CASE STUDY 9 - RTPI.org.uk - Royal Town Planning … PROPOSED SALISBURY BYPASS ITS POTENTIAL IMPACT...

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CASE STUDY 9

TITLE: A DROP IN THE OCEAN

ISSUE: A study of the potential impact of a bypass scheme on the water environment.

RESOURCES: Location/route plan, background information about the originalSalisbury Bypass proposals, pressures on the water environment with photos, summaries, photos / information on Sustainable Urban Drainage Systems, bubble diagram, map exercise, newspaper articles,summaries of groups / individuals with an interest in the Salisbury Bypass.

TASKS: l Identification of key pressures on the water environment and effect of new development.

l Analysis of newspaper article relating to flooding.

l Route choosing exercise: Justifying a route for the Salisbury Bypass with least impact on the water environment.

ROLE: Taking on the role of an interested party – letter writing exercise. Scope for role play/inquiry exercises involving different interest groups.

CONFLICTS: Impact of proposal on water environment (pollution, flooding, recreation, wildlife) as against the beneficial effect of bypass (less pollution in city centre, reduced risk of traffic accidents).

ISSUES Pressures on the water environment from new developmentINVOLVED : (flooding, pollution and overuse). Importance of effective

water management - working with nature and “holistic” management.

OPTIONS: l Types of pollutant.

l Control of urban runoff.

l Mitigation for development.

l Public Inquiry Exercise.

DECISION: Decision making exercise involving choosing the most water environmental friendly route for the Salisbury Bypass.

THE PROPOSED SALISBURY BYPASSITS POTENTIAL IMPACT ON THE WATER ENVIRONMENT


CASE STUDY 9

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INTRODUCTION:

.....WAR OVER WATER SUPPLY.... MAJOR FLOODS OBLITERATE THE CAPITAL

.....WATER RATIONING IN PLACE FOR THE SECOND TIME THIS YEAR.....

FACT OR FICTION?

Water is a resource which is vital for all life on earth and yet a plentiful supply ofclean water is taken for granted by the majority of the western world. Water has avast number of uses which impact on many areas of our everyday lives. Water playsa major role in our domestic environment and is essential for health and hygiene.Many recreational activities revolve around the water environment and it is central tonumerous industrial activities. It is used by farmers to grow food and to support thewildlife and the beauty of our rivers, streams and wetlands.

This role will become increasingly important given the increase in the demand forwater generated by new developments in the future.

The increase in water usage has placed a huge demand on the supply of water, butare sources of water supply limitless? At a local level, during a dry spell, some watercompanies have had to control the use of water through a hose pipe ban in order toensure reservoirs contain enough water for essential uses all year round. At suchtimes it is important to ensure that water is not wasted on non-essential uses suchas washing cars or watering lawns.

In managing water resources for the future, consideration should not only be given tothe adequate sources, or quantity, of water available, but also to how water qualitycan be protected and how the risks posed by pollution and flooding can be managed.

In summary, water is a precious and versatile, but vulnerable and finite resourcewhich requires sensitive management. Through the consideration of water, its uses,and also threats to it, this study aims to explore some of the current issues associatedwith water management. The headlines at the beginning may be exaggerated, butthe following study aims to show how appropriate water management now canensure that risks to the water environment posed by development and increasingdemand can be minimised.

THE SALISBURY BYPASS – CASE STUDY

The need to travel is fundamental to the majority of today’s lifestyles, whether thejourney is a weekly car-trip to the local shop or a long-haul jaunt around the globe.The issue of providing for the need to travel, however, is a contentious one. Various options have been put forward which aim to minimise the adverse effects oftravelling. These options include increasing the use of public transport, making surenew development is planned so as not to increase the need to travel (e.g. locating new houses in areas which enjoy good transport links, employment


CASE STUDY 9

opportunities and recreation and leisure facilities), investing in new forms of less-polluting vehicles and building more roads to provide for the growing number of cars. Each option has its own advantages and disadvantages and some mayconflict with each other.

