River Dee SSSI

Restoration Vision Report

Final draft for client comment

November 2009

Document control sheet BPP 04 F8

Client: Natural England Project: River Dee SSSI Restoration Vision Job No: B1115530 Document Title: River Dee SSSI Vision Report

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ORIGINAL NAME NAME NAME NAME Elinor Harris Jo Barlow Suzanne Maas Simon Holden DATE SIGNATURE SIGNATURE SIGNATURE SIGNATURE 24/11/09

Document Status – Working draft

REVISION NAME NAME NAME NAME Jo Barlow Suzanne Maas Suzanne Maas Suzanne Maas DATE SIGNATURE SIGNATURE SIGNATURE SIGNATURE 30/11/09

Document Status – Final Draft to Client

REVISION NAME NAME NAME NAME

DATE SIGNATURE SIGNATURE SIGNATURE SIGNATURE

Document Status

REVISION NAME NAME NAME NAME

DATE SIGNATURE SIGNATURE SIGNATURE SIGNATURE

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Jacobs Engineering U.K. Limited

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Contents

1 Introduction 1

1.1 Background 1

1.2 Rationale for Restoration Visions for SSSI Rivers 1

1.3 Aims and Objectives 1

1.4 Method 2

2 Desk Study 3

2.1 Review of Dee catchment 3

2.2 Map-based Review of River Modifications 4

3 Ecological and Geomorphological Site Visits 9

3.1 Site Visit Locations 9

3.2 Summary of Geomorphological Character and Modifications 11

3.3 Summary of Habitat Type / Suitability 12

4 Restoration Vision 14

4.1 Restoration Visions for SSSI Units 14

5 Conclusions and Recommendations 18

5.1 Conclusions and recommendations for SSSI restoration 18

6 References 19

Appendix A - SSSI River Type Summary for River Dee

Appendix B - Field Notes and Photographs

1 Introduction

1.1 Background

Natural England has recently completed a condition assessment for all river SSSIs. Many river SSSIs, or sections of river SSSIs, were found to have been physically modified (often a result of historical activities), which has affected the optimal (natural) functioning of the river system and associated habitats for characteristic wildlife communities. These modifications are recognised as reasons for ‘Unfavourable Condition’ - e.g. inappropriate dredging; inappropriate weirs, dams or other channel structures; silting, and inland flood defence works.

A target has been set to bring 95% of all nationally important wildlife sites in England into ‘Favourable Condition’ by 2010. This target is included within a contract between the Treasury and Department of the Environment, Food and Rural Affairs (Defra) known as a Public Service Agreement (PSA). The aim of this PSA (3) is to deliver a number of performance targets and increased productivity in return for resources allocated to that Department. This allows the Government to link aspects of environmental and conservation work, to improve the status of ecosystems and to minimise the impacts of pollution.

1.2 Rationale for Restoration Visions for SSSI Rivers

For those river SSSIs judged to not be in ‘Favourable Condition’, Natural England has identified actions to remedy this condition together with other organisations, which could be responsible for a number of actions.

Natural England’s SSSI Remedies Programme includes ‘river restoration projects’ as a mechanism for achieving ‘Favourable Condition’. The objectives for ‘Favourable Condition’ in SSSIs designated for river habitat have been set out in Common Standards agreed by the UK conservation agencies. They apply to SAC and SSSI designations and relate to the ability of the river (as a representative of its type) to provide favourable habitat conditions for the characteristic biological community for a natural river type, rather than conditions which might favour a particular species.

To deliver this target, a Restoration Vision for each river SSSI is required to provide a goal to work towards, based upon the unmodified catchment character (natural form and function for that river type (River Dee is classed as Type VI, see Appendix A)). To implement the Vision, a more detailed survey may be required to produce more targeted site specific reach-scale restoration plans to deliver prioritised remediation works.

1.3 Aims and Objectives

The main aim of this project is to understand the potential ecological impacts of river modifications to develop a high-level vision for the restoration of rivers in the River Dee catchment.

The objectives are to:

1. Evaluate key modifications which may have reduced habitat provision and quality; Dee SSSI - Final Draft report 30-11-09 - comp.doc 1

2. Characterise the ecological consequence of these modifications, including which components of the biota have been significantly affected; 3. Provide a high-level long-term vision for the river in its restored state, including a description of the improvements in habitat provision and benefits to flora and fauna; 4. Identify restoration options that would maximise the use of a natural recovery process.

1.4 Method

A desk study was undertaken to identify areas where the river channel is likely to have been modified. The following sources were used to identify potential areas and type of modification:

• Aerial photographs; • Ordnance Survey maps (1:25,000 scale); • Historic maps; and • Geodata (2005) Fluvial Audit report.

The desk-based information was then used to identify potential ecological impacts of the modifications. In doing so, reference was made to the Conservation Objectives for the River Dee set by Natural England. The findings are summarised in Table 2.A.

The desk-based information was used to highlight key areas to carry out field spot- checks for geomorphological and ecological assessment. The site visits focused on:

• Areas with limited modifications and displaying good morphology, which could be used as ‘template’ reaches; • Areas with obvious modifications to assess potential ecological impacts of those modifications; • Areas where modifications were uncertain following the desk study.

Nine ‘spot check’ locations were visited over two consecutive days. Photographs and geomorphological and ecological notes were taken at each spot check.

The findings of the desk study and site visits are summarised in Sections 2 and 3 for each of the three SSSI Units covered by this study (a total of approximately 45km length). These findings were used to identify potential river restoration options and create a high-level, long-term vision for the river in its restored state, for each of the three SSSI Units. The restoration visions are detailed in Section 4.

The ‘spot-check’ nature of site visits undertaken for this preliminary study limits the evaluation to a certain extent. Particular features or modifications could have been missed as it was not a continuous survey. Also some interactions between modifications and impacts such as siltation may not have been identified. If a full field survey assessment is subsequently undertaken to establish site-specific restoration measures, a geomorphological and ecological survey could then be tailored to assess in detail the extent and impact of both physical modifications and sediment supply.

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2 Desk Study

2.1 Review of Dee catchment

2.1.1 Summary of SSSI extent and condition

The River Dee flows across the national boundary between England and Wales. As a consequence of the boundary it is notified as separate SSSIs – the River Dee (England) and the Afon Dyfrdwy – River Dee (Wales). The River Dee (England) SSSI covers an area of 370.5ha and comprises the River Dee between North Shropshire and Chester (except between Overton and Worthenbury which is part of the Welsh SSSI), along with part of its tributary, the River Ceiriog. The source of the River Dee is in Snowdonia.

The reasons for designation of the SSSI are the range of river types (from mesotrophic to eutrophic), the associated habitats of which support the presence of otters, club-tailed dragonfly and migratory fish (Atlantic salmon). There is also a section of meanders designated for its fluvial geomorphology.

