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Why an Issues Report ?

One of the first stages in the process of managing an estuary is to identify those issues on the estuary which cause concern, conflict or hardship. A process to gather that information has begun, and one important result is this document. The aims of this document are to encourage debate and to ask you for your views on the issues which face the Severn Estuary.

This report is not a statutory management plan for the Severn Estuary but one of the key steps in the process which should be complete by around the year 2000. The process follows Government guidance on how best to achieve consensus and co-ordination in estuary management. This should then lead to actions to protect and improve the estuary and the lives of those who live nearby.

Who has compiled this Report ?

The Severn Estuary Strategy and the Environment Agency have shared resources to compile the report and have been helped by many others including all those people who contributed to the public meetings. We are grateful for their assistance. A list of the main contributors is in chapter 1.

How should I read it ?

PART ONE will introduce you to the document. It provides an introduction to the estuary and a short explanation of the Severn Estuary Strategy and the Environment Agency. It explains the process of estuary management and how this document contributes to that. Chapter 2 gives an overview of the estuary with a brief review of the economy, organisational structure and the environment

PART TWO is arranged in chapters which correspond to the main topics of interest and concern. Each chapter has four main parts:

o. Who does what, which indicate what the main organisations do in relation to that topic;

o. Stated Government Aims, which quotes the aims from the Department of the Environment's Policy Guidelines for the Coast 1995;

o. Background, which describes that topic and provides a general background for the issues;

o. Issues, which describe the issues.

The complex nature of the estuary and the range of issues which have been identified means that there is an 'overlap' of concerns in certain chapters. There is a reference to these at the beginning of each set of issues.

After each issue, there is an indication of 'what is happening', and in some cases, 'some suggestions' have been put forward by contributors. The suggestions are there to stimulate further thought and discussion on the way forward and are not commitments to action. The order of the issues does not imply importance - we want you to tell us which is/are important to you.

Key issues will be dealt with by the working groups which will form part of the Strategy partnership. Some issues and concerns may not have ready solutions, but the fact that they are noted in this report, and identified by the Severn Estuary Strategy, may enable a way forward to be found by those who have the power to deal with them.

Why should I read this report ?

This document reflects the issues as they are perceived at present. This may not be a true representation of the activities on the estuary, or their impact. If this is the case, then it is an indication that further work is needed so that all those concerned can gain a true understanding of how the estuary is used and managed.

This Joint Issues Report will give you an overview of the concerns of those who have contributed thus far. We need to know if you agree with these views. If you have any further comments to make on these issues, it is important to make them known, before the Strategy moves forward to the next phase.

How can I make my views known ?

The BACK COVER holds a quick questionnaire. Please complete this questionnaire and return it in the FREEPOST envelope provided. Your views are important and will be used by the working groups as part of the management process.

For further information please contact:

The Severn Estuary Strategy
University of Wales, Cardiff
PO BOX 907
Tel: 01222 874000 Ext. 5102
Fax: 01222 987301
Email: [email protected]



1. Introduction

The estuary

The Severn Estuary, known in Welsh as Môr Hafren, is a unique place. For centuries it has been a focus for human activities, a location for settlement and a gateway for trading and exploration. Its ports have a great history which, together with modern industrial developments, provide employment and pride to many local people. Yet the estuary still holds a sense of wilderness valued by those who live, work and play in its environs. The Severn is one of Britain's biggest estuaries and it has the second largest tidal range in the world. This feature gives rise to the Severn Bore and to exposure of extensive sand and mud flats which attract many thousands of wading birds in winter.

The area covered by this report is shown on the inside of the front cover. The study area runs from just above Gloucester to Hurlstone Point near Minehead on the English coast and Nash Point (west of Barry) on the Welsh coast. References in this report to the estuary refer to this area. This is larger than the normal area defined as the estuary in order to include areas designated for conservation purposes.

The inter-related nature of coastal matters, means that boundaries are perhaps best defined by the issues rather than any physical feature. As a guide, the first major road inland from the coast will be used. However, we must bear in mind that when considering management of any coastal zone, natural and human activities well inland or to seaward may have an effect on the coast and the waters beyond.

The need for strategic estuary management

Over the last few decades, the scale and range of human activities has accelerated to influence and change not only the environment on land, but has also given rise to dramatic changes to our coastal and marine environment.

We must find ways to meet our needs whilst safeguarding what we value about the estuary for future generations to enjoy. To do this, we must consider the limitations of our estuary to absorb the impacts of human activities and find a way forward to which everyone is agreeable.

There are mechanisms to address each component of management of our coast, ranging from the statutory powers such as those of Government agencies and local authorities, to guidance being produced by Local Agenda 21 groups.

However to achieve successful management of a dynamic estuarine environment, where activities and developments can have far-reaching results, effective co-ordination and integration are key factors. These key factors rely on the communication and co-operation of all those whose actions will have an impact on the estuary. The Severn Estuary Strategy provides a way for all organisations and individuals to communicate about the estuary and their concerns.