This case study is concerned with the effect of building new roads around towns andcities to take vehicles around, rather than through, already congested areas whichwere never designed for a high level of car use. The “Bypass” is one measure whichhas been used to relieve the pressure of congestion on existing towns and cities.

There are a vast number of issues to be considered when proposing a bypass.These include the effect on traffic congestion, local residents, local businesses,recreation areas, conservation areas, the general environment and how it fits in withthe overall concept of "sustainability". This study, however, is concerned only withthe effect of the bypass on the water environment and will focus on a recent controversial bypass scheme in Salisbury, Wiltshire which had important implicationsfor water management.

SALISBURY BYPASS - BACKGROUND

Salisbury is the commercial and recreational centre of South Wiltshire and hasstrong historic roots focused on the cathedral and Old Sarum – both of which aremajor tourist attractions. Nearby Wilton is much smaller but also steeped in history,being the ancient capital of Wessex. These two communities stand at the heart ofSouth Wiltshire and provide facilities which serve many of the surrounding villagesand hamlets.

The main road carrying traffic into and through Salisbury is the A36. The road is narrow and winding throughout much of its length and the large number of heavygoods vehicles can create dangerous and environmentally damaging conditions forvillage residents. The road also has a poor accident record.

The proposed A36 Salisbury Bypass was intended as a means of bringing trafficrelief to the historic City of Salisbury by diverting vehicles around Salisbury centre. It aimed to reduce traffic travelling in and around Salisbury by as much as 30%.However, following a review of the various options and a change of policy, the government abandoned the proposal for the bypass in 1998. A new integrated transport strategy for the city is now being considered.

Three potential routes for the bypass were originally identified and put forward forconsultation in April 1988. These options were identified as the Blue Route (south-ern), the Yellow Route (northern) and the Red Route (combining Blue and Yellowand passing south of Salisbury) The three routes are shown in Fig 1. The cost ofconstructing this route was estimated to be around £76m (at 1995 prices).The government’s preferred option was the red route.

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CASE STUDY 9

THE RISKS

Water is arguably nature’s most precious resource and is essential for life. Sensitivemanagement of the water environment is therefore vital. The main issues associated with water management are threefold:

l Flooding (too much water) l Pollution (contamination of water) l Overuse (increasing demand)

To a greater or lesser extent, these three issues are all apparent in the case of theSalisbury bypass and each will be dealt with in turn.

1. FLOODING – a natural hazard.

As well as being a useful and versatile resource, water can also be an immenselydestructive force. Flooding is the world’s biggest natural killer, causing 40% of alldeaths due to natural causes and, throughout the world, this figure is increasing(Prosser and Bishop, 1995). Accurately predicting where and when a flood incidentwill occur is very difficult. Salisbury city is located in a basin at the confluence of five major rivers which have wide flat floodplains. Flood risk is therefore a majorconsideration.Rivers and floodplains are fundamental parts of the water environment. Generally,their existence is a result of natural forces and processes which must be respected

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Reproduced with the kind permission of Ordnance Survey © Crown Copyright NC/1308/00


CASE STUDY 9

if flooding problems are to be avoided. The flooding of floodplain areas is both natural and desirable, where it can occur without risk to human life and property.The effectiveness of rivers and flood plains to convey and to store flood water, andminimise the damage caused by flooding, can be adversely affected by humanactivity, especially by development which physically changes the floodplain andreduces the natural ability of land to accommodate water.

Before the Town and Country Planning system was established, there was littleattempt to steer development away from river and floodplains. Many of our settlements, including Salisbury, have historically grown around river crossing points where transport routes converged and, consequently, the floodplains andchannels of many major rivers became very restricted within densely developedurban areas. Inevitably these areas could not accommodate large storm flows, andserious flooding of developed areas occurred. In some instances it has been possible, at considerable public expense, to reduce the flood risk in such areas by engineering works, but it is not always a viable option.

