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A303 /A30 /A358 CORR IDOR
Feas ib i l i ty S tudy Summa ry
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Con ten ts
1. Introduction...4
2. Context ...5
3. Study aims and objectives ...6
4. Current andfuture situation ...8
5. Investment options...11
6. Investment cases...13
7. Study outcomes ...18
Annex: Reference Group Members ...20
1 . I n t roduc t ion
1.1 The A303/A30/A358 corridorfeasibility study was one of six such studies undertaken bythe Departmentfor Transport tolook at problems and identify potential solutionstotackle some ofthe most notorious and long-standing road hot spotsinthe country.
1.2 The commitmenttothe studies was part ofthe biggest ever upgrade of the strategic national roads network, announced bythe Governmentat thetime ofthe2013 Spending Review.
1.3 The studies have been progressed alongsidethe Highways Agency’s Route Strategy programme, whichis consideringthe current andfuture performance ofthe entire strategic road network,in ordertoinform futureinvestment decisions.
1.4 This summary documentforthe A303/A30/A358 corridorfeasibility study outlines:the study’s aims and objectives;the current andlikelyfuture problems alongthe route; the development and assessment of potential investment options; theassessment of business cases for prioritised investment options;andtheinvestment decisions and outcomes announced by the Governmentinits RoadInvestment Plan1.
2 . Con tex t
2.1 The A303 corridor fulfils animportant rolein connecting the South East and London withthe South West region.Itis dualled over much ofits length but betweenthe M3 motorway, A358 and A30in Devonthere remain several unimproved single carriageway sections which cause congestion, especially during summer months and at weekends. The A303 also passesthroughthe Stonehenge World Heritage Site andthe Cranborne Chase & West Wiltshire Downs and Blackdown Hills Areas of Outstanding Natural Beauty.
2.2 The corridoris made up of a mixture of single and dual carriageway all- purposetrunk road, with approximately 63% dual carriageway and 37%
single carriageway. Speedlimits vary between 40mph and 70mph. There are numerous at-grade and grade separatedjunctions and private property accesses alongthelength ofthe route.
2.3 Previous studies have proposed completingthe dualling ofthe route. Together withimprovementstothe A358 betweenIlminster and
Taunton,this would create a‘second strategic route’intothe South West in additiontothe M4/M5. The Government recognisestheimportance of the A303 corridorinterms ofits rolein providing accesstothe South West, facilitatingthe movement of goods and people, andits contribution tothe economic performance ofthe corridor.
2.4 The Departmentfor Transport andthe Highways Agency have worked closely withthe South Westlocal authorities. Thisincludedthe analysis and business cases for potentialinvestment.Recent work undertaken by a grouping oflocal authorities and Local Enterprise Partnerships
produced aninitial analysis and business caseforfutureimprovements tothe A303 corridor. This provided a useful starting pointforthis feasibility study.
3 . S tudy a ims and ob jec t ives
3.1 The aim ofthe study wastoidentifythe opportunities and understand the caseforfutureinvestment solutions onthe A303/A30/A358 corridor that are deliverable, affordable and offer valuefor money.
3.2 Interms of geographic scope,the study consideredthelength ofthe A303/A30 corridorfromthejunction betweenthe A303 and M3inthe east near Basingstoketothejunction betweenthe A30 andthe M5inthe west at Exeter, alength of 115 miles. The geographic scope ofthe study alsoincludedthe A358fromitsjunction withthe A303 atIlminstertoits junction withthe M5in Taunton, alength of 9 miles.
3.3 The A303 passesthrough Stonehenge World Heritage Site, so as part of the study,theimpactof any proposed work onthislandscape of
international heritage significance neededto be understood. The A303/A30 section also passesthrough boththe Cranborne Chase &
West Wiltshire Downs and Blackdown Hills Areas of Outstanding Natural Beauty.
Figure 1: The geographic scope of A303/A30/A358 feasibility study
3.4 The modal scope ofthe study was predominantly road-based but also consideredthe availability of rail servicesinthe area. The study
consideredthe details of performance and currentinvestment proposals fortheidentified partsofthe strategic road network, as well asthelocal authority road network, particularlythe A358 whichisthe responsibility of Somerset County Council.