The aim of the Severn Estuary Strategy is to further the process of estuary management. This can be defined as:

'a process which brings together all those involved in the development, management and use of an estuary within a framework which facilitates the integration of their interests and responsibilities to achieve common objectives'
(Department of the Environment, 1996)

The aims of estuary management are to:

To achieve this, estuary management should:

By identifying the issues and concerns of all those involved in activities and management on the estuary we will be able to plan together for a future that combines a strong local economy with a healthy estuary environment. The two are fully compatible with the principle of sustainable development. The long term goal of the Severn Estuary Strategy is to use estuary management to contribute to achieving sustainable development.

Sustainable development is:
"development that meets the needs of the present without compromising the ability of future generations to meet their own needs."

(The World Commission on Environment and Development, 1987)

It is important to note that:

"Sustainable development does not mean having less economic development: on the contrary, a healthy economy is better able to generate the resources to meet people's needs, and investment and environmental improvement often go hand in hand. Nor does it mean that every aspect of the present environment should be preserved at all costs. What it requires is that decisions throughout society are taken with proper regard to their environmental impact."

(Sustainable Development: The UK Strategy 1994)

What is the Severn Estuary Strategy ?

The Severn Estuary Strategy is an independent partnership. It was set up by local authorities, Government agencies and other organisations to achieve a co-ordinated approach to the wise use and management of the estuary. Representatives from a range of interests are already involved including ports and harbours, business and industry, conservation, recreation and archaeological groups.

The Strategy will work towards the development of the Severn Estuary Management Plan with everyone who is involved in the estuary.

The process to develop the Severn Estuary Management Plan is shown on page 6.

In addition we will publish a 'Who's Who of the Severn Estuary', collated from numerous organisations who have completed a 'Statement of Interest'. This will complement this Joint Issues Report.

The Project Manager and Project Assistant work in collaboration with a small group who meet monthly. This Working Group comprises of representatives from the local authorities on each side of the estuary, Countryside Council for Wales, English Nature, the Environment Agency and the Universities.

Progress Reports are presented to a Steering Group which meets every three months. This is a larger group including representatives of the ports, industry, and water companies as well as the organisations mentioned above.

What is the Environment Agency ?

The Environment Agency is a Government agency which regulates waste disposal to land, and industrial releases to air as well as safeguarding and improving the natural water environment. It has flood defence, water resources and fisheries functions and has duties to promote conservation and recreation in all its activities.

The Agency has many interests in the estuary and is committed to working with others to address the issues. One aspect of this is the production of a Local Environment Agency Plan for the estuary which will detail the actions the Agency is committed to over the next 5 years. The Agency will use this Joint Issues Report and the subsequent public consultation to help develop the Action Plan.

Where feed-back from the report shows that an issue requires action by the Agency this will be carefully considered and where possible entered into the Local Environment Agency Plan. It is hoped that other organisations will produce similar action plans, so that a co-ordinated approach to tackling the problems in the estuary can be made.

The provisional timetable for the Strategy is set out as follows:






June 1995

Setting up the Strategy

Local authorities and Government agencies got together to develop a plan




May 1996 to

May 1997

Collecting information on issues

Public meetings & consultation with key organisations







Who's who

May 1997


Sept. 1997

Public consultation

Everyone has an opportunity to comment




Summary of public views

Sept. 1997


June 1998

Working Groups consult on issues

Everyone can contribute




Recommendations reported


Development of the Draft Estuary Management Plan




Draft Estuary Management Plan


Public consultation




Summary of public consultation


Estuary Management Plan developed







Estuary Management Plan

2000 onwards



Stage 1:
Setting up the Severn Estuary Strategy

The Severn Estuary Strategy was set up in 1995 by a partnership of local authorities and government organisations with enough funds to appoint a Project Manager to co-ordinate activities.

The Severn Estuary Strategy then began to create partnerships with those who are involved in the estuary as groups or individuals.

Stage 2:
Identifying the issues

After setting up the Severn Estuary Strategy the next step was to identify the issues of concern to people involved in the estuary. More than fifty organisations and agencies such as the Crown Estate, Ministry of Agriculture Fisheries and Food, Government agencies and local authorities have direct regulatory control of activities in or near the estuary. Many other organisations, including voluntary bodies such as the Royal Society for the Protection of Birds, and recreational groups such as anglers and wildfowlers value the estuary and are very interested in the way it is managed.

To identify the issues we have:

Public meetings

A key objective of the Severn Estuary Strategy was to involve the users of the estuary from the beginning of the process. People who live, work or play around the estuary were invited to voice their concerns at a series of five public meetings held in Gloucester, Bristol, Cardiff, Burnham-on-Sea and Undy.

Over 300 people participated in the public meetings. At each meeting, the people formed into small discussion groups and answered the following questions:

1. What do you like and value about the estuary?

2. What use do you make of the estuary and do you have any problems or concerns about that use?

3. What are the most important issues for the future of the estuary?

Results of the public meetings

What people valued most about the estuary was a sense of wilderness. This is particularly surprising when one considers that the estuary is bounded by major cities like Bristol and Cardiff and over a million people live in close proximity to the coast.