Only towards the end of the 20th Century has the natural function of floodplainsbeen properly valued. It is now appreciated that it can be more cost effective towork with nature rather than to fight against it. Current uncertainties over possibleclimate change and associated sea level rise make the need to safeguard floodplainareas particularly important.

At many locations, the increasing recognition of the ecological value of floodplainsas well as changing agricultural policies are providing opportunities to re-establishthe natural functions of floodplains. Much floodplain land is already recognised to be of high ecological value and many river valleys have statutory wildlife and conservation status. The floodplain meadows surrounding the City of Salisbury arean important part of the wetland complex and are of considerable ecological andconservation interest. Apart from their plantlife, the flood meadows also supportoverwintering wildfowl and breeding waders, whilst the remaining ditch system contains a rich aquatic invertebrate fauna and provides a habitat for amphibians.

In many places where floodplains have been developed in the past, flood defencemeasures have subsequently been necessary to reduce the risk of flooding to nearby development at these sites. Such locations are sometimes referred to as “defended areas”. Typical flood defence measures include flood walls or embankments, the raising of land above flood levels, and increasing the capacity ofriver channels to carry flood waters.

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At some locations, redevelopment schemes may provide an opportunity for therestoration of the natural floodplain or at least the removal of obstructions to floodflow routes, and enhancement of ecological value.

NEW DEVELOPMENT AND ITS EFFECT ON FLOOD RISK TOEXISTING PROPERTY

New development both in and outside of the floodplain can have an effect on floodrisk and flood levels elsewhere.

The effects are summarised as follows:

l Development in the floodplain could be at risk from flooding itself.

l In times of flood, development in the floodplain may obstruct the flow of flood water. This can increase flood levels upstream thus increasing upstream flood risk.

l Development in a floodplain may reduce the amount of land available for flood water storage. Loss of flood water storage reduces the ability of the floodplain to store floodwater which results in an increase in downstream levels, thereby increasing downstream flood risks.

Surface water drainage from areas outside the floodplain can also have an effect onflood risk. In many cases development will result in an increase in concrete andpaved areas, through which water cannot penetrate. Water therefore runs off theseareas in greater volumes and at a quicker rate than previous, causing higher flowsin rivers for shorter periods of time. This can result in an increased flood risk downstream. The alteration of flow patterns, with higher flow rates for shorter periods and reduced flows at normal times can dramatically alter the river habitat.Increased flow rates can cause erosion of riverbanks and beds, resulting in thedeposition of material downstream. These changes can destroy habitats and alterthe natural flora and fauna.

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Where there is an overriding case for development in a floodplain, then measuresneed to be taken to protect the new development, commonly called “mitigation mea-sures”.

These may include the following:

l Protecting the proposed development by providing an approved flood defence scheme. This has implications for long term maintenance.

l Introduction of an adequate flood warning procedure for existing and new residents of an area.

l Compensating for developed areas of floodplain by excavating new a new floodplain at a different location

The red route of the Salisbury Bypass would have involved the construction of atotal of 25 bridges, some of which would cross major rivers. It was proposed thatsuch bridges would be designed with large spans in order to minimise disturbanceof the floodplain and its habitat. Flood compensation works and channel diversionswould have also been carried out.

It was also proposed to culvert some minor watercourses along the route of thebypass. Culverting is often considered when development over a watercourse isproposed and usually involves laying a pipe under the development for the watercourse to run through. This has a number of flooding and conservation issuesassociated with it. When a culvert gets blocked, water which would normally flowthrough it has nowhere to go and can create flooding problems. In addition, culvertsinterrupt the natural wildlife corridor of a river, which can create problems for migrating fish and bankside wildlife.