3.5 The objectives ofthe A303/A30/A358 corridor study wereto:
•
• identify and assessthe case, deliverability andtiming of specific infrastructureinvestmentsthat address existingissuesand likely future problems onthe A303/A30/A358 corridor;
•
• understandthe balance of benefits andimpactsfrom potential
individualinvestment proposals and any additional benefits orimpacts from aninvestment on a corridor basis;
•
• evidence where possiblethe wider economic benefitsfromthe transportinvestmentinthe corridor;
•
• understandtheimpacts of potentialinvestmentinthe A303/A30/A358 corridor onthe performance of other road corridorsinthe South West region; and
•
• understandtheimpacts ofthe proposedinvestmentinthe
A303/A30/A358 corridor onthe resilience ofthe road network. 3.6 The studytook place from springto autumn 2014and was undertaken
bythe Highways Agency andits consultants. The study processfollowed thatinthe Departmentfor Transport’s guidance(WebTAG)for such studies and a stakeholder Reference Group wasformedto ensure effective externalinvolvement. This Reference Group acted as a sounding board and allowedthe views of stakeholdersto be captured and considered duringthe study process. The organisations represented onthe group arelistedin the Annex.
4 . Cu r ren t and fu tu re s i tua t ion
4.1 Thefirst part ofthe study involvedreviewingevidence and analysis from other relevant study worktoform a view astothe nature and scale of current andfuture performance onthe A303/A30/A358 corridor.It also established boththe availability of suitabletransport models andthe needto undertake additionaltransport modellingforthe study. 4.2 Analysis oftraffic data has shownthatthe corridoris usedfor many
differentjourney purposesincluding commuting,leisure, business and retail. The highesttrafficflows arefound atthe eastern and western extremities ofthe corridor withflows varying between 35,000 and 50,000 vehicles per day. Thelowestflows arefound onthe A303/A30 section throughthe Blackdown Hills, withflows varying between 13,000 and 15,000 vehicles per day. Many ofthe sectionsinthe middle ofthe corridor haveflows between 20,000 and 25,000 vehicles per day, and typical HGV proportions are 10% which, bearingin mindthe high variationinflow,indicates a relatively high proportion oflocal as well as longer distance HGVtraffic.
4.3 Trafficflows alongthe whole corridor are significantly affected duringthe summer months withincreases dueto holidaytraffic. Thelargest
observedincreaseis onthe A303/A30 sectionthroughthe Blackdown Hills where anincrease of upto 50%intraffic was observed, with other sectionstypically seeing anincrease ofthe order of 20% to 30%. 4.4 On certain sections ofthe routethetrafficflows can exceedthe design
capacityleadingto congestion, delay and unreliablejourneytimes. Many ofthe single carriageway sections ofthe route are over-capacity under normal conditions,includingthe Amesburyto Berwick Down sectionthat passesthroughthe Stonehenge World Heritage Site. Othersingle carriageway sections ofthe route are also over-capacity duringthe summer months.
4.5 The corridor wasfoundto have a comparable safety recordto other sections ofthe strategic road network. However, analysis ofthe safety data showedthatthe majority ofthetrafficincidents recorded alongthe corridor occurred onthe single carriageway sections ofthe route. 4.6 Railis byfarthe most significant alternative to road-basedtravel along
the A303/A30/A358 corridorasthere are limitedcoach and express bus operations. Although air routes exist,they are alsolimited, particularly withthe closure of Plymouth Airport and current limitedflight schedules to Newquay.
4.7 It cantake asubstantial period oftimeto get from Londonto Exeter and beyond by rail.2Thetimetakenfor a roadjourney on a typical weekday betweenthe centres of Exeter and Londonis either comparable or longerin duration3, especially during weekend and holiday peaks.
However,the vast majority of thosetravelling appearto need acar atthe destination end andtherefore drive.
