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CONTENTS

1. Executive Summary 1

Scope and Method 1

Conclusions 2

Recommendations 3

2. The Background to This Study 6

The Key Issues 6

The Policy and Planning Background 7

Previous Technical Studies which led to this Report 8

The Scope of this Study 9

3. The Main Reasons for Considering Alternatives 12

Coastal Change 12

Sustainability 12

4. The Methodology for This Study 16

Introductory Comments 16

Identifying Alternative Patterns of Supply 16

Selecting and Assessing Representative Sources and Sites 17

Comparing the Relative Sustainability of Alternative Patterns of Supply 19

5. The Current Pattern of Supply and Demand 20

Sand Dredged from the Bristol Channel 20

Aggregate Quarried within South East Wales 23

Aggregate Imported from outside South East Wales 24

Secondary and Recycled Materials 24

Demand for Aggregate in South East Wales 26

Summary of the Current Pattern of Supply and Demand 27

6. Potential Alternative Patterns of Supply and Demand 32

Alternative Sources of Aggregate not Currently Exploited 32

Three Potential Alternative Patterns of Supply 38

The Differences between the Current and Alternative Patterns of Supply 46

7. The Selection and Assessment of Representative Sites 48

Choosing a Set of Representative Sites 48

Assessing the Chosen Sites 50

How the Case Studies Contribute to the Patterns of Supply 51

8. The Comparative Sustainability of Alternative Patterns of Supply 54

Description of the Sustainability Assessment Process 54

Pattern of Supply No. 2 Compared to the Current Pattern (No. 1) 54

Pattern of Supply No. 3 Compared to the Current Pattern (No. 1) 56

Pattern of Supply No. 4 Compared to the Current Pattern (No. 1) 58

Conclusions from the Sustainability Assessment Process 61

9. Discussion, Conclusions and Recommendations 64

Discussion 64

Conclusions 66

Recommendations 67

Appendix 1 Research Specification and Steering Group

Appendix 2 Supply Option Fact Sheets

Appendix 3 Site Assessment Check List

Appendix 4 Sustainability Assessment Model

Appendix 5 Coastal Change Issues

Appendix 6 Energy Issues

Appendix 7 Noise Issues

Appendix 8 Traffic Issues

Appendix 9 12 Case Studies

Appendix 10 Sustainability Assessment, Patterns of Supply No. 2 vs No. 1

Appendix 11 Sustainability Assessment, Patterns of Supply No. 3 vs No. 1

Appendix 12 Sustainability Assessment, Patterns of Supply No. 4 vs No. 1

1. Executive Summary

Scope and Method

1.1 This report was commissioned in May 2001 by the National Assembly for Wales (the Assembly)[1]. The report is required as an aid to policy making, and in particular to assist in the difficult choice between continuing to dredge sand from the Bristol Channel or starting to quarry sand and gravel from potential land-based resources.

1.2 It addresses the uncertainties that surround dredging, and specifically the question of whether (and how) dredging sand from offshore sandbanks affects the beaches of South East Wales. Drawing on the findings of a more detailed, new interpretative report by Pethick and Thompson (2002), produced as part of this study, it concludes that, while no significant impacts on the coastline have yet been detected, some dredging, in particular from Nash Bank, may in future have effects on nearby beaches and the wider sediment environment. It therefore recommends that dredging from Nash Bank should be phased out over a period of 5 to 10 years.

1.3 Because of the high quality of the sand which is dredged from the Bristol Channel, replacing it from other sources will be neither easy nor cost-free. The report builds on earlier work undertaken by Symonds to identify potential land-based sand and gravel resources, and compares the overall sustainability (environmental, social and economic) impacts of switching part of the pattern of aggregate supply away from dredging to these and other alternative sources.

1.4 It does this by considering a range of policy scenarios, and the ways in which aggregates suppliers and users might be expected to respond to each one. All practical potential sources of primary, secondary and recycled aggregate are considered.

1.5 The option of stopping current dredging from near to the shore without licensing alternative sources of either dredged or quarried aggregate is assessed as part of this process, but that option is not preferred. The penalties are considered to outweigh the benefits. In particular, the impact of removing so much high quality sand from the market without making alternative provision is felt likely to generate clear and damaging social and economic impacts which do not adequately compensate for the environmental gains, particularly when compared with the alternative approaches. Utilisation of secondary materials (such as china clay sand and crushed rock sand) would be maximised, but at the cost of considerably greater energy consumption (and therefore increased emissions of greenhouse gases). The use of imported materials would also result in the export of some environmental impacts.