Landscape, wildlife, community spirit and local distinctiveness were identified as important values. Perceptions of beauty, a pride in local heritage and the estuary's uniqueness were commonly reported.

Discussions of likes and values gave rise to a romantic and poetic charm: sunsets and sunrises, views from one side of the estuary to the other, mudflats, sandy beaches and a history that included pirates!

Some of the most commonly voiced concerns were about sewage and litter pollution of the foreshore. The other very important area of concern expressed by individuals at the meetings was the general management of the estuary, with people being particularly concerned about integration between plans and initiatives, regulation of water based recreation and public involvement. Other concerns included those relating to development, nature conservation, recreation, flood defence, fisheries, and agriculture.

The diagram on the following page illustrates the key concerns identified in the series of open meetings held in 1996. It is important to remember that this diagram reflects the concerns as perceived by those who have contributed to these meetings.

If you do not believe that this is a true balance of the issues, please let us know your views.

Statements of interest

Organisations and clubs with regulatory or general interest in the estuary have been asked to complete a Statement of Interest form. General information was requested such as area and scope of operations. In addition, questions were asked about the most important issues on the estuary and why the organisation valued the estuary.

There were two main reasons for these requests:

Over 200 of these Statements of Interest have been returned. The Severn Estuary Strategy also produced a flyer in March 1996 with a pre-paid reply slip which enquired about issues and values in the estuary. Over 100 of these have been returned.

Many of the organisations have sent very interesting replies. The Chepstow Boat Club, for example, when asked 'Why does the Chepstow Boat Club value the estuary?' gave this reply:

"There could be 43 different answers to this question!-varying from bird watching to fishing from photography to geology. Mostly just the pure joy of being on the river"

The 'Who's Who of the Severn Estuary' being prepared by the Strategy will be a very useful information source but further funding from industrial and commercial partners or others is still being sought for final compilation and printing costs.

Input from specialist and professional workers

Many specialists and professional workers have also contributed their views about issues around the estuary. This has included the input of many involved in different aspects of the management of the estuary such as Environment Agency staff , professionals on the Severn Estuary Strategy Steering Group and others who have contributed to the draft of this report.

Their help has been very valuable in ensuring that the technical and factual input to this report is as accurate as possible.


A draft of this report was distributed for consultation to over 100 people and groups. Their comments and ideas have been incorporated wherever possible. We are very grateful for their time and efforts. Key contributors are as follows:

Associated British Ports
Albright & Wilson
Bristol City Council
British Waterways
British Marine Aggregates Producers Association
Cardiff County Council
Countryside Council for Wales
D_r Cymru Welsh Water
English Nature
Forest of Dean District Council
Gloucester Harbour Trustees
Gloucestershire County Council
Lysanna Howard (former SES Project assistant)
Newport County Borough
North Somerset Council
Royal Society for the Protection of Birds
Sedgemoor District Council
Severn Trent Water Ltd
Somerset Wildlife Trust
South Wales Sea Fisheries Committee
South Gloucestershire Internal Drainage Board
South Gloucestershire Council
Susannah Bleakley (former SES Project Manager)
The Bristol Port Company
The Caldicot & Wentlooge Levels Drainage Board
The National Trust
The British Association for Shooting & Conservation
University of Wales, Cardiff
University of Exeter
Wales Tourist Board
Welsh Office
Wessex Water
West Country Tourist Board
West Mendip Internal Drainage Board

What happens next ?

Stages 1 and 2 are complete. This Joint Issues Report represents the beginning of Stage 3 - formal public consultation. It is hoped that this document will stimulate further discussion. Many more people have a valuable input to make which can help with the progress of the Strategy.

The organisations supporting preparation of this document are keen to ensure that the issues set out in it are considered by everyone with an interest in it, or responsibility for the estuary. Everyone is invited to record their views and attend a series of public meetings to discuss it. If there are issues which need to be added, we would like to hear about them.

The information from this document, the questionnaire at the back and further discussions will be used to formulate the structure of Working Groups. The groups will report back to the Strategy on their findings and the reports will provide the information needed to compile the final management document.

The publication of this Joint Issues Report is only the beginning of the process to improve estuary management. We need your help to continue that process!

Wider input is needed to ensure a balanced view of concerns on the estuary. We would particularly value more input from industry and the private sector, and from farmers and landowners.

2. Background to the estuary


Humans were first attracted to the estuary and the surrounding areas for its wildlife, natural resources and access. The estuary provided food from fishing, wildfowling and transport by sea. The surrounding semi-tidal marshes held wild boar, deer and huge prehistoric cattle known as aurochs. During the Industrial Revolution and modern era, industry and power stations have been sited on the estuary to enable them to use the ports, cooling water, cheap waste disposal and sand for building. With easier personal transport came recreational use of the estuary - evidenced by such Victorian seaside resorts as Weston-super-Mare and Penarth. This interest in recreation has now expanded to millions of people who enjoy and appreciate the estuary and wildlife for its own sake. This is reflected in the millions of members of such organisations as the National Trust, County Wildlife Trusts and the Royal Society for the Protection of Birds. The thousands of visitors to the internationally renowned Wildfowl and Wetlands Trust site at Slimbridge is one of the prime examples of this interest in the estuary.