The area of interest for fluvial geomorphology comprises a meandering reach of the River Dee between Holt in the North and Worthenbury in the south. These meanders have some of the most spectacular and intricately developed bends seen anywhere in Britain. Most large British rivers have been significantly channelised in their lower reaches. The Dee is exceptional in maintaining an extremely sinuous planform through its lower reaches, in particular into the fluvio-estuarine transition zone. Interestingly, the River Dee is also reputed to be the most regulated river in Europe, with flow controlled by the reservoirs of Tegid, Celyn and Brenig.

The River Dee SSSI has been divided into 3 management Units, starting at Chester progressing upstream:

• Unit 1 – River Dee Cheshire, • Unit 2 – Farndon to Shocklach and • Unit 3 – River Ceiriog Tributary.

Unit 2 has been assessed as being in ‘Favourable Condition’ (for geomorphology), but is thought by Natural England to be unfavourable in terms of ecology. However, Units 1 and 3 have been classified as being in ‘Unfavourable Condition’ with no change/improvement. Within both these Units the salmon population appears to be in long-term decline. This is partly thought to be due to a decline in habitat quality caused by siltation and water pollution arising from agricultural land. Macrophyte survey data indicates that Ranunculus beds within Unit 1 have also declined over the long term. Monitoring results suggest that Unit 3 continues to provide good habitat for otters.

2.2 Summary of Dee River Basin Management Plan Objectives

The (draft) Dee River Basin Management Plan (RBMP) identifies some of the pressures on the catchment and outlines future measures to help achieve the Water Framework Directive objectives (EA, 2009). In summary:

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2.2.1 Upper Dee (Llyn Tegid to confluence with Afon Ceiriog)

• The watercourses are predominantly classified Good or Moderate Ecological Status or Potential (if HMWB). • The main pressures include diffuse pollution (sediments and nutrients) and urban and industrial development (near Wrexham). • There are planned improvements to sewage treatment works, initiatives to produce advice to farmers and actions to address minewater impacts.

2.2.2 Middle Dee (Afon Ceiriog to canalised section below Chester)

• The watercourses are predominately classified Moderate Ecological Potential (Heavily Modified Water Bodies). • Part of the Middle Dee is designated a SSSI for fluvial geomorphology, but there are some constraints to natural form and function. Management (within an overall restoration strategy) is required that would reconnect the floodplain to encourage natural processes. • There is more pressure on biological and ecological quality than the Upper Dee. Diffuse urban and rural pollution is an issue as is point pollution (sewage). There are also some physical modifications to the channel including obstructions to fish migration. • Improvements planned for the Middle Dee include upgrades to sewage treatment works, provision of advice to farmers and enhancement to diatom and fish and phosphate elements (latter likely to be post 2015).

2.3 Map-based Review of River Modifications

There are a wide range of modifications along the River Dee and its tributary, the River Ceiriog, which are displayed on OS maps and aerial photography, and have been mapped in some detail during a Fluvial Audit undertaken by Geodata (2005). Modifications in general have the primary aim of controlling or confining flow within the channel (such as realignments, embankments and weirs), or protection of the banks from erosion (reinforcements), as well as artificial structures crossing the river but with only minor effects (such as road bridges).

The most extensive modifications of the River Dee, downstream of the confluence with the River Ceiriog, are the fragmented embankments along both banks of the river which protect mostly agricultural land and occasional properties. There are also a number of artificial structures including weirs, road and railway bridges and an aqueduct.

There is evidence of realignment along the lower reaches of the river, indicated by the uncharacteristically low channel sinuosity compared to the middle reaches. However, there are generally only small discrete areas of bank that have been formally protected, sometimes associated with the bridge reinforcement. The types of bank protection recorded in the 2005 Fluvial Audit include concrete, laid stone, wood piling and gabions.

In the lower reaches, particularly through Chester, there is a greater extent of bank protection. Through Chester, the right bank is almost continuously reinforced with concrete. In addition, there is a major weir in Chester which impounds the river for a considerable distance upstream (and acts as the normal tidal limit). There are two further minor weirs within the SSSI, both within Unit 3, one on the River Ceiriog and the other on the River Dee.

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The towns of Holt and Farndon and the city of Chester border the river and are located within its natural floodplain. As well as embankments and bank protection associated with protecting these settlements, the presence of urbanised areas reduces the extent of floodplain the river can inundate during a high flow event and also potentially increases the run-off rate from hard surfaces during periods of high rainfall.

The type and extent of the modifications summarised above are provided in greater detail within the restoration visions for each of the three Units. These can be found in Section 4.

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Table 2-A: River channel modifications (desk study) LB Left Bank; RB Right bank

SSSI River Location and NGR Type of modifications Contemporary Map Evidence Historic Map Evidence (c.1880) Unit

3 Afon Ceiriog Bronygarth - Minor road bridge 1:25,000 OS map, aerial photos Side/artificial channel with 4 sluices. SJ 263 375 - SJ 276 370 - Weir Minor road bridge. - Fish hatchery 3 Afon Ceiriog Pont-Faen - Minor road bridge 1:25,000 OS map, aerial photos Present on historic map. Another side SJ 280 370 channel with sluice present. 3 Afon Ceiriog Chirk - Railway crossing and 1:25,000 OS map, aerial photos. Both present. SJ 286 372 aqueduct 3 Afon Ceiriog Chirk - Chirk Bridge 1:25,000 OS map, aerial photos. Chirk Mill immediately downstream of SJ 290 372 Chirk bridge. 3 Afon Ceiriog Chirk Bank - Weir (EA Gauging) (gravel 1:25,000 OS map, aerial photos, pers. Weir present on historic map, A5 road SJ 295 373 - SJ 299 372 relocated from u/s annually) comm., EA. bridge is not. - A5 road bridge 3 Afon Ceiriog Pont-Y-Blew - Minor road bridges 1:25,000 OS map, aerial photos. Very Slight meander present on historic SJ 310 382 - SJ 315 392 slight change to river planform map but not on OS map at SJ 313 388. downstream of meander at SJ 308 379.

