering condition for the physical habitats of the River Lugg SSSIs and SAC (River Wye/Afon Gwy SAC) units. The restoration actions will also help the sections of the river currently failing under the WFD to achieve ‘good ecological status’. Work to develop the River Lugg restoration strategy has the following specific objectives:

1. Undertake a geomorphological analysis and ecological interpretation of physical impacts on the River Lugg designated sites, comprising a desk study, gap analysis and targeted field survey. 2. Provide a broad assessment of the condition of the SSSI based on physical habitat criteria alone against the physical habitat condition targets set for the study area using existing data on physical habitat modification and relevant sections of the JNCC Common Standards Monitoring Guidance (2014). 3. Produce restoration visions for the sections of the River Lugg in England, identifying river geomorphology and habitat links, including those critical to the achievement of favourable condition. 4. Provide an outline restoration plan for the river on a reach-by-reach basis, which is linked specifically to the conservation objectives for species and habitats of the SAC and SSSIs. 5. Establish the wider environmental baseline and receptors that may be impacted by restoration options. 6. Identify potential delivery mechanisms and provide approximate costs for the different aspects of restoration.

The plan is intended to provide a framework for the restoration and enhancement of the River Lugg SSSIs and SAC (River Wye/Afon Gwy SAC) unit over long timescales, potentially the next 20 to 40 years. Physical habitat restoration alone will not restore the river to favourable condition (or good ecological status where this is failing); however, actions taken will contribute to achieving these targets. Continued action is needed in parallel with the remedies delivered by other initiatives including the Diffuse Water Pollution Plan, Nutrient Management Plan and invasive non-native species control. Restoration of physical habitat also needs to look beyond the channel and riparian zone and consider the wider floodplain, valley and land use management, pressures and impacts.

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1.4 Outputs

1. A technical report detailing the geomorphological and ecological appraisal, SSSI condition assessment (physical habitat only) and wider environment considerations. 2. Mapped outputs showing key geomorphological features and management changes (included in the technical report). 3. A GIS database of raw geomorphological data and associated data (e.g. photos). 4. A management report containing the outline restoration plan. The report will detail existing management regimes, restoration options, potential delivery mechanisms and indicative costs. 5. A package of consultation material for a stakeholder consultation event.

1.5 Aims and Objectives of the Technical Report

This Technical Report is intended for use by river managers and regulating bodies (specifically Natural England, the Environment Agency and Natural Resources Wales) as supporting information for the accompanying River Lugg Restoration Management Report. The aim of the Technical Report is to present the findings of the geomorphological assessment and ecological interpretation of physical impacts on the river (i.e. channel and floodplain modifications) and to determine the types of restoration measures that could be put in place to rectify this. The data collected during the field survey may be viewed on an interactive mapper tool on the CD accompanying this report.

The accompanying Management Report incorporates summaries of the geomorphological and ecological findings of the Technical Report and presents the potential restoration actions that are suggested to achieve favourable condition in the River Lugg SSSIs and SAC (River Wye/Afon Gwy SAC) unit. The Management Report will therefore inform future decision making by the Environment Agency, Natural Resources Wales and Natural England (Statutory Bodies). Implementation of the Management Report will require effective and positive engagement with stakeholders.

The River Lugg restoration plan will feed into a wider catchment based approach and a catchment plan. The River Lugg forms part of the wider Wye catchment area and the Wye catchment plan is being developed by the Wye and Usk Foundation (WUF). The WUF catchment plan will look at all aspects of the catchment and incorporate the River Restoration Plan (RRP) and other complimentary initiatives for the SSSI/SAC, such as the Nutrient Management Plan.

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2 River Lugg SSSIs and SAC

2.1 River Lugg Designations and Ecological Features

The River Lugg is designated as a SSSI and the lower section forms part of the River Wye SAC (Figure 2.1). The Lugg is also bordered by two SSSIs near to its confluence: the River Wye (in unfavourable condition) and the Lugg and Hampton Meadows Unit 1 and Unit 2 (in favourable condition). The River Wye SAC is designated with the primary reason for being a ‘watercourse of plain to montane levels with Ranunculus fluitantis and Callitricho-Batrachion vegetation’ under Annex I of the EC Habitats Directive.

The River Lugg is considered to be one of the best British mainland examples of both a clay river and a river displaying a transition from nutrient-poor to naturally nutrient-rich water chemistry (River Lugg Conservation Strategy, 1996). The SSSIs are designated for the following river habitat types (Mainstone, 2007) (more detail is provided in Table 2.1):

 Type VIII: Highland river with gravel and peat;  Type VI: Rivers on sandstone, mudstone and hard limestone;  Type II: Clay rivers with additional coarse substrates; and,  Type I: Fast flowing calcareous small rivers on mixed substrates.

These habitats support characteristic species including Atlantic salmon, bullhead, otter and lamprey. The Lugg is also designated for riparian woodland and fluvial geomorphology.

Table 2.1 River habitat types along the River Lugg based on Holmes (1983) plant community groups. These habitat types are typical of the differing types would look under conditions of minimal human influence. Type Group Description Location Type VIII C4iii Oligo-mesotrophic rivers, Source to Gravel predominantly highland rivers (Wales) with gravel and peat Type VI B4i Rivers on sandstone, mudstone Gravel to Aymestrey and hard limestone – small (Wales and England) sandstone river with shaded margins B3i Large rivers in their lower Wharton to Hope-under- reaches on Old Red Sandstone Dinmore (England) Type II A2iii Clay rivers with additional coarse Leominster to Mordiford substrates (England) Type I A1vi Lowland, low gradient rivers Wergins Bridge (Sutton St. Nicholas – England)

The section of the River Lugg downstream of Hope-under-Dinmore is a unit of the River Wye SAC designated for river habitat that supports certain internationally notable aquatic plant communities and populations of river and brook lamprey, Atlantic salmon and otter. Some features that contribute to SSSI status also contribute to SAC status and are outlined in Table 2.2.

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Table 2.2 Special features that are a primary reason for the selection of sites for SSSI or SAC designation on the River Lugg Special feature SSSI SAC Type VIII Highland river with gravel and peat  Type VI Rivers on sandstone, mudstone and hard limestone  Type I Fast flowing calcareous small rivers on mixed substrates  Type II Clay rivers with diverse substrates and flow patterns  Water crowfoot (Ranunculus)  Pillwort Pilularia globulifera  Water Vole Arvicola terrestris  Pea mussel Pisidium tenuilineatum  Aquatic beetles/alder fly Riolus cupreus & R. subviolaceus/Sialis  Allis shad Alosa alosa  White-clawed (or Atlantic stream) crayfish Austropotamobius   pallipes Twaite shad Alosa fallax   Atlantic salmon Salmo salar   Sea lamprey Petromyzon marinus  Brook lamprey Lampetra planeri   River lamprey Lampetra fluviatilis   Bullhead Cottus gobio   European Otter Lutra lutra   Watercourses of plain to montane levels with the Ranunculion  fluitantis and Callitricho-Batrachion vegetation Geological/Geomorphological SSSI feature River Lugg Meanders 

As a result of the River Lugg being a transboundary river that flows through both Wales and England, the river has been divided into two separate SSSIs; the Welsh River Lugg (Wales) SSSI and the River Lugg (England) SSSI. The River Lugg SSSI (England) has been divided further into four units by Natural England (all of which are in unfavourable condition):

 Unit 1 – River Wye confluence to Hampton Court Bridge;  Unit 2 – Hampton Court Bridge to Leominster;  Unit 3 – Leominster to Mortimer’s Cross; and,  Unit 4 – Mortimer’s Cross to Presteigne.

Within Unit 1 of the English SSSIs there is another area designated as a SSSI which is referred to as the Lugg Meanders. The Lugg Meanders are 11.16ha in size and currently in favourable condition with features visible and intact. The natural fluvial processes are deemed unconstrained, with natural erosion occurring which may require field fences to be moved as a result (Natural England, 20134).

The UK conservation agencies set conservation objectives for SSSIs/SACs, using agreed national standards, and regularly assess their condition. These objectives are based on a range of chemical, hydrological and physical targets (some quantitative, some descriptive) which enable the habitat to support the characteristic flora and fauna of that habitat type.

4 Natural England (2013). Condition of SSSI units [online]. Available at: [Accessed on 18/01/13]

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Favourable condition (in broad terms) is based on assessment of a habitat or species condition, from a nature conservation perspective. Habitats or species are judged to be in favourable condition when they are being adequately conserved and are meeting their 'conservation objectives'.

For the River Wye SAC, the following features must be maintained of restored in order to achieve Favourable Conservation Status of its Qualifying Features (see Table 2.5):

 The extent and distribution of qualifying natural habitats and habitats of qualifying species;  The structure and function (including typical species) of qualifying natural habitats;  The structure and function of the habitats of qualifying species;  The supporting processes on which qualifying natural habitats and habitats of qualifying species rely;  The populations of qualifying species; and,  The distribution of qualifying species within the site.

The CCW5 Core Management Plan (Dyson, 2008) sets out conservation objectives for the River Wye SAC (Box 1). This is for the whole SAC, including the Upper, Middle and Lower Wye as well as tributaries within the SAC.

5 CCW is now part of Natural Resources Wales.

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Box 1: CCW* Core Management Plan conservation objective for the watercourse

1. The capacity of the habitats in the SAC to support each feature at near-natural population levels, as determined by predominantly unmodified ecological and hydromorphological processes and characteristics, should be maintained as far as possible, or restored where necessary. 2. The ecological status of the water environment should be sufficient to maintain a stable or increasing population of each SAC feature, including elements of water quantity and quality, physical habitat and community composition and structure. 3. Flow regime, water quality and physical habitat should be maintained in, or restored as far as possible to, a near-natural state, in order to support the coherence of ecosystem structure and function across the whole area of the SAC. 4. All known breeding, spawning and nursery sites of species features should be maintained as suitable habitat as far as possible, except where natural processes cause them to change. 5. Flows, water quality, substrate quality and quantity at fish spawning sites and nursery areas will not be depleted by abstraction, discharges, engineering or gravel extraction activities or other impacts to the extent that these sites are damaged or destroyed. 6. The river planform and profile should be predominantly unmodified. Physical modification having an adverse effect on the integrity of the SAC, including, but not limited to, revetments on active alluvial river banks using stone, concrete or waste materials, unsustainable extraction of gravel, addition or release of excessive quantities of fine sediment, will be avoided. 7. River habitat SSSI features should be in favourable condition. Where the SAC habitat is not underpinned by a river habitat SSSI feature, the target is to maintain the characteristic physical features of the river channel, banks and riparian zone. 8. Artificial factors impacting on the capability of each species feature to occupy the full extent of its natural range should be modified where necessary to allow passage, e.g. weirs, bridge sills, acoustic barriers. 9. Natural factors such as waterfalls, which may limit, wholly or partially, the natural range of a species feature or dispersal between naturally isolated populations, should not be modified. 10. Flows during the normal migration periods of each migratory fish species feature will not be depleted by abstraction to the extent that passage upstream to spawning sites is hindered. 11. Flow objectives for assessment points in the Wye Catchment Abstraction Management Strategy will be agreed between EA and CCW as necessary. It is anticipated that these limits will concur with the standards used by the Review of Consents process given in Annex 1 of this document. 12. Levels of nutrients, in particular phosphate, will be agreed between EA and CCW for each Water Framework Directive water body in the Wye SAC, and measures taken to maintain nutrients below these levels. It is anticipated that these limits will concur with the standards used by the Review of Consents process. 13. Levels of water quality parameters that are known to affect the distribution and abundance of SAC features will be agreed between EA and CCW for each Water Framework Directive water body in the Wye SAC, and measures taken to maintain pollution below these levels. It is anticipated that these limits will concur with the standards used by the Review of Consents process. 14. Potential sources of pollution not addressed in the Review of Consents, such as contaminated land, will be considered in assessing plans and projects. 15. Levels of suspended solids will be agreed between EA and CCW for each Water Framework Directive water body in the Wye SAC. Measures including, but not limited to, the control of suspended sediment generated by agriculture, forestry and engineering works, will be taken to maintain suspended solids below these levels.

*CCW is now part of Natural Resources Wales.

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Figure 2.1 SAC and SSSI Location Plan along the River Lugg

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2.2 Habitat and Species Requirements

There are four main river habitat types on the River Lugg, which are major reasons for the SSSI designation. These are shown in Table 2.3 alongside their characteristics under conditions of low anthropogenic impacts. These river types typically support many of the species that are also designated as SAC and SSSI features in the Lugg catchment. These four SSSI river types underpin the general SAC features in the River Lugg catchment.

Table 2.3 JNCC river types reported on surveyed stretches on the Lugg (other types may be present on un-surveyed reaches); major reasons for the SSSI designations of the River Lugg (taken from information in Mainstone, 2007) JNCC river SSSI unit Characteristics of Ecological type (Holmes where JNCC river types under importance et al., 1999) river type conditions of low is present anthropogenic impacts Type I: Unit 4 Low gradient catchments Occasional log jams Lowland, low and river channels would be expected to gradient rivers running over clay or generate stretches of alluvium. Stream power ponded water providing is somewhat variable but additional and is generally low. Bed important habitat materials are likely to be variability as well as dominated by silts and woody debris for sands, with coarser decomposer species. gravels accumulating at River bed gravels or riffles to an extent other coarse substrate dependent on upstream provide an essential but sources and stream generally scant habitat power. Flow patterns for a wide variety of are likely to be invertebrate and fish dominated by glide, with species in these river coarser substrates types. Gravels and underlying occasional swifter flows also riffles and finer materials providing rooting underlying deeper pools. opportunities for species, with an attendant fauna. Type II: Clay Unit 3 and Low gradient catchment Woody debris rivers with 4 with river channels accumulations would diverse running over clay or be expected to substrates alluvium (sometimes contribute to flow type and flow chalk). Stream power variability in this river patterns variable but generally type and create refuge low. Bed materials likely habitats and pools for to be dominated by silts aquatic species. and sands with coarser Woody debris is also gravels accumulating at important for riffles. Flow patterns are decomposer species. likely to be dominated by River bed gravels or glides with coarser other coarse substrate substrates underlying provide an essential but occasional riffles and generally scant habitat finer materials underlying for a wide variety of

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JNCC river SSSI unit Characteristics of Ecological type (Holmes where JNCC river types under importance et al., 1999) river type conditions of low is present anthropogenic impacts deeper pools. invertebrate and fish species in these river types. Type VI: Unit 1 and Catchments tend to be Riparian trees are Base-rich, 3 mid-altitude. Moderate important for providing mesotrophic stream gradients have a source of woody rivers in Welsh substrates dominated by debris, leaf litter and western and SSSI gravels and pebbles. exposed tree root northern Outcropping bedrock and systems as submerged Britain, with a boulders are common habitat and refuge moderate to features creating variable areas for fish and fast current. flow types including step- invertebrates. pools, riffles and glides. Exposed side and mid- channel bars both vegetated and unvegetated are common as well as sandy margins with some vegetation. Where there is a floodplain, active meandering may occur with vertical cliffs and point bars. Type VIII: Welsh Similar to Type VII Vegetation is Moderate- SSSI although steeper and dominated by gradient more energetic, bryophytes (such as sand/shale dominated by cobbles, Rhynchostegium rivers below boulders and bedrock. riparioides, uplands Chiloscyphus polyanthus and Hygrohypnum ochraceum) with exposed bedrock and chutes ideal for a range of riffle-dwelling invertebrates.

Most of the habitats and species found within the River Lugg SSSIs and SAC (River Wye SAC) have specific requirements. This may include a narrow range of tolerances to physical habitat or flow (substrate type, flow type or variation), spatial linkages between life stages, water quality, riparian zone influences or inputs and hydromorphological requirements. The majority of species may utilise suboptimal conditions within an environment. However, to meet the requirements of favourable condition a population must be self-sufficient and sustainable. When considering the condition of a population it is essential to appreciate that the distribution of a given species within a catchment is appropriate to the natural geomorphology, and that channel form may naturally preclude certain species from sections, reaches or whole tributaries if underlying conditions are not naturally suitable for that species.

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Whilst particular species (including SAC species) may form part of the designation for a site, their requirements would normally only be catered for to an extent by the characteristics of habitat type. Exceptions to this include: 1) where there is good reason to believe that a higher level of quality is required by a particular designated species and the river is naturally capable of supplying this quality; 2) where a species is the only designation feature and there is good reason to move away from characteristic habitat form and function of the river.

The following are the characteristics and requirements of a number of species that inhabit the River Wye SAC which covers the River Lugg Unit 1 SSSI up to Hampton Court Bridge.

2.2.1 Water Crowfoot Communities

The Annex II habitat ‘watercourses of plain to montane levels with the Ranunculion fluitantis and Callitricho-Batrachion vegetation’ is a primary reason for the selection of the SAC. Currently, this is classed as being in unfavourable: unclassified condition which is likely to be a result of water quality issues from diffuse pollution (particularly fine sediment) from agriculture (Dyson, 2008). Another adverse factor potentially impacting the condition of this feature is the prevalence of alien invasive species including Japanese knotweed and Himalayan balsam throughout the Lugg catchment (as mentioned in the Severn RBMP and observed during fieldwork).

This habitat type is characterised by the abundance of water-crowfoot Ranunculus spp., subgenus Batrachium (Ranunculus fluitans, R. penicillatus spp. penicillatus, R. penicillatus spp. pseudofluitans, and R. peltatus and its hybrids). Floating mats of these white-flowered species are characteristic of river channels in early to mid- summer. They may modify water flow, promote fine sediment deposition and provide shelter and food for fish and invertebrate fauna.

There are several variants of this habitat in the UK, depending on geology and river type. In each, Ranunculus species are associated with a different assemblage of other aquatic plants, such as water-cress Rorippa nasturtium-aquaticum, water- starworts Callitriche spp., water-parsnips Sium latifolium and Berula erecta, water- milfoils Myriophyllum spp. and water forget-me-not Myosotis scorpioides. In some rivers, the cover of these species may exceed that of Ranunculus species. Three main sub-types are defined by substrate and the dominant species within the Ranunculus community.

The key factors affecting aquatic macrophytes (geology; water chemistry and land use; climate and flow regime; geomorphology; and anthropogenic factors such as disturbance, shading and management) are highly interlinked, acting in combination and over varying time scales. It is therefore often difficult to obtain a clear understanding of the relative importance of each. The effects of geology and flow are of primary importance, and this generally determines which plants may occupy specific locations in the channel. Flow velocity is thought to be the single most important control on the condition of Ranunculus (Hatton-Ellis and Grieve, 2003).

Threats to this habitat include eutrophication, siltation from agriculture, reduced water levels from over abstraction and unsympathetic channel management.

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2.2.2 Lamprey (Lampetra spp.)

Three lamprey species are known to inhabit the River Wye catchment and all are listed as primary qualifying features of the River Wye SAC. These are the sea lamprey (Petromyzon marinus), brook lamprey (Lampertra planeri) and river lamprey (Lampetra fluviatilis). The status along the Lugg for brook lamprey is considered optimal/favourable, whilst the statuses for river and sea lamprey is classed as being unknown (River Lugg Conservation Strategy, 1996).

Ecologically, sea and river lamprey differ from brook lamprey by undertaking migrations between freshwater spawning and juvenile habitats and marine environments. According to the JNCC (2013), there are exceptionally good quality habitats in the Wye which support a healthy population of all three types of lamprey.

The three lamprey species require a juxtaposition of suitable habitats for different life stages (Maitland, 2003), which vary slightly between species. Optimum sea lamprey spawning habitats are similar to salmon (described in Section 2.2.4). Substrate at these spawning sites is usually gravel (9.5-50.8mm diameter) with flows around 1-2m/s and typically 2-40cm deep, although sea lamprey will utilise deeper water. Spawning is temperature driven and differs between the three species (15°C for sea lamprey, 8.5-12.0°C for river lamprey and 10-11°C for brook lamprey). The spawning habitat typically used by river and brook lamprey is also used by trout, particularly due to the slightly smaller substrate sizes.

Once the lamprey eggs hatch into ammocoetes in the spawning site, they drift downstream and burrow into patches of fine sediment, favouring silt or sand beds held in marginal area, backwaters or slow flowing channels. These fine sediments are often associated with high organic content and allow the ammocoetes to burrow.

They remain within the silt/sand beds for a number of years and at this point are filter feeders. The metamorphosis into adult lamprey then only takes a few weeks. Velocity preferences for lamprey ammocoetes ranges from <0.1m/s (river lamprey) to 0.5m/s (brook lamprey). Macrophyte presence also provides cover for the young lampreys. The interconnectivity between habitats for different lamprey life stages is important in maintaining population dynamics, with separation of life stages often reducing the viability of a population.

All lamprey species are adversely affected by a range of anthropogenic activities. Although direct exploitation has decreased in recent years, channel modification may damage suitable habitat and remove spawning/nursery habitat through sediment mobilisation and alteration to flow regimes. Lampreys are indicative of good water quality. Pollution and eutrophication may influence lamprey migration or lead to a reduction in reproductive success (for example through the smothering of gravels with fine sediment). The presence of weirs and in-channel structures within the river may act as barriers to prevent migration. This is particularly important to the sea lamprey, which do not readily ascend over structures like the river lamprey and as such is often restricted to lower river habitats. In addition, entrainment in water abstractions directly impacts lamprey populations.

2.2.3 Shad (Alosa spp.)

There are two species of shad recorded in the River Wye SAC, the twaite shad (Alosa fallox) which is common throughout the Wye and the allis shad (Alosa alosa), which is thought to be rare as there have been no recent records of this species.

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The status of the presence of the allis shad is unknown on the River Lugg due to its rarity; however, it should be noted this could be because no recent records have been collected or numbers were miss-recorded in the past. Twaite shad is confirmed to be present in the lower reaches of the Lugg up to Urdimarsh and it is presumed to be spawning; monitoring hasn’t indicated any decline on the Lugg (River Lugg Conservation Strategy, 1996).

Currently both species are classed as being in unfavourable condition by NRW as a precaution. Data is limited for shad on the River Lugg but it is known that they are vulnerable to decline where there are barriers that prevent migration, as well as pollution and overfishing which also act as key pressures on the species. It is against the law to fish shad in Britain; if caught in nets, these should be returned immediately and without harm.

Shad require water depths of 50-70cm whilst spawning along with a clean, stable, gravel/pebble substrate without an armoured layer and with little fine sediment at the surface substrate. Holding areas of around 2m depth are also required and ideally these should have cover from vegetation and other features such as undercut banks to protect the shad from predators. Interconnectivity of habitats is important (as with other migratory species) between juvenile and adult life stages.

2.2.4 Atlantic Salmon (Salmo salar)

The Wye is considered one of the most productive salmon rivers in Wales with high quality spawning and juvenile habitats in the main channel and its tributary, the River Lugg (River Lugg Conservation Strategy, 1996). Spawning occurs in the lower sections of the Lugg, but weirs and in-channel structures restrict migration to the upper reaches, although it is believed this has improved over recent years.