The natural environment of the estuary and surrounding land, including the coal and iron ore of the adjacent South Wales valleys and the Forest of Dean, was the basis of the economy for centuries. With improved communications and globalisation of the economy the links have become less obvious but the economy and local environment are still intimately related.

Human social needs grew alongside the developing economic activity. The provision of transport, health services, education, recreation, goods and services required social organisation. Hence appropriate organisations and structures have developed, and over the years these have changed in response to changing needs and circumstances. A large number of organisations now contribute to the planning and regulation of the estuary and the surrounding coastline.

This chapter follows a three part structure which reflects these distinct yet inter-related facets of life in and around the estuary:

Economy and social structure

An energetic human environment

Just as the Severn is one of Britain's most active and 'energetic' estuaries in terms of its physical characteristics the same is true of its shore and water based human activity, and has been so for a long time.

Archaeological excavations accompanying recent economic projects such as the Second Severn Crossing, and the Seabank power station have reinforced evidence already available of the importance of the Severn lowlands for settlement and farming at least from the Iron Age. Other exciting discoveries, for example, the 13th century iron-ore carrier, uncovered recently near Magor Pill, hint at the historically-important role of the river itself as a commercial artery.

Population trends in the local government areas fringing the estuary are one obvious contemporary continuation of this same theme (Figure 2.1). During the last decade and a half all but three of them surpassed national average growth rates. Only the most urbanised one, Bristol, showed no growth over that period, but in practice its northern fringe settlements, beyond the tightly-drawn city boundary, exhibited the second greatest expansion of them all.

Furthermore, the social structure of this growing population reveals the large number of households in the highest social class categories (I and II), as well as high proportions of heads of households who are retired. In many cases these concentrations exceed the Great Britain averages.

Taken together, these characteristics reveal a growing population around the estuary, and particularly so in those social groups with both the time and resources to take part in outdoor leisure pursuits, as well as showing the highest levels of concern for environmental issues and of membership of environmental interest groups.

Figure 2.1: Population change 1981-1995 (%)

Turning to employment, data for the same areas (for 1991) reveal, not surprisingly, major differences in local job structures. However the employment structure for the Strategy area is remarkably similar to the Great Britain average. What is noticeable is that employment has increased at a much higher rate during the period 1981-91 for the Strategy area (6.4%) compared to Great Britain (1.2%) as a whole (Figure 2.2). The distribution of employees by area of course varies considerably - with Bristol and Cardiff dominating (Figure 2.3).

Figure 2.2: Percentage change in employees 1981 - 1991

Figure 2.3: Distribution of employees in the Strategy area 1991

Although, overall, primary sector dependence is low, rural parts of Gloucestershire and Somerset along with Monmouthshire have employment in this sector significantly above the regional and national average. In Tewkesbury, manufacturing accounted for almost half the jobs in 1991 and in Stroud and South Gloucester for around a third, while at the other extreme in the Vale of Glamorgan and West Somerset it fell to a tenth (Figure 2.4).

Throughout the estuary region, services are the major employment sector, as nationally - but the range of employment in Transport and Communication (2%-8%) is less than for other divisions in the service sector. Bristol (23%), Gloucester City (17%) and Cardiff (14%) stand out as centres for financial-based activities. The large and diverse 'other services' category provides between 18% - 41% of employment, with particular peaks, such as in Cardiff, with its capital city status and the Vale of Glamorgan, reflecting the greater relative emphasis on public and local administration and other general service sector employment.

Estimating the overall size of the economy that sustains such jobs as these in monetary terms is far less straightforward, but in 1993 the five (then) English and Welsh counties around the estuary (with a population of 4.9% of the U.K) had a combined Gross Domestic Product of some £26,000m, also representing 4.9% of the UK total, so Gross Domestic Product per head is the same as the national average.

Trends in the recent geography of unemployment around the estuary are most appropriately captured by its 11 travel-to-work areas (Figure 2.5). Here too, the region has become more energetic, sharing in the overall recent national decline of unemployment levels, with the improvements in Newport and Bridgend particularly marked, along with Cinderford and Ross (covering the Forest of Dean). Unlike a decade ago, all three are now at or below the equivalent national average, along with most of the English travel-to-work areas, other than those heavily dependent on tourism - Weston-super-Mare and Minehead. Ten years on, the Severn authorities' average unemployment rate (8.0%) remains below the national average (8.8%).

Figure 2.4: Employment structure by area 1981 & 1991 (%)

Figure 2.5: Unemployment 1986 & 1996 by travel-to-work areas.