Culverting, flood compensation works and channels diversions can all have aneffect on natural river processes such as sedimentation and bank erosion. Thesefluvial processes are key factors in the ability of a river to convey flood water andmaintain its conservation value. Some areas of Salisbury are particularly susceptibleto flooding already, even in only moderately severe storm. Mitigating the effect of the bypass on the natural flow patterns of the river would be a vital considerationin protecting areas potentially at risk from flooding.

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CASE STUDY 9

POLLUTION

Pollution can enter the water environment from a variety of sources. Highly publicised pollution incidents often involve oil tankers and industrial installations.

Some naturally occurring events are also seen as causing pollution. For instance,some rivers carry large amounts of small mineral particles, called silt. The silt canbe washed into the river from land after heavy rainfall and turns the water brown. It can also be disturbed by carrying out construction works on or near a watercourse. The following article relates to a pollution incident during work on abypass similar to that proposed for Salisbury.

Work Stops on Bypass after Pollution - 24 March 1999“Work on part of the Fishguard Western Bypass scheme was stopped at the requestof the Environment Agency Wales last Friday (19 March) following an incident whenthe Drim Brook was polluted with silt.

The Environment Agency was alerted to the pollution by the general public onFriday. Agency biologists have continued to investigate the cause and impact of thedischarge – thought to involve a large quantity of silt – over the weekend. The contractors are carrying out anti-pollution measures to minimise the impact of thework including the redirection of the stream and the construction of settlementlagoons. No dead fish have been discovered at this stage.

Silt can clog the gills of fish, killing them by suffocation and spawning sites can bebadly affected. Insect habitats on the bed of the river can be destroyed, removing avital source of food for fish. It can also coat the leaves of aquatic plants, limitingtheir growth. In addition, build-ups of silt can block watercourses and increase therisk of flooding during heavy rainfall.

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SUMMARY

l Flooding is the world’s biggest natural killer.

l Human activity has traditionally been concentrated around the floodplain.

l There is a growing recognition of the natural function of the floodplain and its incompatibility with traditional settlement patterns.

l Development outside the floodplain can also have an effect on flood risk.


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The article is relevant as the rivers around Salisbury are particularly important fortheir conservation value and support a wide range of fish. Downstream of Salisbury,river water is taken, or “abstracted” from, the River Avon for water supplies, fishfarming and spray irrigation. Three large fish farms also use the river to grow troutand there are also game and coarse fishing interestsOne source of pollution closely associated with new development, and in particularroads like the proposed Salisbury bypass, is that of urban runoff. Rain falling onimpermeable surfaces, such as roads, rapidly picks up any contaminants present,such as dust, oil, litter and organic matter. The impact of this material being flushedinto a watercourse can be dramatic, with a high level of silt blanketing stream lifeand a rapid reduction in oxygen levels. As a consequence of these repeated discharges, life in receiving streams may be severely restricted and any fish whichdo venture into them risk suffocation in the event of a storm.

With a bypass such as the one proposed at Salisbury, there was also the potential pollution risk associated with a tanker involved in an accident discharging its load ofoil, petrol or other potentially polluting substance which could have a dramatic effecton nearby watercourses.

GROUNDWATER PROTECTION

Groundwater provides a large resource for public water supply. Proper managementcan preserve the amount and quality of groundwater. This, however, is a difficulttask. There is the problem of space because, unlike rivers which flow in definedchannels, in many parts of the country groundwater is present everywhere beneaththe ground and is at risk from human activity. There is also the problem of timebecause, due to the very slow movement of groundwater, any pollution problemscan take a long time to show themselves and can be virtually impossible to cleanup. Groundwater is therefore particularly at risk from pollution which may accumulate over years, such as road runoff. These problems can be very difficult to deal with, as they are unseen and not easy to deal with. The chalk beneathSalisbury is classified as a major aquifer and contains large quantities of high qualitywater. The area is highly productive and is of regional importance as it is used forlarge abstractions of drinking water. Particularly significant are the aquifers in thevicinity of Salisbury itself, over which the bypass crosses.