Atlantic salmon are an anadromous species, spawning in freshwater where they remain as juveniles (1–4 years), before migrating to the open sea. They remain in the marine environment until maturity (1–3 years) at which point they return to freshwater, migrating upstream to breed in the headwaters. Salmon have specific habitat requirements (flow, substrates, temperature) for spawning and each subsequent life stage. For a population to remain sustainable there is a requirement that a high degree of interconnectivity of physical habitats occurs to ensure successful recruitment from spawning.

Spawning occurs in headwater streams in relatively high energy (between 25- 90cm/s), shallow areas (17-76cm) where depressions are created by the adult fish. The gradient is typically less than 3% and the substrate a mix of 2mm-256mm diameter gravel and pebbles. The presence of fine silts is normally low and interstitial spaces need to be kept clear by upwelling flow (Hendry and Cragg-Hine, 2003). The siltation of spawning gravels through inappropriate land management could lead to a reduction in the reproductive success of salmon.

Fry and parr occupy shallow fast flowing water (50-65cm/s) less than 20cm deep, with moderate coarse substrates. Channel cover is very important at all life stages, and for juveniles this may include loose substrate, large rocks, undercut banks, overhanging vegetation and aquatic vegetation.

Adults lie up in deeper holding pools immediately downstream of suitable spawning habitats, where they rest after ascending the watercourse prior to spawning.

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Through the length of the catchment adults use riparian cover, large boulders and areas of deep water during migrations.

The status of Atlantic salmon in the River Lugg is classed as being suboptimal declining/unfavourable declining (River Lugg Conservation Strategy, 1996). The most recent CCW Core Management Plan (CMP) (Dyson, 2008) identifies salmon as failing to meet favourable condition on the River Wye, as a result of poor adult run (i.e. lower number of adult fish returning to the river to spawn than is necessary to meet the conservation target) and a precautionary assessment of juvenile distribution and abundance. The requirement for a higher adult run will ensure long term sustainability of this species. There is currently a ‘catch and release’ policy on the River Wye aiming to increase the adult run within the catchment.

2.2.5 Bullhead (Cottus gobio)

Bullhead is present in the unpolluted mesotrophic streams of the Welsh/English borders. They are found in all but the most oligotrophic headwaters of the River Lugg (River Lugg Conservation Strategy, 1996). The status of bullhead along the Lugg is considered to be optimal/favourable. However, bullhead is sensitive to pollution including acidification, eutrophication and siltation.

Bullhead are small, spiny fish, common to sections of river where the depth is greater than 5cm, with moderate flow, coarse gravel substrate and <40% macrophytes (Tomlinson and Perrow, 2003). Favoured habitats are usually rivers that are sinuous in form, with pool-riffle sequences, slack water refuges during spate flow, naturally wooded riparian margins and exposed roots in the channel. The substrate at spawning sites is coarse with large stones with very little silt. Bullhead larvae are found in the shallower riffle areas of the channel and adults in sheltered sections where debris, tree roots, macrophytes or large stones provide sufficient cover.

Bullhead are adversely affected by aquatic pollution, habitat deterioration (siltation), fragmentation of populations, changes to flow regime and sediment dynamics and changes in dissolved oxygen levels. Removal of hard substrate, in-channel vegetation and/or riparian trees may be detrimental to bullhead populations by decreasing suitable habitats and increasing exposure to predators. The presence of this species is indicative of good water quality.

The CCW CMP (Dyson, 2008) identifies a number of management requirements for bullhead. These include maintaining the quality of suitable bullhead habitat as elevated levels of fine sediment may impact on eggs and fry. In addition, it is thought that submerged macrophytes play a role in providing cover from predators. Woody debris is important to bullhead, particularly in the lowland reaches where it may be used as alternative spawning sites and protection from floods and predators. Intermittent tree cover (at least 50% channel cover) is important to bullhead. Non- native crayfish are thought to adversely affect bullhead populations.

2.2.6 European Otter (Lutra lutra)

Otter Lutra lutra habitat requirements include potential den/holt sites which are usually under exposed root systems along the river banks (Chanin, 2003). The presence of ash, sycamore, oak and elm often provide such features as the river eroding sediment and substrate from around the roots. Otters favour areas of river with a high amount of cover created by bankside trees, woodland and scrub where

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they may lay up during the day. Otters require access to an adequate resource of prey, which is dominated by fish and also includes amphibians, young birds and small mammals.

The Lugg was selected as an important breeding holt complex in the Herefordshire Area of Search (River Lugg Conservation Strategy, 1996). The Lugg is thought to hold a moderate density of otters and the population may be increasing. In the 1980s, the River Lugg was one of the few rivers in central England to retain a healthy population of otters (River Lugg Restoration Strategy, 1996).

Threats to otter include disturbance through habitat destruction, pollution from agricultural practices, introduced species such as mink Mustela vison increasing competition, predation of otter cubs (etc.), disease (possibly spread by mink), road fatality and acidification lowering fish numbers as a food source.

2.2.7 White-clawed Crayfish (Austropotamobius pallipes)

White-clawed crayfish were thought to be present along virtually the entire length of the River Lugg when assessed in 1996 as part of the River Lugg Conservation Strategy. Anecdotal evidence suggests that since then there has been a major decline of this species in the Wye SAC. However, surveys conducted by the Environment Agency on the 28th August 2014 recorded white-clawed crayfish in the section upstream of Yatton near the mill leat (Throup, 2014). The status of the presence of the white-clawed crayfish in unknown in the Welsh sections of the River Lugg, but is considered to be optimal/favourable in England.

The crayfish species tend to occur in areas with relatively hard, mineral-rich water on calcareous and rapidly weathering rocks. White-clawed crayfish tend to inhabit areas under the cover of rocks, submerged rocks and cobbles, macrophytes, roots of woody vegetation and algae, emerging only to obtain food. Adults may also burrow into the substrate during winter months. The white-clawed crayfish requires an environment with heterogeneous flow types and refuge areas (Holdich, 2003).

There are a number of threats to the white-clawed crayfish. Poaching by stock may increase turbidity and reduce dissolved oxygen concentrations as a result of sediment and excrement entering water, which may be detrimental to the white- clawed crayfish.

American signal crayfish are now also present within the Lugg and Hindwell Brook and are a serious threat to the white-clawed crayfish and are a non-native species. American signal crayfish are able to out-compete white-clawed crayfish and carry crayfish plague (a fungal disease) to which the white-clawed crayfish has no immunity. Crayfish plague may also be carried on fishing gear and boats. There is also evidence of competition between non-native crayfish and native fish species for the use of refuge areas. The key issues along the River Lugg include the crayfish plague, low river flows/drought and habitat modification. The non-native crayfish may also have an impact on invertebrate populations within an area, which may have a direct impact on those fish species that also feed off of invertebrates. Whilst weir removal delivers numerous benefits to river restoration, it also enables signal crayfish to migrate and access stretches of river where native species are currently found.

Pyrethroid sheep dips entering the watercourse may also have a devastating effect on white-clawed crayfish, although it is rarer to have this type of pollution in current

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times. This may happen if recently dipped sheep enter the watercourse or the area where the sheep are being dipped drains directly into a watercourse. Other pollutants that may impact on white-clawed crayfish include organosphosphate sheep dips and chemicals used when repairing bridges. Appropriate pollution prevention methods should be adhered to when carrying out activities near to watercourses.

2.3 SSSI Condition Status

Attributes used to assess the condition of SSSIs and SACs designated for river habitats and species have been agreed by UK conservation agencies and are set out Common Standards Monitoring Guidance for Rivers (JNCC, 2014). Having identified the river types present in a SSSI, the aim is to provide favourable habitat conditions appropriate to that river type for the characteristic biological community, rather than focusing on restoration to benefit a particular species.

The River Lugg (England) SSSI is split into four units, all of which are currently assessed as being of unfavourable recovering condition (Table 2.4). The reasons detailed for the adverse conditions of the SSSI units include fertiliser use, invasive freshwater species, siltation and water pollution from agricultural runoff and discharge (which is likely, in part, to be a result of stock watering/access to the channel issues). Actions or SSSI remedies are underway to address these issues (Table 2.4). The remedies require continued implementation for the site to eventually reach favourable condition and other actions and remedies may also being ongoing in parallel with those provided in Table 2.4. Unfavourable recovering condition suggests that all necessary management measures are currently in place, with the aim of addressing the adverse conditions of the SSSI unit, and if these measures are sustained the site will recover over time.

The Lugg Meanders are also a SSSI within Unit 3 that is currently being assessed as favourable (Table 2.4).

It should be noted that these sites were not designated because of the condition they were in, but were based on best examples of type, with the intention of preventing any further deterioration and, over time, addressing the exiting impacts.

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Table 2.4 River Lugg (England) SSSI units and condition assessment status (condition assessment conducted in 2002)

Location RRP- Remedies underway to English seek funds to Original adverse condition address adverse condition Threats to condition Condition SSSI Unit develop and reasons (need continued (not in priority order) implement implementation) 1 River Lugg Unfavourable Fertiliser use, invasive freshwater ELS, invasive species Water pollution (Wye SAC) recovering species, siltation, physical control programme, DWPP, (delivery and funding modification and freshwater water Integrated Nutrient of CSF/ELS and pollution - agriculture/run off and Management Plan. DWPP delivery). discharge. Invasive species 2 Bodenham Weir Unfavourable Fertiliser use, invasive freshwater ELS, invasive species control plan. to Leominster recovering species, siltation, physical control programme, DWPP, Delivery of actions in modification and freshwater water Integrated Nutrient River Restoration Plan pollution - agriculture/run off and Management Plan. and Nutrient discharge. Management Plan. 3 Leominster to Unfavourable Overgrazing, fertiliser use, ELS, invasive species Recreational risk Mortimer’s recovering invasive freshwater species, control programme, DWPP, (disturbance). Cross siltation, physical modification and CSF delivery, Integrated freshwater water pollution - Nutrient Management Plan. agriculture/run off and discharge. 4 Mortimer’s Unfavourable Overgrazing, fertiliser use, ELS, invasive species Cross to recovering invasive freshwater species, control programme, DWPP, Presteigne siltation, physical modification and CSF delivery, Integrated freshwater water pollution - Nutrient Management Plan. agriculture/run off and discharge. River Eyton Favourable Features visible and intact. Natural Fluvial processes unconstrained. Natural erosion may Lugg soon mean some fences will need moving. Meanders

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Although water quality (e.g. diffuse pollution) is an important contextual issue to consider in the development of a Restoration Vision it is not part of this current study and is being addressed elsewhere (e.g. as part of WFD actions). It is also useful to cross-reference the condition assessments given in Table 2.4 and Table 2.5 with the WFD hydromorphological status of the relevant water bodies in Table 2.6.

2.4 SAC Condition Status

CCW6 has assessed the condition of each SAC feature at whole river scale, rather than on a management unit basis. From these condition assessments, it is anticipated that a large number of the Welsh management units will be in unfavourable condition. The River Wye SAC is approximately 2235ha and encompass the River Lugg from its confluence with the Wye to Hope-under-Dinmore (SSSI Unit 1).

The features that make up the SAC have been assessed using performance indicators set against an overall vision for the feature to be in favourable condition. Table 2.5 shows the condition status for each SAC feature and the management units that cover the River Lugg that should be managed for this species (based on Hatcher and Garrett, 2008). The SAC features are attributed to each management unit as either a Key Species (KS) or Key Habitat (KH) for which each management unit should be specifically managed.

Table 2.5 River Wye SAC features and condition status (Dyson, 2008) Condition Key species Reason for condition Status 1. Watercourses of Unfavourable: Reduced water quality possibly from plain to montane unclassified diffuse pollution from agriculture and levels with the prevalence of Japanese knotweed and Ranunculion Himalayan balsam. fluitantis and Callitricho- Batrachion vegetation 2. Sea lamprey Favourable: Meets JNCC targets and Harve and (Petromyzon unclassified Cowx (2003) suggested targets. marinus) 3. Brook lamprey Unfavourable: Although JNCC ammocoete targets met, (Lampetra planeri) unclassified CCW (now NRW) Catchment Management Plan (CMP) targets failed. More surveys are required. Difficult to distinguish between river lamprey in field. 4. River lamprey Unfavourable: Although JNCC ammocoete targets met, (Lampetra fluviatilis) unclassified CCW (now NRW) CMP targets not met. More surveys are required. Difficult to distinguish between brook lamprey in field. 5. Twaite shad Unfavourable: Precautionary assessment of feature (Alosa fallax) unclassified abundance and presence of adverse factors including flow depletion and

6 As of 1st April 2013 Natural Resources Wales (NRW) took over the functions of the CCW

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Condition Key species Reason for condition Status entrainment in water intakes. 6. Allis shad (Alosa Unfavourable: Precautionary assessment of feature alosa) unclassified abundance and presence of adverse factors including flow depletion and entrainment in water intakes. 7. Atlantic salmon Unfavourable: Failure of adult run size management (Salmo salar) unclassified target. Presence of adverse factors including flow depletion and localised water quality failures. 8. Bullhead (Cottus Unfavourable: Presence of adverse factors, particularly gobius) unclassified localised water quality failures (although Bullhead thought to be widespread). 9. European otter Favourable7 NE (2010) assessed there to be good (Lutra lutra) riparian habitat and otter populations at capacity. 10. White-clawed Unfavourable: Anecdotal evidence suggests major crayfish declining decline of this species. Now confined to (Austropotamobius small areas of Wye catchment. Most pallipes) recent assessment determined them to be in ‘unfavourable condition’.

2.5 Water Framework Directive

Improvements to the condition of the SSSIs and SAC are required both by the Habitats Directive and the Water Framework Directive (WFD). As the downstream extent of the River Lugg (south of Hope-under-Dinmore) is an SAC, the site must meet its SAC and WFD objectives by 20158. It should be noted that this river restoration strategy is be part of a catchment scale approach and other projects, each targeting a particular issue, will provide a holistic catchment management strategy.

The River Lugg falls within the Severn River Basin District (RBD) in the Wye Management Catchment. To meet the WFD objectives and address the pressures on the water bodies, a River Basin Management Plan (RBMP) has been created for each RBD. As part of the Severn RBMP, Annex C provides a summary of a programme of investigations undertaken by the Environment Agency to improve our understanding on why certain water bodies are failing their WFD objectives and what actions could be taken to improve the status. A range of issues have been identified and some of the actions are as follows:

 Improve access and habitat quality for fish (specifically on the River Lugg);  Reduce physical modification and diffuse pollution through practical actions (such as fencing and buffer strips) and remove fish obstruction; and,  Weir removal of Environment Agency owned structures, where appropriate.

7 CCW (2008) (now NRW) assessed otters to have lack of suitable habitat in the middle reaches of river and have assessed the condition as unfavourable 8 Note: the dates for achieving the WFD objectives may change when the next cycle of River Basin Management Plans are available.

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The RBMP sets out what improvements are possible by 2015 and 2027 and how the actions will make a difference to the local environment. The plan also highlights a programme of investigations to be undertaken, identifying further actions (particularly those associated with diffuse pollution), for delivery during the first cycle. Actions incorporate raising awareness of catchment issues through education and advice campaigns and guidance forums, statutory codes of practices and best practices, byelaw enforcement and environmental reviews and studies.

The River Lugg comprises a total of five WFD water bodies, two of which are in England and will be focused on as part of this study. The detail of the WFD assessment for the two water bodies is provided in Table 2.6. The River Lugg – confluence River Arrow to confluence River Wye is at poor ecological status and has to achieve good ecological status by 2027 through a programme of mitigation measures. The River Lugg – confluence Norton Brook to confluence to River Arrow is at good ecological status. The reason the River Lugg – confluence River Arrow to confluence River Wye is failing to achieve GES is predominantly a result of the fish status (poor). All other quality elements for the water body are assessed as high or good. The morphology of both water bodies is assessed to ‘Support Good’ ecological status. Although morphology and the quantity and dynamics of flow have been allocated ‘Supports Good’ status, addressing pressures in the Lugg catchment will have beneficial effects on the hydromorphology of the river, which will also benefit the SSSI and SAC features.

SAC rivers, such as the River Wye (including the River Lugg unit), are classed as Protected Areas under Article 6 of the WFD. As such, the location and status of the River Wye water bodies are outlined in the main Severn RBMP, and also measures to address pressures on the water bodies are given in Annex D of the RBMP. Where the SAC objectives are higher than WFD objectives, the SAC objectives must be met. The standards to achieve SAC/SSSI objectives are typically higher and assessments more detailed so, for example, where morphology under the WFD is considered to ‘Support Good’ this is not always considered to be suitable for the SAC/SSSI objectives. This means that the Wye SAC could achieve good ecological potential or status, whilst not achieving favourable condition.

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Table 2.6 Water Framework Directive assessment for the River Lugg (England) Element Water Body Water Body ID GB109055036790 GB109055042030 Water Body Name R Lugg - confluence River R Lugg - confluence Norton Arrow to confluence River Wye Brook to confluence River Arrow Water Body Length 44.8km 40.5km Management Wye (98) Wye (98) Catchment Hydromorphological Not Designated Not Designated Status Overall Ecological Poor Status Good Status Status Predicted Status Good by 2027 Good status by 2015 Objective High chemical status by 2015 Protected Area SSSI SSSI Designation Biological Quality Elements Fish Poor No data Macro-Invertebrates High High Physico-chemical Quality Elements Current Chemical Does Not Require Assessment Good Quality Hydromorphology Quality Elements Quantity and Supports Good Supports Good Dynamics of Flow Morphology Supports Good Supports Good

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3 Method

3.1 Overview of Method

A desk based assessment was undertaken that reviewed a number of reports and studies previously carried out on English SSSIs along the River Lugg, including the River Lugg Restoration Project and various River Habitat Surveys carried out from 1994 to 2007. The desk based assessment has been undertaken in line with the Natural England river restoration planning guidelines. The desk study was used to identify further survey work required.

A combination of spot checks and fluvial audits (of specific reaches only) were undertaken on parts of the River Lugg to summarise sections of the river. The fluvial audit approach was originally developed in parallel with the Guidebook of Applied Fluvial Geomorphology (Sear, Newson and Thorne, 2009). Fluvial audits may be tailored to the specific objectives of a project and have been applied in a wide range of circumstances. In this case, the method was amended to investigate potential restoration options for the River Lugg. Spot checks were also carried out in places to provide a general overview of the geomorphology, hydrology and ecology of a strategically selected section of the river ranging from 250m to 1km. Data on land use and soils on the adjoining floodplain were also collected to inform the analysis and restoration options. This information is used to indicate the vulnerability of the soils to erosion processes, which may result in increased sediment loading within the channel. The presence of invasive species (Himalayan balsam, Japanese knotweed and giant hogweed) was also recorded; however, due to seasonality of the surveys the occurrence of invasive species is likely to have been underestimated. Evidence of phytophthora was also noted; however, identification was impaired due to the timing of the surveys.

A total of 8 bespoke fluvial audits and 22 spot checks were carried out along the Lower River Lugg. Each of these stages is described in more detail below.

3.2 Desk Based Assessment

The desk study involved a review of catchment scale datasets such as topographic, geological and historical maps, aerial photographs, previous studies on the River Lugg and previous geomorphological and ecological surveys carried out on the Lugg. These included:

 River Lugg Restoration Project: Development of an ecologically based vision for the River Lugg SSSI (2010);  River Lugg Conservation Strategy (1996);  Conservation objective and definitions of favourable condition for designated features of interest (2012);  Severn River Basin District RBMP (2009), Environment Agency;  River Lugg Internal Drainage Board: Biodiversity Action Plan (2010);  Core Management Plan for River Wye Special Area of Conservation (2008); and,  River Lugg River Habitat Survey data (1994-2007).

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The desk study has also involved a review of Dr. Niamh Burke’s PhD thesis entitled ‘Physical controls on salmon spawning habitat quality and embryo fitness: An integrated analysis’. Dr. Niamh Burke works for Jacobs and has informed the assessment. Information from the British Library archives has also been obtained to provide background information on river catchment works and historical modifications to the river.

In addition to the above sources, Wheeldon et al. (2010) guidelines for SSSI river restoration and JNCC common standards monitoring guidance for rivers (JNCC, 2014) were followed throughout this study and river restoration planning process.

3.3 Field Survey

3.3.1 Overview

Field surveys were undertaken on the 15th January 2014, between 26th February and the 28th February 2014 and between the 6th October and 8th October 2014, covering approximately 30km of river. The sites surveyed were targeted following a gap analysis after the completion of the desk study of existing data and information and the review of some existing datasets for the River Lugg. The field surveys, undertaken by geomorphologists, comprised bespoke fluvial audits and spot checks (please refer to Section 3.4 for locations). All observations were made using professional judgement and prior experience of similar river types. Figure 3.1 shows the surveyed area of the River Lugg and those areas covered by previous River Habitat Surveys.

The bespoke fluvial audits focused on recording and mapping the following types of information based on visual observations at the time of survey:

 Sediment sources (erosion) and sinks (deposits);  Bed and bank composition;  Characteristics of the riparian zone;  Channel modifications (straightening, deepening, bank reinforcement, weirs);  Point sediment sources (such as tributaries);  Dominant geomorphological function and processes (such as erosion);  Conservation status;  Sediment and predominant flow types;  Habitat suitability for designated SAC and SSSI habitats as well as species; and,  Presence of important channel features/habitats with subsequent consideration for designated species (such as woody debris and vegetation stands).

Walkover surveys recorded the degree of modifications to the channel and its surrounding environment as well as the processes occurring upstream and downstream of that reach. Both of these form a key determinant as to the requirement for and type(s) of physical restoration. Assessment of the channel morphology and dominant geomorphological processes, alongside the ecological habitat suitability for feature species, enables determination of physical habitat restoration options. Consideration is then given as to whether such restoration would result in the reinstatement of river function and form, i.e. suitable habitat and associated ecological gain or improvement and for given species (or species specific life stages).

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The primary reach function (i.e. sediment source, transfer, exchange or sink) were categorised for each surveyed area along with the geomorphological processes (see Table 3.1 and Table 3.2 respectively). The classification of reach function is based on the geomorphological conditions observed at the time of survey and knowledge from previous surveys and studies.