A coastal economy

The tourist industry illustrates the importance of the estuary as more than just something to gaze at, live by and work by, but as a formal part of the present-day working economy. The ports and harbours around the estuary continue to play vital economic and social roles. The types of cargoes handled by the main ports of Avonmouth, Barry, Cardiff and Newport have changed over time. Current major imports include oil, coal, forestry products, animal feed, fertiliser, vehicles, marine dredged sand, exotic fruit and bulk cargoes. In terms of exports coal is no longer 'king' for the South Wales ports, but it does still feature amongst exports along with steel, aluminium, scrap metal, grain, chemical products and general cargoes. Clearly, the Severn itself forms a vital and multi-dimensional resource for the local economy.

A changing economy

Over the past decades there have been major changes in the economy of the Severnside area. These are reflected in its changing employment structure. Figures for 1981 and 1991 illustrate some of the recent changes. Some of these have had significant impacts on the physical environment. During the parliamentary or planning approval process such impacts have to be examined through environmental assessment, as with the Second Severn Crossing, the Seabank gas-fired power station proposal for Avonmouth/ Severnside, and the widening of the M5 over the River Avon. Other planned changes include the revitalisation of derelict waterfronts in the cities of Cardiff and Bristol. The former, aims to attract 1.5m visitors a year, and the harbourside scheme of the latter is the recent beneficiary of the largest-to-date Millennium Fund award outside London.

The estuary fringes of South Wales have also been very successful in attracting new inward investment, often from foreign manufacturers, the LG group of South Korea being the latest example. Their massive new Newport factory, to begin production in late 1997, should build up to a direct employment of 6,100 and have much greater knock-on effects. Equally, shopping patterns around the estuary will feel the impact of the M4-abutting Cribbs Causeway Regional Shopping centre of 725,000 sq ft of retailing space, under construction on Bristol's northern fringes, and traffic and house prices are likely to be affected by the consolidation of 4,000 procurement executive staff at the nearby Ministry of Defence, Abbeywood complex.

As part of ensuring the sustainable development of the estuary it is important to maintain a healthy economy. A healthy economy is able to generate the resources to meet people's needs, and investment and environmental improvement often go hand in hand.

Less planned and less welcome changes have been evident too. The defence-linked aerospace and electronics industries of Bristol and Gloucestershire have needed to adjust to the cutbacks in Ministry of Defence budgets just as Barry and Weston-super-Mare have shared the hardships of Britain's 'traditional' seaside resorts in attracting ever-more demanding, ever-more-mobile customers.

Finally, all these actual or potential changes, favourable or otherwise, lie within a political context that is itself changing. Local government reorganisation in April 1996 saw the ending of Avon County Council as well as other changes in Gloucestershire and Somerset, and the wholesale replacement of a two-tier structure by unitary authorities in Wales. Most of the present local authorities around the Estuary have changed their statutory responsibilities and geographic areas from their predecessors.

A divided human environment

Whilst the Severn Estuary itself is a single physical system from a social and economic perspective it separates its two shores both socially and economically. A recent catalogue of physical environmental research publications found 142 where the 'Severn Estuary' featured in the title or abstract as a geographical frame of reference. In the equivalent social sciences listing there were only four.

The most obvious division is in terms of administration, where the structures of local and central government and their supporting agencies find the Severn a convenient division line, as the detailed accounts of 'who does what' later in this report amply illustrate. Admittedly, some ad hoc groupings have become more prominent recently, partly triggered by externally-generated initiatives, such as Les Esturiales and the Atlantic Arc (both groupings based in France), or by external 'threats'. SCOSLA - the Standing Conference of Severnside Local Authorities - was the direct outcome of the possible building of a Severn Barrage, but has since been revitalised with a wider remit.

Although the Second Severn Crossing enhances communication between southern England and South Wales, day-to-day contact specifically between the two sides of the estuary region is limited. The cross-estuary Campbell Steamer summer schedules ended in about 1980. Commuting between counties across the estuary increased between 1981 and 1991 but still represents less than 1% of their labour force. The commercial rivalry between all the ports both now and historically is strong.

Less tangible but no less significant is the lack of a feeling of community identity across the estuary. Evidence collected for the recent local government reform on the English side revealed how inhabitants' sense of 'belonging' weakens once the scale of reference moves beyond the immediate neighbourhood or nearest town. A reasonable, if untested, inference is that still less allegiance would be shown to an entity spanning the estuary. The strength of involvement of people from Severnside in the process of responding to this issues document and resulting draft plans will give some indication of the extent of interest and allegiance, or indeed may help form it.

Finally, the changing human geography of the estuary throws into sharp focus differences among interest groups. Here common lobbying exists across the estuary, as with the Severn Estuary Conservation Group, formed in 1976 as an umbrella organisation for some 16 other bodies involved with local environmental issues. But this serves to underline the tensions between different interests, whether over big one-off conflicts (like Cardiff Bay) or through long-running campaigns as over whether to prioritise wetland conservation or agricultural improvements on the Somerset Levels.