4.8 Alack of convenient and efficient road-railtransfer and interchange facilities withinthe corridor also hampers modaltransfer or bi-modal travelfortrips withinthe corridor.
4.9 The SWARMMS study conductedin 2002 wasthelastto
comprehensively considerthe A303/A30/A358 corridorinits entirety including all modes and modaltransfer andtravel demand possibilities. Despite recommending a preferred strategythatfeatured significant upgrading of both rail and road provision between London and Exeter4, the SWARMMS study also concludedthat whilstthereis a degree of interaction between rail and road withinthe corridor,the extentto which they‘compete’forthe sametravellersisrelatively small.5
4.10 There are growth proposalsinthe Exeter, Taunton, Yeovil, Amesbury and Andover areas which mayimpact on corridorflows. Takentogether, the planned developmentsforthe South West amountto over 200,000 new homes and 150,000jobs by 2031,whichis estimatedtoincrease congestion alongthe route.
4.11 These specific growth proposals,together withgeneralforecast increasesintraffic alongthe corridor, meanthattheissues of
congestion, delay and safety onthe single carriageway sections are likelyto be exacerbated.
4.12 Duetothelength ofthe A303/A30/A358 corridor,the decision wastaken tofocusfurther stages ofthe study work onthose sections ofthe route that experiencethe worst conditionsinterms of congestion and delay, reliability ofjourneytimes and safety. These sections were:
•
• A303 between Amesbury and Berwick Down;
•
• A303 between Chicklade Bottom and Mere;
•
• A303 between Sparkford andIlchester;
•
• A303 between South Petherton and Southfields; and
•
• A303/A30 between Southfields and Honiton,including consideration of the A358.
2SWARMMS citedthefollowing: Exeter-Waterloo 3hrs 25mins via Yeovil and Exeter-Paddington via Taunton and Reading 2hrs 20mins. National Rail’sjourney planner confirms bothjourneytimes.
3SWARMMS cited 3hrs 15mins. Google maps confirmsthisjourneytime.
4Londonto South West and South Wales Multi-Modal Study, Corridor Plan: London–Exeter, Government Officeforthe South West, Halcrow, May 2002.
5Londonto South West and South Wales Multi-Modal Study, Corridor Plan: London–Exeter, Government Officeforthe South West, Halcrow, May 2002.
4.13 The data collection andidentified problems andissuesinformedthe definition of a set ofintervention-specific objectivesthat were usedto assess potential optionstoimprovethe route:
•
• Support economic growth: facilitate growthin employment and housingin keylocations and hotspots alongthe corridor;
•
• Capacity: reduce delay and queuesthat occur during peak hours and seasonaltimes ofthe year;
•
• Resilience: improvethe resilience ofthe route suchthatthe number ofincidents andthe effect of accidentsis reduced;
•
• Safety: reducethe number of collisions onthe A303/A358/A30 corridor;
•
• Connectivity: improvethe connectivity ofthe South Westtothe rest ofthe UK,to reduce peripherality andimprove business and growth prospects; and
•
• Environmental: avoid unacceptableimpacts onthe surrounding natural environment andlandscape and optimisethe environmental opportunities and mitigationthattheintervention could bring.
5 . Inves tmen t op t ions
5.1 Followingtheidentification of problems onthe route,the study reviewed previous work toidentifyinfrastructure proposalsthat could addressthe problems. A range of potentialinvestment proposals and combinations of proposals was considered,initially building on work doneto date on potential proposals, ratherthan completing afresh process of
identification ofinvestment proposals.
5.2 The study drew upon a range of related workinterm of studies or strategiesforthe A303 corridor,includingthe 2002 Londonto South West and South Wales Multi-Modal Study (SWARMMS) and Somerset County Council’s A303 CorridorImprovement Programme work. The study also captured details of potentialinvestment proposals emerging fromthefirst phase ofthe Highways Agency’s South West Peninsula Route Strategy which was publishedin April 20146.