Table 3.1 Reach function definitions (adapted from Sear, Newson and Thorne, 2009) Reach Function Description Sediment source Sediment output from the reach is greater than sediment supply from upstream Sediment transfer Sediment output is approximately equal to input from upstream. Sediment is transmitted through the reach, which features few sites of active erosion, or deposition either because the channel is adjusted and naturally stable or because the bed and banks have been stabilised artificially Sediment exchange Sediment output is approximately equal to input from upstream (as for a transfer reach), but incoming sediment is exchanged with that derived within the reach, which features active erosion and depositional sites Sediment sink Sediment input to the reach is greater than sediment output to the next reach downstream Winterbourne Flow expected only at high flow, therefore the balance of sediment inputs and outputs is seasonally dependent

Table 3.2 Field indicators of instability and stability – reach process (adapted from Sear, Newson and Thorne, 2009) Category Indicators Category Indicators

Incising Perched boulder berms Aggrading Buried structures Terraces Buried soils Old channels Large uncompacted point Old slope failures bars Undermined structures Eroding banks at shallows Exposed tree roots (both Contracting bridge space banks) Deep fine sediment over Armoured/ compacted bed coarse gravels in bank Deep gravel exposure in Many unvegetated point banks that are topped with bars fines Large silt/clay banks Widening Bank failures (both banks) Laterally Significant number of bank Vegetation falling in, or adjusting erosion areas leaning towards the Significant number of bar channel on both banks formation areas Evolution of a new Channel cut-offs planform at a lower elevation Stable Vegetated bars and banks Narrowing Sedimentation on both Compacted weed covered channel margins bed. Bank erosion rare Old structures in position

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The modification score (based on Sear, Newson and Thorne (2010) conservation status) of each reach was determined during the bespoke fluvial audits and spot checks. Table 3.3 provides the description of each level of modification score and is based on the degree of modification present within that reach and the level of recovery of the geomorphological features. This was used along with the bespoke fluvial audit data collected to identify and prioritise potential restoration opportunities. These modification scores will subsequently feed into the development of river restoration categories within the proposed restoration strategy.

Table 3.3 Modification Score and Descriptions (based on the conservation status developed by Sear, Newson and Thorne, 2010) Modification Score Description Score High 8-10 Conforms most closely to natural, unaltered state and will often exhibit signs of free meandering and possess well-developed bedforms (point bars and pool-riffle sequences) and abundant bank side vegetation Moderate 5-7 Shows signs of previous alteration but still retains many natural features, or may be recovering towards conditions indicative of the higher category Low 2-4 Substantially modified by previous engineering works and likely to possess an artificial cross-section (e.g. trapezoidal) and will probably be deficient in bedforms and bankside vegetation Channelised 1 Awarded to reaches whose bed and banks have hard protection (e.g. concrete walls or sheet piling) Culverted 0 Totally enclosed by hard protection Navigable - Classified separately due to their high degree of flow regulation and bank protection, and their probable strategic need for maintenance dredging

Raw geomorphological and ecological field data and photographs taken during the bespoke fluvial audits were collected using a hand-held mobile mapping device. The mobile mapping device allows the data to be input directly into a Geographical Information System (GIS) for subsequent analysis and comparison with other datasets. In addition, sweep up sheets were used to help characterise reaches within each bespoke fluvial audit.

Spot checks, ranging from 500m to 1km in length, were strategically selected during the desk study. The centre points of these spot checks were usually marked by a road bridge. These allowed for more of the river to be seen in a shorter space of time in comparison to fluvial audits (of specific reaches determined through gap analysis only). The aim of the spot checks was to characterise the river along the selected length for aspects including river channel planform and dimensions, floodplain, bed and bank materials and riparian zone. Photographs and major structures/modifications were recorded on a paper map and digitised onto the interactive mapper tool.

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3.3.2 Definition of a Geomorphological Reach

The river was sub-divided into ‘reaches’ to organise the data collected during the fluvial audits and spot checks, and to facilitate the development of outline restoration plans for the SSSIs and SAC. The reaches were defined using information from both the desk study (using aerial photography) and the fieldwork (i.e. site knowledge). These reaches represent sections of the river which indicated a change in the specific geomorphological and ecological characteristics as well as a variation in the surrounding land-use types. Reach names are coded in the following way: LUGG001, LUGG002, LUGG003 etc.; a new reach number was allocated where the character of the river and its surroundings changed. Reasons for defining a new reach consisted of a combination of the following:

 Appreciable change in the morphology of the channel, such as a change in planform or cross-sectional form;  A change in the dominant fluvial process and function;  Change in the composition and condition of the riparian zone;  Change in dominant land use;  Change in tree lining and riparian buffer zone; and,  Presence of in-channel structures (e.g. weirs).

When assigning sections of river to particular reaches and also during individual spot checks/bespoke fluvial audits, emphasis was placed on the need for restoration and the potential nature of this restoration. Additionally, potential elevated supply of sediment from land use and surface runoff was also recorded for each reach.

Some RHS data were available for sections along the River Lugg, primarily focused around Bodenham and Lugwardine. This data has been used in addition to Jacobs (2014) site information. Restoration measures have not been based solely on the RHS data due to the low coverage and the age of the records (1994-2007). RHS data analysis is supported by the Jacobs (2014) spot checks and bespoke fluvial audits for the determination of restoration measures.

3.4 Study Area

The study area for this investigation was the Lower Lugg from Presteigne to the confluence with the River Wye. The stretches of river targeted and surveyed for fieldwork are presented in Table 3.4 and Error! Reference source not found. below.

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Table 3.4 Location of walkover survey and spot checks along the River Lugg Identification Survey type Location code SP001 Spot Check Centre point – Presteigne Lugg Bridge (SO316 646) SP002 Spot Check Centre point – Lower Kinsham (S349 641) SP003 Spot Check Centre point – Shirley Farm Bridge (SO380 652) SP004 Spot Check Centre point – Upper Lye (SO398 654) SP005 Spot Check Centre point – Ballsgate Common (SO417 660) SP006 Spot Check Centre point – Mortimer’s Cross (SO426 636) SP007 Spot Check Centre point – Lugg Green weir (SO444 622) SP008 Spot Check Centre point – Lugg Green bridge (SO448 621) SP009 Spot Check Centre point – Leominster (SO500 595) SP010 Spot Check Centre point – Leominster (SO499 594) SP011 Spot Check Centre point – Leominster (SO503 589) SP012 Spot Check Centre point – Eaton (SO507 584) SP013 Spot Check Centre point – Hope-under-Dinmore (SO514 528) SP014 Spot Check Centre point – Bowley (SO536 521) SP015 Spot Check Centre point – Bodenham (SO534 511) SP016 Spot Check Centre point – Bodenham church (SO529 508) SP017 Spot Check Centre point – Marden (SO511 471) SP018 Spot Check Centre point – Marden church (SO512 470) SP019 Spot Check Centre point – Moreton Bridge (SO513 460) SP020 Spot Check Centre point – Wergins Bridge (SO528 446) SP021 Spot Check Centre point – Lugg Bridge (SO531 418) SP022 Spot Check Centre point – Lugwardine Bridge (SO545 406) FA001 Fluvial Audit Presteigne – from SO309 651 to SO311 648 FA002 Fluvial Audit From Combe (SO354 636) to Lower Kinsham (SO 362 645) FA003 Fluvial Audit Beechenbank Wood (SO418 658) to Yattons Court (SO421 655) FA004 Fluvial Audit Yatton Court (SO424 655) to Aymestrey (SO427 652) FA005 Fluvial Audit From Eyton (SO464 612) to Leominster (SO501 595) FA006 Fluvial Audit Wheelbarrow Castle – from SO513 571 to SO512 566 FA007 Fluvial Audit Wharton (SO509 551) to Marlbrook (SO511 547) FA008 Fluvial Audit Lugwardine (SO545 406) to Mordiford (SO565 370)

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Figure 3.1 Site locations covered by the January/February and October 2014 surveys and the River Habitat Surveys (1994-2007)

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The river was sub-divided into 26 reaches within the study area based on the desk study information and spot checks/bespoke fluvial audits (Figure 3.2). The reaches are shown in Table 3.5 and it has been indicated whether these were defined using spot checks/bespoke fluvial audits or by desk study information.

Table 3.5 Reach locations following completion of the desk study, spot checks and fluvial audits Reach SSSI Reach description Determined by code nit spot check (SP)/fluvial audit (FA) desk study Start Unit 4 England/Welsh border – Presteigne. Desk study only Reach through Presteigne punctuated by 4 minor weirs. Desk study/FA001/ Some bank reinforcement. Land use: SP001 LUGG001 pasture/ urban-suburban. LUGG002 Middlemoor to boundary of woodland at Kinsham.

Land use: Pasture dominated to arable Desk study/ dominated. Actively meandering SP002/FA002 sections with naturally eroding banks and depositional features. Lack of riparian corridor. LUGG003 Lower Kinsham to Upper Kinsham.

Desk study/ River flows through wooded section, FA002 with naturally eroding banks and depositional features. LUGG004 Meanders at Byton to Lyepole weirs.

Desk Dynamic planform with steep naturally study/SP003 eroding banks, and depositional features. LUGG005 Lyepole weirs to Amestrey weir.

Desk Gravel-bedded river section through study/SP004 gorge. Good flow diversity, shading and general habitat. LUGG006 Unit 3 Amestrey weir to Yatton court weir. Gravel-bedded river section through gorge. Good flow diversity, shading and Desk general habitat. Good variation in study/SP005/ depositional features and areas of FA003/FA004 naturally eroding bank. Secondary channel provides greater habitat heterogeneity. LUGG007 Yatton Court to Mortimers Cross weir.

Desk Gorge-like but straighter section, study/SP006 adjacent to road. Wooded on one bank with some depositional features.

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Reach SSSI Reach description Determined by code nit spot check (SP)/fluvial audit (FA) desk study LUGG008 Mortimers Cross to Lugg Meanders. Desk study/ Land use: Pasture and arable SP006-- dominated. Some depositional features 008/FA005 and eroding banks. LUGG009 Lugg meanders 1.

Section with good flow diversity active Desk study/FA005 planform but fairly intensive arable and pasture riparian land use. LUGG010 Lugg Meanders 2.

Desk study/FA005 Short section river flowing within wet woodlands. LUGG011 Lugg Meanders 3. Desk study/FA005 Section between two weirs. LUGG012 Unit 2 Weir at Mousenatch to Kenwater weirs.

Desk study/FA005 Reach just before Leominster town. Highly modified for flood defence. LUGG013 Kenwater weir to The Marsh. (Section through north Leominster). Desk study/FA005

Highly modified for flood defence. LUGG014 The Marsh (Leominster) to Eaton. Desk

study/SP009-012 Highly modified trapezoidal channel. LUGG015 Eaton to Wharton.

Desk study/FA006 Land use: Pasture/arable. Intermittent riparian corridor. Uniform channel. LUGG016 Unit 1 Wharton to Marlbrook

(also Modified section with bank Desk study/FA007 part of reinforcement on the right bank due to the the A49. Limited features. LUGG017 River Marlbrook to Hope under Dinmore. Wye Desk SAC) Uniform section with some wooded Study/SP013 sections. LUGG018 Hampton Court Weir – Bowley. Desk study only LUGG019 Bowley to Bodenham.

Desk Section through intensive arable land study/SP014-015 with little buffer strip and thin riparian cover. LUGG020 Bodenham to the railway bridge to the Desk west. study/SP015-016

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Reach SSSI Reach description Determined by code nit spot check (SP)/fluvial audit (FA) desk study Steep vertical banks, some depositional features and naturally eroding banks. LUGG021 Section of river west of the railway near Desk study only Green Farm. LUGG022 Train crossing to Moreton bridge.

Desk Uniform channel. Sections of the river study/SP017-019 are embanked, particularly around Marden. LUGG023 Moreton Bridge to Sutton St. Nicholas.

Desk study only Section through woodland, with good planform and some shading. LUGG024 Wergins bridge to Shelwick green. Desk Good planform and geomorphologically study/SP020 active. LUGG025 Shelwick to Lugg Bridge.

Desk Set back embankments on both banks. study/SP021 Uniform channel, some depositional features. LUGG026 Lugg Bridge to Mordiford.

Good planform and geomorphologically Desk study/ active. Naturally eroding banks with SP021- depositional features. Vertical banks 022/FA008 reducing floodplain connectivity in low flows. Some sections have set back embankments.

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Figure 3.2a Reach locations along the River Lugg

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Figure 3.2b Reach locations along the River Lugg

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3.5 Data Analysis and Reporting

The findings of the desk study and field survey data are presented in this report. The raw geomorphological data recorded using the mobile mapper are in GIS format and may be viewed using the interactive mapper tool on the CD accompanying this report. The photographs taken during the 2014 survey are also geo-referenced in the interactive map.

The potential restoration options for the River Lugg are outlined in the accompanying Management Report. This sets out a vision for the long term restoration of the SSSIs and SAC and provides a series of potential reach-by-reach proposals. Any potential restoration options developed will then need to be taken to consultation with the appropriate landowners. Stakeholder engagement will be encouraged throughout the development of these options to ensure local needs are met. Following this, detailed proposals may be developed focusing on specific locations.

3.6 Limitations and Assumptions

The scope of the project is to produce a restoration strategy for the Lower Lugg including surveying approximately 30km of the River Lugg. The total length of river making up the designated English SSSIs is approximately 74km.

Limitations of this study relate to data availability and gaps in the fieldwork. There are still areas of the River Lugg that have not been surveyed by a geomorphologist, and instead have been assessed using aerial photography, OS maps and by driving alongside sections of the river (although this is limited due to access to the river).

Aerial photography may distort the proportions of the river, and not all pressures are necessarily captured. Similar to one time site visits, rather than repetitive surveys during different seasons and flow events, aerial photography only captures the river at one point in time. For example, land use changes which may occur frequently, may not represent the current land use at the time of reporting.

Restoration visions are based on a combination of field data collected for this current survey, aerial photographs and OS maps and River Habitat Survey data. As a result it is assumed that the restoration visions may be applied elsewhere in the catchment to non-surveyed areas based on the broad catchment understanding gained from the surveyed reaches.

A number of limitations were identified with conducting field surveys during late winter. During January and February 2014 the Lugg catchment was subject to significant rainfall and high river levels. As such, it is likely that some, otherwise important marginal or mid channel geomorphological features such as side bars, berms and areas of erosion were partially or fully obscured by water levels. Seasonality for ecological receptors was a further limitation, as most of the riparian and aquatic plants had died back. Therefore the full extent of riparian zone and aquatic plants may be underestimated. This limitation has been recognised and accounted for in the analysis of field data.

The high river levels in January and February 2014 surveys also restricted visibility of modifications, in particular bank toe modification such as reinforcement. Consequently, bank modification, in particular at the bank toe, is likely to be under- recorded.

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In addition, the full extent of invasive species such as Japanese knotweed and Himalayan balsam may also be obscured as much of these had also died back at the time of survey. Himalayan balsam is known as a problematic invasive non-native species along the River Lugg and is identified as one of the reasons for unfavourable recovering condition in SSSI Units 1-4. An invasive non-native species control programme is one of the remedies for improving the condition status of SSSI units. Further information on invasive species and their management and control is provided in Section 4.10.4.

Spot checks completed in October 2014 revisited some of these sites to enable a comparison of the river channel in high winter flows and lower autumn flows through photographs to create a more comprehensive dataset.

This study only covers the Lower Lugg from Presteigne to the confluence with the River Wye, which poses a limitation in terms of producing reach plans. A separate restoration strategy is being developed for the Upper Lugg in Wales, commissioned by Natural Resources Wales. The overall aims and objectives of the Upper Lugg and Lower Lugg studies differ, which is an additional limitation. It is important to note that the catchment context will be taken into consideration for the restoration options developed within this restoration strategy, but no restoration options or detailed assessment of the Upper Lugg will be provided. Upstream pressures may be having downstream impacts that are not captured in this report. However, previous studies have been completed on these upstream sections and have been used in the analysis to provide background information where applicable. This report is a draft for consultation and does not represent a final restoration vision and strategy. Once the report has been updated following consultation, ways of linking the restoration strategies for the Upper and Lower Lugg may be explored.

3.7 Developing the Restoration Vision and Detailed Plans

The potential restoration plans have been developed using a combination of:

 Geomorphological and ecological expertise regarding the type of characteristics the river channel and its surrounding environment should exhibit under natural conditions and the use of this expertise to determine the level of habitat degradation from channel modification;  An understanding of the requirements to meet ecological indicators for feature species and the link between habitat suitability and feature species;  An understanding of how other pressures such as flow regulation may be impacting upon the river channels in parallel with morphological pressures;  Guidance on best practice for management of rivers and their surroundings; and,  Review of widely used river restoration techniques including a consideration of their suitability.

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4 Catchment Characteristics

4.1 Catchment Overview

The Lugg is a cross-border catchment with its source near Pool Hill in Powys, Wales. It flows across the Welsh-English border beyond the town of Presteigne, into the county of Hereford where it flows through Leominster and then southward to its confluence with the River Wye near Mordiford. The River Lugg is the largest tributary of the River Wye (approximately 101km) with the River Arrow as its main tributary. . The Lugg has a catchment area of 1077km² to its confluence and is characterised by both upland and lowland river types.

4.2 Geomorphological Background

The River Lugg is considered to be one of the best British mainland examples of both a clay river and a river displaying a transition from nutrient-poor to naturally nutrient-rich water chemistry (River Lugg Restoration Strategy, 1996).

4.2.1 Geology in the Lugg Catchment

The Lugg catchment is generally described as impervious in its upper reaches transitioning to sandstone geology further downstream. It holds extensive valley gravels and sands providing some base-flow and moderation of flood peaks during high rainfall events (Marsh and Lees, 2003, Wade et al., 2007).

From the source, the river drains an upland area (including Radnor forest) which is underlain by Silurian mudstones and siltstones. The bedrock geology is the dominant influence on channel form in the River Lugg catchment. Numerous small springs feed the headwaters, combining to cut a steep-sided and rock-bottomed section of river, descending over 200m in the first 3km. The upper catchment of the River Lugg is underlain by Silurian rocks and the river tends to have a high-energy erosive character.

From the border with England at Presteigne, the underlying rock is predominantly non-calcareous and is principally Old Red Sandstone of Devonian age (Figure 4.1). There is some limestone outcropping at Aymestrey Gorge. The presence of the old Red Sandstone is thought to help moderate high flow peaks during wet weather events.

Changes in bedrock and river gradient are reflected in the channel substrate. Alluvial deposits are laid along the riparian zone upstream of Aymestrey Gorge and some glacial moraine deposits are evident in the area around Leominster. Till is further dotted about the catchment in a southwest to northeast direction and may contribute to minor aquifer sources. Along the section from the English/Welsh border to Leominster the average flow is fast, with a well-developed pool and riffle system and a river bed predominantly of cobble, pebble and coarse gravel.

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Figure 4.1 River Lugg catchment geology with drift geology (Source: BGS)

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4.2.2 Soils within the Lugg Catchment

The soils in the upper catchment are dense with medium to low permeability (Figure 4.2). Some alluvium and glacial sands and gravel occur in places along the river channel. There are three main soil types associated with the Lugg catchment, these include the following series:

 Munslow (typical brown earths) – derived from siltstones, has a silty texture and is particular to this region.  Teme (alluvial soils) – a medium silty river alluvium that carries with it a risk of flooding and erosion.  Escrick (argillic brown earths) – a reddish sandy loam which is associated with the underlying old red sandstone. It is particular to this region.

The lower section (within the proposed study area for this report) mainly consists of loamy and clayey floodplain soils with naturally high groundwater. This soil is naturally wet and drains to local groundwater feeding into the river system. Due to the close proximity to the river, there is risk of pollution from floodwater scouring and from drainage water after spreading of fertiliser or slurry. Some areas of the catchment also consist of slightly acid loamy and clayey soils with impeded drainage which drains to the nearest stream network.

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Alluvial GreyGrey soils

Figure 4.2 Soils map of the Lugg catchment (adapted from BGS detailed map)

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4.2.3 Sediment Transport Characteristics

As with any catchment the River Lugg may be divided into three components based on sediment characteristics (see Figure 4.3); these are as follows: sediment supply (sources), sediment transport (or transfer) and sediment storage (sink). These operate as a continuum from the headwaters to the estuary (where a different sediment system operates). The dominance of supply, transport or storage does not occur uniformly over a stream bed or along banks resulting in a range of different river morphologies (types):

1. Sediment supply to the channel is potentially derived from a range of sources, natural erosion of river bed and banks and anthropogenic sources, such as soil erosion resulting from land use management across extensive tracts of the catchment. During the spot check/bespoke fluvial audits, the recent high rainfall had resulted in very silty waters primarily due to sediment being channelled into the river from field runoff and overland flow. This suggests that the Upper Lugg is a major source of fine sediment to the Lower Lugg. 2. Sediment transport or transfer occurs when the stream energy is sufficient to overcome the resistant forces acting on particles comprising the stream bed and/or banks. Sediment transport may be usefully divided into suspended load (silts, clays and fine sands) and the bed load (dominated by gravels and cobbles). During the spot checks/bespoke fluvial audits, most of the Lower Lugg was identified as being a sediment transport zone. 3. Sediment storage may be observed in the form of siltation/shoaling and depositional features such as bars and berms. Deposits may be short term (e.g. a period of low flows leading to the temporary accumulation of sediments as bars) to long term deposits, such as floodplain deposits that are only reactivated in a large magnitude flood. Where sections are embanked or where the river is confined by its narrow valley and floodplain is limited, high levels of sediment are contained in the channel.

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Steep Upland Waterfalls Sediment Supply Zone Bedrock and exposed boulders

Riffles

Localised channel braiding

Moderate gradient Piedmont Exposed sediment deposits Sediment Exchange Zone Woodland corridor along steep tributaries

Erodible Zone allows riparian woodland regeneration Riparian zone

Moderate to low Sediment Transfer Zone Backwater

Riffles River and floodplain connected

Low gradient Pools

Lowland Sediment Storage Zone Point bar Vertical cliffs

Slower flow glides with marginal plants

Figure 4.3 Sediment transport characteristics of upper, middle and lower zones, the Lower Lugg comprises of areas with a low gradient

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4.3 Land Use

Land use in the Lugg catchment mainly consists of pasture and arable production. Grassland and woodland dominate the upper part of the catchment, with some woodland and increasing arable production towards the mid to lower reaches (Lord and Anthony, 2000). In terms of livestock, sheep dominate in the upper parts of the catchment with increasing cattle production in the middle and lower reaches. Additionally, some pig and poultry production is seen mainly in the Arrow sub- catchment and the Lugg below Leominster (Wade et al., 2007).

In the Lugg catchment, there has been an increase in arable farming, with a gradual land use changeover from grassland to arable. Current land use within the Lugg includes various high risk crops such as potatoes, maize, grazed root crops and soft fruit. These crops are considered high risk as they can lead to an increase in sediment transport due to areas of exposed bare soil and the intensive nature of the agricultural practices. It is anticipated that the hectarage of high risk crops is unlikely to reduce. For some crops, the hectarage will stay the same but become more intensive (e.g. soft fruit where there has been a shift to table top production allowing for permanent sites and more investment in infrastructure in comparison to rotational polytunnel sites). Grazed root crops may also become intensive where livestock enterprises are expanding. These intensive units will often extend the grazing season reduce housing costs. The number of anaerobic digesters being built in the catchment will result in additional maize and fodder beet being grown as feedstock. The hectarage of potatoes is slowly reducing; however, where they are no longer being grown it is often being replaced by maize. Where potatoes remain, the need for fresh ground often pushes them further upslope, which increases the risk of soil erosion and consequent sedimentation. It is estimated that an increase in maize production of up to 15,000 hectares will occur over the next 10 years within the Lugg catchment (Pers comm: H Probert, Wye and Usk Foundation).

