Crossrail 2 Shafts
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Crossrail 2 shafts Crossrail 2 factsheet: Victoria station Shafts would be required along the tunnelled section of the proposed Crossrail 2 route to connect the tunnels to the surface and provide a safe and comfortable environment for passengers and staff Why would shafts be needed? What would a shaft look like? Shafts would connect the underground Crossrail 2 tunnels Most of the shaft would be underground with an above- with the surface. During everyday operations, the motion ground structure known as a ‘head-house’. This would of trains would push air out of the tunnels and pull air provide access to the shaft itself, the equipment within into them from the atmosphere. As the air pushed out is it and the tunnels below. A head-house is ideally located usually warmer than the air pulled in, the shafts would help directly above the shaft and tunnels, except in some cases to provide a more comfortable temperature for passengers where they can be located separately and connected by a and staff. short underground passage. A street-level entrance would provide access for the fire and rescue services, for the safe During periods of disturbed service, when trains could be evacuation of passengers in an emergency as well as for held in Crossrail 2’s tunnels for an extended period of time, maintenance. Direct access to the head-house is required the shaft’s ventilation system would deliver cooler air from for emergency and maintenance vehicles. the atmosphere to the tunnels and to stationary trains. At stations the head-house would typically be integrated In the unlikely event of a fire, the shafts would control with the overall station structure. At locations between smoke, provide access for the fire and rescue services stations the head-house would be separate. At this early and provide a safe evacuation route for passengers. stage of Crossrail 2 design, we expect a typical head- house to occupy an area of around 25 metres by 25 metres and to be at least two storeys high – although the size Where are shafts required? of each head-house would be influenced by local factors Shafts would be required at both ends of each including the depth of the tunnels and the height of underground Crossrail 2 station. Where possible, these surrounding buildings at each site. Further design work would be constructed within the overall station structure. would be required to determine our requirements at each individual location. Shafts would also be required at locations between underground Crossrail 2 stations where operational and As the Crossrail 2 scheme develops further, we would safety requirements determine they are needed. engage with the relevant local authority, interested stakeholders and local communities to inform the designs for each head-house. The examples overleaf illustrate some of the different ways in which head-houses can be integrated into their surroundings. G2 Selecting shaft locations Minimising our impact The locations of station shafts would form part of the Crossrail 2 would require shafts in the following Crossrail 2 shafts would be designed to avoid any All our contractors would have to adhere to a Code overall design for each station. proposed locations: noticeable impact on background noise levels or air of Construction Practice, which would be developed quality from their operation. together with local authorities. This would set out • Downhills Recreation Ground A separate process is undertaken to inform the locations Crossing the Capital, Connecting the UK requirements for considerate construction practices that of shafts in between stations and in doing so a range of (S2: Seven Sisters to New Southgate Route Options) Proposals for the scheme are still at theTYPICAL early stages of use theVENTIL latest techniques to reduceATION noise and disruption SHAFT factors would be considered. These include: design. Feedback from this and future consultations, both for surface and underground works. • Stamford Hill area (featured within this factsheet) together with further design and engineering work, will • Whether a site can provide an area of at • Shoreditch Park area (featured within this factsheet) refine the proposals ahead of seeking permission to build As part of our Environmental Statement, a full assessment least 3,000metres2 the new railway. of the potential impacts of construction and operation • Victoria Coach Station (S9: Victoria station) of the scheme will be documented along with proposed • Existing land use and community impacts methods to minimise impacts where required. These • Westbridge Road (featured within this factsheet) proposals would then form commitments as part of the • Environmental and heritage impacts application for planning consent. • Wandsworth Common (Honeywell Road) • Site suitability for construction (S12: Wimbledon to Clapham Junction) • Site suitability for operational and safety requirements • Springfield (S12: Wimbledon to Clapham Junction) • Potential for reinstatement of the site • Weir Road (S12: Wimbledon to Clapham Junction) Diagram to illustrate how a shaft operates warm air