3 River Dee Ceiriog / Dee confluence - Possibly straightened 1:25,000 OS map, aerial photos Straight planform. SJ 322 403 - uncharacteristically straight section suggesting possible realignment, signs of river terrace or embankment. 3 River Dee SJ 321 398 - SJ 338 406 - Embankments on left bank GeoData 2005 drawings. Embankment/raised ground at this only Also signs of terraces on right bank on location is marked on historic maps. aerial photos possibly marked by line of trees. 3 River Dee SJ 328 405 - Pipe crossing with pier in 1:25,000 OS map, aerial photos. There is a line marked at this location middle of channel which could represent the pipe. 3 River Dee SJ 341 408 - SJ 346 416 - Small areas of bank protection GeoData 2005 drawings. on LB 3 River Dee SJ 348 414 - Weir with associated concrete 1:25,000 OS map, aerial photos, Weir is not present on historic maps. and gabions on both banks GeoData 2005 drawings. 3 River Dee Erbistock - Various bank protection on LB GeoData 2005 drawings. SJ 355 413 2 River Dee Worthenbury Brook - Embankment typically along GeoData 2005 drawings. SJ 423 494 - SJ 424 504 both bank tops (gap on RB), Dee SSSI - Final Draft report 30-11-09 - comp.doc 6

SSSI River Location and NGR Type of modifications Contemporary Map Evidence Historic Map Evidence (c.1880) Unit

with a small area of bank protection on RB 2 River Dee SJ 424 504 - SJ 422 518 - Embankments including set GeoData 2005 drawings. Meander not indicated on map. back embankments on both Embankments not shown on OS map. banks, small patch of brick/laid (National boundary (on OS map) stone on LB follows river course except at this location. Instead it appears to follow an old meander bend). 2 River Dee SJ 419 526 - SJ 413 532 - Embankments and minor bank GeoData 2005 drawings. reinforcements on LB 2 River Dee Upstream of Holt - Embankment along both bank GeoData 2005 drawings. A534 is not present on historic map. SJ 413 532 - SJ 410 533 tops 1:25,000 OS map, aerial photos. - Road bridge with associated brick/laid stone (probably abutments) 1 River Dee Holt and Farndon - Fragmented embankments on GeoData 2005 drawings Fewer properties within Holt and SJ 410 533 - SJ 403 549 both sides, bank (Embankments and bank protection). Farndon, straight channel present. reinforcements. 1:25,000 OS map, aerial photos show - Urbanised areas either side of uncharacteristically straight sections river through urbanised areas. - Farndon Bridge - Realigned/straightened approx. 1700m d/s of Farndon Bridge. 1 River Dee SJ 397 552 - SJ 398 560 - Embankment on LB GeoData 2005 drawings, - Sluice on left, fish farm (?) 1:25,000 OS map, aerial photos. (several ponds) on right 1 River Dee SJ 398 560 - SJ 403 560 - Single line of scattered houses 1:25,000 OS map, aerial photos. These are not present on historic map. (houses very close to channel) 1 River Dee SJ 401 561 - SJ 403 560 - Set back embankment LB (?) 1:25,000 OS map. 1 River Dee SJ 403 560 - SJ 413 594 - Embankments on alternating GeoData 2005 drawings, banks 1:25,000 OS map. 1 River Dee Pulford Brook - Long embankment on left GeoData 2005 drawings, SJ 409 577 bank also extends upstream 1:25,000 OS map. along Pulford Brook Pulford Brook appears straightened. 1 River Dee Aldford - Realignment and GeoData 2005 drawings, Planform of river is same as existing. SJ 413 594 - SJ 418 608 embankments on both bank 1:25,000 OS map.

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SSSI River Location and NGR Type of modifications Contemporary Map Evidence Historic Map Evidence (c.1880) Unit

tops, some bank protection Realignment/straightening evident (is lake on left an old channel?) 1 River Dee SJ 418 601 - SJ 421 613 - Possible realignment GeoData 2005 drawings, Planform of river is same as existing. - Sluice on RB, historic drainage 1:25,000 OS map, aerial photos. ditch 1 River Dee Crook of Dee - Embankments on alternating GeoData 2005 drawings, SJ 421 613 - SJ 417 616 banks 1:25,000 OS map. 1 River Dee SJ 417 616 - SJ 414 618 - Possible realignment 1:25,000 OS map (low sinuosity). Planform of river is same as existing.

1 River Dee Ecclestone - Handbridge - Possible realignment/ GeoData 2005 drawings, Planform of river is same as existing. SJ 414 618 - SJ 417 651 straightened 1:25,000 OS map (shows straight A55 is not present. - Several different types of bank channel and widening associated with protection impoundment). - A55 bridge - Impoundment 1 River Dee Chester - Realigned GeoData 2005 drawings, Urban areas have expanded, SJ 417 651 - SJ 405 656 - Extensive concrete bank 1:25,000 OS map particularly on left bank, which on protection (N.B. weir is NTL). historic map is fairly small and - Chester Weir (at SJ 407 658) agricultural land far more extensive. - Urban areas 1 River Dee Roodee - Realigned 1:25,000 OS map Planform of river and major bridges are SJ 405 656 - SJ 395 666 - Bank protection (NB. tidal area). same as existing. - Railway and road bridges 1 River Dee Chester Golf Club - Straightened (completely 1:25,000 OS map Sewage works are not present on SJ 395 666 - SJ 385 654 straight section) (n.b. tidal area). historic map. - Sewage Works

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3 Ecological and Geomorphological Site Visits

3.1 Site Visit Locations

The following locations were identified as ‘spot check locations’ and visited on November 3 rd /4 th 2009. The locations (in a sequence from upstream to downstream) are shown numbered on Figure 3A below.

• 1. River Ceiriog – Bronygarth to Pont Fael; • 2. River Ceiriog at Chirk; • 3. River Ceiriog - Pont Y Blew to Dee Confluence; • 4. River Dee upstream of Erbistock; • 5. Dee Meanders (near Ridleywood); • 6. River Dee - Holt to Farndon; • 7. River Dee at Churton and Almere; • 8. River Dee at Aldford; • 9. River Dee at Chester.

Access to the River Dee was also attempted at Eccleston, but limited due to access.

Flow during the surveys was relatively high due to antecedent rainfall.

At each location notes were made on geomorphological character and modifications, along with ecological habitat suitability. These notes are summarised in Section 3.2 and in significantly more detail in Appendix B.

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Figure 3-A: Location of site visits (base map reproduced from Natural England Conservation Objectives for River Dee, 2009)

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3.2 Summary of Geomorphological Character and Modifications

3.2.1 Unit 3 (River Ceiriog)

The River Ceiriog has moderate to high energy with a channel bed comprised predominantly of cobbles/pebbles. Bed substrate was observed to decrease in size downstream, with boulders and cobbles at the upstream extent, and more mobile gravels downstream before the confluence with the River Dee. A variety of flow types were recorded, although riffles and runs were dominant.

The banks of the river were recorded as fairly steep. However the river is generally regarded as ‘stable’ (there was little sign of planform change, large scale erosion or deposition). This is a result of the relatively resistant geology and soil, and a relatively continuous tree-lining along the majority of the River Ceiriog (tree roots tend to bind the soil comprising the banks, reducing erosion). The typical width of the river was 10-12m. Floodplain areas were limited, with only small patches of active floodplain. Flows were of moderate to high velocity but appear to remain mostly within the river banks due to relatively high gradient.

