{{Use dmy dates|date=July 2020}} {{Use British English|date=July 2020}} {{Infobox bridge | name = Wendover Dean Viaduct | image = | caption = | coordinates = {{Coord|51.7371|-0.7228|display=inline,title|region:GB_type:landmark}} | os_grid_reference = SP882050 | carries = [[High Speed 2]] | crosses = | locale = [[Wendover]] | official_name = | maint = | heritage = | owner = | operator = | traffic = | notrack = 2 | gauge = {{Track gauge|Standard gauge}} | electrification = {{25 kV 50 Hz AC}} | architect = Moxon Architects | designer = ASC ([[Arcadis]], [[Société d'études techniques et économiques|Setec]] and [[COWI A/S|COWI]]) | length = {{convert|450|m|abbr=on}}<ref name = "compressbooklet 2018"/> | width = {{convert|14|m|abbr=on}} | height = {{convert|18|m|abbr=on}} | number_spans = 10 | builder = EKFB ([[Eiffage]], [[Kier Group|Kier]], [[Ferrovial]], [[BAM Nuttall]]) | fabricator = | open = | extra = }} [[File:HS2 Wendover Dean Viaduct, construction Feb 2026.jpg|thumb|HS2 Wendover Dean Viaduct, construction Feb 2026]] [[File:HS2 Wendover Dean Viaduct, North and compound Feb 2026.jpg|thumb|HS2 Wendover Dean Viaduct, North and compound Feb 2026.]] [[File:HS2 Wendover Dean Viaduct, South embankment costruction Feb 2026.jpg|thumb|HS2 Wendover Dean Viaduct, South embankment construction Feb 2026.]] The '''Wendover Dean Viaduct''' is a [[railway viaduct]] currently under construction that will carry the [[High Speed 2]] (HS2) railway line across farmland between [[Wendover]] and [[Great Missenden]], [[Buckinghamshire]], England.
Approval for the viaduct's construction was issued in 2017 via the [[High Speed Rail (London - West Midlands) Act 2017]]; its design was publicly revealed two years later. In June 2021, [[Buckinghamshire Council]] also approved plans for the viaduct. Design revisions centred around improving its aesthetics and minimising its impact on the countryside. Construction of the main deck took place between late 2021 and 2024, although high speed trains will not traverse the structure until several years after this point.
==History== Authorisation to construct the Wendover Dean Viaduct was granted, along with the rest of the first phase of HS2, by the [[High Speed Rail (London - West Midlands) Act 2017]].<ref>{{cite web |last1=Burnett |first1=Tom|date=10 June 2021 |title=HS2 - Wendover Dean Viaduct is approved but Bucks Council remains 'fundamentally opposed' |url=https://www.buckinghamshirelive.com/news/buckinghamshire-news/hs2-wendover-dean-viaduct-approved-5514195 |access-date=20 July 2021 |publisher=BuckinghamshireLive}}</ref> The near-finalised designs of both the Wendover Dean Viaduct and the neighbouring Small Dean Viaduct was revealed to the public on 1 November 2019. It was produced by the ASC [[joint venture]] between [[Arcadis]], [[Société d'études techniques et économiques|Setec]], [[COWI A/S|COWI]], and Moxon Architects.<ref name="reveal 2019">{{cite web |title=AJ exclusive: Moxon reveals designs for 'sibling' HS2 viaducts |url=https://www.architectsjournal.co.uk/news/aj-exclusive-moxon-reveals-designs-for-sibling-hs2-viaducts |publisher=Architects' Journal |first = Richard |last = Waite |access-date=20 July 2021 |date=1 November 2019}}</ref><ref name = "innovative index2021"/>
The contractor appointed to construct the viaduct is the EKFB [[consortium]], comprising [[Eiffage]], [[Kier Group|Kier]], [[Ferrovial]] and [[BAM Nuttall]]; the viaduct is to be one of the most substantial individual civil engineering works along the {{convert|80|km|abbr=in}} section between the [[Chiltern tunnel]] and Long Itchington Wood that EKFB is to build.<ref name = "innovative index2021"/> In late 2019, it was stated that its construction was set to commence during 2021, and the viaduct's completion was scheduled to occur during 2024.<ref name="reveal 2019"/>
On 10 June 2021, [[Buckinghamshire Council]] issued its formal approval of the submitted plans for the viaduct, despite its official position of opposing HS2 in general; Councillor Peter Martin, Buckinghamshire Council’s Deputy Cabinet Member for HS2 observed that planning permission had already been granted irrespectively under the High Speed Rail act in 2017.<ref name = "Buckingham approval2021">{{Cite web |date=10 June 2021 |title=Game not over for Wendover Dean Viaduct |url=https://www.buckinghamshire.gov.uk/news/game-not-over-for-wendover-dean-viaduct/ |access-date=20 July 2021 |website=Buckinghamshire Council |language=en-GB}}</ref> Prior to its approval, the council held talks with [[High Speed 2|HS2 Ltd]], during which the latter gave assurances related to the noise levels that will be produced by the operational viaduct, along with numerous refinements to the design to minimise its impact upon the local community.<ref name = "Buckingham approval2021"/>