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The use of interceptors was the main method proposed for removing pollution fromrunoff from the Salisbury Bypass. An interceptor is a device which traps some pollutants, preventing them from discharging into watercourses and wetlands.However, interceptors require regular maintenance, without which they can becomeineffective and allow pollutants to pass into the water environment.The construction phase of the bypass would have involved the use of machineryusing diesel fuel. Construction would also have involved the importation of roadmaking materials such as bitumen and aggregates. Deliveries of materials is usually made by lorries which require the construction of access roads. Cleaningand servicing of equipment also takes place on site. Ensuring that no pollutantsenter the water environment is therefore especially important during the constructionphase of a bypass. It would be vital that any potentially polluting material be kept in a secure place and measures taken to ensure the risk to the water environment isminimal. When construction is completed, fires and spillages from chemical and oiltankers can be a major pollution threat. In 1996, there were 1915 water pollution incidents in surface waters arising from transport. Of these, 73% were due to roadtransport.

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SUMMARY

l Pollution can arise from natural as well as non-natural sources

l Pollution risks can be particularly large during the construction phase of development.

l Groundwater pollution can be particularly difficult to clean up because it is unseen and difficult to detect.

IMPACT ON WATER RESOURCES

Can you imagine Britain without its rivers and streams, wetlands and all the wildlifeand plants that are taken for granted? Imagine an arid, dry dustbowl.

Unthinkable isn’t it? Yet parts of England and Wales are now facing more periods ofdrought following the driest two years for two centuries (Since 1990 the country hassuffered some of the severest droughts of the century). Added to this is the fact that,with an increasing population and more homes being built, the demand for water isincreasing steadily. Estimates vary, but a typical person in the UK uses between 140and 190 litres of water per day. (In some developing countries people have to survive on as little as 9 litres per person per day). Some predictions suggest that,without managing demand, by the year 2020 we will need almost a third as muchagain per person. But what has this got to do with Salisbury bypass? What effect could the construction of a road have on the quantity of water available


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for public supply? When considering a bypass scheme the issue of overuse maynot be as big a consideration as, for example, pollution or flooding. However, theconstruction of a bypass may have a direct impact on the underground waterresources which are used for public water supply.

The effect of large areas of hard impervious surfaces, such as roads, on flood riskhas been demonstrated earlier in the study. Water which would have penetrated intothe ground would rapidly run into watercourses and ditches at higher rates thanusual thereby increasing the risk of flooding. However, in addition to increasing floodrisk, hard surfacing can also have an impact on underground water resources andareas of wetland. Water which would normally penetrate into the ground to feedareas of wetland and recharge underground water supplies would be lost to the seavia the river, thereby depriving an important water resource of its natural supply of

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SUMMARY

l At present, the demand for water is steadily increasing.

l Areas of hard, impermeable surfacing can have a dramatic effect on the amount of water available as groundwater for public supply.

water.THE THREAT TO WILDLIFE

As well as being essential for us to live, water is just as important for animals andplant life. Rivers provide a number of different habitats which are homes for a greatvariety of plants and animals. These include not only fish and waterfowl but lessobvious creatures such as mayfly larvae crawling on the riverbed, snails grazing onthe vegetation and dragonflies in the air above. There are also many reeds andother plants which grow only along river banks. Whether in the uplands, the low-lands, deep in the countryside or running through the towns and cities, rivers areessential to the survival of many species. Even in intensively farmed areas, whichcan be damaging to wildlife, rivers provide a refuge for plants and animals andserve as “wildlife corridors”.