0 10 20 Kilometres

Figure 4.4 Land use on the River Lugg (Source Centre for Ecology and Hydrology (CEH))

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Table 4.1 indicates land use proportions within the Lugg catchment.

Table 4.1 Land use in the Lugg catchment (CEH, 2012)

Descriptor Byton Leominster Lugwardine National Grid Reference SO364 646 SO502 589 SO548 405 (Butts Bridge) Catchment Area of gauge (km²) 203.3 371 885.8 Land cover (%) Woodland 11.6 12.3 11.4 Arable/horticultural 6.4 17.5 26.2 Grassland 73.3 63.3 56.0 Mountain/Heath/Bog 5.9 3.4 2.8 Urban Extent 0.1 0.4 0.5

The Severn District River Basin Management Plan (RBMP) (2009) highlighted problems of sedimentation within the Lugg catchment. It states that all watercourses in the area around Leominster were shown to be at risk from diffuse inputs of sediment following rainfall events. Evidence of other factors that may contribute to diffuse inputs such as bank erosion, narrow buffer strips, lack of secondary vegetation and lack of livestock fencing were also reported.

4.4 Sci-Map Outputs for the Lugg Catchment

The Wye and Usk foundation provided outputs from the Sci-Map model, developed by Durham University, to inform the understanding of how the catchment topography and land use influence the current and potential future land surface erosion and potential sediment delivery risk within the catchment. These included an overview of two scenarios of sediment delivery risk to the main-stem Lugg catchment. Sci- Map calculates the risk of sediment erosion and delivery to the channel, based on the land surface inclination and land use – whether unimproved pasture, arable production, forested areas or other. The varying land use types will be associated with an attributed ‘risk factor’ which will be coupled with the existing topographic risk factors based on land surface slope relative to the river.

Additional delivery routes within the land surface due to man-made changes or land management practices (such as field drains or tillage direction in arable fields) may incur additional risk, but which will not be evident without in-field examination. This is something the Wye and Usk Foundation are presently working on in conjunction with individual land owners within the catchment. Work on this high resolution risk aspect is still ongoing for the Lugg catchment. Once the field data has been collected, it may be fed into the model. This will provide a more precise picture of risk based on current land-use and farm management practices, and may form a basis for advising landowners on infrastructure (e.g. slurry storage, silage clamps, clean/dirty water separation, track ways) to reduce the risk posed or connectivity to the nearby watercourses. Figure 4.5 highlights the key risk areas as defined by Sci- Map model based on Land cover data 2007 provided by CEH, which may not fully represent the current land-use as is (in 2014).

Figure 4.6 represents the catchment sediment erosion risk based on an ‘all-arable’ land use scenario. In this scenario, there are increased erosion risk areas compared to the model run based on 2007 land-cover data. Although this is not a realistic scenario, it indicates the areas where sediment delivery would be greatest under mainly arable cover, which is likely to increase throughout the catchment in future.

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In this scenario, there is increased risk of sediment delivery in the upper part of the catchment – particularly around LUGG002 and between LUGG005 to LUGG008. In the lower part of the catchment (below Leominster) the increased delivery risk is most pronounced between LUGG017 to LUGG020, around Hope-under-Dinmore and LUGG023.

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Figure 4.5 Sci-Map output for erosion risk under the 2007 CEH land-cover dataset. Image courtesy of the Wye and Usk Foundation

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Figure 4.6 Sci-Map output for an ‘all arable’ land-use scenario, featuring the surveyed reaches as defined within the current study. Image courtesy of the Wye and Usk Foundation

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4.5 Agri-environment Schemes

The Lugg is included in the joint Natural England - Environment Agency Catchment Sensitive Farming Delivery Initiative, which is a nationally funded advice-led partnership which aims to reduce water pollution from agriculture in priority areas.

Additionally, the Lugg has been designated as a candidate pilot catchment under the newly established Water Protection Zone scheme (WPZ) as designated by DEFRA. The zones will provide a regulatory tool to control diffuse pollution to water or physical pressures in high risk areas where existing mechanisms will not meet Water Framework Directive objectives.

In Wales the Glastir agri-environment scheme, which replaces a number of other agri-environment schemes, pays for the delivery of specific environmental goods and services aimed at combating climate change, improving water management and maintaining, enhancing biodiversity and helping meet WFD targets. It is designed to deliver measurable outcomes at both a farm and landscape level in a cost effective way.

The current Rural Development Programme in England has come to an end at the close of 2013. Under the Common Agricultural Policy reforms, a new scheme is due to be launched for the next phase of the Rural Development Programme 2014-2020. The Environment Stewardship scheme is likely to be replaced by the Countryside Stewardship scheme (originally referred to as the New Environmental Land Management Scheme). The English Woodland Grant Scheme is also likely to be merged into this scheme.

4.6 Channel Change and Modifications

4.6.1 Historical Channel Change and Modifications

There is evidence of channel change throughout the Lugg catchment from both anthropogenic and natural means. Historical maps provide an insight into the planform change from the 1800s to 1900s (Old Maps, 2010). In the upper reaches of the Lugg catchment by Llangunllo the river planform has remained stable since the 1800s, with a number of mill leats being introduced around 1889. These mill leats appear to have been removed or cut off from 1977-1980, leaving a single channel.

The River Lugg is most active in the rural areas upstream of Leominster, where it is possible to see evidence of channel migration. The rural areas in between the villages south of Leominster also show evidence of channel migration, but the catchment has also been influenced by the introduction of man-made lakes (around the 1970s), weirs and channel straightening (e.g. 1970-1990 through Leominster).

The development of intensive agriculture from the 1950s in the Lugg catchment has led to a growing threat on the integrity and quality of the Lugg (and surrounding catchment) ecosystems (Internal Drainage Board, 2010).

4.6.2 Past River Management Practices

Records and accounts (held at the British Library) highlight that channel change along the River Wye and Severn catchments, encompassing the River Lugg, were extensive as a result of man-made means. This took the form of channelisation

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works, primarily influenced by the Seven-Trent and Welsh Water Authorities between 1930 and 1980. The major works included embanking, resectioning and concreting. As well as major channel improvements, routine maintenance work was undertaken. This included rubbish removal from urban areas as well as large areas of pioneer tree clearance along continuous lengths of channel. The impact to the flows along these catchments was recorded at several of the gauge stations, with channelisation works being shown to have significant impact.

The major works recorded along the Lugg were primarily focused around Leominster. The works included implementing new embankments or improving current embankments, comprehensive schemes (i.e. channel deepening and widening), resectioning and pioneer tree clearance. These works took place from the 1950s to the 1970s and were controlled by the need for flood alleviation schemes. Major works continued into the 1980s but were becoming increasingly driven by channel improvement schemes (i.e. for navigation) rather than flood concerns.

Summary tables of key works since the 1960s are provided in Table 4.2 (general works) and Table 4.3 (flood schemes) below.

Table 4.2 Timeline summary of works undertaken within the Lugg Catchment between 1960 and 1969

Dates River Description of works 1963,1964,1965,1966, Lugg Stages I, II, III and IV of the Leominster 1967,1968,1969 Flood Alleviation Scheme - Raton Bridge to Crowards. Works included a flood diversion channel, revetments, channel widening and deepening of Lugg and realignment of Ridgemoor brook 1968, 1969 Arrow Eardisland Brook - included dredging to prevent water entering the Southall Brook (part of IDB) 1961,1962,1963,1964 Lugg Hampton Bishop Stank - construction of flood embankments and walls 1960 Pinsley Brook Leominster to Kingsland works – included regrading/ deepening 1960 Eyton Short length of flood embankment at Common Eyton Common (to the south of Brook Leominster town)

Table 4.3 Details of flood schemes undertaken on the Lugg catchment during the 1960s

Date(s) River Lengths affected 1963, 1964 Lugg Mortimer’s Cross to Lyepole 1965, 1966 Lugg Lyepole to Upper Kinsham Bridge 1965, 1966 Lugg Upper Kinsham Bridge to Rossers Bridge 1965, 1966 Lugg Rossers Bridge to Presteigne 1967, 1968 Lugg Rossers Bridge to Presteigne 1968, 1969 Arrow Pembridge Road Bridge to Noke Bridge

Channel maintenance works are still being carried out along the River Lugg by the Environment Agency (Environment Agency Flood Risk Maintenance Programme, www2). These include:

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 Essential bankside vegetation maintenance and structure maintenance (Leominster);  Essential obstruction removal (Upstream of Leominster, Bodenham and north of Hereford) for flood defence purposes; and,  Blockage removal to remove specific Health and Safety hazards to maintain navigation.

4.6.3 Lugg Weir Report

In an Environment Agency (2012) report on priority weirs on the main stem River Lugg, a total of 28 weirs were assessed. The report primarily focused on the ecological constraints of the weirs; however, sediment and fluvial dynamics are also impacted directly affecting the geomorphological quality of the river and the associated river habitats. The presence of weirs poses a significant interruption for the passage of fauna and impedes natural flow diversity that may otherwise be present. Weirs will also impact upon the natural sediment dynamics operating within the fluvial system and may lead to siltation of river gravels.

As part of the assessment, passability scores relative to salmonid, course fish, eels and minor species were assigned. Figure 4.7 illustrates the number of weirs where action was necessary to improve fish passage, such as weir removal or amendments which would ease passage over the individual structures. Of the 28 weirs, 22 were nominated as requiring for further investigation and amendment. Notably, in the river above the Middlemoor weir (Grid Ref: SO325 644) no coarse fish are currently found.

Figure 4.7 Numbers of priority weirs on the main stem Lugg which act as impediments to fish passage. Action required in the form of further assessments, fish passage options or weir removal nominations, are highlighted in red.

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4.7 Hydrology

The Lugg is a river with a freshet hydrological regime in the upper catchment. The flashy hydrological regime is primarily due to the impermeable nature of the bedrock in the upper catchment (Silurian mudstone and shales).

Freshet regimes typically result in sediment transport events during high flows which are of an episodic and seasonally-based nature (Burt, 1996). The discharge response to precipitation is usually fast with overland and throughflow being the main sources of water. The quick response generally subsides soon after the precipitation event, with rapidly decreasing discharge once the source has ceased. Summer flows are generally low, interrupted by episodic higher-flow events due to summer storms and showers. Winter base flow is higher with an increased flood risk (Burt, 1992).

Since the Lugg catchment holds both permeable and impermeable geologies, a range of hydrological responses may occur depending on the degree of porosity or fracturing of the bedrock and the nature of any overlying material. Drift material such as alluvium, soils, glacial till and gravels may potentially act as shallow aquifers regardless of whether the bedrock is impermeable (Burt, 1992).

In Figure 4.8, the seasonality of flow in the Upper Lugg is highlighted. The flashy discharge regime typical of the upland section of the river is evident with some flood peaks reaching up to 60m3 s-1.

Lugg - Daily mean flow (m3 s-1)

70

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40

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01/10/196601/10/196701/10/196801/10/196901/10/197001/10/197101/10/197201/10/197301/10/197401/10/197501/10/197601/10/197701/10/197801/10/197901/10/198001/10/198101/10/198201/10/198301/10/198401/10/198501/10/198601/10/198701/10/198801/10/198901/10/199001/10/199101/10/199201/10/199301/10/199401/10/199501/10/199601/10/199701/10/199801/10/199901/10/200001/10/200101/10/200201/10/200301/10/200401/10/200501/10/2006

Figure 4.8 Discharge (daily mean flow) for the Lugg at Byton gauging station from 1966 - 2006

Data from the Centre for Ecology and Hydrology (CEH) River Flow Archive has been used to compile Table 4.4. This table shows the key hydrological information for the Lugg catchment, including: catchment area, average annual rainfall and mean flows at the two gauging stations along the Lugg.

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Table 4.4 Hydrology information taken from CEH website for the River Lugg Descriptor Byton Leominster Lugwardine National Grid Reference SO364 646 SO502 589 SO548 405 (Butts Bridge) Catchment Altitude Mean 285.7 207.3 158 (mAOD) Catchment Area of Gauge (km²) 203.3 371 885.8 Discharge (mean) (m³ s¯¹) Mean Flow: 3.906 5.877 10.876 95% Exceedance: 0.628 0.957 1.43 10% Exceedance: 8.708 12.7 26.04 Mean Precipitation (1961 – 978 875 812 1990) (mm) Baseflow Index 0.65 0.66 0.62 Factors Affecting Runoff Reduced by Reduced by Natural public water public water supply supply

It may be seen that the mean flow rates increase in the downstream sections of the catchment as the river cross section increases and the number of tributaries meeting the River Lugg increases. The base flow index of 0.62-0.66 shows a connection with the groundwater in the system.

Within the River Lugg catchment (including the Arrow and the Frome) the River Lugg Internal Drainage Board (IDB) is responsible for the water level management and watercourse maintenance of the drainage system. The River Lugg IDB area generally comprises arterial watercourses with more than one riparian owner. Most of the watercourses are subject to regular maintenance, whilst others are on a less regular basis/as required. The catchment is dependent upon a well-maintained drainage system, particularly as it is of rich agricultural land.

4.8 Flood Risk

Flood risk is known to be an issue in 21 communities along the River Lugg catchment, with two key areas of note being Leominster and Eardisland (along the River Arrow). Both of these locations have wide complex floodplain interactions. The Arrow/Lugg confluence has also experienced widespread floodplain inundation. There have been a series of notable flood events within the River Lugg catchment that have been recorded, including in 1947, 1968 and 2007.

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Figure 4.9 Flood risk areas highlighted as blue circles (source: River Lugg IDB)

A Flood Alleviation Scheme (FAS) was constructed along the River Lugg to protect the urban areas of Presteigne and Leominster and to protect agricultural land upstream of Leominster (i.e. the Upper Lugg Improvement Scheme). The FAS was the largest out of these schemes and was thought to have been implemented in the 1970s as part of a major flood defence initiative. The FAS comprises four main components:

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1. A series of earth embankments upstream of Leominster, flanking the river channel. Some of these tie into weirs. Many of these embankments have been damaged by cattle and contain low spots which may lead to flooding. 2. Splitter structures which divert roughly 35% of the flow (100 year flow = 9.1m3s-1) down the bypass channel (River Lugg) and 65% (100 year flow = 16.4m3s-1) down the original channel (Kenwater). 3. Formal earth embankment defences and a wall which defend the left bank of the town in the vicinity of the leisure centre. The defensive line extends from the high ground formed by the tip and extends down the river left bank ending with a wall defence tying in to the main town bridge carrying the A44 Broad Street. 4. The Bypass channel has no formal raised flood defence associated with its operation at present.

Currently, the flood defences in Leominster are being reviewed in light of modelling undertaken in 2013. There are a range of options being considered to improve the standard of flood protection currently in place for the town. The solutions that will be sought are aiming to integrate engineering and environmental requirements and where feasible deliver actions that are supported by both this report and the Management Report that form the River Lugg Restoration Plan. An integrated approach between achieving the Water Framework Directive aims and Flood Risk Management measures may be achieved within this catchment, providing multiple benefits of habitat restoration and flood risk mitigation.

The River Lugg falls within the Wye and Usk Catchment Flood Management Plan (CFMP) which identifies areas at risk of flood with a 1% chance of occurring in any given year. Leominster is identified as one of the key urban areas in the northern extent of the catchment that has the largest number of properties at risk in a 1% AEP flood event.

The River Lugg falls within three sub-areas within the CFMP, these are as follows:

 Upper Wye and Usk – the northern extent of the Lugg upstream of Presteigne.  Lower Wye – the southern extent of the River Lugg downstream of Presteigne.  Hereford – the area surrounding Hereford including the most southern extent of the River Lugg.

Each sub area is assessed and assigned one of six policies. Each policy outlines the type of flood risk applicable to that area and what, if any, commitments, maintenance or management practices will be applied. The preferred policy for the Upper Wye and Usk and the Lower Wye sub areas is Policy 6, whilst the preferred policy for the Hereford is Policy 3. Table 4.5 details the Policy options.

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Table 4.5 Environment Agency CFMP policy options Policy no. Description Policy detail Policy 3 Areas of low to This policy will tend to be applied where the moderate flood risk risks are currently appropriately managed where we are and where the risk of flooding is not generally managing expected to increase significantly in the existing flood risk future. However, we keep our approach effectively. under review, looking for improvements and responding to new challenges or information as they emerge. We may review our approach to managing flood defences and other flood risk management actions, to ensure that we are managing efficiently and taking the best approach to managing flood risk in the longer term. Policy 6 Areas of low to This policy will tend to be applied where moderate flood risk there may be opportunities in some where we will take locations to reduce flood risk locally or more action with others to widely in a catchment by storing water or store water or managing run-off. The policy has been manage run-off in applied to an area (where the potential to locations that provide apply the policy exists), but would only be overall flood risk implemented in specific locations within the reduction or area, after more detailed appraisal and environmental consultation. benefits.

As priorities change there may be opportunities to deliver river restoration measures/actions. For example, if the Environment Agency plans to cease maintaining a flood bank there will be an agreed withdrawal period, to give land owners a chance to consider future options. This may provide an opportunity for a change of approach, helping to deliver the type of measures outlined in this report.

In terms of river restoration, any measures must not increase flood risk to existing built development (residential/commercial/industrial etc.). Detailed Flood Risk Assessments may be required for some restoration proposals to fully assess the impacts and ensure there is no increase in flood risk to sensitive features, e.g. houses, businesses etc. However, increasing the flood risk to farmland/former natural wetland type habitats, e.g. defended floodplain, by actions such as setting back of embankments may be viewed positively if it helps to reduce the flood risk to vulnerable property at the same time as improving river and floodplain geomorphology and biodiversity. Any river restoration measures would require discussion and agreement with the appropriate landowners and could also be supported by agri-environmental schemes or other land management options.

Flood and coastal erosion risk management (FCRM) assets are also present along the length of the River Lugg. At present, there are two schemes being financed within the catchment, Leominster Flood Alleviation Scheme Improvement and the Cherry Brook, Hope-under-Dinmore, Flood Alleviation Scheme both located within the Severn and Wye regional flood and coastal (erosion) committees. These are shown on Figure 4.10. The Environment Agency also oversees maintenance activities along the River Lugg which involves river clearance, structures maintenance and testing and operating assets.

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Figure 4.10a Approximate locations of known flood alleviation schemes and flood defences

Figure 4.10b Approximate locations of known flood alleviation schemes and flood defences

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4.9 Water Resources

4.9.1 Water Abstraction

The river corridor is under pressure from gravel working and water abstraction (Lugg BAP). From data gathered for the River Lugg Conservation Strategy (1996) and the River Lugg Vision (Hyder, 2010), a number of known abstractions are detailed for the River Lugg catchment. There are licensed abstractions in the Teme catchment to supply Pilleth (1.5Ml/d) and Byton (1.1Ml/d). There are also four commercial abstractions at Leominster, as well as 65 spray irrigation licences. In the catchment downstream of Leominster, the abstractions for spray irrigation account for over two- thirds of the abstractions (although this equates to less than 20% of the 95th percentile (Q95) flow).

One of the greatest threats to the volume of water in the river during the summer months is the increased demand for spray irrigation, which had occurred for the 6 years leading up to the River Lugg Conservation Strategy (1996) and have continued past this (Hyder, 2010). This was considered to be a result of the conversion of grassland habitat to arable land use, which included high demand crops such as potatoes.

4.9.2 Flow Regulation

Along the River Lugg catchment there is a series of weirs (approximately 33 in total), some of which are known to have been constructed in an attempt to regulate the flow in downstream sections of the river. Some of these weirs are attributed to the Flood Alleviation Schemes that are detailed in Section 4.8, particularly those upstream of Leominster.

These weirs are likely to have had an impact on the flow and sediment dynamics throughout the catchment by impeding longitudinal connectivity and limiting downstream transfer of sediment. The weir structures and associated bank reinforcement may also create areas of pooling upstream and areas of scour downstream locally altering the river cross-section.

4.9.3 Water Quality

The River Lugg is largely unpolluted throughout its course from source to confluence with the River Wye. The significant influences on the water quality throughout the catchment, including issues with phosphate and sedimentation levels, are as follows (Hyder, 2010):

 Agriculture - fertiliser and pesticide used on arable land, overgrazing of banks etc.) in the middles and lower reaches; and,  Disposal of treated sewage effluents from the small towns and villages along the rivers length.

There are a number of sewage treatment works (STW) within the catchment that discharge to the River Lugg; these are located in the following parts of the catchment (Marsden et al., 1996):

 Kingsland and Bodenham that discharge 200-2,000 Population Equivalents (PE);  Presteigne with discharges of 2,000-7,000 PE; and,

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 Morton-on-Lugg and Leominster with discharges of 9,600 PE.

The sewage works at Leominster contributed 7% of all ortho-phosphate exported from the catchment from statistics taken in 1996 (Marsden et al., 1996). The analysis from the STWs along the River Lugg suggests that there is diffuse pollution (likely to be primarily from agricultural sources) contributing to the levels of ortho- phosphate of up to 90% within the catchment.

All consented discharges into the River Lugg that are greater than 5 cubic metres per day, are monitored on a frequency determined by factors such as volume, variability of performance and risk potential. Through application of the Code of Good Agricultural Practice (COGAP) and implementations of the Control of Pollution (Slurry, Sillage and Agricultural Fuel Oil) Regulations 1991, agricultural pollution is being controlled through inspections of farms within the Lugg catchment.

Further potential issues that have been raised for the River Lugg catchment within the 1996 Conservation Strategy and the restoration vision (Hyder, 2010) are the potential problems of gravel extraction and the increased sedimentation of gravel spawning beds. The gravel extraction practices discharge water into the Lugg via settling lagoons. This previously had no known impact on water quality; however, if further extraction sites are established this may increase the risk of water quality impacts. Sedimentation of the gravel bed of the River Lugg was attributed to conversion of permanent grassland to arable land, which leads to increased sediment loss to watercourse within the catchment.

4.10 Ecology

4.10.1 Fish

Historically, the Lugg has been a rich area for salmon, but counts have fallen drastically over the past 30 years (Burke, 2011). The Lugg, upstream of the town of Leominster, holds brown trout and grayling. Coarse fish are less common above Aymestrey which, until the installation of a fish pass in 2007, also marked the upper limit of Atlantic salmon migration. Spawning salmon have been sighted in more recent years (2009, 2010) on the Arrow at Eardisland and on the Lugg above Lyepole bridge (Pers comm. Marsh-Smith, 2010). Downstream of Leominster, coarse fish including chub Leuciscus cephalus, roach Rutilus rutilus, pike Esox lucius, twaite shad Alosa fallax, eel Anguilla anguilla and barbel Barbus barbus are more common. Stoneloach Noemacheilus barbatulus, minnows Phoxinus phoxinus and bullheads Cottus gobio are present throughout the river.