5.3 The option generation processidentified aninitiallonglist of highway interventionsfor each section ofthe corridor. Thisranged from small- scale operationalinterventions such as reductionin speedlimits and right-handturn provisions,together withlarge-scaleinterventions such as dualling proposals and bypasses. The next stage wasthento usethe Department’s Early Assessment and Sifting Toolto qualitatively score and assess each option.
5.4 A small number of better performing options were thenidentified. These weretakenforwardfor more detailed assessment againstthe DfT's Option Assessment Framework, with evidence presented againstthe best practice Treasuryfive case model (the strategic, economic, financial,management and commercial cases):
•
• A303 between Amesbury and Berwick Down - Part on-line, part off-line dual carriageway withtunnel - Off-line duallingtothe north of existing route
•
• A303 between Chicklade Bottom and Mere - Combination of on-line and off-line widening
•
• A303 between Sparkford andIlchester - Combination of on-line and off-line widening
•
• A303 between South Petherton and Southfields - On-line dualling
6https://www.gov.uk/government/publications/route-based-strategies-evidence-reports
•
• A303/A30 between Southfields and Honiton,including the A358 - Improvements on A303/A30 between Honiton and Rawridge Hill,
Rawridge Hill and Stopgate Cross and Eagle Tavern and Broadway - Duallingthe A358
- Combination ofthetwo above
5.5 All options scored beneficially againstthe majority of strategic and objective goals, withthelarger-scale dualling options scoringthe highest. However,theselarger-scale optionstendedto scorelower on deliverability, particularlywhen considered against environmental factors. This wasduetothe extent of engineering works required and theimpactthatthis could have onthe surroundinglandscape and environment.
5.6 Based onthe assessment against DfT's Option Assessment Framework, all options were prioritisedfor more detailed work. Together withthe individual options above, an assessment ofthe caseforfull dualling of the route was alsotakenforwardforfurther development.
6 . Inves tmen t c ases
6.1 The affordability, valuefor money (VfM) and deliverability ofthe prioritised proposals were then assessed. The study usedthe
Department’stransport appraisal guidance and consideredthe benefits and business casesfor each ofthetransportinvestment proposals, as well asthe cumulative or additional benefits andimpactsfrom
investmentinthe corridor as a whole.
6.2 The appraisal conducted was appropriatetothe early stage of
development ofthe proposals and will bedeveloped furtherto ensure a full understanding oftheimpacts ofthe proposals and valuefor public money. An explanation ofthe way DfT assesses VfM can befoundinthe VfM note7.
Entire route options
6.3 The studylooked atthe costs, benefits andimpacts of dualling all remaining single carriageway sections ofthe A303 betweenitsjunction withthe M3inthe east andthe A358inthe west. This option included proposalsfor a 1.8 miletunnel asthe road passes Stonehenge, dualling of all remaining single carriageway sections ofthe A303 betweenthe M3 andthejunction withthe A358,plus grade-separation of several
junctions and duallingof the A358.
6.4 This proposal wasfoundto perform well againstthe objectives, asit will improve connectivity and accesstothe South West,improvingthe resilience ofthe strategic road networkinthe region and helping to promote economic growth.
6.5 This also provided a good strategicfitto Departmentfor Transport, Highways Agency, Local Authority and Local Enterprise Partnership objectives, and would help stimulate economic growthinthe area by providing a second dual carriagewaylinktothe South West.
6.6 However,this would have adverseimpacts on biodiversity and
landscape, particularly wherethe routeis off-line.Dualling would also affect the Cranborne Chase& West Wiltshire Downs Area of
Outstanding Beauty and would have adverseimpacts onlandscapein that area. Dualling ofthe entire route withtunnelling would have some beneficialimpacts on biodiversity andlandscapein other sections ofthe route,in particular alongthe Amesburythe Berwick Down section asthe route passes Stonehenge.
6.7 The caseforthis proposal suggests, atthis early stage of business case development, highto very high valuefor money.
7https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/255126/value-for-money- external.pdf
6.8 The modelling suggeststhatthe valuefor money of upgradestothe entire routeis higherthan we might expect when consideringthe schemesindividually. Thisis becauseindividual schemes, aslisted below, needto be consideredinthe context of theother route
improvements. Those which do not appearto offer valuefor money as stand-aloneinvestments may be worthwhile enhancements,once other parts ofthe route have been upgraded.