Small pockets of erosion were observed along the River Ceiriog. One site with more active channel dynamics was recorded upstream of Pont y Blew. At this location a mid-channel bar had formed (deposition) and the left river bank was eroding downstream of the bar. Also at this location, undercutting of banks and the formation of lower berms were observed.

The River Dee, downstream of the confluence with the Ceiriog, is wider (approximately 30m at Erbistock), with lower level banks, silty margins and fine gravel ‘beaches’ at the channel margins. At the time of the visit there were a variety of flows present, with glides/pools and run/riffle sequences.

Within this Unit small areas of reinforced banks associated with old mills, properties and minor road bridges were observed. In general, modifications were observed to be very localised having little impact on habitats. Land use throughout the Unit was observed to be predominately agricultural (livestock grazing rather than arable) with small settlements (Chirk being the largest).

3.2.2 Unit 2 (River Dee, Shocklach - Holt)

This section comprises the Dee meanders which were designated as a SSSI Unit for fluvial geomorphology. Some areas of the meanders appeared largely stable, although active erosion was observed including significant bank slumps/collapse. Erosion had exposed sandy banks , having a relatively low level of cohesion (more susceptible to erosion). Silty margins were also observed, although due to relatively high flow the lower ‘benches’ known to be present from previous geomorphological assessments (Gurnell, 1997, Gurnell et al. 1998, Changxing et al. 1999) were not visible. The predominant flow types observed on the site visit were glides and pools, with some faster flow and upwelling on deeper bends.

The River Dee floodplain through Unit 2 is modified by fragmented embankments particularly along the left bank between Shocklach and Holt. Some minor areas of bank protection were observed, including patches of tipped farm debris and bank reinforcement associated with the A534 road bridge.

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The majority of the Unit flows through a rural landscape. Some poaching (i.e. where cattle trample the banks triggering or accelerating erosion) was observed and the banks were largely unfenced.

The presence of modifications, and the effect of grazing on increasing sediment supply to the channel, could be significant in terms of the favourable designation of this Unit.

3.2.3 Unit 1 (River Dee, Holt - Chester)

The width of the River Dee at Holt and Farndon is approximately 20m, increasing to 30-40m at Aldford and up to 50m at Chester Weir. The water depth obscured the bed substrate on the day of surveys. Tree lining of the channel (strengthening bank stability) was less continuous and riparian cover more limited along the lower reaches of the River Dee. An exception was in the Aldford area, where broadleaved woodland bordering the channel and marginal willows and reeds were noted to be present.

Through Queen’s Park (upstream of Chester) the river is connected to a wide expanse of floodplain grazing meadow, known to flood on average around twice a year. The river in this area is used for navigation/boating and boat wash could be creating small areas of erosion along unprotected banks.

Chester Weir creates a major modification to the river hydrology that significantly alters flow patterns and fluvial processes (e.g. sediment transfer) for a significant distance upstream. Flow was observed to be fairly homogeneous, predominately glides. The right bank through Chester has been extensively reinforced.

Downstream of Chester Weir the flow is tidal dominated, and the river was noted to have silty margins.

3.3 Summary of Habitat Type / Suitability

3.3.1 Unit 3 (River Ceiriog)

The coarse bed substrate along the River Ceiriog provides suitable habitat for juvenile salmon. The deeper riffles (c.300mm deep) with cobble/boulder substrate offer ideal parr habitat. Very young salmon (fry) require riffles with a smaller substrate size (predominantly 16-64mm). This ‘nursery habitat’ was not observed during the survey. Exposed tree roots and marginal slacks provide refuge areas for adult and juvenile salmon (and other fish), although these were more limited.

The wooded areas observed at the upstream limit of this Unit potentially provide good lying-up habitat for otters whilst the fish hatchery offers a potential alternative food resource. Habitat suitability for otters continues to a lesser extent downstream, where in places riparian vegetation was noted to be limited to a single line of trees along the bank top. Good otter foraging habitats (i.e. riffles likely to support salmonid fish) were also recorded for this Unit.

On the Ceiriog, near the confluence with the River Dee, a wooded area was recorded, surrounding an island which forms a backwater from the main channel. The diversity of habitats in this area potentially provides suitable habitats for all life stages of salmon. Potential spawning and nursery habitat was recorded downstream of the bridge. Deeper runs/riffles potentially offer good juvenile habitat and pools with overhanging trees offer suitable holding areas for adults.

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The seemingly abundant potential of fish as a food source, combined with a high level of riparian cover and low level of disturbance, suggests this area offers high quality habitat for otters, and could be a suitable breeding site.

The pools observed along the course of the River Dee provide good holding areas for adult salmon, and areas upstream of riffles provide habitat for spawning. Overhanging trees and coarse woody debris at the channel margins give cover for salmon and lying up areas for otters. Silty areas at the margins of the channel are suitable potential habitat for brook lamprey.

3.3.2 Unit 2 (River Dee, Shocklach - Holt)

The silty margins observed provide suitable habitat for brook lamprey, amocoetes and club-tailed dragonfly larvae. The steep, sandy banks offer suitable nesting habitat for sand martin and kingfisher. The predominant flow types of glides/pools provide good holding areas for salmon. Willow scrub along the right bank offers good lying-up habitat for otter, and the dense vegetation offers suitable habitat for club-tailed dragonfly adults.

3.3.3 Unit 1 (River Dee, Holt - Chester)

In Unit 1 the predominant flow types are glides and pools, providing good holding areas for adult salmon. In general, there are fewer trees and more limited riparian cover along these lower reaches of the River Dee. This reduces the amount of cover for salmon and lying-up habitat for otter. An exception to this is at Aldford where broadleaved woodland and willow scrub was observed to be present. At this location many overhanging and partly submerged trees were observed, which provide good fish and otter habitat.

Chester Weir is likely to restrict upstream migration of salmon, especially at low tides. A fish pass and trap are present at this location. There are limited marginal habitats immediately upstream of the weir due to the extensive bank reinforcement. Queens Meadow, which is on the left bank of the river upstream of Chester, could provide good otter foraging, although there is little lying-up cover. Some of the bank slips and silty margins observed could provide good habitat for brook lamprey.

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4 Restoration Vision

4.1 Existing Habitat Suitability

The impacts of modification including bank reinforcement and flow regulation prevent optimal habitat conditions for key species. The table below summarises the effect of modifications in the three SSSI Units. The characteristics are based on the features associated with the Type VI rivers (see Appendix A). The categories are subjective and are based on limited field observations.