The Wye Salmon action plan review (DEFRA, 2003) is a document which highlights the key issues for Atlantic salmon on the Wye and its tributaries. The issues were determined by a working group of officers from the Environment Agency, English Nature and representatives from local fisheries groups. The working group established a multi-criteria analysis methodology to identify the main limiting factors to salmon production on the Wye catchment. The main limiting factors identified are as follows (DEFRA, 2003):

 Access to spawning/nursery areas;  Pesticides;  Juvenile survival and recruitment;  Compaction/siltation/loss of spawning gravels;  Acidification;

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 Eutrophication and other diffuse pollution;  Commercial fisheries in the Severn Estuary; and,  Inappropriate management of riparian zone.

The WFD status for water bodies within the lower River Lugg catchment in the 2009 RBMP indicated that fish populations were failing to meet good ecological status in the most downstream water body (GB109055036790 – Confluence of River Arrow to confluence of River Wye), where the fish status was poor. In the latest interim update of the RBMP classifications, an improvement in the fish status is indicated. Good ecological status is met more broadly in the upper reaches of the Lugg (above the Arrow confluence) but with no clear status for fisheries within the English section in the 2009 RBMP (highlighted as moderate in the Welsh section of the water body – Cascob Brook to confluence Norton Brook). Recent interim classifications suggest an improvement in the fish status within the English section of the water body (GB109055042030). Reasons for failure to meet good status for in the head of the Lugg catchment may be obstructions to migration, variable water quality or physical habitat modification.

4.10.2 Invertebrates

The River Lugg has not been subject to extensive invertebrate surveys. Several species of national status have been found in the River Lugg and were identified within the River Lugg Conservation Strategy (1996). These included the pea mussel (Pisidium tenuilineatum) and aquatic beetle/alder fly (Riolus cupreus and R. subviolaceus/Salis nigripes). These finds indicated that the Lugg could hold significant communities of invertebrates.

Information provided within the River Lugg Vision (Hyder, 2010) also identified a variety of rare and scarce invertebrates from the Lower Lugg, supporting information provided in the conservation strategy. The species included the nationally rare pea mussel (Pisidium tenuilineatum); a species that requires unpolluted conditions.

Within the RBMP Annex C, measures to improve the detection of pollution incidents and to have more frequent monitoring of river macroinvertebrates is detailed in an attempt to address pressures from harmful substances such as organic pollutants and priority hazardous substances.

4.10.3 Birds

The River Lugg provides good habitat for a range of typical river birds. Dipper Cinclus cinclus is found on the upper reaches, with kingfisher Alcedo atthis occurring more on the middle and lower stretches. Grey wagtail Motacilla cinerea occur throughout. Several pairs of mute swan Cygnus olor and common sandpiper Actitis hypoleucos also breed on the river, as do mallards Anas platyrhynchos which are plentiful. Some active cutting faces of the meanders hold colonies of sand martins Riparia riparia.

4.10.4 Alien Invasive Species

Several non-native invasive species are present within the River Lugg catchment in certain areas. The North American signal crayfish Pacifastacus leniusculus has been detected in the river, particularly in the Dinmore ditch near Hope-under- Dinmore in the Lower catchment. Signal crayfish may limit fish recruitment as they predate on fish eggs and compete with the native white-clawed crayfish

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Austropotamobius pallipes through predation of the macro-invertebrate food resource. They may also carry a fungal infection (Aphanomyces astaci) – commonly known as the crayfish ‘plague’ which may decimate local native crayfish populations if infected.

In terms of incidences of non-native invasive plant species, Himalayan balsam Impatiens glandulifera was recorded within the Lugg river basin district (EA, 2009) and New Zealand Pigmyweed Crassula helmsii has been recorded on the Dinmore ditch in the Lower Lugg catchment. The River Wye catchment (including the River Lugg) is under a considerable threat from the following three invasive weed species: giant hogweed (Heracleum mantegazzianum), Japanese knotweed (Fallopia japonica) and Himalayan balsam (Impatiens glandulifera). These species may lead to the loss of natural catchment biodiversity by smothering native species. As well as this, these invasive plants (and annuals such as nettles) typically die off in the winter months, which may potentially lead to a reduction in bank stability, leading to increased erosion. Himalayan balsam and nettles also have shallow rooting thus providing minimal soil binding increasing the erosion risk to the river banks and soils even during the growing season. The invasive non-native species control programme is one of the remedies for improving the condition of the SSSI units.

The Herefordshire LBAP (Local Biodiversity Action Plan) sets out 14 targets for this habitat, all of which are directed towards the achievement of the WFD objectives. Stakeholder participation, particularly from landowners, is vital to work towards implementation of the LBAP targets. T10 (target #10) is the control of alien invasive species.

Some local initiatives are already in place within the Wye catchment looking to begin to work on the presence of invasive species. One such project is the ‘Giving up the weed’ initiative which is run by the Wye and Usk Foundation and works on weed control in the whole of the Wye catchment (both in England and Wales). This initiative particularly focuses on giant hogweed, Japanese knotweed and Himalayan balsam.

4.10.5 Phytophthora

Plant and tree diseases are present within the catchment, in particular Phytophthora. Phytophthora is derived from Greek and means ‘plant destroyer’. They are a large group of pathogens that cause diseases in plants and tree species. There are many different forms which may affect different plant and tree species. Phytophthora typically causes the die back of the plants and trees. Along the River Lugg the spread of this disease could lead to the die back of bank side vegetation leaving the bank unstable and without a riparian buffer strip. Alders are particularly susceptible to phytophthora and whilst this disease is not as widespread within the Lugg catchment as in other catchments, concerted effort to control the spread of this disease now could deliver significant benefit.

4.11 RHS Habitat Modification Score Analysis

Watercourses with a high degree of naturalness are governed by dynamic processes which result in a mosaic of characteristic physical biotopes, including a range of substrate types, variations in flow, channel width and depth, in-channel and side-channel sedimentation features (including transiently exposed sediments), bank profiles (including shallow and steep slopes), erosion features (such as cliffs) and both in-channel and bankside (woody and herbaceous) vegetation cover. All of

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these biotopes, and their characteristic patterns within the river corridor, are important to the full expression of the biological community. A range of physical habitat modifications cause simplification of biotope mosaics, resulting in declines of characteristic biota dependent upon biotopes that have been lost or reduced in extent. An indication of the extent and severity of physical habitat modification may be gained by looking at River Habitat Survey (RHS) data.

A total of 21 River Habitat Surveys (RHS) were carried out by the Environment Agency between 1994 and 2007 covering all SSSI units of the River Lugg (England). The majority of the surveys are located in Unit 1, in the downstream extent of the Lugg. Locations of the mid points of these surveys (which are 500m in total length) are indicated on Figure 4.11 and are colour coded according to the Habitat Modification Score (HMS) classes.

According to the RHS carried out between 1994 and 2007 on the River Lugg, three sections of the river were classed as being ‘severely modified’ reaches (HMS Class 5). These three reaches were recorded to have undergone extensive resectioning with some bank reinforcement also recorded. This resectioning is likely to be a result of historic channelisation activities that were carried out to improve the capacity of the channel to convey flows. Two of these ‘severely modified’ reaches are located in the area surrounding Leominster (SSSI Unit 2 and 3), whilst the other is located upstream of Marden (SSSI Unit 1).

One section of the river was classed as being ‘significantly modified’ (HMS Class 4), which was recorded to have a major ford crossing the channel in the survey reach, which will have had a considerable physical modification to the channel. There was no channel resectioning or bank protection recorded. This reach is located upstream of Hereford in SSSI Unit 1.

Sections of the river classed as ‘obviously modified’ (HMS Class 3) are widespread throughout the Lower Lugg, with four reaches identified from Presteigne to Hereford. The sites scored as HMS Class 3 typically had a combination of some of the following physical modifications: resectioning/reprofiling, bank reinforcements and/or the presence of a bridge.

The RHS data analysis (Figure 4.12) shows that 43% of the surveyed reaches are characterised as ‘predominantly unmodified’ (HMS Class 2) and 14% are characterised as ‘pristine/near natural’ conditions (HMS Class 1). Those classified as HMS Class 2, are generally considered to not be in ‘pristine/near natural’ conditions as a result of relatively small areas of poaching, small sections of bank toe reinforcement and bridge structures.

The remaining 43% of RHS sites fall into HMS class 3-5 of which 24% are obviously modified (HMS class 3), 5% significantly modified (HMS class 4) and 14% severely modified (HMS class 5). This suggests that almost half of the River Lugg is modified and therefore requires restoration.

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Figure 4.11 Map of RHS survey mid points and RHS Habitat Modification Score classes

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Figure 4.12 HMS class from RHS carried out between 1994 and 2007 on the Lower Lugg showing the percentage of RHS sites in each class

4.12 Wider Environment

Beyond the confines of the river planform a number of other receptors should be considered in the development of restoration visions and any subsequent actions. It is important to consider how restoration of the River Lugg would affect the wider environment, particularly other protected areas and designated sites.

4.12.1 Designated Sites

The River Lugg abuts a number of SSSIs and is within the Impact Risk Zones (IRZ) for these SSSIs. The IRZ is a tool used by Natural England to show the zone of sensitivity for each SSSI in which notification and specification of the types of works/development is required to assess the potential for adverse impacts. The SSSIs are detailed in Table 4.6 providing a brief summary of their current condition, with Figure 4.13 providing a location plan for each of the receptors.

The lower section of the River Lugg from Hope-under-Didmore is also part of the River Wye SAC.

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Table 4.6 Information on SSSIs that abut the River Lugg (Natural England, 2014) SSSI name Unit Condition Area Reason for adverse condition status status (if applicable) Byton & 1 Unfavourable 4.71 Overgrazing, inappropriate water Combe - recovering levels Moors 2 Unfavourable 1.25 Inappropriate cutting/mowing, – no change overgrazing, drainage 3 Unfavourable 9.35 Overgrazing, undergrazing, – no change inappropriate water levels, lack of corrective works (inappropriate ditch management) 4 Unfavourable 2.92 Overgrazing, undergrazing, – no change inappropriate water levels, lack of corrective works (inappropriate ditch management) Rockhall 1 Favourable 1.66 - Quarry Dinmore Hill 4 Unfavourable 99.25 Forestry – deer grazing/browsing Woods - recovering 6 Favourable 25.78 -

Lugg and 1 Favourable 61.91 - Hampton Meadows 2 Favourable 71.07 -

3 Favourable 22.7 -

There are also a number of other designated sites within the vicinity of the River Lugg, including Local Nature Reserves (Queenswood and Broadlands), an Area of Outstanding Natural Beauty (AONB) and National Trust areas (e.g. Pokehouse Wood).

Restoration of the River Lugg could have potential impacts on these adjacent receptors. Restoration aimed to naturalise and improve the River Lugg is most likely to have a positive impact on the surrounding designated sites particular those used for recreational purposes. However, it should be noted that in altering the existing processes and dynamics within the channel could lead to subsequent impacts on existing processes outside the channel in adjacent sites. This would be of particular importance for the Lugg and Hampton Meadows SSSI, which is directly reliant on the winter season flooding to provide annual enrichment to create productive soils, aiding to grow a nutritious, high volume hay crop.

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Figure 4.13a Key designated sites within the vicinity of the Lower Lugg

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Figure 4.13b Key designated sites within the vicinity of the Lower Lugg

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4.12.2 Biodiversity Action Plan (BAP) Habitat

UK Biodiversity Action Plans (for habitat and species) were succeeded by the UK Post 2010 Biodiversity Framework (2012). In England the most recent biodiversity strategy is ‘Biodiversity 2020: A strategy for England’s wildlife and ecosystem services’ and provides a comprehensive picture of how biodiversity commitments are being implementing at international and EU levels.

The River Lugg is part of the Herefordshire Local Biodiversity Action Plan. Important habitat features within the River Lugg include those of migratory fish (particularly Atlantic salmon), otter and native freshwater crayfish. The River Lugg and Wye are detailed as priority catchments as part of the Herefordshire Local Biodiversity Action Plan. The Lugg Internal Drainage Board has also developed a sub-plan for the arterial drainage systems, providing a holistic approach within the catchment (Internal Drainage Board, 2010).

A series of actions are provided within the BAP which could benefit from restoration strategies within the River Lugg catchment. These include the following:

 Promotion of maintenance, restoration and creation of key habitats within the Lugg catchment (e.g. hedgerows, grassland, watercourses, wetlands and ponds);  Improving connectivity between habitats, especially along river corridors;  Summer and winter feeding and nesting habitats;  Encouraging best practices in areas such as: soil management, pesticide use, managing river and stream land (i.e. buffer strips);  Water abstraction;  Control and eradication of invasive species; and,  Water and energy efficiency, linking to the long term sustainability and resilience of agriculture.

4.12.3 Historic Environment

The Wye Valley (including the River Lugg) flows through an area with rich historical environment which, despite evidence of prehistoric settlements, field systems, Roman sites, medieval castles and more recent industrialisation, occupation has remained at a sufficiently low level as to not significantly impact upon the river environment (Natural England, 2012).

The Lugg valley has been an important focus for human activity for millennia, with local life anticipated to be closely tied to the River Lugg. A result of this activity is the familiar network of old buildings, quarries, lanes, fields and villages that have resulted from hundreds of years of local community life. The remains of ‘ridge and furrow’ fields suggest that the area has long been used for agricultural processes, with the river floodplain currently still seen to be a ‘patchwork’ of fields. Gravel quarrying is particularly evident within the low hills that border the river floodplain in the lower valley of the Lugg.

A review of information from the Heritage Gateway (2014) and the Multi-Agency Geographic Information for the Countryside (MAGIC) (Defra, 2014) has identified several scheduled monuments, listed buildings and registered park and gardens within the vicinity of the River Lugg and its floodplain. Table 4.7 provide details of the sites within the River Lugg corridor with Figure 4.14 providing a location plan of

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all assets within 5km. There are a number of bridges spanning the river that are listed buildings or scheduled monuments, as well as weirs and mills adjacent to the river. These assets would need to be considered in any restoration strategy implemented but are unlikely to pose a significant constraint to any catchment scale river restoration measures. Care will need to be taken for any works within the vicinity of these archaeological constraints, with detailed mitigation measures likely to be required.

Table 4.7 Information on key listed buildings, scheduled monuments and registered parks and gardens in the River Lugg catchment Name Type Grid Reference Reach Location Lugg Bridge Scheduled SO 31651 64615 LUGG001 monument Lugg Bridge Listed building SO 31652 64617 LUGG001 Stapleton Lodge Listed building SO 31656 64644 LUGG001 Bowl barrow 460m south of Scheduled SO 36061 63965 LUGG002 Lower Court monument Lower Court Listed building SO 36089 64424 LUGG003 Church of All Saints Listed building SO 36434 64910 LUGG003 Kinsham Court Listed building SO 36453 64955 LUGG003 Shirley Farmhouse Listed building SO 38394 65284 LUGG004 Castle mound in Camp Wood Scheduled SO 39594 65394 LUGG005 monument Aymestrey Mill Listed building SO 42441 65580 LUGG006 Barn about 5 metres north of Listed building SO 42500 65427 LUGG006 the Crown Inn Water mills and quarry at Scheduled SO 42593 63984 LUGG008 Mortimer’s Cross monuments Lugg Bridge Listed building SO 42661 63685 LUGG008 Lugg Mill Listed building SO 44719 62278 LUGG008 43, 45 Broad Street Listed building SO 49577 49335 LUGG013 3, 5, 7 Bridge Street Kenwater House Former Assembly Room at rear of No.45 Leominster Priory Scheduled SO 49886 59332 LUGG013 monuments Footbridge over River Lugg Listed building SO 49776 59382 LUGG013 associated guard rails 6-12, 15, 17 The Priory Bridge over River Lugg at SO Listed building SO 50790 58500 LUGG014 5073 5850 North West Bridge over River Lugg and Listed building SO 50810 57967 LUGG015 Leat Head 150 metres west of Eaton Hall Eaton Hall and two associated Listed building SO 50880 58042 LUGG015 barns Wharton Court Listed building SO 51118 55862 LUGG015

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Name Type Grid Reference Reach Location Ford Farmhouse and adjoining Listed building SO 51122 55277 LUGG015 granary Hampton Court Bridge Listed building SO 51444 52849 LUGG017 Hampton Court Registered 31ha LUGG018 park and garden The weir house and flanking Listed building SO 53550 51170 LUGG019 walls Bodenham Bridge Listed building SO 53501 51119 LUGG020 Leystone Bridge Listed building SO 51806 47676 LUGG022 Church of St Mary Listed building SO 51180 47057 LUGG022 Lugg Bridge Scheduled SO 53192 41810 LUGG025 monuments; listed building Bridge over River Lugg at Listed building SO 55852 38878 LUGG026 SO559389 Lock on River Lugg toward Listed building SO 56898 37503 LUGG026 confluence with Wye Floods arches and causeway Listed building SO 56944 37485 LUGG026 walls to Mordiford Bridge

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Table 4.14a Locations plan of key listed buildings, scheduled monuments and registered parks and gardens in the River Lugg catchment

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Table 4.14b Locations plan of key listed buildings, scheduled monuments and registered parks and gardens in the River Lugg catchment

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4.12.4 Landscape

Despite the localised industrialisation of the nearby Lower Wye valley since Iron Age times, there are limited obvious clues of industrialisation within the current environment, which has maintained its largely natural landscape. The landscape has been subjected to increasingly intensified agricultural practices, which were initially pasture/grazing, but in recent years is beginning to shift to more arable nature.

There are many distinctive semi-natural habitats some of which are of international and national importance including ancient woodland and replanted ancient woodland, traditional orchard, lowland meadows and fens.

Within England, natural land boundaries have been defined. National Character Areas (NCAs) divide the country into 159 distinct natural areas. These are based on a combination of landscape, biodiversity, geodiversity and economic activity. They follow natural lines in the landscape rather than administrative boundaries. Natural England are currently revising its NCA profiles, as part of its responsibilities in delivering the Natural Environment White Paper, Biodiversity 2020 and the European Landscape Convention, in order to make environmental evidence and information easily available to a wider audience. Revised profiles for all 159 Character Areas are due to be published by April 20149 . These documents provide a wealth of information, including land classification and detailed ecosystem service analysis of each of the NCAs.

The Lower Lugg is located in two NCAs. The reaches from the border with Wales in Presteigne to Mortimer’s Cross lie within 98 Clun and North West Herefordshire Hills, with the rest of the reaches located within 100 Herefordshire Lowlands. The following provides a summary of the Clun and North West Herefordshire Hills NCA and Herefordshire Lowlands NCA (Source: Natural England, 2013).

Clun & North West Herefordshire Hills NCA

The Clun and North West Herefordshire Hills NCA is largely tranquil, undulating rural area that is sparsely populated. It is divided by the river valleys of the Clun and Teme. The landscape slopes down to the Herefordshire Lowlands NCA from the higher, wind-swept heath and grasslands. The hill tops typically consist of plantation and native woodland.

The Downton Gorge National Nature Reserve is one of the most ecologically important areas of these valleys and is also designated as a Special Area of Conservation (SAC). In the centre of the NCA are the steep-sided, shallow-domed hills of the Clun Forest. There are long views down narrow, twisting valleys which widen towards the east of the NCA. The Shropshire Hills Area of Outstanding Natural Beauty (AONB) covers a significant proportion of the northern part of the NCA. This NCA is of particular importance for its fast-flowing rivers, including the Teme, Clun and Lugg. The River Lugg is designated as a SSSI for its important flora and invertebrate fauna, notably the populations of white-clawed freshwater crayfish and otter. The area holds a large number of historic environment interests, including the 8th century Offa’s Dyke.

9 http://www.naturalengland.org.uk/publications/nca/

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The area has a cool climate with high rainfall and acidic brown earth soils. This typically gives rise to moorland vegetation in the uplands, whilst arable cultivation occurs on the lower slopes where the soils are silty but drain freely.

Statements of Environmental Opportunity (SEOs) are suggested for each of the NCAs. These offer guidance on critical issues that could help to achieve sustainable growth and a more secure environmental future. There are four SEOs identified for the Clun and North West Herefordshire Hills NCA. These cover the protection, management and enhancement of the open, expansive upland habitats of the Clun (SEO1), the protection, management and enhancement of the valley habitats (SEO2), the protection and management of the rivers Teme, Clun and Lugg and associated watercourses (SEO3) and the conservation and enhancement of the area’s distinctive historic environment (SEO4). The most relevant one to this project is SEO3. One focus of this SEO is to protect and manage the rivers floodplains, wetlands and woodlands, with the aim of maintaining high water quality and enhance their nature conservation interest. SEO3 also looks at helping to reduce the potential risk of flooding both within the NCA and downstream, as well as increasing the recreational opportunities they provide.

Herefordshire Lowlands NCA

The Herefordshire Lowlands NCA lies almost entirely within Herefordshire, with small areas to the north and east in Shropshire and Worcestershire and to the south-east in Gloucestershire. It is largely tranquil and rural in character but does include the larger settlements of Hereford and Leominster. There are small dispersed settlements of hamlets and villages, many of which contain older buildings with the local vernacular of black-and white timber-framed buildings. Restored cider barns with characteristic double doors and historic farmsteads are also common.

The landscape is gently undulating with steep-sided cornstone hills in the central area dominated by ancient woodland of ash and field maple or oak and bracken. Woodland within the area is a significant landscape feature, typically on the hill tops and valley sides. Many of these woodlands are actively managed (commercially) to produce quality timber, for example Garnons Estate. The NCA is an important area for commercial agricultural supported by the fertile and high-grade agricultural soils; the farming is mixed arable and livestock. Traditional orchards are still to be found, though suffering decline, with new orchards and dwarf varieties of trees also common. The area is also important for commercial production of soft fruit under polytunnels, supplying much of the UK. Historic parklands such as at Berrington Hall have many veteran trees that are important for invertebrates.

The wide, meandering river valleys of the Wye, Lugg and Frome create a distinctive lowland area amongst the gently undulating landscape with localised steep sided hills of Herefordshire Lowlands NCA. Much of the area is underlain by Old Red Sandstone, with localised deposits of alluvium and glacial drift. The rivers and their floodplains are recognised as major ecological, agricultural and recreational assets. Fertile soils support intensive mixed agriculture and pasture land with occasional wet meadow and permanent grassland is found along the river corridor. The whole NCA, including the river valleys, are recognised as tranquil areas and relatively undisturbed by major infrastructure aside form a few A roads between Hereford, Hay-on-Wye and Leominster.