Chalk river habitats are very important for wildlife and often contain river water crowfoot (Ranunculus), species of starwort, watercress and lesser water parsnip.The rivers around Salisbury are fed by groundwater and produce clear waters andstable flow and temperature. This provides conditions that support a rich diversity of invertebrate, plant and fish life. The area is protected by a wide range of conservation designations, including SSSI (Site of Special Scientific Interest) and


CASE STUDY 9

SAC (Special Area for Conservation).Humans have interfered with river systems for a variety of reasons. There may be adesire to use a river as a drainage channel, with water being moved as quickly aspossible towards the sea. Rivers are also deep dredged for the navigation of bothcommercial and pleasure craft. Banks are piled with sheet steel to control erosion orallow riverside construction. Chanelled rivers of uniform width often replace pools,riffles, shallows and meanders and bankside trees are removed because theyimpede the progress of machinery. This makes the river more efficient as a channelfor carrying water but can substantially affect its nature conservation value.

Away from the river may be fen, marsh and bog whose watertables often depend on adjacent river levels, and where wildlife is at risk from any changes which reducewetness in the ground. River engineering schemes which destroy river habitats, alsolower river levels and water tables in the surrounding land. As a result, associatedwetlands begin to dry out and lose the plants and animals that depend on wet conditions. Pollution is also a major threat to the wildlife in water environment, stripping rivers of essential oxygen thereby suffocating plants and animals.

The proposed bypass in Salisbury would have crossed a number of rivers on itsroute around Salisbury, including the Avon. The River Avon and its tributaries are ofnational and international importance as a fine example of a chalk river system.Chalk rivers are naturally scarce in the European context and England has the principal resource of chalk rivers in Europe. The Avon is recognised as one of thebest chalk rivers in Europe and as one of the premier British rivers.

The upper tributaries of the Avon and the main river itself are typical chalk rivers andstreams, characterised by their clear water and abundance of aquatic plants. There is considerable habitat diversity in such rivers including submerged floweringplants and invertebrate fauna.

In addition, many people use the river and surrounding area for recreation. There isan extensive public footpath network covering the River Avon flood plain with theAvon Valley long distance foot path running from Salisbury to Christchurch. A canoeclub operates in Salisbury itself.

MANAGING THE RISKS

The main aspects of flooding, overuse and pollution have been outlined separatelyabove. However, in order to manage water effectively, the three aspects have to beconsidered simultaneously. For example, in deciding where new development is tobe located, the effect on the whole water environment must be considered.

An idea which has been put forward as one potential solution to the issue of managing the water runoff from new development is that of Sustainable UrbanDrainage Systems, or SUDS. SUDS work on the principle of maintaining the naturalcycle of water. One example of a SUD is a porous pavement. Porous pavements

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allow water to penetrate through into the ground, rather than draining off. This has three effects:

l It allows water to penetrate into the groundwater below and renews water for public supply.

l It allows water to be filtered for pollutants which then stay in the surface layer.

l Because it reduces the runoff from development, it minimises flood risk.

This is an example of a “holistic” approach, which takes into consideration the wholewater environment (i.e. issues of flooding, pollution and water resources) and couldhave been implemented on a scheme such as the proposed Salisbury Bypass.

Other measures can also be taken to mitigate the effect of new development. Suchmeasures include the use of “buffer zones” which are areas of land retained in theirnatural state and are located between new development and sensitive areas. A wellvegetated strip of land next to a river can remove chemicals and silt from waterbefore they have chance to enter the river. Buffer zones can benefit water quality,protect wildlife in a river or wetland and maintain the river corridor for freedom ofmovement along the river.

CONCLUSION

The proposed Salisbury Bypass was eventually rejected in the light of changingGovernment policy on both the Environment and Transport. However, the watermanagement issues raised by the proposal are increasingly becoming major factorsin determining where new development of all types is located today. Mistakes of the past are being recognised and there is a growing realisation that it is usuallybest to work with, rather than against, nature in the management of floodplains, in maintaining water resources and in keeping the environment pollution-free.

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CASE STUDY 9

THE ENVIRONMENT AGENCY

The Environment Agency is a Government organisation which amongst other things,is responsible for the protection and, where necessary, enhancement, of the waterenvironment. The Agency recognises that environmental problems are interrelatedand need to be dealt with together. To achieve this the Agency has adopted an integrated, or holistic, approach to understanding, managing, regulating and improving the quality of air, land and water.