Amesburyto Berwick Down options
6.9 Interms ofthe Amesburyto Berwick Down section,the studylooked at the costs, benefits andimpacts ofthreeindividual options:
•
• Part on-line, part off-line dual carriageway with 1.6 miletunnel;
•
• Part on-line, part off-line dual carriageway with1.8 mile tunnel; and
•
• Off-line duallingtothe north oftheexisting route.
6.10 Each option alsoincluded a bypass of Winterbourne Stoke and grade separatedinterchanges at Countess Roundabout and theA360junction. 6.11 Toinformtheir position, English Heritage andthe National Trust
commissioned a piece of workto assesstheimpacts ofthe options on the Stonehenge World Heritage Site. The assessmentfoundthat atwin- boredtunnel of between 1.6 miles and 1.8 miles,if designed well, could have a beneficialimpact onthe Outstanding Universal Value ofthe Stonehenge World Heritage Site. This was based on removing the surface road and minimisingthe harmfulimpacts of anytunnel scheme whichlies withinthe boundaries ofthe World Heritage Site. The work alsofoundthatthe off-line dualling option would have alarge adverse impact onthe Outstanding Universal Value ofthe Stonehenge World Heritage Site.
6.12 Bothtunnel options werefoundto perform well againstthe objectives, as they willimprove connectivity and accesstothe South West,therefore improvingthe resilience ofthe strategic road networkinthe region and helpingto promote economic growth. Bothtunnel options also provide a good strategicfitto Department for Transport, Highways Agency, Local Authority and Local Enterprise Partnership objectives. These were aligned withthe aiminthe Stonehenge World Heritage Site
Management Plan 2009to reducetheimpacts ofintrusivefeatures on the Outstanding Universal Value ofthe Heritage Site,includingthe A3038.
6.13 The off-line duallingtothe north ofthe existing route performed well against some objectives, helpingtoimprovejourneytimes and
connectivity. However,itwould have an adverseimpact on biodiversity andthelandscape and historic environment ofthe World Heritage Site. 6.14 Takeninisolation,the 1.6 mile tunnel wasfoundto have a poortolow
benefitto cost ratio andthe 1.8 mile tunnel wasfoundto have a poor
World Heritage Site of atunnel option andthis needsto befactoredinto furtherconsiderations regarding valuefor money. Furthermore,this assessment does not considerinteractions with upgradesto other parts ofthe route, which may bringfurthertraveltime benefits.Therefore,the valuefor money ofthetunnel options remains uncertain atthis early stage of development and needsto be viewedinthis wider context.
6.15 The off-line dualling option wasfoundto have poorto mediumvaluefor moneytakinginto consideration boththe monetised assessment of traveltime savings and reliability andthe adverseimpact onthe World Heritage Site.
Chicklade Bottomto Mere options
6.16 Interms ofthe Chickladeto Mere options,the studylooked atthe costs, benefits andimpacts of a combination of on-line and off-line widening, which wouldinclude grade separatedjunctions and a bypass of the village of Chicklade.
6.17 This proposal wasfoundto perform well against some ofthe objectives, asit willimprove connectivity and accesstothe South West region, thereforeimprovingthe resilience ofthe strategic road networkinthe region and helpingto promote economic growth.It will also helpto reduce delay and congestion onthis section,leadingto a reductionin incidents.This option will however have adverseimpacts onthe landscape and environment ofthe Cranborne Chase& West Wiltshire Downs Area of Outstanding Natural Beauty and adverseimpactsin terms ofnoise emissions.
6.18 This option provides a good strategicfitto Departmentfor Transport, Highways Agency, Local Authority and Local Enterprise Partnership objectives and visions.
6.19 This proposal wasfoundto demonstrate poor valuefor money atthis stage.The assessment tookaccount of boththe monetised assessment oftraveltime savings and reliability andthe adverse environmental impact onthe Cranborne Chase& West Wiltshire Downs Area of Outstanding Natural Beauty.