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Statements of Environmental Opportunity (SEOs) are suggested for each of the NCAs. These offer guidance on critical issues that could help to achieve sustainable growth and a more secure environmental future. There are three SEOs identified for Herefordshire Lowlands NCA. These cover the protection and management of the River Wye SAC and the other watercourses and floodplains (SEO1), the protection and enhancement of the natural and historic environment (SEO2) and the protection, management and restoration of semi-natural habitats within the rural and urban areas of the NCA (SEO3). The most relevant one to this project is SEO1. One focus of this SEO is the development of riverine environment to tolerate more extreme flow levels by protecting and creating new wet meadow and woodland in the floodplain. Another is on the recreational opportunities related to the riverine environment. SEO3 picks up on the need to improve ecological connectivity, biodiversity, flood water storage capacity and ability of the landscape to adapt to the impacts of climate change.

4.12.5 Amenity, Recreation and Navigation

From Rosser’s Bridge near to Presteigne to the confluence with the River Wye the River Lugg is a public navigation. There are a number of weirs along the River Lugg which along with the channel size limit the possibility of navigation by larger boats. Some canoeing takes place on the river, with the most popular get-ins located at Lugg Green and Mortimer’s Cross; canoeists also occasionally launch from Aymestrey Bridge when river levels are suitable. An improvement to portaging signage and access around weir structures has occurred over the past decade.

From August to October 2003 Environment Agency staff were also commissioned to conduct a study of the entire river assessing the barriers to navigation. A number of fences spanning the river, weirs, bridges and debris dams were identified and action recommended for the removal of fencing from across the channel.

Public access to the riverbank of the Lugg is very limited, with only a few sections accessible by a public right of way. As a result, recreational activities are minimal, with fishing likely to be the major activity within the catchment.

River restoration may provide the potential for creating a greater recreational value or amenity use of a river by opening up the river corridor, creating natural features or removing man-made structures. Restoration measures should seek to fully assess potential impacts on recreational users.

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5 Contemporary River Characteristics

5.1 Geomorphological Characteristics

5.1.1 Channel Planform

The Lower Lugg is typical of a UK lowland river with a low gradient, and a meandering planform. The river upstream of Leominster exhibits an actively meandering planform, which progressively shifts to a passively meandering channel planform downstream of Leominster (Figure 5.1a). The River Lugg has a straighter planform (with some evidence of resectioning) in the vicinity of the urban areas, especially Leominster and Presteigne (Figure 5.1b).

(a) (b)

Figure 5.1 Examples of the River Lugg planform during the site survey: (a) actively meandering and (b) straight planform

The channel width varied between 5m in the upper surveyed section near Presteigne to 15-25m in the lower surveyed section near the River Wye confluence. The river banks ranged from being gentle slopes to vertical banks, ranging in height from approximately 0.3m to 3m. Where the banks of the Lugg were exposed material comprised clay, silt and earth. There were some banks with fine and coarse gravel present, a likely reflection of the superficial alluvium geology of the area.

5.1.2 Floodplain Connectivity

The upper section of the Lower Lugg from Presteigne downstream flows through a wide, unconfined floodplain until it reaches Lower Kinsham, where the valley becomes enclosed and the river assumes a confined meandering planform with limited floodplain until Aymestrey. After this, the valley opens out again and continues to flow through an unconfined floodplain that becomes wider as the river reaches its confluence with the River Wye. In the lower surveyed sections of the Lower Lugg, the banks are typically vertical and approximately 2-3m high. This is not typically characteristic of natural lower catchment channels where the banks would usually be lower and the channel would be wider. This could be due to historic dredging and/or channel clearance, typically found in agricultural areas to increase channel capacity and conveyance and lower potential flood risk. This acts to disconnect the channel from its floodplain, particularly in low flow conditions. The

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Lugg is embanked on both banks for the majority of its length from Sutton St Nicholas to the River Wye confluence again reducing some lateral floodplain connectivity, although the embankments are typically set back by a minimum of 8m (Figure 5.2). Figure 4.10a and Figure 4.10b provide an overview of the location of the known flood defences (including embankments), including those observed during the fieldwork.

(a) (b)

Figure 5.2 Examples of the River Lugg embankments in the lower surveyed reaches: (a) embankment close to the river edge and (b) set back embankment on the right bank

5.1.3 Flow Variation

At the time of the surveys the predominant flow type along most of the bespoke fluvial audits/spot checks was a combination of both glide flow and run flow (Figure 5.3a). Riffles were present in places along the Lower Lugg marking shallower areas of water, a step change in gradient and coarse gravel/cobble deposition within the channel. During the survey, broken and unbroken standing waves were also observed, particularly around in-channel structures such as weirs and bridges but also over some riffle features (Figure 5.3b). The RHS data (1995-2007) noted the predominant flow type to be glide flow.

(a) (b) Figure 5.3 Typical flow on the Lower Lugg: (a) glide/run flow and (b) an example of broken standing waves

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5.1.4 Bed Substrate

The surveys conducted in January/February were after a period of very high rainfall when the River Lugg levels were high and the bed of the river obscured; in comparison, the survey undertaken in October was in low flow conditions.

Where the channel bed was visible the predominant bed substrate consisted of coarse gravels, pebbles and some cobbles (Figure 5.4a). There was a lot of fine sediment present in the water column in the January/February surveys as a result of the high flows, which is likely to have settled out on the river bed as the flow subsided. Some fine sediment was evident during the October surveys particularly in the slower flowing areas and margins (Figure 5.4b).

The RHS data (1994-2007) shows that silt was recorded at the majority of the surveyed locations and that each site had gravel/pebbles present. This is what is expected of the SSSI river types present on the Lower Lugg (River Types I, II and VI) based on Mainstone (2007). Under low anthropogenic impacts, the bed of the Lower Lugg is likely to be dominated by silts and sands, with cobble accumulations at riffles (Types I and II) and gravels and cobbles (Type VI) under low anthropogenic impact.

(a) (b) Figure 5.4 (a) Typical substrate in the Lower Lugg; (b) Silt evident at the channel margins in some locations

5.1.5 Erosion

The River Lugg is a naturally active channel and was observed to be laterally migrating and actively eroding its banks in a number of reaches, including LUGG001-006, LUGG008-009, LUGG015 and LUGG022-026. The banks are vertical and steep in a number of these reaches, being approximately 3m high in places (Figure 5.5a).

In locations, the banks are being undercut by the river, with evidence of mass failure of the bank in the form of slumping (Figure 5.5c). It must be noted that this illustration is likely to show accelerated erosion rather than natural erosion processes. Poaching of the banks by cattle and sheep has also accelerates erosion occurring in some locations, contributing fine sediment into the river channel (Figure 5.5b).

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(a) (b)

(c) Figure 5.5 (a) Vertical banks approximately 3-3.5m high; (b) Poaching of the channel banks to the river edge; (c) undercutting of the channel bank and associated bank collapse

5.1.6 Deposition

During the October survey, the lower flow conditions meant that depositional features in the channel were evident. Throughout the bespoke fluvial audits and spot checks a number of depositional features were noted, including riffles (Figure 5.6a), side bars (Figure 5.6b), point bars, mid-channel bars (Figure 5.6c) and berms (Figure 5.6d). Reaches including LUGG001-006, LUGG008-009 and LUGG022-026 were particularly active, with depositional features consisting of fine/coarse gravels, cobbles and pebbles.

Most of the depositional features were not vegetated suggesting that they are likely to be temporary features that migrate within the channel in differing flow conditions.

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(a) (b)

(c) (d) Figure 5.6 (a) Riffle depositional feature; (b) Side bar depositional feature; (c) Mid-channel bar depositional feature; (d) Berm feature as a result of bank slumping

5.2 Land Use and Vegetation

The majority of the banks along the Lower Lugg were vegetated with grass, reeds and broadleaf trees. The extent of riparian zone varied along the River Lugg. The majority of the sites surveyed upstream of Eyton had a semi-continuous to continuous riparian zone; whilst the riparian zone in the areas downstream of this were primarily absent or intermittent. The tree lining was predominantly scattered, with some sections of continuous trees particularly related to wooded areas adjacent to the channel.

The land use surrounding the river was predominantly agricultural, ranging from semi-improved grassland, pasture and arable tilled land. There were many areas with no buffer strip between the agricultural land use and the river, with only very few areas having a suitable buffer strip (Figure 5.7a). In some areas the riparian zone is extensive, particularly from Lower Kinsham to Aymestrey as the river passes through a steeper section with a limited floodplain. Some areas also had a wet woodland habitat forming alongside the river with a set-back embankment cutting the river off from the agricultural land use (Figure 5.7b).

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(A) (b) Figure 5.7 (a) Lack of a riparian buffer strip along the River Lugg and (b) a setback embankment (in blue) with the river following the tree lining

5.3 Channel Modifications

5.3.1 Weirs

There were a number of weirs recorded along the river notably in LUGG008-014 upstream of Leominster. A number of these were structures associated with the flood alleviation schemes that have been put in place to slow the water as it approaches the urban areas along the river. Figure 5.8 provides a location plan of the weirs noted throughout the surveyed Lower Lugg. Using aerial imagery it is also possible to see a number of small weirs that are associated to mills and local estates.

The weirs had bank and bed reinforcement associated with them both upstream and downstream of the structures. In some locations the bank reinforcement was being undermined at both the upstream and downstream extents with the river, adjusting/widening as a result of the weir structure. Poaching of the bank also enhanced this in some locations. The weirs typically resulted in areas of erosion downstream, where the river had created large scour pools, which in some cases were over 25m wide (Figure 5.9). Areas of ponded flow upstream of the weirs were observed, particularly on the major structures, providing an area of sedimentation that was deep with smooth flow.

The presence of weirs within a river system are recognised to lead to changes in the natural longitudinal sediment and flow dynamics both locally and on a reach to catchment scale. The areas of erosion observed, particularly in the downstream scour pools, provide an accelerated input of fine sediment from the earth banks to the downstream catchment. This could lead to an impact on downstream geomorphological and ecological habitats. The weir structure itself also acts as a barrier to sediment movement within system, particularly during low flow conditions. This may starve sections of sediment and alter the natural sediment dynamics. Weirs also act as a barrier to movement of species within the catchment including fish, crayfish and plant communities. Flow dynamics are likely to be altered locally, creating areas of unbroken/broken standing waves which may cause enhanced erosion within the area. The areas of slacker flow upstream and downstream may subsequently cause sedimentation.

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Figure 5.8a Location of weirs observed during fieldwork and from Ordnance Survey maps

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Figure 5.8b Location of weirs observed during fieldwork and from Ordnance Survey maps

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Weir

Figure 5.9 Scour pool created by one of the weirs surveyed in the upstream reaches of the River Lugg above Leominster The Environment Agency (2012) report on priority weirs on the main stem River Lugg, summarised in Section 4.6.2, highlighted that 22 out of the 28 weirs studied required further action to be taken. This included further investigation and amendments to enable fish passage as well as reinstating sediment and flow dynamics that have been subsequently impacted by the structures.

5.3.2 Embankments

Embankments were noted along the bespoke fluvial audit from Eyton to Leominster (LUGG010-012) and from Lugwardine to Mordiford (LUGG024-026). These were typically set back from the river’s edge, providing a small buffer strip of grass and tree lining (Figure 5.2b). The RHS survey data also shows one location with embankments by Lugwardine. The embankments in the lower surveyed section downstream of Lugwardine were approximately 5-8m wide and 2m high.

5.3.3 Bridges

There were a number of major bridges crossing the River Lugg, primarily allowing road access across the river. Some minor bridges were recorded during the surveys allowing local access across the river to agricultural land on either side of the river. These structures were primarily constructed from brick and appeared to historical. In the lower surveyed sections footpaths follow the Lugg for large sections, with small footbridges providing access.

5.3.4 Channel Straightening and Widening

The Lower Lugg appeared to have been historically widened and straightened in several reaches throughout its catchment, particularly through the urban areas such as Leominster (Figure 5.11). These sections are likely to have been modified for navigational purposes and as part of historic flood alleviation schemes. Figure 5.10 highlights the sections of the Lower Lugg that were observed during the bespoke fluvial audits and spot checks to have shown evidence of historic straightening. These sections of river typically act as a transfer of flow and sediment and were recorded to have few depositional features and flow variety. The sections of the Lower Lugg that were observed to be widened typically had sufficient flow observed during the time of surveys. However, in low flow periods, there could be the potential for the channel to be over-wide with associated negative impacts on in- channel habitats and subsequent ecological receptors.

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Figure 5.10a Cross-section modifications, channel straightening and widening observed whilst on site

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Figure 5.10b Cross-section modifications, channel straightening and widening observed whilst on site

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(a) (b) Figure 5.11 a) Historically modified section of the River Lugg in reach LUGG003 b) Straightened section of the River at LUGG012

5.3.5 Bank Reinforcement

Bank reinforcement was observed within a number of the surveyed reaches of the Lower Lugg, particularly where the river lies within the proximity of infrastructure such as roads, bridges and buildings, as well as where weirs are located (Figure 12a – LUGG016). Concrete banks locally remove sections of riparian corridors and marginal habitat. Bank reinforcement may also limit flow variation and availability of habitat for aquatic fauna. In removing a section of natural bank a source of sediment is removed which may lead to changes in the local erosion and deposition dynamics.

Soft engineering techniques, such as willow spilling, were also observed on site, namely within the upper section of the catchment. Figure 12b provides an example of one of these sections in LUGG009, although enhanced erosion was observed downstream of the structure.

(a) (b)

Figure 5.12 a) Concrete bank reinforcement introduced to the River Lugg at LUGG016 b) Willow spilling added in an attempt to protect bank from erosion in the upper section of the catchment at reach LUGG009

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5.4 Point and Diffuse Sediment Sources

Throughout the bespoke fluvial audits and spot checks a series of point and diffuse sediment sources were noted adjacent to the River Lugg, these are shown in Figure 14. Point sediment sources consisted of outfalls draining into the channel (Figure 5.13a), poaching (Figure 5.13b) tributaries and field drains. Poaching was extensive in a number of the surveyed sections of the Lower Lugg, particularly LUGG002, LUGG008-012 and LUGG026. Diffuse sediment sources were typically from tilled agricultural land adjacent to the river with little to no riparian zone providing a buffer for the river channel (Figure 5.13c). A number of fields had furrows perpendicular to the river, meaning any runoff from rainfall events was directed towards the channel. The predominant land use in the catchment was observed to be arable farming and tilling of soils which, from historical map analysis, has been the case for centuries with the catchment being permanently pasture. In some parts of the catchment there has been a growth in intensive horticulture and polytunnel farming which also may impact natural soil infiltration and accelerate runoff from the sites.

Road drainage may also act as a point sediment source, capturing fine sediment runoff from the surrounding agricultural land and transmitting this to the river system in a relatively efficient manner. It is thought that there is little in the way of pollution control along these road drains, particularly the smaller roads/tracks.

Fine sediment may be effectively transported to the river system via both the point and diffuse sediment sources detailed above, particularly those with influence of anthropogenic practices.

(a) (b)

(c)

Figure 5.13 (a) Outfall structures; (b) Poaching of the river bank; (c) Tilled agricultural land adjacent to the river

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Figure 5.14a Diffuse and point sediment sources observed during fieldwork on the River Lugg

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Figure 5.14b Diffuse and point sediment sources observed during fieldwork on the River Lugg

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Figure 5.14c Diffuse and point sediment sources observed during fieldwork on the River Lugg

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Figure 5.14d Diffuse and point sediment sources observed during fieldwork on the River Lugg

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5.5 Geomorphological Function and Processes

The majority of the Lower Lugg (61% of reaches) has been characterised as sediment transfer zones, with the 27% of reaches acting as sediment exchange zones. The remaining 8% of the reaches are either a source or sink of sediment (data recorded from aerial photography, spot checks and bespoke fluvial audits, see Figure 5.15).

Those reaches marked as sediment transfer zones displayed few signs of erosion or deposition. Those reaches classed as exchanges exhibited areas of both erosion and deposition in a close vicinity, acting to exchange the sediment within the reach.

These findings were observed using aerial photography and whilst completing the bespoke fluvial audits and spot checks; however, as water levels were high during the January/February 2014 surveys these findings were not verified by visual observations throughout. The historical map analysis supports the findings of a dominant function of a sediment transfer, with few depositional features mapped and little channel change seen over a 120 year period.

Figure 5.15 Dominant geomorphological function of the 26 reaches of the Lower Lugg. Note: information was extracted from aerial imagery and data from the spot checks and fluvial audits. The percentages do not represent river length as the reaches are not of equal length.

The Lower Lugg reflects a stable channel, with almost 60% of the reaches exhibiting a stable geomorphological process (Figure 5.16). There has been some channel migration of the Lower Lugg, particularly in LUGG002-006 and LUGG026, along with historical map evidence of channel migration in the Lugg. This is reflected in there being 37% of the river recorded as laterally adjusting (Figure 5.16).

Combining the historical analysis with the surrounding topography, it suggests that despite the presence of depositional and erosional features there is little movement of the channel boundaries, particularly downstream of Leominster. The rate of

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erosion appears to be slow and the depositional features probably reflect an in- channel morphological adjustment in response to a naturally fluctuating sediment and flow regime. The presence of embankments on both banks in some of the lower surveyed section could also be confining the rivers ability to migrate significantly.

Figure 5.16 Dominant geomorphological processes for the 26 reaches of the Lower Lugg. Note: information was extracted from aerial imagery and data from the spot checks and fluvial audits. The percentages do not represent river length as the reaches are not of equal length.

Figure 5.17 shows the geomorphological processes and functions for each of the reaches, to highlight the variation across the catchment.

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Figure 5.17a Geomorphological function (a) as assessed from the River Lugg surveys

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Figure 5.17b Geomorphological process as assessed from the River Lugg surveys

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6 Catchment Pressures and Ecological Condition

This section provides an overview of the catchment pressures and the ecological condition of the River Lugg. These are then discussed in full in the Management Report.

6.1 Catchment Pressures

The main pressure identified along the Lower Lugg (Presteigne to the confluence with the River Wye) is the impact of land use adjacent to the river. The Lugg and its surrounding floodplain are linked systems and therefore activities carried out on the floodplain may have a number of impacts on the river channel. Widespread degradation of the riparian zone was noted during the spot checks and bespoke fluvial audits, and this may also be seen through aerial photography.

The key pressures and modifications identified on the Lower Lugg from the spot checks, bespoke fluvial audits and desk study are listed below:

 Degradation of riparian zone (widespread);  Land use;  Bank protection (mainly through urban areas);  Embankments;  High levels of sediment within main channel;  Poaching by stock (frequent);  Resectioned banks (frequent through agricultural land, particularly near urban areas);  In-channel structures (e.g. weirs, bridges);  Invasive non-native species; and,  Lack of floodplain connectivity and storage.

The main pressures have been described below under four generic groupings, modifications, sediment, riparian zone degradation and flood storage. Table 6.1 details the primary modifications for each of the reaches.

Where flow regulation or abstraction is an issue (in particular SSSI Units 3, 2 and 1) this may potentially have adverse downstream impacts on species. For example, a Sniffer (2012) study describes the ecological indicators of the effects of abstraction on flow regulation in a series of conceptual models. There are many studies over the past five decades describing impacts of altered flow regimes on hydraulics and morphology and in turn on macroinvertebrates, fish and macrophytes. However, as this restoration vision is directly concerned with morphological impacts it only considers flow regulation as a baseline condition. Section 4.5 provides a background of the water resources and quality along the River Lugg. It should be noted that river restoration alone will not help to solely achieve favourable condition; measures to address water quality and flow would need to be continually applied following any river restoration implemented.

Whilst this restoration vision focuses on sustainable management of the fluvial geomorphology and river habitats of the River Lugg, a holistic approach to river restoration needs to be taken in order to achieve favourable condition status. River restoration alone will not achieve favourable condition for the Lugg, nor will it improve sections failing ‘good ecological status’ under WFD. River restoration will

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contribute to an overall set of actions that also tackle issues such as water quality, diffuse pollution and sustainable abstraction and discharge consents using a catchment based approach.

6.1.1 Modifications

Modifications such as hard bank protection, bridges (approximately 50 in total) and embankments limit the capacity of the channel to laterally adjust. This may alter the sediment regime, morphology and flow dynamics of the river. A result could be accelerated erosion in some places or increased deposition in others. Any deviation from the natural equilibrium of sediment dynamics could remove habitats or adversely alter them. Artificial hard points also disconnect sediment input from channel banks, potentially depriving adjacent and downstream reaches of valuable sediment supply. As well as disconnecting sediment supply, there is a direct loss of habitat. In-channel structures may also alter flow and cause erosion where it would not naturally occur.

Weir structures may have a significant impact on the river channel both directly as a result of the structure and indirectly up- and downstream. The physical structure impacts the bed and banks of the channel, acting to alter the sediment (including the reduction of gravel supplies downstream) and flow regimes, morphology and fish movement within the river. Weirs are also normally associated with bank reinforcement for short distances upstream and downstream, having similar impacts to those discussed above.

A weir structure may also cause flow to back up upstream encouraging sediment deposition (particularly fine sediment) and creating an area of slower flow. This is likely to impact the natural regime of the channel and may cause fine sediment to smother gravels where the flows are reduced. Where gravels become smothered, this may reduce potential viable spawning habitats for fish species. Downstream of weir structures, scour pools are usually present. These are as a result of a change in the flow dynamics, channel gradient and sediment input to the downstream section of the river. Although scour pools may provide varied habitat for fish locally (i.e. deep pools and clean gravel deposits), they alter the characteristics of the channel including impounding water upstream and are normally significantly wider than the natural channel (Figure 6.1).

Scour pool

Weir

Bank reinforcement Figure 6.1 Weir pool from fluvial audit upstream of Leominster

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6.1.2 Sediment

High sediment loading was observed in the Lower Lugg at the time of survey, particularly where adjacent land use was tilled arable fields and at the confluence with tributaries (e.g. the River Arrow at Stoke Prior; Figure 6.2). The high sediment load is likely to be sourced from the adjacent agricultural land which has insufficient riparian buffer zone to trap sediment carried in hill slope runoff before it reaches the main channel. There were many locations along the Lower Lugg where degraded riparian buffer zone was observed.

Figure 6.2 River Arrow (red arrow) confluence with the River Lugg (blue arrow)

Although high fine sediment levels are temporary in high flows, as observed at the time of the January/February surveys, this is likely to have a detrimental impact on species requiring clean gravels, such as shad, lamprey, bullhead and white-clawed crayfish when the sediment settles out downstream. Most fish are impacted by fine sediment if it results in spawning grounds becoming choked. In addition, deposition of fine sediment may also impact on in-stream invertebrate communities as well as flora. As well as high levels of fine sediment impacting upon physical habitats, it also acts as a direct pollutant to the watercourse and is a pressure identified in the Severn RBMP. Some natural channel erosion is expected within a river system providing a natural source of fine sediment and this should not be prevented; however, excessive input of fine sediment may be detrimental to the existing ecological and geomorphological habitats.