The Agency is consulted on various types of new development which may have animpact on the environment, and makes comments on such issues as identified inthis study. The comments are usually sent to local authorities when a planning application for new development is submitted, or when a development plan for anarea is being produced. However, the Agency is also involved in influencing developers before an application is made through environmental education and discussion.

The Planning System is viewed by the Environment Agency as an essential tool inachieving aims of environmental protection and enhancement as it gives the opportunity to influence the location and form of new development. Planningresponses are formulated by Planning Liaison Officers who work in EnvironmentAgency offices all over the country and use their expertise of different areas of theAgency to protect the environment against harmful development and also seekopportunities to enhance it.

If you are interested in a career with the Environment Agency, or have any questions about Agency work then please contact your local Agency Office, or The South West Regional Office; Manley House, Kestrel Way, Exeter. EX2 7LQTel: 01392 444000 Fax:01392 444238

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GROUPS / INDIVIDUALS WITH AN INTEREST IN THE SALISBURY BYPASS

Other users of rivers and wetlands may also be affected by the construction of abypass.

Car user“The bypass will be a huge improvement on the present situation, nomore time spent stuck in traffic with all those fumes! I’m sick of it!”

Fisherman“I’m very worried about the effect of the bypass on the fish population in the river. If a lorry carrying petrol crashes into the river then it would be disastrous. All that noise too. The brown trout and salmon are alreadydeclining.”

Canoeist“Lots of people use the river for recreation. If they start mucking aboutwith flows in the river then we are all in trouble.”

Conservationist“There is no telling what effect the bypass will have on the rivers and wetlands in Salisbury. These are nationally important conservation areasand mustn’t be compromised.”

Resident living near the bypass“I take my dogs for a walk down by the river everyday. This bypass isgoing to badly affect my enjoyment of the river. And what about my property? It’d lose so much value. Why should I be penalised?”

Salisbury Centre Resident“We’ve had to put up with all this traffic for years, its about time someonedid something about it. If the bypass reduces traffic in Salisbury then it’llbe a Godsend. The problem is all these conservationists who think weought to protect the countryside but don’t have to live right in the middle

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of the traffic.”QUESTIONS AND TASKS

1. Use the bubble diagram to show the three main risks associated with water management. Note down two effects of what happens when each risk becomes reality.

2. What is culverting and what effects can it have on rivers?

3. Read the following newspaper article. (flooding article) (Water Resources- Process and Management) What can be done to reduce the damage caused by flooding?(decent flood warning, defences, steering development away from the floodplain, raising floor levels etc)

4. Why is the pollution threat particularly great during the construction phase of the bypass?

5. What is the main benefit of using Sustainable Urban Drainage System (SUDs)in new development?

6. Why do the different people have such contrasting understandings and opinionsof the Salisbury Bypass scheme and its implications? Take on the role of one of the interests and, using the resources within the case study, write a letter to the local council expressing your views and arguments for or against the Salisbury Bypass.

7. In planning the location of new development, consideration must be given to siting it in a place where the potential for it to cause pollution will be minimal. If you were to plan a route for the Salisbury Bypass which had the minimum impact on the water environment today, use the resources and plans provided to decide where it would go. Justify your choice.

l How does it differ from the proposed route?

l Prepare a schedule of benefits and disbenefits of the different routes.

8. What are the advantages of having one organisation which is responsible for the whole of the water environment? Are there any disadvantages?

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SALISBURY BYPASS

Lives atrisk

Flooding

Reducewater

supply

Pollution

Pollutewater

supply

Fishkilled

Damage to

property

Damagewildlife

Impact onwater

resources

WORKSHEET FOR QUESTION 1

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SALISBURY BYPASS

WORKSHEET FOR QUESTION 1

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CASE STUDY 9

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