from tunnels pushed out into air pulled in atmosphere by fans by shaft ventilation ventilation outlet shaft can be incorporated within a building grille ing tunnel crossrail runn ventilation outlet can be a freestanding structure mechanical equipment rooms ventilation shaft emergency train stationary in tunnel access stairs el ing tunn ail runn crossr emergency access passage to tunnels Mile End In the event of a fire emergency affecting a trainKennington the Parkfans will Detail layout Bond Street ‘Green design’ be used to control and extract smoke to enableConservation passenger Area Incorporated into London Borough of Gibson Square London Borough of station box The layout of eachTower Hamlets evacuationHeritage design along the trackside walkway. TheSouthwark tunnel Northern Crossrail Line 1 intermediate ventilationCrossrail Line shaft 1 ventilationLondon Borough system will help to ensure that theline underg extension round (post-construction, (post-construction, fresh air pulled of Islington (post-construction, will vary to reflect the into shaft by fans environment remains comfortable and safe for passengers at visualisation) visualisation) Victoria line visualisation) constraints imposed by all times. different locations but each Method of operation will contain: mechanical equipment attenuator rooms When 'forced' ventilation is required, two ventilation shafts - three electric fans - all to reduce noise will work in conjunction with each other. One will push fresh reversible to enable the fan access stair for emergency services air into the tunnel and the other will pull exhaust air into the to push or pull air as atmosphere. In this way a steady airflow can be set up in the required. Two fans will attenuator to Crossrail reduce noise tunnels. operate at any given time running tunnel at tunnel level Fans will either: with one on standby. - blow cooling air over a stationary train. damper open - ventilation control valves - extract smoke from the tunnel in the event of a fire. damper closed (dampers) at tunnel level to escape walkways direct air into or out of the fresh air pushed into tunnel smoke pulled out correct tunnel. Section Through - baffles (attenuators) to Ventilation Shaft minimise noise from fan motors. direction of passenger escape - an access stair to the separating tunnels for use by the wall emergency services. 3 fans - equipment necessary to (1 standby) Fans Operating to Control Smoke in the operate the fans will be Event of a Fire Emergency housed in a structure (usually underground) emergency access stair Location incorporated within all attached to the shaft and intermediate ventilation shafts Ventilation shafts will be provided at all Crossrail underground will be accessed from stations. Intermediate ventilation shafts will be provided at 1i0601-c1v00-50001 street level. specific intervals between stations in order to ensure an Plan of Shaft adequate airflow. Manor Seven Chadwell Gidea Heathrow Hayes and Harlington Ealing Broadway Stratford Park Kings Heath Park Brentwood Tottenham Liverpool Forest Ilford Goodmayes Romford Harold Shenfield Paddington Court Road Street Gate Wood Hampton Strawberry Bond Street Farringdon Whitechapel Custom Slade Stone Wick Hill Richmond Gunnersbury House Belvedere Green Crossing Swanscombe Kingston Teddington Twickenham Kew Turnham Isle of Abbey Erith Dartford Greenhithe Ebbsfleet Gardens Green Dogs Wood Crossrail BATTERSEA BRIDGE ROAD D A O R H C R U H C E A 85 R S BOLINGBROKE WALK HENTY CLOSE T E AT B Westbridge Road 65 Games Court Westbridge Primary School Why is a shaft needed in this location? The proposal To enable Crossrail 2 to operate safely, we would need A single worksite would be required to build the shaft, a shaft midway between Clapham Junction and King’s and a typical shaft would take Montevetroapproximately five years BOLINGBROKE WALK 109 Road Chelsea stations. The shaft would provide tunnel to complete. Activity on site would fluctuate during this ventilation, access for the fire and rescue services and a period. Once the site has been cleared and prepared, the H Y D E L A N E safe evacuation route for passengers in the event of an major construction work to dig out the shaft would usually The Bridge emergency. be complete within two years. 52 2 On completion of the works at each site, an above- Our current preferred site is within the Surrey Lane Estate WESTBRIDGE ROAD at Westbridge Road. This has been selected to avoid ground structure known as a ‘head-house’ would remain. Somerset School taking residential land, and the site has already been The head-house would provide access to the shaft, the RANDALL CLOSE SUNBURY LANEand Nursery safeguarded for Crossrail 2. equipment within it and the tunnels below. It would also 4 allow air to be drawn into and out of the tunnel ventilation system. At this early stage of Crossrail 2’s design, we expect a typical head-house to be at least two storeys Somerset high and to occupy an area of around 25m by 25m. As the scheme develops further, we would engage with the local Estate authority, interested stakeholders and local communities 24 to inform the designs for each head-house.