Poaching (trampling of banks by stock) in the Lower Lugg was observed to be relatively extensive. Poaching may lead to fine sediments and excrement entering the watercourse which is also detrimental to species requiring low silt levels, such as the white-clawed crayfish. A number of actions for dealing with water quality are summarised in the Severn RBMP.

6.1.3 Riparian Zone Degradation

Riparian zone degradation was extensive throughout the Lower Lugg (Figure 6.3). The Lugg was observed to have large sections of the river with no riparian zone; where a riparian zone was present it had a degraded structural complexity. The riparian zones primarily consisted of trees of a similar type and age, with a limited range of vegetation types and composition.

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Riparian zone degradation and poaching not only lead to elevated fine sediment levels within the channel, but also means that there are less marginal habitats for species relying on shade and cover from predators. The species that could be impacted by this are the otter, white-clawed crayfish, trout, grayling, lamprey, bullhead, shad and salmon. In addition, the low level of channel shading results in higher water temperatures in the summer, which will have an increasingly negative impact upon the biological communities of the river with the effects of climate change. Increasing channel shading where appropriate is a key climate change adaptation measure on rivers, especially those with a north-south orientation to facilitate the northerly migration of species along the river corridor, such as the Lower Lugg (Aymestrey to the Wye confluence).

A lack of riparian vegetation could limit a key food source for in-channel biotic communities, by removing inputs such as detritus (leaf litter and other organic material) which particular species of invertebrates (detritivores) require. Riparian zone degradation may also limit terrestrial invertebrates within the system by removing access from overhanging vegetation.

The lack of a complex riparian structure also leads to a poor root structure which may make the river banks prone to accelerated erosion. In association with this, if a riparian corridor is predominantly grass or shrub, the root systems tend to be shallow and less extensive and may die back in winter months, again leaving the bank prone to accelerated erosion.

A lack of a wooded riparian zone may also limit the availability of woody material supply into to the channel, which is a natural process that provides habitat and flow diversity and also may act to trap some fine sediment and create areas of deposition. Without a complex vegetation structure in the riparian corridor, woody habitat is not present within the river channel and there is no supply of woody habitats for the future. In addition, habitat for the insects that fish eat is reduced and it is likely to be easier for non-native invasive species to colonise the river banks where native riparian vegetation is absent.

Furthermore, a lack of riparian vegetation exposes river banks to higher rates of erosion. This is due to the lack of root structure binding the soil thus reducing resistance to erosion processes. The absence of riparian vegetation is common within agricultural landscapes with tilled land or grassland right up to the river bank. Shallow rooting grasses and crops provide little soil binding which is typically restricted to the surface soil horizon. Consequently there is no deep soil root binding that would be present with established riparian vegetation. The potential for accelerated erosion may result in higher rates of lateral channel migration than would naturally occur (established riparian vegetation which exerts a control on lateral erosion). This accelerated erosion of the banks also introduces fine sediment (soil) into the river channel, which has a detrimental impact on river habitats (see Section 6.1.2).

Where the tree lining is limited to individual scattered trees this also leaves the bank susceptible to significant impacts from diseases such as Phytophthora (described in 4.10.5). If trees begin to die back in these instances, no riparian corridor remains, leading to an unstable bank and the potential for accelerated erosion. As well as this, single tree linings typically consist of similar aged trees which are likely to get old at the same rate or succumb to disease, with no effective regeneration taking place.

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Figure 6.3 Lack of riparian zone along the Lower Lugg

6.1.4 Hydrological Connection between River and Floodplain

Many sections of the Lower Lugg are incised as a result of historical dredging practices (see Section 5.1.2), as a result the river is disconnected from its floodplain and water passes through the system quickly. Although some flood alleviation schemes along the Lugg have been implemented to slow down the water and create some areas of storage, this is only in small localised areas.

Wet woodland habitat was observed along Fluvial Audit 5 between Eyton and Leominster (LUGG008-013), but this only covered a small section of the surveyed reach (Figure 6.4). As a result of the high river flows at the time of survey, the wet woodland was inundated and it could be seen how these areas could provide a flood storage benefit to the area by preventing these areas from flooding into the agricultural fields on the opposite bank.

Natural features, such as backwaters and wet woodlands, provide natural storage of water in high rainfall events and provide habitat diversity and suitable habitat (refugia) for fish in higher flows. Reconnection of the river with its floodplain may also have multiple flood risk benefits, including: providing natural flood water storage adjacent to the river and allowing siltation in the floodplain removing fine sediment from the system. A semi-natural functional floodplain increases roughness and friction. This acts to further reduce flow velocity when the channel spills onto the floodplain thus reducing peak flows and flood risk downstream.

Figure 6.4 Wet woodland on the alternating banks observed on the Lower Lugg during fluvial audit 5 (LUGG008-013)

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Table 6.1 Morphological pressures affecting the reaches of the Lower Lugg (where grey = none; red = extensive >33% of the reach and orange = present <33% of the reach). The presence of these pressures is used as an indicator of restoration potential Habitat Modifications Sediment Lack of Number Modification Riparian Natural SSSI High fine Reach ID of RHS Class (at Weirs Reinforced Zone Flood Unit Bridges sediment Poaching sites each RHS bed/bank Degradation Storage site) LUGG001 4 0 LUGG002 4 1 3 LUGG003 4 0 LUGG004 4 0 LUGG005 4 0 LUGG006 3 0 LUGG007 3 0 LUGG008 3 1 1 LUGG009 3 0 LUGG010 3 0 LUGG011 3 0 LUGG012 2 1 5 LUGG013 2 0 LUGG014 2 1 3 LUGG015 2 1 5 LUGG016 1 0 LUGG017 1 1 1 LUGG018 1 1 2 LUGG019 1 0 LUGG020 1 0 LUGG021 1 4 3, 2, 5, 1 LUGG022 1 1 3 LUGG023 1 1 2 LUGG024 1 5 2, 4, 2, 2, 2 LUGG025 1 1 2 LUGG026 1 1 3

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6.2 Effect of Physical Habitat Modifications on Ecological Condition

Physical modifications are regular along the length of the Lower Lugg. Modifications such as hard bank protection and weirs may have a detrimental impact on physical forms and process and associated aquatic habitat and quantity and diversity of aquatic flora and fauna. Table 6.2 details the impact of physical pressures found on the Lower Lugg and the associated effects on hydromorphology and habitats.

Table 6.2 Impacts of physical pressures found of the Lower Lugg Pressure (Physical Effect Mitigation measure Modification) Hard bank protection Loss of riparian zone/ Removal of hard bank (e.g. steel piling, marginal habitat / loss of reinforcement. Revetment, vertical walls) connectivity/ loss of or replacement with soft sediment input/ loss of flow engineering solution energy absorbance Preserve and where possible enhance ecological value of marginal habitat, banks and riparian zone Preserve and, where possible, restore historic habitat Weirs Loss of sediment continuity Operational and structural – build-up of sediment changes to weirs upstream, reduced bedload downstream Loss of biological Installation of fish passages continuity – interference with fish population movements Realignment Loss of morphological Increase in-channel diversity and habitat morphological diversity

Sediment Direct loss of/ impact to Sediment management management aquatic habitats/ strategies (develop and (dredging) hydromorphology revise) Transfer of fine sediment downstream Bankside erosion and impacts to riparian habitats Source of fine sediment (disposal of dredgings on banks) Vegetation control Physical disturbance of Selective vegetation control bed and/or bank – regime increased sediment Appropriate vegetation mobilisation and loss of control technique marginal/riparian Appropriate timing vegetation Transfer and establishment Appropriate techniques of alien invasive species (invasive species) Culverts Loss of morphological Reopening existing culverts

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diversity and habitat Alteration of channel bed Continuity Reopening existing culverts Alteration of channel bed Flood banks and flood Loss of riparian zone / Flood bunds walls marginal habitat / loss of Set back embankments lateral connectivity / loss of Improve floodplain sediment input connectivity Removal/clearance of Loss of aquatic habitats Appropriate channel urban trash and maintenance strategies and woody debris techniques e.g. minimise disturbance to channel bed and margins Transfer of fine sediment Appropriate channel downstream maintenance strategies and techniques e.g. remove woody debris only upstream of, or within, areas of urban flood risk Pipes, inlet and Hydromorphological Appropriate techniques to outlets alterations of water and align and attenuate flow to sediment input through limit detrimental effects of artificial means these features

There are still a large number of weirs along the Lower Lugg (approximately 30 in total; Hyder, 2010). Although some fish passes have been implemented which has improved the situation over the last decade, the weirs along the river may act as a barrier to fish movement. Fish passes do not enable fish passage at all times, with low flow periods still limiting the ability of fish to use the structures. Weir removal would be preferred within the catchment, but is not always feasible or appropriate (discussed in detail in section 7.3.2). However, the complete removal of weir structures could impact on native species such as white-clawed crayfish, by enabling migration of invasive non-native species from the lower reaches.

Bed substrate could not be observed in all reaches. From the sites that were observed and the relative lack of channel modifications (especially in the rural areas) along the Lower Lugg, it is suggested that natural bed conditions would not deviate significantly from the visions set out in Mainstone (2007) for river Types I, II and VI. From these visions it is not expected in sections of the river with low gradient (Types I and II) that there would be significant salmon spawning grounds; these would be further upstream on the Lugg or in its tributaries. Where the river has a slightly steeper gradient (i.e. sections upstream of Hope-under-Dinmore), the river exhibits more of a Type VI community type and may contain suitable spawning ground for salmon through the creation of in-channel features such as exposed shingle bars and diversity of flow types. However, the potential weir barriers could limit the presence of the species.

Gravels in the lower gradient section of the Lower Lugg were observed during the bespoke fluvial audits and the spot checks, with pebbles and cobbles also present. River gravels and coarse substrate such as this are essential for SAC species including lamprey spp., bullhead and other non-SAC macro-invertebrate and fish species.

Following the spot check and bespoke fluvial audits, the physical-habitat suitability for SSSI and SAC species have been summarised in Table 6.2. Some of the spot

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checks and bespoke fluvial audits were carried out during periods of high flow which have obscured many of the habitat features, although some sites were revisited in lower flow conditions, some of the results should be viewed with that in mind. Where possible, desk study information has been used to supplement and enhance site observations to determine habitat suitability.

The River Lugg was observed both during field surveys and historical analysis to have been modified throughout the catchment, with the most extensive morphological pressure being the presence of weirs, with some historical straightening and dredging. A number of sites would benefit from restoration measures/actions being implemented, which would begin to provide an overall improvement on a catchment scale. It should be noted that following the 2014 survey work, the river was found to have some reaches exhibiting habitat suitability for aspects of the SSSI and SAC biological communities and species.

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Table 6.2 Habitat suitability on Lower Lugg Suitable Habitat Present SSSI Habitat Requirement (from field surveys) Feature or SAC (as detailed by guidance) Spawning Larvae/juvenile habitat habitat Adult habitat SAC Watercourses Fast flow conditions of riffles, runs and glides. Present of plain to Gravel, pebble and cobble substrate. Low shade During the survey undertaken in October in lower flow montane levels and influence of grazing. High bed/bank stability. conditions, suitable habitat was observed. This with the included features such as riffles and a diverse range of Ranunculion From Hatton-Ellis and Grieve (2003). flows. However, there were also areas of limited fluitantis and suitable habitat observed. Riparian zone degradation is Callitricho- present throughout most reaches. Batrachion vegetation SAC Sea lamprey Water depth: Variable. Present* Present* Present Petromyzon Velocity: Variable. marinus Channel: Large streams/rivers. Pollution sensitive. Shallower Numerous However, weirs Spawning: Temperatures <15oC. Medium flow. reaches/ deposits through may act as Gravel (9.5-50.8mm in diameter) with some sand channel margins Lower Lugg barriers to fish content. Tails of pools. with faster flow catchment. movement. Larvae: Low velocity (0.2-0.3m/s) near edge of run-riffle However, shading streams/rivers. Clay, silt sand substrate with high characteristics. is limited. organic content. Shade. Stream gradient 1.9- 5.7m/km. Slowing current where deposition of silt and sand occur. 30cm deep substrate. Adult: Suitable spawning areas.

SSSI/ Brook lamprey Water depth: Variable. Present (in Present Present* (in SAC Lampetra Velocity: Variable. lower sections) lower sections) planeri Macrophytes: Some (during larval stage) Channel: No barriers to migration. Average gradient Shallow reaches Likely to have silt Some in- 0.2-0.6m/km. Pollution sensitive. with faster flow deposits in lower channel Spawning: Water depth usually 3-30cm. Near edge run-riffle flows (extent vegetation of stream/rivers. Temperatures between 10-11oC. characteristics; undetermined). observed; Stones and gravel substrate. Lower end of pools. however, weirs however, Larvae: Flow 0.5m/s. Mud, silt, or silt and sand may act as shading is substrate with high organic content. Some barrier to minimal and macrophytes. migration. weirs may act Adult: Stones and vegetation to hide among. as barriers to

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Suitable Habitat Present SSSI Habitat Requirement (from field surveys) Feature or SAC (as detailed by guidance) Spawning Larvae/juvenile habitat habitat Adult habitat Suitable spawning areas. migration.

SSSI/ River lamprey Water depth: Variable. Present Present Present SAC Lampetra Velocity: Variable. fluviatilis Channel: No barriers to migration. Average gradient Shallow reaches Likely to have silt Run habitats 0.2-0.6m/km. Pollution sensitive. with faster flow deposits present observed. Spawning: Water depth usually 20-150cm. Flow 1- run-riffle (extent 2m/s. Near edge of stream/ rivers. Temperatures characteristics. undetermined). between 8.5-12.0oC. Variable particle size, normally gravel with sand (at tails of pools). Larvae: Low velocity (<10cm/s). Mud, silt, or silt and sand substrate with high organic content. Adult: Short runs with suitable spawning areas. SSSI/ Twaite shad Water depth: 50-70cm. Present* Present Present SAC Alosa fallax Velocity: Variable. and Allis shad Macrophytes: Some (all life stages). Deep pools Riparian zone is Alosa alosa Channel: Juxtaposition of life stage habitats. present, limited which may Spawning: Clean, stable gravel/pebble substrate. required for reduce shading Larvae: Cover essential (e.g. vegetation and spawning. and cover. undercut). Adult: Deeper water for holding pools and undercut banks to protect from predators. SSSI/ Atlantic salmon Water depth: Variable. Present* Present* Extensive* SAC Salmo salar Velocity: Variable. Macrophytes: Some (all life stages). Limited to Shallower Deeper runs Channel: Juxtaposition of life stage habitats. shallow reaches reaches with and pools for Spawning: Gradient <3%. Velocity 25-90cm/s. with faster flow faster flow run- adults to hold Water depth 17-76cm. Cobble/ pebble substrate (2- run-riffle. riffle up in. Fine 256mm diameter) with <20% fine sediment. characteristics; sediment inputs Transitional zone between pool and riffle where flow fine sediment in some accelerates and depth decreases. Cover important input in some reaches may Larvae: Water depth <20cm. Flow 50-65cm/s. reaches may limit limit suitable Gravel/cobble substrate (16-64mm diameter) and suitable habitat. habitat. cobble/boulder substrate (64-256mm diameter). Cover essential (e.g. loose substrate, large rocks, Some reaches undercut banks, overhanging vegetation, aquatic were tree lined

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Suitable Habitat Present SSSI Habitat Requirement (from field surveys) Feature or SAC (as detailed by guidance) Spawning Larvae/juvenile habitat habitat Adult habitat vegetation). providing cover Adult: Deeper water for holding pools. Downstream (bank/ marginal). of spawning gravels. Water depth also (Hendry and Cragg-Hine, 2003) provides cover. SSSI/ Bullhead Water depth: >5cm. Present* Present* Present* SAC Cottus gobio Velocity: Moderate. Macrophytes: <40% Planform Channel: Sinuous, pool-riffle sequence, naturally sinuous in most wooded riparian margins, exposed roots in the sections; channel. however, lack of Breeding: Coarse substrate with large stone. naturally Larvae: Shallow, stony riffles. wooded riparian Adult: sheltered sections (debris, tree roots, margins in some macrophyte cover or large stones). reaches.

From Tomlinson and Perrow (2003) SSSI/ European otter Adequate fish biomass to provide food resource. Present SAC Lutra lutra Presence of exposed tree roots and cavities. Cover (riparian vegetation). Good foraging habitat. Riparian vegetation sparse in a lot of sections on the Lower Lugg; however, some (Chanin, 2003) wooded areas are present and sections of continuous tree lining. SSSI/ White-clawed Water depth: Typically 0.75m to 1.25m deep. Present SAC crayfish Macrophytes: Some (all life stages). Austropotamob Channel: Vertical banks, pool-riffle sequence, Suitable habitat observed in Lower Lugg. Could ius pallipes naturally wooded riparian margins, exposed roots in potentially benefit from more woody debris the channel, wood debris accumulations. All life accumulations. However, woody debris must not stages need shallow water with a rocky substrate interfere with navigation rights and associated health and soft banks for burrows. and safety issues. Poaching was observed, with a lack (Holdich, 2003) of riparian buffer, which is detrimental to this species. SSSI Type VI Rivers Width: Not exceeding 10m. Present on sandstone, Substrate: Typically a combination of both soft mudstone and sandy substrates and gravels and pebbles. Riparian zone is not extensive. However, some hard limestone Banks: Usually soft and steep and tree cover is suitable habitat is present and the river is reaching a common. more natural width in some locations. Flow regime was varied in some reaches.

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Suitable Habitat Present SSSI Habitat Requirement (from field surveys) Feature or SAC (as detailed by guidance) Spawning Larvae/juvenile habitat habitat Adult habitat SSSI Type I Fast Flow: A stable flow regime over diverse substrates. Present (in a localised areas). flowing Channel: Shallow banks. calcareous small rivers on mixed substrates SSSI Type II Clay Substrate: A combination of clay, sand, gravels and Present (in sections from Leominster to Mordiford). rivers with cobbles. diverse Flows: Areas of sluggish flows. Sparse covering of marginal vegetation may act as a substrates and limit. flow patterns SSSI Pilwort Shallow moorland pools. Not present

Confined to the source pool, outwith the study area of this assessment. SSSI Pea Mussel Habitat: Requires unpolluted conditions, usually in Unlikely to be present slow flowing reaches. There are high levels of fine sediment input in sections of the Lower Lugg which may limit the areas with ‘unpolluted conditions’. Flow in high rainfall events is uniform, with few slow flowing reaches present. SSSI Aquatic Habitat: Live in stones in flowing water. Has an Present beetles/alder aquatic larvae living in silts in large river systems. fly SSSI Allis shad Habitat: Shallow coastal waters, but during Unlikely to be present spawning migrates to the lower and middle reaches of large rivers. Juveniles feed on bottom living There are barriers to fish migration and some fine invertebrates. Adults feed in salt water. Mature Allis sediment pollution within the Lower Lugg. shad run up into river during late spring and spawning takes place in suitable pools. * Due to the high flow conditions at the time of the February 2014surveys, it was not possible to observe these habitat requirements in certain reaches; however, some sites were revisited in October 2014 and this information has also been derived from aerial photography or other desk study sources including the Halcrow (2012) study, CCW Core Management Plan (Dyson, 2008) and the JNCC website (JNCC, 2013)

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7 Restoration Potential

7.1 Summary of Restoration Potential

The current form of the river channel in the Lower Lugg is a function of the underlying geology, topography, climate, land use and abstraction activities. The main modifications observed on the Lower Lugg have been identified in Section 6. The majority of the Lower Lugg shows signs of recovering morphology, with areas of active meanders, deposition and erosion and varying flows and substrates. Reaches where the morphology was recovering were observed to include natural geotechnical failure and erosion of resectioned banks.

The possible restoration solutions available for the Lower Lugg have been developed using professional knowledge and experience following: the site visits undertaken during January/February and October 2014 and analysis of photographs taken, data collected on site visits, data mapped by Hyder (2010) and RHS surveys (1994-2007). This also included review of the UK River Restoration Centre Manual of River Restoration Techniques and Mainstone (2007) ’rationale for the physical restoration of the SSSI river series in England’ paper.

JNCC (2014) guidance states that where a site has been notified as an example of a high quality river, the aim of the SSSI designation is to “conserve the habitat for the characteristic communities of the river.” Therefore, the strategy should be to support the conservation of high quality sites, using characteristics outlined in Table 3.3, as well as restoring sites where anthropogenic morphological pressures exist. Full ‘restoration’ of sites may not be possible due to topographical and legitimate land use constraints, such as valley sides and transport infrastructure, but restoration of the sites should be attempted where feasible.

The key pressures identified on the physical habitat of the Lower Lugg are:

 Degraded riparian zone;  Bank and channel modification;  High level of fine sediments;  Embankments;  Weir structures;  Land use;  Floodplain connectivity and storage; and,  Invasive non-native species.

The re-establishment of natural river processes and form is in line with the objectives of the CCW catchment management plan as is the modification of artificial factors such as bank protection that affect SSSI/SAC features. Riparian zone improvement will partially address water quality issues arising from diffuse pollution as this would increase the width and variety of flora within the buffer zone at the land/ water interface. Appropriate changes to land management practices adjacent to the river would also address issues of sediment input and water quality.

The re-establishment of natural river processes is also compatible with the CFMP policies to promote natural flood risk management approaches where possible. Promoting floodplain connectivity where feasible and increasing length and diversity (which may arise from bank protection removal) will help to attenuate flood flows

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downstream. Recommendations to improve flood storage in some of the reaches will also contribute to the CFMP (i.e. backwaters).

Some initiatives such as High Level Stewardship (HLS)10 in England and Glastir in Wales may be used to support changes to farming practices to improve water quality and encourage natural flood risk management, which may include large buffer strips and livestock fencing, and reconnecting the river and floodplain.

7.2 Potential Restoration Measures

To restore favourable condition in the Lower Lugg, assisted natural recovery will be promoted wherever possible, i.e. allowing natural channel movement and processes where present (including deterioration of bank protection and erosion of embankments and flow deflectors). Assisted natural recovery may also include reducing or ceasing channel maintenance where it does not have a detrimental impact on flood risk. These measures may be low cost or involve cost savings provided that suitable incentives are available to support associated land management changes where required.

Where more active restoration is required, potential restoration measures may be grouped into five classes as follows:

1) Riparian buffer and woodland regeneration  Improve riparian zone to reduce accelerated sediment supply, to provide more shade to the channel to benefit fish and to provide the means for large woody debris accumulation downstream which will enhance riverine habitats and flow types (where the introduction of woody debris will not negatively impact on flood risk and recreational pursuits, such as canoeing).  Increasing riparian vegetation would also enhance allochthonous organic input which may benefit larval lampreys.  Improve the buffer strip along the river between the surrounding land use; improving fine sediment in the channel and water quality.  Creation of woodland and wet woodland within the floodplain. Where feasible, this should be tied in with adjacent areas of woodland or woodland creation for the wider catchment.  A catchment wide plan would provide full potential benefits, with some measures being implemented outside of the floodplain zone.