Whatever detailed form decision-making and consultation in and around the estuary may take in the foreseeable future, how to resolve this same general conflict, between the interests of economic progress on the one hand and environmental protection and enhancement on the other, is likely to be one of the most intractable and frequently encountered of its dilemmas.

Organisational structure

Many different people and organisations have an interest in the estuary and the adjoining coastal areas. Some 50 organisations have powers to regulate or control activities in and around the estuary. Most, at one time or another, consult on their activities and plans either with other organisations, individual users, or the public at large. The organisational structure, or 'who does what' has changed over time, and may do so again in the future. An indication of 'who does what' is given at the beginning of each of the topic chapters in Part 2.

Some bodies have a number of different roles in relation to the estuary. For example, many of the land based controls are the responsibility of local authorities. There are 15 of these around the estuary as shown in Map 2.1. They include county councils, district councils and unitary councils. Some of the most important powers they have in relation to the estuary, and those who live nearby, include development planning, development control, involvement in emergency planning and coastal defence. These authorities also produce plans covering detailed aspects of the environment, wildlife and heritage, local economic development and tourism.

Many Government departments and agencies have important roles both in setting policy and direct management. The Welsh Office and Department of Environment originate policy for many of the activities which affect the estuary. The Department of Transport and Ministry of Agriculture, Fisheries and Food also have significant roles in relation to ports, fisheries and coastal defence. The Crown Commissioners control licensing for most aggregate dredging.

The Environment Agency has a major role in pollution prevention and control. The Agency is also involved in managing flood protection, fisheries and abstraction from the estuary and the rivers which flow into it.

To illustrate the joint working and links already established in the estuary:

Such complexities require careful planning and collaboration and is one reason why the Environment Agency produces Local Environment Agency Plans and is involved in preparing Shoreline Management Plans with local authorities. While these plans are not statutory, they follow Government guidance and are considered essential for good management of the estuary.

Control of ports and shipping is the responsibility of harbour authorities. They are a mixture of private and public bodies. The largest are private - Bristol Port Company and Associated British Ports (ABP) who control the major South Wales ports of Cardiff, Barry and Newport. Public bodies with these responsibilities include Sedgemoor District Council (Port of Bridgwater) and Gloucester Harbour Trustees.

Wildlife and conservation interests are primarily the responsibility of English Nature and the Countryside Council for Wales. Non-government organisations, such as the Royal Society for the Protection of Birds, the Wildlife and Wetlands Trust and the County Wildlife Trusts are also heavily involved in this area. Should the Severn be designated as a Special Area of Conservation, English Nature and Countryside Council for Wales will be required to ensure that a statutory management plan involving the relevant authorities in the estuary is established to protect conservation interests.

Many businesses have a direct interest in maintaining an efficient, effective and economic balance between the costs and benefits of their estuary links. Some of these use the estuary directly - for example, the ports, water companies, the Severn Bridge Company, companies using cooling water, and industry using the estuary for waste disposal. Other parts of the economy use the estuary indirectly. For example, the tourism industry which depends on people visiting the estuary.

Last, but by no means least, those of us who live around the estuary and enjoy recreational activities near, on or under the water. Individuals, interest groups, sporting organisations, conservation groups, academics, researchers, students etc. are as much a part of the organisational structure as the authorities and organisations listed above and throughout this Joint Issues Report and all have a role and a responsibility for its continued well-being.

Map 2.1


Physical features of the estuary

The Severn Estuary lies on the west coast of Britain at the mouth of five major rivers, the Severn, Wye, Usk, Avon and Parrett. It is one of the most important British estuaries with the largest tidal range in Europe and the second highest in the world (exceeding 12 metres at Avonmouth during Spring Tides). The funnel shape of the estuary produces the famous Severn Bore in the upstream reaches. It is Britain's biggest coastal plain estuary and has the fourth largest area of intertidal sand and mudflats in Britain.

Depths in the estuary and height of adjacent land

Above the Holm islands there are substantial areas of drying sandbanks and shallows interspersed with deep water channels which provide safe access to the ports further up the estuary. Downstream of these islands deep water predominates but a large area in Bridgwater Bay and along the coast to Minehead is relatively shallow.

The low lying areas of land around the estuary which are most at risk from tidal flooding are parts of the Gwent Levels, Somerset Levels and Vale of Berkeley. Map 2.2 shows areas of land less than 10 m above mean sea level.

Tides and the Severn Bore

As stated above the tidal range in the Severn Estuary is the second largest in the world. The range is greatest in the Cardiff to Avonmouth area and drops off towards the upper estuary and further out to sea. Tide tables for the Bristol Channel and Severn Estuary are produced by the Admiralty (Hydrographic Office) and published locally by Arrowsmith. There is significant variation from year to year in height and range of tides. The relative times of flood and ebb tide also change further up the estuary. On spring tides, there is about five hours of flood and seven hours of ebb at Avonmouth while at Gloucester there is about two hours of flood and ten hours of ebb. Times of high water are later further up the estuary and predicting the time of flood tide is important for the thousands of Bore watchers. The Bore is delayed (and usually disappointing) if there is high pressure or a lot of fresh water in the river but it is usually better if there has been a depression with strong south-westerly winds and low river flows. A leaflet giving predicted bore times and a star rating is published by the Midlands Region of the Environment Agency. There is also a significant bore on the River Parrett.