Unit 1 Unit 2 Unit 3 Key Impacts Channel realignment/straightening High impact Mod impact Low impact Bank reprofiling/embankments Mod impact Mod impact Low impact Bank reinforcement High impact Low impact Low impact In-channel structures (e.g. weirs); major High impact Mod impact Low impact ponding Flow regulation/abstraction High impact High impact Low impact Siltation Difficult to determine due to high flows

Natural Characteristics Gravel/pebble substrate* None seen None seen Extensive Exposed bedrock/boulders N/A N/A Present Natural ponding Impoundment Present Limited Riffles, pools, glides Glides Glides All Present Exposed unvegetated gravel bars* None seen None seen Present Vegetated gravel bars* None seen None seen None seen Marginal in-channel vegetation Limited Present Limited Vertical cliffs (active erosion) Limited Extensive Limited Stable meanders Limited Present Extensive Riparian vegetation Limited Present Present Exposed tree roots Limited Present Extensive Channel - floodplain connection Present Limited Present *Visibility difficult in lower reaches due to high flows Suitable habitat for SSSI Species Otter Limited Present Extensive Atlantic Salmon (adult) Present Present Present Atlantic Salmon (juvenile) Limited Limited Extensive Atlantic Salmon (spawning) Limited Limited Present Clubtailed Dragonfly Limited Present N/A

Potential Restoration Measures Reduced/modified channel maintenance Mod benefit Mod benefit Low benefit and other operations Removal/lowering of in-channel control High benefit Mod benefit Mod benefit structures (feasibility?) Bank restoration High benefit Mod benefit Low benefit Re-meandering Unfeasible Not required Not required Livestock Management Mod benefit High benefit Low benefit

4.2 Restoration Visions for SSSI Units

Restoration ‘Visions’ for the three SSSI Units are included below. These visions summarise the current state of habitat suitability, geomorphology and modifications, and suggest potential restoration and management actions. Dee SSSI - Final Draft report 30-11-09 - comp.doc 14

Restoration Vision: Unit 1 – River Dee Cheshire

This Unit includes the River Dee between Holt Bridge (SJ 411 534) and Chester (sewage works at SJ 395 666). This section is approximately 22km long, has a low gradient and is tidally influenced. The river flows in a northerly direction past the urban areas of Aldford, Ecclestone and Huntington before flowing through Chester.

Within this Unit the SSSI is classified as being in an unfavourable condition with no change/improvement. The salmon population is thought to be in long-term decline and in part this is considered to be due to a decline in habitat quality caused by siltation and water pollution from agriculture/run off and discharge. Macrophyte survey data indicate that Ranunculus sp. beds have also declined over the long term.

Ecology and Habitat

• Predominant flow types are glides and pools providing good holding areas for salmon. • Fewer trees and limited riparian cover compared to the other Units, which reduces marginal shade for salmon and lying-up habitat for otters. • At Aldford there is broadleaved woodland and willow scrub. There are many overhanging and partly submerged trees at this location providing good juvenile fish habitat and otter foraging habitat. • In Chester the weir is likely to be an obstacle hold up migrating salmon, although there is a fish pass. There are limited marginal habitats upstream of the weir. • Queens Meadows upstream of the weir could provide good otter foraging, although there is little lying up cover. At this location there are some bank slips and silty margins which provide suitable habitat for brook lamprey.

Geomorphology and Modifications Restoration Potential

• Lower sinuosity than middle • At Chester extensive bank reinforcements Wide channel, typical width 30 -40m, tree lined, glide flow reaches which suggests channel severely limit marginal habitats. Use of realignment. pre-planted coir rolls could increase • Fragmented embankments along marginal habitat in places, but are not both sides of the channel. suitable in deep water. • Single line of scattered properties along bank tops (some located • Re-landscaping the right bank through on inside of meander bends). Chester could provide landscape and • Variety of bank protection, ecological benefits. including small discrete patches of wood piling, concrete and laid • Queens Meadows floodplain could stone. potentially be an area for improvement of • A few road bridges and a railway marginal habitat cover (development of bridge, with associated bank marginal reed beds), where a ‘water level protection. management’ approach could increase • Outside of meander bend (right potential fish fry habitats. bank) continuously reinforced with concrete through Chester. • The meander bend upstream of Aldford is The left bank appears to be fairly a good template reach for improving natural. riparian and channel margin habitat throughout this Unit where possible (e.g. Upstream vie w through Chester, reinforced • Chester Weir is a large right bank and Chester Weir modification that significantly Farndon, Aldford and near Crook of Dee). impounds flow.

Dee SSSI - Final Draft report 30-11-09 - comp.doc 15 © Crown Copyright and database right [2009]. Ordnance Survey licence number 100022021.

Management and Restoration Options: Unit 2 – Farndon to Shocklach

This Unit focuses on the River Dee between Shocklach (SJ 423 493) and Holt Bridge (SJ 411 534). This stretch of river is approximately 11km long. The river flows in a northerly direction and has a low gradient.

This section comprises the Dee meanders which were designated as a SSSI Unit for fluvial geomorphology. The SSSI is in favourable condition (for geomorphology) in this Unit but ecology could be improved.

Ecology and Habitat

• The predominant flow types of glides/pools provide good holding areas for salmon. • Silt substrates associated with this Unit are likely to be important for club-tailed dragonfly larvae and brook lamprey larvae. • Steep sandy banks provide good habitat for sand martin and kingfisher nesting. • Willow scrub is potentially good otter habitat and the dense vegetation is suitable for adult club-tailed dragonfly.

Tree lining , including overhanging trees , provides good lying-up areas for otters and shade/cover for salmon

Geomorphology and Modifications Restoration Potential

• ‘Tortuous’ meanders due to erosion of river course through sandy • Riparian vegetation is limited to right bank. glacial lake sediments. Increasing vegetation by fencing out • Lower ‘benches’ in channel not visible due to high flows. grazing livestock and possibly planting • Predominantly agricultural land use. locally sourced willow/alder on left bank • Patches of isolated bank protection. would improve habitat for otter and adult • Left bank is extensively embanked (set-back in places), with limited club-tailed dragonfly. It would also help to riparian cover. reduce erosion of the left bank, reducing • Erosion of embankments on outer bends, some of which now form the sediment input and potential siltation of the upper part of the bank. river bed. • Minor areas of bank protection and A534 road bridge with associated bank reinforcement. • No physical channel restoration would be proposed (or necessary) if natural geomorphological processes are allowed to continue as recommended.

• Landowners could be encouraged not to prevent bank erosion through tipping debris as it is unlikely to be effective, and there is relatively little at risk. Promotion of agri-environmental schemes could be required.

© Crown Copyright and database right [2009]. Ordnance Survey licence Erosion of bank and embankment; steep sandy banks number 100022021. provide suitable habitat for sand martin and kingfisher nesting

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Management and Restoration Options: Unit 3 – River Ceiriog

The section of river in this SSSI Unit is the River Ceiriog, between Bronygarth (SJ 263 375) and its confluence with the River Dee (SJ 317 395), then continuing along the River Dee to Erbistock (SJ 356 412). The total length is approximately 13km. The River Ceiriog has a medium gradient with moderate to high energy flows. The River Dee is a lower gradient river.