==Design== The viaduct is to be built to the east of the [[A413 road]], between the settlements of [[Wendover]] and [[Great Missenden]], Buckinghamshire. Possessing an approximate length of {{Convert|450|m|abbr=on}}, it will cross above Durham Farm, a portion of Bowood Lane (which is to be partially realigned) and a private access road to Upper Wendover Dean Farm. The structure has a total of ten spans,<ref name = "compressbooklet 2018">{{cite web |title=Wendover Dean and Small Dean Viaducts and Green Tunnel South Portal Engagement Event |url=https://s3-eu-west-1.amazonaws.com/commonplace-customer-files/hs2inbucksandoxfordshire/Wendover%20Engagement%20Booklet_Final-compressed.pdf |publisher=High Speed 2 |access-date=20 July 2021 |date=September 2018}}</ref> which carry a deck consisting of two separate layers of [[reinforced concrete]] along with a pair of steel [[girder]]s. This double composite design has been claimed by the architect firm to be the first use of such an approach in Britain, although such techniques have been used before for France's [[TGV]] high speed network.<ref name = "innovative index2021"/><ref>{{cite web |url = https://www.newcivilengineer.com/the-future-of/future-of-bridges-hs2s-french-inspiration-for-chilterns-viaducts-13-11-2020/ |title = Future of Bridges: HS2's French inspiration for Chilterns viaducts |publisher = newcivilengineer.com |first = Greg |last = Pitcher |date = 13 November 2020}}</ref><ref>{{cite web |title=Package 2 Wendover Dean - Wendover Dean Viaduct and Associated Earthworks |url=https://publicaccess.aylesburyvaledc.gov.uk/online-applications/files/194062B38FE2417BAA702B4C0A1E8065/pdf/21_00860_HS2-WRITTEN_STATEMENT-2236279.pdf |website=Aylesbury Vale DC - Planning Permission}}</ref> A total of 1,400{{nbsp}}tonnes of [[weathering steel]] will be used, featuring an intentionally dark russet finish for a pleasing visual effect, reportedly making the structure appear to be thinner.<ref name = "construct inquirer2021">{{cite web |url = https://www.constructionenquirer.com/2021/07/20/new-hs2-viaduct-design-to-cut-carbon/ |title = New HS2 viaduct design to halve carbon emissions |publisher = constructionenquirer.com |first = Aaron |last = Morby |date = 20 July 2021}}</ref> The beams will be manufactured and installed by Eiffage Métal.<ref name=":0" />
The structure has been designed with a highly sleek design, reducing weight, material, and cost alike wherever reasonable to do so. The design team also sought this sleek approach for its visual properties, aiming to minimise its obtrusiveness upon the neighbouring countryside.<ref name = "innovative index2021"/> Following discussions with Buckinghamshire Council during the planning stages, several minor revisions to enhance the viaduct's aesthetic qualities, amongst other attributes, were made. These include the adoption of a textured exterior for neighbouring barriers.<ref name = "Buckingham approval2021"/> The viaduct's supports were one area of particular refinement, changes were made with the purpose of minimising its long term land usage as well as hedgerow loss.<ref name = "Buckingham approval2021"/> These supporting piers will vary in height across the length of the structure, the tallest of which will be {{Convert|14|m|abbr=on}}.<ref name = "innovative index2021">{{Cite web |date=20 July 2021 |title=Innovative design for Chilterns viaduct |url=https://www.theconstructionindex.co.uk/news/view/innovative-design-for-chilterns-viaduct |access-date=20 July 2021 |website=The Construction Index |language=en}}</ref> The piers will be pre-cast offsite in sections before being transported to their final locations via road vehicles.<ref name = "innovative index2021"/>
== Construction == Foundation laying work started in July 2022.<ref name=":0">{{Cite web |date=7 July 2022 |title=Wendover Dean Viaduct |url=https://www.hs2.org.uk/building-hs2/viaducts-and-bridges/wendover-dean-viaduct/ |access-date=7 July 2022 |website=High Speed 2}}</ref>
Following creation of the viaduct concrete piers, the deck was assembled and slid out over the piers in three stages to cover the overall {{convert|450|m|abbr=on}} length:
* First {{convert|90|m|abbr=on}} in January 2024<ref name=":1">{{Cite web |date=11 January 2024 |title=HS2 begins epic year-long, half-kilometre viaduct deck slide |url=https://www.hs2.org.uk/building-hs2/viaducts-and-bridges/wendover-dean-viaduct/ |access-date=11 May 2024 |website=High Speed 2}}</ref> * Next {{convert|180|m|abbr=on}} in May 2024<ref name=":2">{{Cite web |date=10 May 2024 |title=HS2 completes 3,130 tonne second Wendover Dean Viaduct deck slide | url=https://mediacentre.hs2.org.uk/news/timelapse-hs2-completes-3130-tonne-second-wendover-dean-viaduct-deck-slide |access-date=13 May 2024 |website=High Speed 2}}</ref> * Final 180{{nbsp}}m in August 2024<ref name=":3">{{Cite web |date=12 Aug 2024 |title=New Timelapse: HS2 completes epic 8 month Wendover Dean Viaduct deck slide | url=https://mediacentre.hs2.org.uk/news/new-timelapse-hs2-completes-epic-8-month-wendover-dean-viaduct-deck-slide |access-date=12 Aug 2024 |website=High Speed 2}}</ref>
==References== {{reflist}}
==External links== * [https://moxonarchitects.com/project/607-wendover-dean-viaduct/ Wendover Dean Viaduct] at Moxon Architects
{{High Speed 2 articles}}
[[Category:High Speed 2]] [[Category:Railway viaducts in Buckinghamshire]]