1.6 A less drastic approach, of withdrawing all nearshore dredging licences and replacing them with matching licences from further offshore, is also considered. This has the advantage that the disruption to the aggregate market would be reduced (especially if phased in over a period of time). The environmental gains would also be fewer (though not insignificant), and they would be won at the cost of some additional energy consumption.

1.7 An alternative approach, which would also require phasing-in over a period of 5 to 10 years, is also considered. This would involve shifting dredging further offshore, but reducing the overall tonnage that is taken. This would be accompanied by limited exploitation of land-based sand and gravel within South East Wales. It is the timescale for proving individual resources and gaining planning consent for their extraction that would require a considerable phase-in period.

1.8 These various approaches (which are intended to be instructive examples rather than recommended scenarios) are investigated by assessing a broad range of impacts on a balanced group of generally representative sites. Some of these sites are real (i.e. current activities at actual locations), while others are theoretical (e.g. locations where potential land-based resources might be exploited in future).

1.9 The selection of potential sources of supply, and the sites chosen to represent each option, were guided by a project Steering Group[2], whose help and guidance are gratefully acknowledged. Industry members of the Steering Group were actively involved in hosting many of the site visits which were central to the assessment procedure.

1.10 The report reaches the following conclusions:

Conclusions

(i) The policy prescriptions within 'Marine Aggregate Dredging Policy, South Wales' (MADP) are generally prudent, even though the evidence contained in this study points towards a slightly different interpretation of some of the facts compared to that which has obtained before.

(ii) There is evidence of sediment transport links between offshore sandbanks within some parts of the Bristol Channel and the beaches of South East Wales. The links are generally weak, however, and do not imply that dredging will inevitably have impacts on the beaches. The exception is Nash Bank where it is clear that dredging cannot continue indefinitely without eventually giving rise to localised impacts on the adjoining coast. No such impacts have yet been detected, and none are anticipated in the short to medium term, but it would be prudent to phase out the current operations here over the next 5 to 10 years.

(iii) The cases of Nash and Helwick Banks are not directly comparable. Of the two, Nash Bank is far less resilient, because of its location in an area of very high rates of potential sediment transport, and relatively small rates of natural replenishment. Helwick Bank, by comparison, is located within an area of much greater sediment availability, where changes can be buffered by the input of sediment from Carmarthen Bay, without adverse effects on the beaches.

(iv) Over the last decade, Nash Bank has been losing volume at a rate that is higher than can be accounted for by dredging alone, and at current levels of shrinkage could be eliminated altogether within a period of 90 to 215 years. Long before that point it would cease to function as an effective breakwater, and impacts would then be felt on the adjacent shoreline. Alternatives to Nash, as an important source of high quality fine aggregate, therefore do need to be found.

(v) Most of the potential alternatives have very real practical and environmental costs attached to them. Secondary materials like china clay sand and crushed rock sand significantly increase the demand for water and cement in concrete (thereby increasing fossil fuel consumption and emissions of greenhouse gases), and recycled materials generally offer no effective substitute for sand (as opposed to coarse aggregate).

(vi) Good quality land-won sand and gravel deposits offer far greater potential in all of these respects, but also have inevitable impacts on landscape, ecology and the water environment (in particular). These, however, could largely be mitigated, through a combination of careful location and implementation of best working practices.

(vii) Irrespective of environmental considerations, there is no real chance that all of the marine-dredged sand currently landed in South East Wales could be replaced, (even drawing on all realistic alternative sources of supply), without raising the cost and reducing the quality of construction. This would have definite adverse economic consequences for the region, and would not be justified on sustainability grounds. It would also result in environmental impacts being exported.

(viii) Subject to detailed technical assessments of individual prospects being carried out to prove their quality, it should, however, be possible to replace a proportion of the marine-dredged sand by land-won alternatives. Providing that the associated environmental impacts were adequately mitigated, a partial substitution of marine sand with land-won alternatives would provide a more sustainable pattern of supply than that which exists as present.

(ix) Overall, however, this study has indicated that the clearest increase in sustainability would be achieved by a gradual shift of dredging operations from inshore areas (particularly Nash Bank) to other areas further offshore and/or further west. This conclusion is subject to the findings of ongoing and future site-specific environmental assessments at the alternative dredging sites. It would be imprudent, therefore, to rule out the future need for land based sand and gravel resources.