The Bore travels up the estuary at about 10 knots and current speeds in the upper estuary of up to 13 knots have been recorded. Within the navigable section of the estuary (below Sharpness) current speeds during spring tides can reach 10 knots in the Shoots Channel.

Another feature of interest to estuary scientists is the 'tidal excursion'. This is a term which refers to how far an object will be carried on a single tide. This is important for the study of pollution and sediments which wash back and forth on the tide. From the Holm islands maximum tidal excursions are 26 km for the north side and 37 km for the south side, showing that the currents are not the same on both sides of the estuary.


Salinity is measured in parts per thousand of dissolved salts in water. Sea water has a salinity of around 35 parts per thousand i.e. 35 g of salts in 1 litre of water and fresh water is usually less than 1 part per thousand. Although there is some evidence of salinity varying with depth (known as stratification) at the mouths of the rivers Taff and Usk at certain states of tide, the water is usually well mixed. This shows that in most respects the estuary is dominated by the tide rather than fresh water flow - hardly surprising given the tidal range observed.

Salty water may not penetrate above Sharpness during high river flows and neap tides but reaches Gloucester or beyond when big tides and low river flows coincide.

Fresh water flow

In the Severn Estuary there are several important sources of fresh water which enter via tributary estuaries, namely the rivers Wye, Avon, Usk, Rhymney, Taff, Ely and Parrett. As a round figure, the average fresh water flow into the estuary is about 300 cubic meters per second (26,500,000 cubic metres per day), about half coming from the rivers Severn and Wye.

Coastal processes - erosion, deposition and flooding

The coastal processes of erosion, deposition and flooding are driven by:

interpretation and technical appraisal of these processes is part of the shoreline management planning process which is discussed in greater detail in chapter 5 on coastal defence.


The high energy associated with the tides in the estuary has a large effect on the movement of sediments held in suspension and the distribution of bottom sediments. East of the line between Nash Point and Hurlstone Point large areas of the bed-rock are exposed - sometimes covered with a thin layer of unconsolidated sediment while there are areas of settled mud in the Newport Deep and Bridgwater Bay.

Upstream of a line joining Barry and Bridgwater Bay large quantities of fine sediment are redistributed according to the tidal state and range. During the full ebb and flood of spring tides similar levels of suspended solids may be found throughout the water column - and these may be up to 10,000 milligrams per litre. Towards slack water, the suspension settles out to form mobile layers of mud three metres or more thick in places on the bed of the estuary with suspended solids sediment concentrations of more than 50,000 milligrams per litre. It is estimated that the estuary carries over 30 million tonnes of suspended sediment on a spring tide. These dynamic conditions have resulted in the formation of characteristic seabed communities. Some of these are of high conservation value.
Map 2.2 Coastal processes
In the tidal River Severn near Gloucester sediments characteristic of the estuary migrate upstream during periods of low freshwater flow and give rise to concerns for navigation between Gloucester and Tewkesbury and in the Gloucester Sharpness Canal. These high levels of suspended solids also cause low oxygen levels in the tidal river as sediments which have become depleted of oxygen become re-suspended by the bore.

Life in the estuary

Estuaries are of great ecological importance being highly productive major nursery areas for marine species and key routes for migratory fish and birds. The flow of water down the rivers and from the sea brings a continual influx of nutrients. These nutrients are consumed by microscopic plant life which form the base of the food chain. The productivity of these microscopic plants is limited in the Severn Estuary by the abundance of suspended solids which gives the estuary its characteristic colour and restricts light penetration. The very mobile sedimentary regime, due to the large tidal range and strong currents, as well as the constantly changing salinity, creates a challenging environment for plants and animals. As a result few species have adapted to cope with the extreme conditions. However, because of the abundant nutrients those species that have successfully adapted often occur at very high densities.

The Severn Estuary is internationally important for the number of waterfowl it supports. It is such an important site due to its:

The estuary is also renowned for its migratory fish, including salmon and elvers (young eels), and the twaite shad. The rivers Severn, Wye and Usk account for more than 25% of the salmon caught in England and Wales and the estuary is the most important in the UK for elvers.

Saltmarsh is a significant and threatened habitat of the estuary's fringes. There are many types with both gradual and stepped transitions from bare mud to upper saltmarsh. Several nationally rare or notable species are present.

Some of the less well known but important features of the Severn Estuary are the reefs built by honeycomb worms, Sabellaria alveolata. A variety of other creatures such as juvenile lug worms, barnacles and sea squirts also use these reefs for shelter and attachment points. Whilst Sabellaria worms are widely distributed around our coast, the reefs in the Severn Estuary are unusual because they are sub-litoral and are some of the most extensive examples in the United Kingdom.