The River Ceiriog is classified as unfavourable with no change/improvement. The salmon population is thought to be in long-term decline and in part this is considered to be due to a decline in habitat quality caused by siltation and water pollution from agricultural land. Monitoring suggests that the Unit may be in good condition for otters.

Ecology and Habitat

• Coarse bed substrate provides suitable habitat for salmon and deeper riffles are ideal parr habitat. • Tree cover along the riparian zone is extensive but decreases downstream, although the majority of the Unit is tree-lined. • Exposed tree roots and marginal slacks provide refuge areas for juvenile salmon. Overhanging trees and coarse woody Fine gravel at channel margins with shallow banks and debris at the channel margins provide shade for salmon and tree lining along the River Dee near Erbistock foraging and lying up areas for otters. • On the River Ceiriog, near the confluence with the River Dee, Geomorphology and Modifications an island forms a backwater from the main channel. The deeper pools in this area provide good holding areas for • River modification is limited within this Unit. salmon and overhanging trees provide shade/shelter. Flow energy and gradient are moderate to high • The pools along the River Dee provide good holding areas along the River Ceiriog. for adult salmon, and areas upstream of riffles provide habitat • There are two weirs, one associated with a fish for spawning. hatchery (River Ceiriog) and the other • Sandier areas at the margins of the channel provide suitable associated with a gauging station (River Dee), habitat for lamprey. but with limited impact on flows. • There are a number of road bridges, a railway bridge, an aqueduct and an elevated pipe which all cross the river. At these sites there could be Restoration Potential some bank protection around the structures.

• Fencing in some areas to restrict livestock access to banks would increase extent of riparian vegetation cover (benefiting salmon and otter) and reduce input of silt from trampling and surface runoff.

• Modifications are not prevalent in this Unit. Allowing natural geomorphological processes to take place should ensure the good variety of habitats is maintained.

• An inspection of the impact of weirs on fish passage and morphology could reveal potential actions for removal or modification.

© Crown Copyright and database right [2009]. Ordnance Survey licence number 100022021. Riffles and runs along River Ceiriog, tree lin ed channel Dee SSSI - Final Draft report 30-11-09 - comp.doc 17

5 Conclusions and Recommendations

5.1 Conclusions

The habitats of the River Dee and River Ceiriog are currently modified by some physical structures (bank reinforcements, embankments and other structures), but these are not extensive and are often concentrated in urban areas. The altered hydrology of the River Dee, due to water resources management, is a more significant influence on habitat (e.g. current velocity, water depth, substrate types, temperature and physico-chemical characteristics) through the regulation of flows. The ongoing nature of the extensive flow regulation in the Dee catchment is acknowledged by Natural England to be a constraint on river restoration and the ecology is believed to have adjusted to contemporary conditions (NE, 2009).

The desk study reported here suggests that modifications are relatively limited to points such as bridges and weirs in the River Ceiriog reach (Unit 3) but increase downstream with a series of embankments in the middle reaches of the Dee and increase in extent of hard bank protection in Chester.

An initial ‘spot-check’ field assessment of these modifications was undertaken to advise on the extent to which river habitats and ecology are being influenced by modifications. This suggested that there is suitable habitat present in the catchment, despite modifications, for all of the SSSI interest species (Appendix A). However, some of this habitat may be limited in extent (riparian vegetation) or found only in relatively isolated areas (e.g. optimal salmon spawning habitats).

5.2 Recommendations for next-steps

Large-scale river restoration is unlikely to be required or possible within the constraints of flow regulation. However, there are small-scale modifications which could be investigated for removal and specifically broader actions could be implemented to benefit marginal channel and riparian habitats:

• Vegetation cover and variety could be increased along the channel margins by fencing out livestock in rural areas, or by active planting/intervention in urban areas such as Chester. • Defra/Natural England catchment advisors or Farming and Wildlife Advisory Group (FWAG) representatives could liaise with landowners to identify opportunities for ad-hoc bank protection removal and discuss the merits of allowing the river to adjust naturally. • Agri-environmental schemes and incentives could also be discussed to encourage best farming practice and establish and maintain riparian vegetation through livestock fencing or/and planting along the river corridor. This would link in with proposed initiatives under the Dee River Basin Management Plan (WFD). • More detailed continuous surveys of geomorphology and ecology would inform where bank modifications could be removed and the riparian zone be better established. These surveys would also indicate where river restoration could provide more optimal habitat for key species. If a continuous survey is commissioned, discussions should be held with CCW to consider including the Welsh sections of the SSSI to ensure a ‘whole river’ approach.

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6 References

Changxing, S., Petts, G and Gurnell, A., 1999. Bench development along the regulated, lower River Dee, UK. Earth Surface Processes and Landforms, 24, 2, 135-149.

Countryside Commission for Wales (CCW), 2005. Fluvial Audit of the River Dee. (Geodata Institute).

Environment Agency (2009) Draft Dee River Basin Management Plan.

Gurnell, A.M., 1997. Adjustments in river channel geometry associates with hydraulic discontinuities across the fluvial-tidal transition of a regulated river. Earth Surface Processes and Landforms, 22, 10, 967-985.

Gurnell, A.M., Bickerton, M., Bell, D., Morrissey, I., Petts, G.E. and Sadler, J., 1998. Orphological and ecological change on a meander bend: the role of hydrological processes and the application of GIS.

Mainstone, C., 2007. Rationale for the physical restoration of the SSSI river series in England (Draft V.3 July 2007)

Natural England, 2009. Conservation objectives and definitions of favourable condition for designated features of interest – River Dee – Draft Feb 2009.

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Appendix A - SSSI River Type V/VI

Excerpt from Rationale for the physical restoration of the SSSI river series in England Draft V.3 July 2007 Chris Mainstone (Natural England)

A5. RCT Group B, River Community Types V/VI

Type V - Sandstone, mudstone and hard limestone rivers (southern England)

Rivers in the national SSSI series belonging to the type: Teme (12), Wye (*), Axe (5), Lugg (6),Tweed (4), Ehen (2), Lathkill (2), Dove (7), Frome (2), Moors (1), Blythe (1), Eye (1).

Type VI - Sandstone, mudstone and hard limestone rivers (northern England)

Rivers in the national SSSI series belonging to the type: Eden, (14), Teme (13), Tweed (16), Coquet (3), Cumbrian Derwent (3), Kent (3), Dove (2), Clun (2).