2) Weir removal  Removal of hard bank protection associated with these structures, allowing natural channel adjustment.  Complete weir removal to removing barrier to fish movement; improve the longitudinal and lateral connectivity of the channel at these localised points; improve flow diversity; increase habitat diversity and habitat connectivity.  Where complete weir removal is not viable, other methods should be considered including: weir bypasses (such as bypass channels which also provide potential for greater habitat creation), fish pass implementation (e.g. Larinier fish pass); alteration of weir structures to accommodate/improve weir structures (e.g. addition of booms, lowering of hydraulic head differential and installation of brushes or baffles) or partial removal of weir structures.

10 HLS is due to be replaced under reform of the CAP. It is likely that the new scheme under the Rural Development Programme 2014-2020 will be a Countryside Stewardship

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3) Land management measures  Encouraging farmers to plough the furrows of tilled fields parallel to the river (as opposed to perpendicular) to reduce runoff directly channelled into the river.  Provide measures to interrupt the sediment delivery pathways from agricultural land to the river corridor. Measures could include the use of buffer strips, ponds or other wetland habitat creation, woodland/wet woodland creation.  Prevent poaching of the river banks and access to the water edge (e.g. reduce stock densities, providing drinking troughs elsewhere or restrict grazing at specific times to allow the establishment of riparian vegetation).  A catchment wide plan would provide full potential benefits, particularly by altering the practices in- and outside of the floodplain zone.

4) Channel cross section enhancements  Bioengineering in urban areas where other measures are not applicable.  Retain or introduce woody material to encourage flow diversity and habitat heterogeneity within the channel (where the introduction of woody debris will not negatively impact on flood risk and recreational pursuits, such as canoeing).  Reprofiling of channel cross section to soften the bank slopes, often asymmetrically, and provide some variation within the profile which can assist natural recovery and encourage marginal vegetation and wildlife habitat opportunities.

5) Removal/breaching of embankments  Remove, set back or breach embankments to restore floodplain connectivity and function where this action does not conflict with the CFMP policy for the Unit.

6) Hydrological connectivity and floodplain storage  Integral as part of the mitigation measures suggested above in Options 1-5.  Creation of backwaters to encourage not only areas of flood storage within the river corridor, but also to create habitat and flow diversity within uniform sections of the river.  Creation of wet woodland habitat, slowing flow of water into the channel, and providing enhanced riparian zones and areas with flood storage capacity.  Measures to slow peak flow; e.g. leaky dams that enable temporary storage of flood flows in a designated area whilst enable water to still pass through the system.  Re-naturalisation of the existing floodplain, including reintroducing historic floodplain characteristics.

7.3 Descriptions of Restoration Measures

The following provides more detailed explanations of the restoration measures proposed in Section 7.2. The likely locations of these measures and further information may be found in the Management Report. These restoration measures have been established to improve the condition of the River Lugg SSSIs and the River Wye SAC as well as trying to improve/maintain the WFD status of the water bodies and support flood risk reduction measures.

Table 7.1 provides a summary of the potential benefits each of the restoration measures could have on river process, morphology and ecology.

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7.3.1 Riparian Buffer and Woodland Regeneration

Increase riparian trees and scrub to encourage a buffer strip to develop along the river banks. Although parts of the catchment have some coverage of trees, and there are woodlands near to the river, an absence of trees and presence of simple vegetation (semi-improved grassland) along the majority of the reaches of the Lower Lugg was recorded. Absence of trees along the river edge reduces the sources of woody debris, leaf litter and exposed tree roots, which provide submerged habitat for fish and invertebrates. Poor riparian vegetation also makes the banks more prone to erosion, thus increasing sediment supply of the river and may result in accelerated bank erosion and consequent channel migration. The co-occurrence of tree lined and open sections is likely to be important for a range of invertebrate species.

Improvement works may also be undertaken in tributary catchments, particularly the River Arrow and River Wye, as these were noted as potential sediment sources during the field surveys. The enhancement of the tributary catchments could potentially remove key pathways of sediment input into the River Lugg catchment. Measures for natural flood risk management within the tributaries will also deliver the benefit of reducing peak flows and flood risk within the Lugg catchment.

7.3.2 Weir Removal or Modification

Weir removal or modification (i.e. lowering or bypassing) will primarily improve the longitudinal and lateral connectivity of the River Lugg. Weirs may act as a barrier to longitudinal sediment transfer, alter local flow regimes and act as a barrier to fish movement. Weir removal would aim to reconnect the longitudinal and lateral sediment and flow pathways, re-establishing the channel bed and banks (including gravel substrates). Weir removal or modification may also remove the potential barriers to fish movement, aiming to encourage migration upstream and enhance habitat connectivity. However, complete weir removal could have the potential to enable the accelerated spread of signal crayfish in areas where native crayfish are known to be present. Weir removal in tributary catchments could also improve the availability of varying habitats that could provide suitable conditions for the different stages of fish species, as well as providing additional locations for other fauna to colonise.

Where complete weir removal is not viable, other methods should be considered including: weir bypasses (providing potential for greater habitat creation), fish pass implementation (e.g. Larinier fish pass); alteration of weir structures to accommodate/improve weir structures (e.g. addition of booms, lowering of hydraulic head differential and installation of brushes) or partial removal of weir structures.

7.3.3 Land Management Measures

Land management measures aim to encourage best practices in the land surrounding the River Lugg. The measures will look to work with farmers to alter some of the land practices currently being undertaken in close proximity to the river’s edge, including the following:

 Re-directing tilled fields to run parallel with the river as to not encourage runoff to flow directly into the river channel;  Providing an area alongside the river’s edge that isn’t worked for agricultural purposes, creating a buffer strip and interrupting sediment delivery; and,

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 Create specific watering areas for cattle or reduce access to the river edge for periods of time to reduce poaching impacts on the river channel.

In particular, Catchment Sensitive Farming, a scheme run by Natural England in partnership with the Environment Agency and DEFRA, raises awareness of diffuse water pollution from agriculture. The scheme gives free training and advice to farmers in selected areas of England on topics including manure, nutrient and pesticide management, soil condition and farm infrastructure. Agri-environmental schemes also encourage environmentally sensitive farming through providing annual payments to farmers and land agents to ensure they manage their land in a way that goes beyond the minimum required of them by regulation. The Wye and Usk Foundation has also worked extensively with farmers to develop successful methods of working and delivering water quality improvements.

Each of these schemes will work towards reducing the levels of diffuse sediment pollution that is passing into the river channel as well removing physical pressures on the river banks. These approaches may be used to reduce input of sediment and nutrients, to establish a zone of more natural riparian vegetation and to help reduce potential flood and erosion risks. Pressures from the river banks were observed to be one of the key issues along the river channel and with a lack of riparian buffers the impacts of these were amplified. The reduction of fine sediment reaching the channel will act to improve the bed substrate, fish spawning habitat and ecological habitat.

Implementing land management measures throughout the tributary catchments that form part of the River Lugg catchment would further increase the potential benefits by removing key sources of sediment pollution to the River Lugg.

7.3.4 Channel Cross Section Enhancements

Channel cross section improvements through techniques such as bioengineering could be utilised in reaches that are heavily constrained (e.g. in urban areas) and where other techniques such as resectioning (described below) are not possible. Bioengineering is the combination of biological, mechanical and geomorphological concepts to control erosion, stabilise banks and provide diversity within the river channel. This may be focused where there are restrictions on the restoration possible in the channel and uses innovative techniques such as floating edge ecosystems (i.e. riparian habitat baskets/islands). This will act to enhance the channel cross section without impacting on the flood risk of the areas, encouraging vegetation development providing fish habitat. The introduction of woody debris, where appropriate, into the river channel may also be considered as it encourages flow diversity and creates habitat heterogeneity.

Cross sectional reprofiling could also be utilised to alter the river bank slope, usually where the banks are excessively steep (possibly eroding) or have been reinforced or modified (often in urban areas). Bank protection can also be implemented as a flood defence or meander stabilizing measure. The reprofiling alterations may be to soften the bank slopes, often asymmetrically, and provide some variation within the profile which can assist natural recovery and encourage marginal vegetation and wildlife habitat opportunities.

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7.3.5 Removal/Breaching of Embankments

The removal or breaching of embankments provides a means of re-establishing floodplain connectivity and may be combined with cross-sectional enhancements (detailed in Section 7.3.4). This would enhance the lateral connectivity in localised sections and encourage floodplain processes as well as riparian habitat corridors to be established. In association with embankment removal, bank reprofiling may also take place if the embankments are along the river edge. This looks to enhance areas where morphological diversity and habitat diversity may have been removed. Enhancing the existing trapezoidal channels in some of the reaches will aim to create non uniform bank profiles and assist natural recovery within the channel.

7.3.6 Hydrological Connectivity and Flood Storage

Sections of the River Lugg have been dredged and resectioned and as a result the channel is incised with limited floodplain connection. Consequently water passes through the system at a faster rate than may be naturally anticipated, meaning high rainfall events lead to flooding of areas up- and downstream and likely elevated rates of erosion (in combination with a degraded riparian zone). The creation of backwaters and connected wet woodland habitat provide an area of storage for water in high flows, alleviating areas downstream by increasing the lag time of the rainfall event.

Backwaters are areas of standing water that are connected to the river during most flow events. These also act to enhance the habitat and flow diversity in the uniform sections of channel, creating a refuge area for fish and other species. Wet woodland habitat was observed along the River Lugg during fluvial audit 3 upstream of Leominster. These habitats only tend to be connected to the river during high flow events and enable storage of water. The creation of a wet woodland area enhances the riparian zone alongside the river, as well as providing habitat for both aquatic (in areas of standing water and during high flows) and terrestrial ecology.

Flood storage within the key tributary catchments (e.g. the River Arrow) could also provide a direct benefit for the River Lugg, slowing down peak flows reaching the river and the downstream major towns/cities. This could also have a potential beneficial impact on the River Wye, of which the River Lugg is a tributary.

7.4 Summary of Restoration Measures

Watercourses with a high degree of naturalness are governed by dynamic processes which result in a mosaic of characteristic physical biotopes, including a range of substrate types, variations in flow, channel width and depth, in-channel and side-channel sedimentation features (including transiently exposed sediments), bank profiles (including shallow and steep slopes), erosion features (such as cliffs) and both in-channel and bankside (woody and herbaceous) vegetation cover. All of these biotopes, and their characteristic patterns within the river corridor, are important to the full expression of the biological community. A range of physical habitat modifications cause simplification of biotope mosaics, resulting in declines of characteristic biota dependent upon biotopes that have been lost or reduced in extent. River restoration should be based on restoring natural geomorphological processes (including restoration of hydrological continuity between river and floodplain) as far as possible to allow restoration of characteristic and sustainable biotope mosaics, working within the practical constraints of essential flood protection

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for people and the built environment. Low levels of grazing by suitable livestock are important in generating the full expression of riparian biotopes.

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Table 7.1 The potential restoration measures and their likely impacts on river process, morphology and ecology Potential Impact of restoration measure restoration River process Morphology Ecology measure Riparian buffer and Can create areas of Stabilise the river banks. Established Provides habitat shading and provides in- woodland deposition within the supply of woody material within the channel habitat in the form of leaf litter and regeneration channel. channel in the long term, which will woody debris habitat. Beneficial to fisheries help create variation in sediment and and riparian invertebrates in the channel and flow, and develop areas of margins, and to otters in terms of riparian deposition and erosion. habitat provision. Weir removal or Reinstate natural Reinstate natural morphological Provide natural bed and banks. Reinstate modification channel process (will features, removing bed and bank natural pool-riffle sequence, improve vary depending on the reinforcement. connectivity for fish and invertebrates, and reach). reduce migration delays and risk of temperature stress. Land management Reduce diffuse Reduce levels of fine sediment, Reduce levels of fine sediment and nutrients measures pollution, removing encouraging natural bed substrate. entering the watercourse, improving fine sediment from the spawning gravels and egg survival rates, and river system. improving channel habitat. Reduced risk of poor water quality directly affecting fish and invertebrates. Reduced risk of shift to a more nutrient tolerant plant community, including algae. Benefit to ranunculus plant community, which requires clean bed substrate to root securely, with associated increase in resilience to high flow events. Channel cross Improve lateral Reinstate natural morphological Create new habitat within the river channel section connectivity, features and interactions. and on the floodplain. enhancements and encouraging natural removal/breaching processes with of embankments floodplain interaction. Flood storage Encourage natural Provide storage for flood waters and Create new habitat areas, including areas of fluvial processes by new morphological features. Wet slow flow for juvenile fish. Terrestrial ecology providing a storage woodland may also act to trap fine would also benefit from wet woodland habitat. area for water. sediment.

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7.5 Categorisation of Restoration Measures

The restoration measures have been classified into five categories based on the level of restoration needed, each have been assigned a colour code (Table 7.2). The restoration actions are presented in more detail in the accompanying Management Report. These categories are as follows:

1. Significant channel restoration - where the river has been extensively modified by major structures such as weirs, channel straightening and extensive lengths of bank reinforcement*. 2. Assistance with natural channel recovery or measures to improve habitat and flow within the constraints of modified water bodies - where the river has started to recover a natural morphology, or displays the ability to recover, to past channel modifications, but the ability of the river to adjust fully or within a short time scale is considered unlikely without human intervention. There is typically less disturbance to the river in the short term compared to ‘significant channel restoration’. 3. Natural recovery/conserve and protect (no active restoration) - where the river channel is actively recovering a natural morphology from past channel modification. Natural fluvial processes are altering the channel bed and banks and improved habitats are developing. Optimal channel morphology is considered likely to develop without human intervention or some improvements such as riparian zone replenishment could be implemented. Routine maintenance should be practiced within the reach including control of invasive non-native species and coppicing to control phytophthora. 4. Riparian zone management (including tree planting and woody debris installation) - where riparian zone is degraded or where invasive species are growing. Where riparian zone management is recommended, tree planting and reduced grazing pressure are the principal measures intended for implementation. Where such measures are not possible, woody debris installation should be considered provided it does not have a negative impact on recreational pursuits such as canoeing. Riparian management also includes coppicing to control phytophthora.

Figure 7.1 provides an overview of the locations of the four restoration categories for the River Lugg developed as part of the restoration plan. A series of visualisations of river restoration are provided in the accompanying Management Report.

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Table 7.2 Restoration option classification Colour Impacts on geomorphology Category Description Timing code and ecology Significant Red Opportunities for weir removal, weir Commencement of works dependent Improve connectivity between channel improvement, extensive removal of bank on funding available (short to long channel and riparian zone / restoration reinforcement and realignment of flood term). Full recovery, including floodplain. Improves bank banks, major re-meandering or channel established habitats, expected habitat. Improve sediment section restoration. between 10 and 30+ years (medium to dynamics within reach. Improve long term) depending on scale of flow and substrate diversity. works Assisted Orange Removal of minor channel structures or Commencement of works dependent Improve connectivity between natural channel resectioning (localised or short on funding available (short to long channel and riparian zone / channel sections). Removal, et back or term). Full recovery, including floodplain. Improves bank recovery breaching of embankments to create established habitats, expected habitat. flood storage zones and improve between 3 and 15 years (short to floodplain connectivity and installation of medium term). bioengineering measures. Natural Yellow The channel is currently adjusting Already occurring (immediate). Full Allow deposition of coarse recover/conser towards favourable condition and no recovery, including established sediments for spawning and ve and protect specific intervention is required, or some habitats, expected between 3 and 15 juvenile life stages. (no active improvements such as riparian zone years (short to medium term). restoration) replenishment could be implemented.

Riparian Zone Blue Riparian zone measures are proposed Commencement of restoration Reduced fine sediment input Management to improve sediment budget and measure dependent on landowner from surface runoff and (including tree dynamics with the river system, or to agreement, cooperation, funding and increased marginal cover for planting and encourage a more natural temperature potentially legislation (short to long fish. Remove fine sediment from woody debris control and lateral migration rate within term). Full recovery/establishment of surface runoff to prevent siltation installation) the stream. This could be achieved by habitats expected between 3 and 15 of substrates. enhancing buffer strip, tree planting and years (short to medium term). management, and occasional fencing where needed. Riparian zone works may also provide flood relief measures if targeted to strategic locations.

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Figure 7.1a Locations of the restoration categories for the River Lugg

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Figure 7.1b Locations of the restoration categories for the River Lugg

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7.6 Constraints

River restoration is part of an iterative process that needs to consider not only localised processes but also catchment scale processes and constraints. The overall aim is to restore the river habitat as far as practicably possible whilst working with natural process and taking into account localised and catchment wide constraints. Typically restoration is planned with longer timescales in mind, carefully designing and working with landowners to secure incentives and addressing the potential constraints.

Constraints in the Lugg catchment include flow regulation, flood risk, the historic environment, designated sites, protected species and recreational activities. Flow regulation along the Lower Lugg relates primarily to water abstraction. There are a number of known large licenced abstractions as well as smaller scale abstractions for practices such as spray irrigation. These would need to be maintained and not altered or negatively impacted as a result of any restoration works. For the purposes of this project the licensed abstraction is taken as a given pressure.

Current levels of flood protection must not be compromised and any restoration must allow for improvements to current and future flood risk management. There may be opportunities for restoration options to also provide natural flood risk management benefits, for example, and opportunities could be sought for floodplain reconnection which will provide additional flood storage capacity.

Restoration measures would also need to ensure that any receptors in the vicinity of the planned works are not impacted. Sensitive historic features, designated sites (particularly those downstream) and protected species could pose a constraint on desired restoration measures, but could also provide an opportunity for an integrated approach in improving habitats/connectivity on a larger scale.

River restoration would also need to consider existing recreational activities as well as the potential for generating additional recreation activities. The River Lugg is utilised by a number of stakeholders including canoers, fishermen, walkers and local residents. The needs to these stakeholders would need to be considered and where applicable measures incorporated into designs to maintain use and interactions with the River Lugg.

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8 Implementing the Plan

8.1 Stakeholder Involvement

The restoration actions presented in the Management Report are required to achieve favourable condition in the SSSIs of the River Lugg and the River Wye SAC. Therefore, the accompanying Management Report will inform future decision making by the Environment Agency, Natural England and Natural Resources Wales (Statutory Bodies). Implementation of the Management Report (comprising the restoration plans) will require effective and positive engagement with stakeholders.

The views and concerns of a cross section of stakeholders on the draft strategy will be sought. An event will be held for: individual land owners; land managers; farmers; representatives from local communities; relevant public bodies and delivery partners. To facilitate the involvement of land owners and other stakeholders the Statutory Bodies have taken steps to inform the community and other stakeholder groups of this project. This report and the accompanying Management Report are pre-consultation documents and will be updated incorporating comments and suggestions made during the comment process. In particular, the comment period will be used to check facts, hear views on constraints, existing restoration approaches and potential opportunities. The comments and information generated through this will shape the final strategy. Future detailed discussions with land owners about specific river reaches will be an essential part of developing reach specific restoration projects in the coming years.

8.2 Restoration Prioritisation

The Lugg is considered to have a relatively natural morphology – especially in its upper reaches (Units 3 and 4 of the SSSIs). A review of the existing data combined with spot checks/bespoke fluvial audits during January/February 2014 and October 2014 revealed that there are a number of pressures within the Lugg catchment (between Presteigne and the River Wye confluence) that are preventing the river from achieving favourable condition (SSSI/SAC) and good ecological status (WFD). Like most catchments in Britain the riparian zone vegetation could be improved through tree planting and creation of a riparian scrub.

Surface runoff containing fine sediment from tilled fields was noted, with lack of adequate buffer strips in some areas. The extent and severity of livestock poaching was limited although present, and the need to prevent access has been marked where required. Best land use practices should be encouraged catchment-wide to arrive at a minimised top-soil loss to the river with its inherent benefits to both ecology and farming alike, in terms of increased habitat potential and increased efficiency of agricultural productivity.

The restoration potential of each reach surveyed (Table 7.1) together with information derived from the desk study of this report will form the basis of the outline reach-by-reach restoration plans which will be provided in the accompanying River Lugg Restoration Management Report. A clear sequence of restoration actions will need to be established to ensure that these plans are implemented correctly within the Lower Lugg and function effectively.

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8.3 Shaping the Actions

The level of detail to which the restoration options are described in this report reflects a strategic focus. To accurately cost and implement the restoration actions, further work will be required to undertake feasibility studies and then develop outline and detailed designs for each of the restoration actions included in the plans. The degree of feasibility assessment and design work required will depend upon the details of each restoration action and the outcomes of further consultation. An indication of the potential scale of this work is provided in Table 7.2. Both stages of this further work will be undertaken in co-operation with land owners who will play an important role in shaping the detail of future restoration work.

Co-operation and engagement will not end with the implementation of restoration measures. The Environment Agency and Natural England will continue to work proactively with land owners, managers and stakeholders to ensure the long term success and sustainability of the restoration measures. This will include monitoring the restored areas and where necessary, undertaking adaptive management. Management of the river and its surroundings is an ongoing and long term process, with an emphasis on maximising the habitat value of the river environment.

Examples of the types of management that might be necessary include:

 Managing woody material within the channel in line with best practice;  Managing living trees through coppicing or pollarding to maintain healthy trees and managing the supply of woody debris or the degree of shading;  Keeping fences in a good state of repair to exclude farm animals from poaching river banks; and,  Rarely, but occasionally removing blockages, caused by a localised build-up of debris (including wood or rubbish), from the river channel.

8.4 Delivery Mechanisms, Guidance and Sources of Funding

Whole river restoration plans are based on multi-partner working, time horizons suited to the nature and scale of each site’s problems and solutions (typically over 20 to 40 years), a negotiated settlement to any disagreements, and a best endeavours approach to implementation. Funds need to be secured to maintain best endeavours over time, including rolling bids to obvious budgets such as Environment Agency’s Flood and Coastal Risk Management (FCRM) capital works, European Funds, and Environmental Stewardship, but also opportunistic bids to a range of other funding sources including European programmes. Similar work from organisations, including ‘third sector’ partners such as the Rivers Trusts, has a vital part to play.

Delivering the restoration vision will involve working in partnership with a range of individuals and organisations including:

 Angling Associations;  Water companies (Welsh Water (Dŵr Cymru) and Severn Trent Water);  National Farmers Union;  Country Land and Business Association;  Forestry Commission; and,  The Wildlife Trusts.

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Funding may be available from a number of different sources, some of which are listed below; all stakeholder contributions that may help to deliver this plan will be welcomed. The delivery mechanisms, guidance and funding are described in detail in the River Lugg Management Plan and not presented here to avoid repetition.

 Water Framework Directive Improvement Fund;  European Funding;  Environmental Stewardship Schemes;  Countryside Stewardship;  Glastir;  Catchment Sensitive Farming;  Nutrient Management Plan;  Forestry Commission English Woodland Grant Scheme;  Wye and Usk Foundation; and,  Lugg Living Landscape Project.

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