(x) There is a strong economic case for avoiding precipitate change. Any of the alternative policy scenarios that have been considered could be phased in over a transition period, and clear policy statements of intent, tied to a clear timetable, will encourage more efficient and less disruptive market changes.

Recommendations

1.11 The recommendations that flow from the above conclusions are as follows.

(i) Consideration should be given to amending MADP to steer dredging further west along the Bristol Channel and, more specifically, to phase out dredging on Nash Bank over a period of 5 to 10 years. This could be achieved by giving notice that, within a minimum of 5 and a maximum of 10 years, sediment cell CBC1 (which includes Nash Bank) will be re-classified as a Policy 3 area; and that (more immediately) sediment cell IBC2 (which includes Culver Sands) will be re-classified as a Policy 2 area. Further independent research on the geomorphology and sediment dynamics of Culver Bank (not carried out in the present study) might demonstrate that the latter suggestion is unnecessary, but in the absence of such work, a precautionary approach is warranted.

(ii) Other things being equal, and subject to appropriate consideration of more detailed and ongoing technical studies, continued dredging on Helwick bank and new dredging proposals for the Nobel Banks area should be viewed favourably unless and until new evidence is found of adverse environmental impacts that can reasonably be linked to these operations.

(iii) Until such time as it is modified in the light of unequivocal new evidence, the conceptual model developed for this study by Pethick & Thompson (2002) should be used by the Assembly as a context for the evaluation of future dredging applications and for establishing monitoring requirements to be attached to future licenses. These requirements should include full, three-dimensional analysis of bathymetric changes on both licensed areas and adjoining beaches / sand bodies.

(iv) As noted in 'Mineral Planning Policy Wales' (MPPW) and stated clearly in the draft 'Aggregates Technical Advice Note' (Aggregates TAN), Mineral Planning Authorities (MPAs) should, as a matter or urgency, safeguard significant areas of potential land-based sand and gravel resources (as identified in the earlier Symonds report) until such time as these are either exploited or proved by detailed investigations to be technically unsuitable.

(v) In anticipation of the need for at least some land-won sand and gravel in future years, the Aggregates TAN should provide mineral operators with a positive signal that well-founded applications for extraction within appropriate (generally unconstrained) locations will be given favourable consideration. This could take the form of ‘Provisional Preferred Areas’ as outlined in the earlier Symonds report on land-based extraction.

(vi) The Assembly and the South Wales Regional Aggregate Working Party should establish a mechanism for keeping future supply options under review. As well as monitoring the effects of marine dredging, it should monitor the progress of technical investigations of potential land-based and secondary aggregate resources, to determine the extent to which these can be relied upon, if and when required. Depending on the findings of such reviews, future policy options may need to be revised.

(vii) To the extent that specific applications can be identified for the use of secondary aggregates such as crushed rock sand and china clay sand in place of primary aggregates, without giving rise to greater environmental impacts overall, the Assembly and Local Planning Authorities should look favourably on any proposals to develop facilities for the import of such materials into South East Wales by sea or rail.

(viii) The South Wales Regional Aggregate Working Party and/or individual MPAs should carry out at least preliminary desk studies to seek to identify any significant stores of foundry sand in South East Wales in order to establish whether such a material offers a realistic alternative to primary aggregate.

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2. The Background to This Study

The Key Issues

2.1 Aggregates are crucial to society, contributing essential components to housing, commerce, industry, health and leisure facilities, the transport infrastructure and many other facets of modern life. This Study has been prompted by three main considerations central to the supply of aggregates to South East Wales, namely:

(i) the continuing uncertainty that surrounds the long-term effects of dredging for sand in the Bristol Channel, on which South East Wales is highly dependent;

(ii) a desire to achieve reasonable long-term security of supply as far as aggregate in South East Wales is concerned, even if that means considering the exploitation of land-based sources; and

(iii) the importance which the Welsh Assembly Government (the Assembly) places on sustainability right across the spectrum of policy issues.

2.2 For several years South East Wales has relied heavily on the Bristol Channel for its sand, and more heavily on dredged sand than any other part of the UK. Many millions of tonnes of material have been removed, predominantly from sand banks relatively close to the shore. Over recent years local residents and interest groups have become increasingly concerned that changes which they have observed along the shoreline, affecting both beaches and cliffs, might be linked in some way to this dredging activity. This concern has created pressure on the Assembly to review its historic policy of supporting the granting of further licences to dredge. Most of the licences concerned are actually issued by the Crown Estate, which owns the sea bed below the low tide mark. Crown Estate decisions take into account of the Government View, which in this case is the view of the Assembly.