A5.1 Characteristics under conditions of low physical modification

Rivers of these two related types tend to have catchments of mid-altitude, intermediate stream gradients and substrates dominated by gravels and pebbles. Outcropping bedrock and boulders are a relatively common feature of the channel, generating a characteristic mosaic of exposed rock and fast-flowing runnels at low- to-intermediate flows, with some upstream ponding of water behind strata particularly resistant to erosion. A mixture of riffles, pools and glides can be expected under conditions of low physical modification. Exposed shingle bars, occurring in mid-channel and along channel sides and both vegetated and non- vegetated, are common features of these types under conditions of low anthropogenic impact, along with sparsely vegetated sandy margins.

Aquatic mosses (such as Cinclodotus and Brachythecium ) and specialist algal species (such as Lemanea and Hildenbrandia ) are typical of these river types, using bedrock, boulders and large cobbles as substrates. Many invertebrate species, including a number of caddis-fly species and crustaceans ( Gammarus and Asellus ) use the beds of moss for cover and food. The river-sponge ( Ephydatia fluviatilis ) and the river jelly lichen ( Collema dichotomum , a specialist of these Group B river types) also make use of the stable surfaces provided by boulders and bedrock. Birds such as dipper and yellow wagtail use the mosaic of exposed boulders and fast-flowing waters to feed. In such sections, brown trout and salmon tend to be the dominant fish species, along with brook lamprey, stoneloach and bullhead.

In the more geomorphologically stable sections, submerged higher plants such as water-crowfoot ( Ranunculus spp.) and water-milfoil ( Myriophyllum spp .) occur in patches, with their attendant plant-dwelling invertebrate fauna. Dace and chub are more likely to dominate the fish fauna.

Riparian trees are important in providing a source of woody debris, leaf litter, and exposed tree root systems as submerged habitat for fish and invertebrates. As with other river types, the co-occurrence of tree-lined and open sections is likely to be important for a range of invertebrate species.

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In sections with a significant floodplain, active meandering can be expected with the creation of vertical cliffs and point bars. Vertical cliffs are probably naturally most prevalent in these river types, providing the best opportunities for nesting by sand martins, burrowing bees and wasps and other invertebrates of bare soil.

Vegetated shingle is colonised by species such as Oenanthe Crocata and Solanum dulcamara as well as willow (Salix spp.) , with species such as yellow loosestrife (Lysimachia vulgaris ), flowering rush ( Butomus umbellatus ), hemp-agrimony (Eupatorum cannabinum) covering the often sandy and sparsely vegetated banks. Unvegetated, periodically exposed shingle and sand bars give rise to diverse invertebrate assemblages of high conservation value. Birds such as little ringed plover and common tern use the exposed shingle islands for breeding.

A5.2 Key physical impacts

Whilst channel realignment/straightening and reprofiling have been undertaken within these river types, it is not as frequent as in lowland river types. Where it occurs there has been loss of flow and substrate diversity and variation in water depth (including loss of vegetated and unvegetated shingle), affecting a range of characteristic species mentioned above. Diversity in current velocities and substrate type is key to maintaining a diverse biological community – many species tend to occupy a relatively narrow range of conditions, and search for those conditions within the river in the face of widely fluctuating flow conditions through time - regularising the cross-sectional profile greatly reduces the chances of finding suitable refugia under different flow conditions. The point is probably best made by net-spinning caddis-fly larvae, whose prey-catching nets only operate within a narrow velocity range, but the same principle is true for many invertebrate and fish species in terms of finding conditions to hold station within the river and feed.

Bank reinforcement and stabilisation is more commonplace. When undertaken with stone gabions and similar materials, marginal and bankside flora and fauna is lost. Such stabilisation also prevents active migration of the channel and the ability of the river to create new characteristic habitat features.

In-channel structures are relatively common, originally for a range of uses including water-mill off-takes, abstractions, bed stabilisation, fisheries and occasionally navigation. These impound water to an extent dependent on channel gradient and height of structure, increasing silt deposition and obscuring habitat diversity at low- intermediate flows. This can result in increased siltation and the flooding of habitat- rich mosaics of exposed shingle, boulders and bedrock interspersed with fast- flowing runnels and riffles at low-intermediate flows, reducing habitat provision for species characteristic of these features. The movement of species within the river can also be impeded by such structures – whilst there have been increasing moves to alleviate access problems for salmonids by installing passes, this does not resolve access issues for a range of other species requiring free movement in the channel (particularly fish species with lower swimming speeds and invertebrates with no aerial life stages).

A5.3 Key restoration measures

• Reduced/modified channel maintenance and other operations, such as removal of gravel shoals and large woody debris, to promote natural recovery of form and function.

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• Removal/lowering of in-channel control structures , to re-establish riffle and runnel habitat, restore characteristic water depths and currently velocities, reduce siltation and allow free movement of fauna.

• Sensitive restoration of banks, using soft engineering including strategic tree- planting and, where possible, facilitating dynamic channel processes within the floodplain to restore riparian wetland flora and fauna.

• Remeandering or meander reconnection to restore habitat length/area and improve flow, substrate and depth diversity, thereby providing improved habitat conditions for a wide range of characteristic fauna and flora.

• Livestock management to stabilise banks and reduce siltation and channel- widening. Preferably through reducing stock densities or if not possible through fencing set-back from the channel to allow some channel movement and occasional grazing/cutting of vegetation as appropriate.

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Appendix B - Field Notes and Photographs

SSSI Unit 1

Area/Reach Field Notes River Dee, Holt Castle (SSSI Unit 1) Habitat Modifications - Possible right bank resectioning (high and at a 45 degree angle, no trees present). - Bank trampling (cattle)

Habitat Features - Glide (smooth/rippled flow). - Substrate not visible.

Species Suitability - Some holding areas (deeper glides/pools). - Overhead cover from willows on left bank. - Right bank: trees scarce. - Otter: limited lying-up cover on right bank.

Additional Notes - Fencing along right bank would help increase riparian vegetation (thus cover for otter). - River c. 20m wide with 2-3m high banks.

River Dee, Farndon Bridge (Unit 1) Habitat Modifications - Straightened. - Bridge with “in channel” piers. - Bank poaching on left bank.

Habitat Features - Deep glide (smooth/rippled flow). - Substrate not visible. - Right bank: semi-continuous willows. - Left bank: no trees, very sparse cover. - Slight erosion.

Species Suitability - Salmon holding areas: around bridge piers and deeper pools. - Limited otter lying-up habitat.

Additional Notes - c.20-30 m wide - Tree-lined further downstream.