SparkfordtoIlchester options
6.20 Interms ofthe SparkfordtoIlchester options,the studylooked atthe costs, benefits andimpacts of a combination of on-line and off-line widening,including grade separatedinterchanges.
6.21 This proposal wasfoundto perform well against some ofthe objectives, asit willimprove connectivity and accesstothe South West region, thereforeimprovingthe resilience ofthe strategic road networkinthe region and helpingto promote economic growthinthe region.It will also helpto reduce delay and congestion onthis section, alsoleadingto a reductioninincidents. This option will however have an adverseimpacts onlandscape and biodiversity wherethe route goes off-line.
6.22 This option also provides a good strategicfitto Departmentfor Transport, Highways Agency, Local Authority and Local Enterprise Partnership's ownobjectives and visions.
6.23 The assessment of this proposalatthis stage, suggests a highto very high valuefor money case.
South Pethertonto Southfields options
6.24 Interms ofthe South Pethertonto Southfields options,the studylooked atthe costs, benefits andimpacts of online duallingincluding bridge widening and a grade separatedinterchange at Hayes End.
6.25 This proposal wasfoundto perform well against some ofthe objectives, asit willimprove connectivity and accesstothe South West region, thereforeimprovingthe resilience ofthe strategic road networkinthe region and helpingto promote economic growthinthe region.It will also helpto reduce delay and congestion onthis section, alsoleadingto a reductioninincidents. This option will however have some adverse environmental impacts dueto anincreasein overall noise emissions. 6.26 This option also provides a good strategicfitto Departmentfor
Transport, Highways Agency, Local Authority and Local Enterprise Partnership objectives and visions.
6.27 The assessment ofthis proposal atthis stage,suggests a poortolow valuefor money case.
Southfieldsto Honiton options,including consideration ofthe A358
6.28 Interms of Southfieldsto Honiton options,the studylooked atthe costs, benefits andimpacts ofthreeindividual options:
•
• A303/A30improvements between Honiton and Broadway (Honitonto Rawridge Hill, Rawridge Hillto Stopgate Cross and Eagle Tavernto Broadway). Thisincludes part on-line, partoff-lineimprovementsto create overtaking opportunities,improvejunctions and bypassthe village of Monkton;
•
• Dualling ofthe A358 which willinclude grade-separatedinterchanges and a bypass south of Henlade; and
•
• Combination of both options above.
6.29 Both the A303/A30 andthe A358 options provide a good strategicfitto Departmentfor Transport, Highways Agency, Local Authority and Local Enterprise Partnership objectives and visions. Both were alsofoundto perform well againstthe objectives, asthey willimprove connectivity and accesstothe South West region,thereforeimprovingthe resilience of the strategic road networkinthe region and helpingto promote economic growthinthe region.
6.30 The A303/A30improvements passthroughthe Blackdown Hills Area of Outstanding Natural Beauty and werethereforefoundto have an
adverseimpact onlandscape and biodiversity. Althoughthe
improvements considered were notfull dualling proposals,they would
6.32 Atthisstage of assessment,the A303/A30improvement option was considered to havea lowto medium valuefor moneycase, takinginto consideration boththe monetised assessment oftraveltime savings and reliability andthe adverseimpact onthe Blackdown Hills Area of
Outstanding Natural Beauty. The A358 dualling option was considered to represent very high valuefor moneyand when bothimprovements were considered as a package they were also considered torepresent very high valuefor money.
Summary
6.33 Improvement optionsforfive different sections ofthe A303/A30/A358 corridor were developed. The valuefor money of each option was assessed, whichincluded consideration of boththeimpactsthat can be expressedin monetaryterms andthose which have been assessed qualitatively.
6.34 Atthis stage, the whole routeimprovement,including dualling ofthe A358 andthe provision of a 1.8 miletunnel asthe road passes
Stonehenge, wasfoundto representhighto very high valuefor money. The whole route option also hadthe greatestimpactinterms of
improvingjourneytimes and reliabilityfor usersand also has the biggest impactinterms ofencouragingeconomic growthinthe region duetothe factthatit would provide a second reliablestrategic routetothe South West.
