24/7 Freephone Community Helpline 08081 434 434 Thame Valley Viaduct Engagement Event February 2020 1MC06-CEK-IN-PRE-CS04_CL19-000001 1 2 24/7 Freephone Community Helpline 08081 434 434 Introduction High Speed Two (HS2) is the new high speed railway for Britain. Welcome to the HS2 and Eiffage Kier engagement event for the design of the Thame Valley Viaduct. This structure is known as a ‘key design element’, and in this booklet we will share our current designs with you to keep you informed of progress. HS2 – Our part in the bigger picture Who is Eiffage Kier? HS2 is a new high speed railway that will form the Eiffage Kier is a Joint Venture between the two major backbone of Britain’s transport network. It will civil engineering and construction companies, Eiffage connect eight of Britain’s ten largest cities and their and Kier. regions. Faster, easier and more reliable travel will Eiffage is a French civil engineering company that put more opportunities within reach for millions of employs over 70,400 people worldwide, with large people for work, business and leisure. scale projects across the globe including Canada, By increasing rail capacity, HS2 will free up space South Africa, Japan, and across Europe. Kier, the on existing lines for more commuter, regional and second largest construction company in the UK, freight services. This will relieve overcrowding has 90 years of experience in a range of specialities and improve reliability for millions of people using including infrastructure and civil engineering, Britain’s railways. housebuilding and land development. Read more about HS2 at www.hs2.org.uk Both partners bring specialist expertise in the design, Eiffage Kier is proud to have been appointed by construction, operation, financing and maintenance HS2 Ltd to deliver an 80km section of the new high of railway networks, including the construction of one speed rail link between the Chiltern Tunnel and Long of Europe’s latest high speed rail projects. Itchington Wood, with a planned completion date of We are committed to improving lives, communities 2025. and the engineering and construction industry by Along with this booklet there is a questionnaire providing sustained employment opportunities and asking for your thoughts and opinions on what being a good neighbour, protecting the environment matters most to you about the design and and the places we work. Our inclusive culture ensures construction of the railway in your area. Please return that our collaborative and innovative solutions this questionnaire by Saturday 29 February 2020 via provide exceptional value for money. freepost to ‘Freepost Eiffage Kier JV’. If you have any questions, please call the HS2 helpdesk on 08081 434434 where someone will be happy to help. 3 Context What are Key Design Elements? Where will the viaduct be? Key design elements are structures along the The Thame Valley Viaduct is located within the route that are recognised by HS2 to be important. Northern Vale. The viaduct crosses the low-lying This could be due to their size, their proximity to Thame Valley, approximately 350 metres to the stakeholders or their location within sensitive areas. south-west of the Rabans Lane Industrial area on the western periphery of Aylesbury. The viaduct The Thame Valley Viaduct is considered a key design is partially visible from Public Rights of Way to the element because it is close to a local residential area south-west. Other than that, the viaduct is obscured and the community interest around the River Thame by a combination of gentle folds in the landscape and corridor. existing hedgerows and trees. The design for this structure has been developed with consideration for the technical and structural requirements as well as the impact on their surroundings. This has involved reviews with Aylesbury Vale District Council and feedback from the HS2 Independent Design Panel. Artist’s Impression of the Thame Valley Viaduct landscape The location of the Thame Valley Viaduct within the surrounding towns and villages. The viaduct is shown in red, the route of HS2 is shown in green and yellow and the Public Rights of Way are shown as green dots. 4 24/7 Freephone Community Helpline 08081 434 434 Engagement and Initial Design Through our programme of local engagement, and meetings with residents, we understand some of the local concerns. We will use this understanding to take reasonable steps to address any issues you raise and continually look to lessen the impact of the project. It is our intention to inform, involve and respond to you during the design period. As a key design element, this structure is also subject to review by the independent HS2 Design Panel of architects, engineers and landscape architects. Their role is to act as a critical friend to ensure the designs meet the aspirations of the HS2 Design Vision. We continue to engage with the