The broad intertidal sand and mudflats are home to species of worms, snails and crustaceans which provide food for the many migratory waterfowl (wildfowl and wading birds) that visit each year. In winter, the estuary regularly supports nationally important numbers of ten species of waterfowl whilst a further six species occur in numbers of international importance. It is also nationally important for several species of passage migrants in the spring and autumn, including ringed plover and whimbrel.

The lives of all the shore-feeding waders are governed by the tides and they feed both by day and night whenever the mud is exposed. At high tide they are forced to the top of the shore where they congregate in large roosts either at the tide edge or in nearby fields, like those at Stert Island in Bridgwater Bay and at Collister Pill near Newport. The sight of many thousands of wading birds wheeling and turning in flight as they prepare to settle at such roosts is one of the finest wildlife spectacles in the estuarine wilderness.

Other breeding birds around the estuary have declined with habitat loss and increased human disturbance. A few ringed plover and oystercatcher still breed in scattered locations whilst many shelduck have moved from the mainland to the more secluded island of Flat Holm to breed.

In winter the Wentlooge, Caldicot and Somerset Levels together with the lowlands at Clevedon and the Vale of Berkeley support vast flocks of redwing, fieldfare and other visiting thrushes.

The presence of salmon in an estuary or river is often taken as a measure of the health of the environment. It does reflect the quality of the water, but not the biological diversity or productivity of the estuary as salmon do not feed there whilst on migration. There appears to be a long term decline in numbers of salmon, in line with other North Atlantic fisheries.
Although there is a general interest in salmon and an occasional sighting of a fish jumping the weirs at Gloucester or Tewkesbury, the fascination with salmon in the estuary is centred on the traditional methods of fishing. The 'fixed engines' or putchers are a feature of the inter-tidal area of the estuary. These consist of rows of baskets - traditionally withy but now steel and plastic - which catch salmon swimming near to the shore (normally on an ebb tide). The currents are so strong and the estuary so muddy that the fish are not able to see or avoid these traps. Some individual fishermen near Lydney walk out across the sands at low water and fish with hand held 'Lave Nets'. The fishermen watch for the tell-tale line of the fish's wake and scoop the fish into their nets. This is a very dangerous occupation and even some fishermen who have worked the river all their lives have been caught by the tide. Other traditional methods of fishing have been lost over the last 20 years as the market for Severn Salmon has fallen away with the advent of cheap 'farmed' salmon.

The estuary is the most important in the country for elvers. High concentrations of these are found swimming with the tide along the estuaries and tidal rivers on spring tides between March and May. They are mostly caught at night in the hand held nets of the fishermen. The myriad of small lamps on the banks of the estuaries and tidal rivers during these periods is very much a part of the character of Severnside. Elvers used to be a local delicacy or sport (there was an elver eating contest at Frampton until 1994). However, it is now much more of a commercial activity with one kilo of live elvers for export fetching over £200. This does lead to problems of trespass and damage to land by the estuary and conflicts between fishermen and allegations of poaching.

Many species of fish have been recorded in the estuary. Fish known to depend on the estuary to complete their life cycles include those which migrate between the sea and rivers. These include the allis and twaite shads, members of the herring family, the sea and river lamprey, and of course Atlantic salmon and eels.

To the seaward side of the sea wall, saltings are often found consisting of stretches of grass leading to low earth cliffs with saltmarsh or mud flats beyond. All plants beyond the sea wall are likely to be covered by the tide at some time so only salt-tolerant species can survive. Most parts of the upper saltings are grazed by sheep or cattle and consist of bent and fescue grasses and the flowering sea pink, sea milkwort and sea spurrey. The middle zone of the grass saltings shows the change from the green coloured fescue to the grey-green of the common saltmarsh grass at a lower level.

Below the earth cliffs the native glasswort and annual sea-blite has been replaced in many places by Spartina grass of which there are several. Many have been deliberately planted in many areas to trap silt, so raising the level of the shore and giving protection against erosion in some more sheltered areas. Eel grass maintains a hold but may be declining in the estuary. This is our only truly marine flowering plant and all three species found in the Severn, are nationally scarce.

The influence of the sea is not entirely checked by the sea walls, salt water may percolate through into the drainage channels on the landward side allowing salt tolerant sea sedge, celery leaved crowfoot and horned pondweed to replace some of the freshwater plants in the ditches.

Sub-tidal sandbanks are permanently covered by sea water up to a depth of 20 metres. These large areas of sand and sediment occur in the middle and outer estuary and Bridgwater Bay.
The broad intertidal mudflats and sandflats are exposed at low water and have different species living in or on them depending on the proportions of mud and sand. Where there is low salinity and a muddy bottom such as at Berrow Flats and the mouth of the River Usk, there are mud snails, Baltic tellin, and bristle worms such as catworm and ragworm. Other areas of sand have communities including lugworms and sandhoppers. The common shrimp is also abundant in the estuary and is a significant part of the diet of many young fish.

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