6.35 There weretwo otherimprovements which werefoundto perform wellin terms of valuefor money:improvementstothe A358 andtothe A303 between Sparkford andIlchester. Other options,including proposalsfor Chickladeto Mere andforimprovementstothe A303/A30 between Southfields and Honiton werefoundto performless wellinterms of valuefor money, with adverseimpacts onthelandscape wherethe proposals would passthrough Areas of Outstanding Natural Beauty. 6.36 The value for money ofthetunnel optionat Stonehengeis uncertain due
tothefactthattheimpacts onthe World Heritage Site were assessed qualitatively. Both the National Trustand English Heritage consider that atwin-boredtunnel of somewhere between 1.6 miles and 1.8 miles,if designed well, could have a beneficialimpact onthe Outstanding Universal Value ofthe Stonehenge World Heritage Site.
7 . S tudy ou tcomes
7.1 Following completion ofthe study work and consideration ofthe potential investment options,theGovernment has committedtotakeforward an overallinvestment package of around £3.5 billion forthe sixfeasibility studies.
7.2 The needtotacklethe difficultissuesthat exist alongthis route iswell recognised,includingthe proximity of a congested roadtothe
Stonehenge World Heritage Site.The Government has made along- term commitment worth £2 billionto upgrade all remaining single- carriageway sections of A303 betweenthe M3 andthe A358to dual carriageway standardtogether with providing a dual carriagewaylink fromthe M5 at Tauntontothe A303. Weintendto startthis process with three majorimprovements which were announced as part ofthe Road Investment Strategyin December 2014. These will be developed
sensitively and with due care and consideration giventothe surrounding environment:
•
• A303 Amesbury to Berwick Down dualling –construction of a tunnel of atleast 1.8 mileslong asthe road passes Stonehenge and a bypassfor Winterbourne Stoketolinkthe existing dual carriageway section around Amesbury withthe dual carriageway at Berwick Down.
•
• A303 Sparkford toIlchester dualling –dualling ofthe 3 mile single carriageway section ofthe A303 between Sparkford andIlchester.
•
• A358 Taunton to Southfields dualling –creating a dual carriageway linkfromthe M5 at Tauntontothe A303.
7.3 We will also set asidefundingfor smaller-scaleimprovementstothe A303/A30 section between Southfields and Honiton. This willimprove safety andjourney qualityfor road users recognisingthatlarge scale improvements would be challenging giventhe protectedlandscape and topography surroundingthe route. Thisincludes some small-scale work inthe Blackdown Hills Area of Outstanding Natural Beauty which will take account ofthe environmental sensitivity ofthe area.
7.4 Fullimplementation ofthese proposals will run beyondthefirst Road Period, and weintendthat subsequent RoadInvestment Strategies will fundthe remainingimprovements.
7.5 These proposals will requirefurther work, engagement and consultation in orderto reach agreement onthe specific details ofthe proposals.Any schemes progressed will require completion ofthe necessary statutory
Figure 2: Outcomes from the A303/A30/A358 corridor feasibility study
Annex: Re fe rence G roup Membe rs
Local Highway and Planning Authorities: Devon County Council
Dorset County Council Hampshire County Council Plymouth City Council Somerset County Council Torbay Council
Wiltshire County Council Local Enterprise Partnerships: Cornwall andIsles of Scilly LEP Dorset LEP
Heart ofthe South West LEP Solent LEP
Swindon and Wiltshire LEP West of England LEP
Statutory Bodies: English Heritage Natural England Other organisations:
Blackdown Hills Area of Outstanding Natural Beauty Campaignfor Better Transport
Campaignto Protect Rural England Devon and Cornwall Business Council
International Council on Monuments and Sites National Trust
Somerset Chambers of Commerce Travel Watch South West
The Wildlife Trusts Members of Parliament: David Heath MP
John Glen MP