panel during the development of our designs. Artist’s impression of the Thame Valley Viaduct from the side A map showing the location of the viaduct across the River Thame and its floodplain 5 What is a viaduct? A viaduct is a type of bridge, made up of multiple spans and connecting two points of terrain. On this project they will carry the high speed railway and will cross valleys, rivers, roads and flood plains. During the construction of the first railway networks in the 19th Century, bricks were used by Victorian engineers for building viaducts as these were the materials readily available. These brick-arched viaducts were capable of carrying the Victorian trains and followed the landscape’s natural curves. Differences between gravity loads on Victorian and contemporary Modern high speed trains travel at around four viaducts times the speed of Victorian trains so they require a flatter, straighter track, passing over and under the natural landscape. Modern viaducts are required to cope with the large longitudinal forces that occur due to braking and traction of high speed trains; they require stiff and strong supports to transfer the braking load forces from the train, which can be as much as a 770 tonnes load, to the foundations. In keeping with HS2’s Design Principles, viaducts along the route must be designed sustainably, minimising maintenance and materials used, and be considerate to the area where they are being constructed while meeting the technical requirements of the railway. Impression of the Thame Valley Viaduct piers Artist’s impression of the Thame Valley Viaduct from a raised side view, showing the piers and spans 6 24/7 Freephone Community Helpline 08081 434 434 Thame Valley Viaduct Landscape and Context Landscape Design The Thame Valley Viaduct is located in the low With this in mind, our plan for the landscape design lying Northern Vale to the north-west of Aylesbury. is to reinforce the landscape features associated It travels across the River Thame within a broad, with the natural floodplain and to maximise the shallow floodplain, which cannot be accessed by the opportunities for habitat connectivity under the public. The floodplain is typically made up of grazing viaduct. This includes the establishment of a mixed farmland, indicated by ditches and gappy field wetland landscape comprising flood plain pasture, hedgerows with occasional trees. The course of the managed wetland habitat, grassland scattered River Thame is defined by scattered areas of wetland among areas of woodland, wetland vegetation of vegetation and broken tree lines. black poplar and willow, open pools and reed lined marshland. Beyond the floodplain the surface of the land begins to gently rise and fall with arable farmland being As the viaduct is very low in the landscape, there the dominant land use. The openness and limited will be low levels of natural light reaching under the variation in the geography of the area provides central part of the structure. We have proposed a a strong visual relationship with the higher, rural series of pools and swales and associated reed bed ground outside the Northern Vale to the west and to make the most of the space. Opportunities for settlement to the east. ecology features such as otter dens and bird nesting habitat are also being considered to make the most of the ecology diversity under the viaduct, while respecting the need for the structure to be regularly maintained in a safe manner. View of the Thame Valley Viaduct in its setting Although the location is not accessible, it is visible in mid-distance views from Public Rights of Way networks to the south-west of the structure, including several publicised regional trails such as the Thame Valley Walk and Midshires Way. In many of these views the River Thame is set within higher An isometric drawing of the viaduct ground to the north, with the tree-capped Whaddon Hill being a local landmark, and to the east by tree lines and structures at the Aylesbury urban edge. 7 Design Considerations The Thame Valley Viaduct has been conceived as a minimalist elevated causeway passing over the River Thame floodplain - minimising impact on farmland and the adjoining wetland meadow landscape. Composition Approach The vertical alignment of the route provides For the structure design, we have taken care to notable advantages to the design of the viaduct. simplify the profile of the deck spans as much as The structure will be low slung, with the average possible while joining the deck and pier connection. underside level approximately two metres above the This breaks up the length of the viaduct into subtle ground. and identifiable individual spans. These resemble the individual arches on a traditional, brick-built Victorian The subtle rise and fall of the current geography in viaduct. the surrounding area will have a masking effect to the viaduct.