2.3 Set against this pressure to stop dredging is the fact that long-term reliance on marine sand has made it possible for each individual Mineral Planning Authority (MPA) in South East Wales to adopt what is essentially a presumption against land-based sand and gravel extraction. No active sand and gravel pits exist within the region and no policies are currently in place for the safeguarding of potential resources. From the standpoint of the individual MPA this could be justified, because:

(i) quarrying creates some adverse impacts on the surrounding population and environment, which are relatively well understood; and

(ii) the impacts associated with marine dredging had been adjudged (by others) to be acceptable.

2.4 A peremptory policy shift away from dredging and towards favouring land-based extraction would almost inevitably cause disruption in the market for sand over the short term, while applications to quarry sand and gravel went through the planning system. There are alternative sources of sand-like materials (notably crushed rock sand), but these are primarily suited to lower grade uses, and they are neither unlimited nor free of adverse impacts of their own.

2.5 The Assembly has a general objective of seeking sustainable solutions to policy dilemmas. It therefore seeks to promote a sustainable balance of supply sources for aggregate. It has to do this against a background of considerable uncertainty about what actually happens on the sea bed both with and without the influence of dredging, particularly as regards the long-term movement of sand and other sediments. This means that it is not self evident that accepting the known adverse impacts associated with land-based extraction in place of possible gains from stopping dredging constitutes a good bargain.

2.6 After all, the changes which are affecting the beaches and cliffs of South East Wales might simply be part of a very slow long-term process, or they might be due to rising sea levels and increased storm activity associated with global warming, or a combination of all of these.

2.7 In view of its complexity, and its importance, the issue of coastal change is introduced in Chapter 3 (and dealt with in depth in Appendix 5). Chapter 3 also provides a short overview of how this Study will deal with the complex question of sustainability.

2.8 Before that, a brief review of the policy background is provided, along with other essential background to understanding the methodology, which in turn is outlined in Chapter 4.

The Policy and Planning Background

2.9 The policy and planning background to this Study can be found in a range of documents of national, regional, local and site-specific relevance. These are briefly identified below.

2.10 At a national level, the Assembly issued 'Mineral Planning Policy Wales' (MPPW) in December 2000. This encourages each MPA in Wales to make provision for future land-based sand and gravel extraction within the areas for which they are responsible. Even if resources are not earmarked for development, MPPW encourages MPAs to safeguard known blocks of resources, so that future decisions to exploit them are not ruled out by the land having been 'sterilised' by built development.

2.11 In February 2002 the Assembly took matters a step further by issuing a Consultation Draft Minerals Technical Advice Note (Wales) covering aggregates (the Aggregates TAN). This document sets out detailed advice to MPAs and the aggregates industry on the delivery of the policies established in MPPW. When issued in its final form, the TAN will supersede Minerals Planning Guidance Note 6, which previously applied to both Wales and England.

2.12 At a regional level the Assembly initiated a consultation process by issuing a document entitled 'Marine Aggregate Dredging Policy, South Wales' in May 2001. The consultation period ended in July 2001, and responses are currently being considered. MADP, as the document is widely known, assigns one of four policy positions to all areas of the Bristol Channel in which the Assembly has an interest. This has been done to provide potential applicants for licences to dredge sand and gravel with prior guidance on the approach which the Assembly is likely to take.

2.13 These four policy positions are as follows:

(i) Policy 1: the Assembly will look favourably on dredging for marine aggregates in sediment environments where few constraints have been identified (i.e. a positive Government View is likely);

(ii) Policy 2: the Assembly will adopt a precautionary approach to policy until research and/or monitoring can reduce uncertainty of the actual or potential effects of marine dredging to acceptable levels (i.e. use dredging conditions to limit duration and tonnage of licence, and review at end of 5-year interim strategy period);

(iii) Policy 3: the Assembly will not look favourably on dredging for marine aggregates in these sediment environments due to the significance of constraints identified (i.e. a negative Government View is likely);

(iv) Policy 4: the Assembly will safeguard marine aggregate resources in these sediment environments from sterilisation by seabed development and other activities at sea for dredging in the future.

2.14 There are 13 MPAs whose areas of responsibility lie wholly within the study area (which is referred to throughout this report as South East Wales). They are (in alphabetical order):