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Area/Reach Field Notes River Dee, Churton and Almere (Unit 1) Habitat Modifications - Straightened. - Embanked on left. - Jetties/landing stages on left. Habitat Features - Deep glide (smooth/rippled flow). - Substrate not visible Species Suitability - Limited riparian vegetation cover (few overhanging trees). - Broadleaved plantation on right bank with drainage ditch. Left bank: caravan park. - Salmon: holding areas in deeper pools. Additional Notes

- River c.20m wide with 2-3m high banks. - Potential to enhance habitats in woodland with ponds. River Dee, Alford (upstream) (Unit 1) Habitat Modifications - None obvious, potential embankment LB.

Habitat Features - Glide flow, marginal deadwaters present. - Good marginal habitats (reeds/willows). - Fallen trees and woody debris in river.

Species Suitability - Left bank: Extensive riparian trees / scrub. - Right bank: Broadleaved woodland and arable - good otter lying-up habitat. - Salmon: holding areas in deep pools. - Lush/dense vegetation is potential habitat for club-tailed dragonfly. - In-river trees – good juvenile fish habitat: good otter foraging habitat.

Additional Notes

- River increasing width with large pool on outer meander bend. - High flow so substrates not visible.

River Dee, Alford (downstream) (Unit 1) Habitat Modifications - Embanked: both banks in places. - Straight. - Single tree line. - Small lengths of bank protection/reprofiling near Iron Bridge.

Habitat Features - Deep Glide (smooth flow). - Quite homogenous.

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Area/Reach Field Notes

Species Suitability - None specific, potential adult salmon holding/transition areas.

Additional Notes

- River increasing width c.30m wide. - Very low gradient.

River Dee, Chester (Unit 1) Habitat Modifications - Weir. - Cascade fish pass. - Walled/reinforced banks. - Boat moorings/jetties. - Bridges. Habitat Features - Glide and slack at weir. - Ponding extends upstream above weir. - Chaotic flow/scour pool below weir. - Substrate not visible. - Marginal habitat limited by bank protection.

Species Suitability - Salmon likely to hold up below weir.

- Good otter foraging habitat, but little lying- up cover (better LB upstream of weir; willow scrub).

- Queens Meadow upstream may provide good otter foraging (amphibians and fish in ditches). Some bank slips/silty margins (brook lamprey amocoete habitat).

Additional Notes - Downstream of weir: tidal, silty margins.

- Upstream of weir: LB has 2m wide strip of vegetation and footpath. Right bank: concrete/boats. Limited marginal habitats due to reinforcements. Could increase marginal habitats with areas of reed planting (coir rolls).

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SSSI Unit 2

Area/Reach Field Notes River Dee, Dee Meanders (SSSI Unit 2) Habitat Modifications - Embanked left bank (c.1 m) – set-back in places on tight meander bends. - Tipped farm debris bank revetments.

Habitat Features - Glides/pools, some faster flow. - Marginal slacks where bank slumps present. - Right bank more stable and vegetated, left bank eroding in places (sandy banks).

Species Suitability - Otter: good foraging. - Continuous willow scrub on right bank offers good lying-up cover. - Dense vegetation ideal for club-tailed dragonfly. - Salmon: good holding pools present. - Silty margins suitable for brook lamprey. - Exposed sandy banks suitable for sand

martin / kingfisher nesting.

Additional Notes - Extensive bank slumps/erosion. - Improved grassland on both banks. - Banks accessible to cattle/sheep grazing and poached/trampled in places.

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SSSI Unit 3

Area/Reach Field Notes River Ceiriog, Bronygarth – Pont Fael Habitat Modifications (SSSI Unit 3) - Fish hatchery. - Reinforced bank (cobble/boulder - old). - Short section of embankment on right. - Single tree line. - Small road bridge. Habitat Features - Riffle/run, high energy. - Cobble/pebble substrate. - Exposed/underwater tree roots. - Small marginal slacks. - Steeper banks downstream. Species Suitability - Salmon: some parr habitat on deeper riffles. - Limited refuge areas (few small slacks). - Otter: good foraging habitat (fish ponds adjacent). Spraint noted on boulder near Pont Fael. - Woodland on right bank offers good lying- up habitat. Additional Notes - Road adjacent to left bank. - Small STW on right bank. - Narrow footpath. - Steep wooded valley (8-10m wide channel). - Japanese knotweed on left bank. River Ceiriog, Chirk (Unit 3) Habitat Modifications - Bridge and viaduct. - Old mill and adjacent properties – some reinforcement. - May be historical straightening?

Habitat Features - Moderate-high energy. - Tree-lined. Some woody debris. - Cobble substrate, occasional boulders. - Downstream: more run flow type.

Species Suitability - Salmon: parr habitat on deeper riffles. - Otter: good foraging. - Limited lying-up cover (riparian vegetation only 1-2 m wide).

Additional Notes - River deeper/narrower than upstream. - Adjacent overground sewage pipeline had been discharging: reported to EA. (EA confirm they have attended and instructed Welsh Water to repair).

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Area/Reach Field Notes River Ceiriog, Pont y Blew (Unit 3) Habitat Modifications - Road nearby – no obvious modification. - Minor road bridge – small areas of reinforcement.

Habitat Features - Varied riffle/run/rapid flow. - Boulder, cobble, pebble, sand substrates. - Eroding bank and mid-channel bar. - Undercut banks and lower berms. - Woody debris.

Species Suitability - Otter: good foraging – footprints under bridge. - Riparian vegetation limited to

single tree line both banks (some exposed roots). - Varied flow, bars and undercut banks create suitable general fish habitat.

Additional Notes - Adjacent land use: improved grassland, gardens, road. - More diverse and wider channel upstream where active geomorphological processes. - Deeper, narrower, faster flow along road. - Small areas of bedrock in RB.

River Ceiriog, Tenement (near Dee Habitat Modifications confluence) (Unit 3) - Bridge and minor reinforcement.

Habitat Features - Mid-channel island creating side channel/backwater. - Wooded, pools, gravel bar. - Gravel pebble/cobble. - Riffles downstream. - Some bedrock.

Species Suitability - Salmon: spawning habitat d/s of bridge (upstream of riffles). - Fry/parr habitat on riffles.

- Holding areas in deeper pools/glides. - Diverse range of habitats for all stages in close proximity. - Otter: good lying-up (island) and foraging.

Additional Notes - Slight cattle poaching on left bank downstream.

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Area/Reach Field Notes River Dee, upstream of Erbistock (Unit Habitat Modifications 3) - None visible.

Habitat Features - Lower level shallow graded banks. - Silty margins with fine gravel ‘beaches’. - Some woody debris. - Glides, riffles/runs, slower margins. - Right bank: mixed woodland/valley side. - Left bank: single tree line/improved grassland.

Species Suitability - Salmon: good holding areas in deeper pools. - Overhanging trees provide cover. - Possibly spawning habitat. - Fry/parr on riffles. - Otter: good lying-up in woodland and good foraging.

Additional Notes - Old river terrace bank line? - Cattle not fenced out. - River c. 30 m wide

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