Draft:Heathrow Express tunnel collapse
 | Draft article not currently submitted for review.
This is a draft Articles for creation (AfC) submission. It is not currently pending review. While there are no deadlines, abandoned drafts may be deleted after six months. To edit the draft click on the "Edit" tab at the top of the window. To be accepted, a draft should:
It is strongly discouraged to write about yourself, your business or employer. If you do so, you must declare it. Where to get help
How to improve a draft
You can also browse Wikipedia:Featured articles and Wikipedia:Good articles to find examples of Wikipedia's best writing on topics similar to your proposed article. Improving your odds of a speedy review To improve your odds of a faster review, tag your draft with relevant WikiProject tags using the button below. This will let reviewers know a new draft has been submitted in their area of interest. For instance, if you wrote about a female astronomer, you would want to add the Biography, Astronomy, and Women scientists tags. Editor resources
Last edited by The Navigators (talk | contribs) 25 days ago. (Update) |
 Photograph of the ground above following the collapse | |
| Date | October 20–21, 1994 |
|---|---|
| Type | Tunnel collapse |
| Deaths | 0 |
| Inquest | Heathrow Report |
Background
[edit]Following British Rail's privitisation in 1993, BAA took over the project, with Railtrack retaining responsibility for the new junction on the Great Western Main Line and the tracks.[1] The tunnel itself would consist of a two track cut-and-cover tunnel between the railway junction with the main line to the north side of the M4 motorway, transitioning to a twin-bore tunnel until it reached the Central Terminal Area, consisting of Terminals 1, 2 & 3.[1] A single bore tunnel continues on to Terminal 4, crossing under the cargo terminal and south runway.[1][2] Initial drawings early in the project's life planned on using tunnel boring machines for the tunnels carrying the rail lines, with the stations being constructed using tunneling shields and segmented linings.[1]
The use of the New Austrian tunneling method (NATM) was suggested in 1989 by advisors to BAA, with this method being used for station construction.[1]
Project
[edit]Collapse
[edit]A catastrophic collapse occurred at approximately 01:15 on 21 October 1994, in the area of the down-line platform tunnel, southeast of the Fuel Depot Shaft[3]
Timeline
[edit]Thursday, 20 October 1994
| |
|---|---|
| 19.00 | Start of Central Tunnel Area night shift, consisting of three crews. |
| Work started | |
| Example | |
| Example | |
| Example | |
| Example | |
| Around 20.30~21.00 | A piece of shotcrete fell from the face of the dwon-line platform tunnel 'north'. |
| Around 22.30 | Example |
| Example | Example |
| Example | Example |
Friday, 21 October 1994
| |
| Around 00.15 | Section engineer, a leading miner and the pit boss inspected entire concourse tunnel for cracks. They discovered recent repairs badly deformed. |
| Around 00.30 | Pit boss orders some miners to leave concourse tunnel. Remaining workers continued a shotcrete repair work continued at ch. 24 |
| Other miners were concluding shotcrete work in the down-line tunnel 'north' | |
| The site agent, tunnel superintendent and section agent arrived. Geoconsult's site engineer and the 'NATM engineer' arrived shortly after them. | |
| Around 00.30-00.45 | Cracking in central wall of the up-line had worsened. Down-line side gallery had extensive damage from horizontal cracking and surface shotcrete was spalling. |
| The crown had fractured longitudinally at the tunnel face and the failure was progressing along the tunnel | |
| Site agent, section agent and tunnel superintendent entered tunnels and inspected them. Miners had gathered near the base of the fuel depot shaft. The tunnel superintendent ordered a lone worker still applying shotcrete to leave the concourse tunnel. | |
| A miner observed dust rising from the invert of the concourse tunnel, indicating movement was occurring. | |
| Around 00.45 | Further cracking occurred within the tunnels. Spalling continued with it spotted around 5 metres (16 ft) into the concourse tunnel. |
| Site agent and tunnel superintendent, and separately Geoconsult's site engineer realized the situation was irretrievable. The site agent ordered a full evacuation of the tunnel. | |
| Workers were mustered at the base of the fuel depot shaft, and exited the tunnel in two groups via the passenger hoist. | |
| Around 00.50 | Upon reaching the surface, staff were instructed to muster in the site canteen, a portable building situated above the course tunnel, and the route to reach from the fuel depot shaft involved crossing above the down-line platform tunnel 'north'. |
| The second group felt ground movement, as they walked to toward the site canteen and Camborne House. | |
| Around 00.55 | Pit boss orders an evacuation of the entire site. The site canteen began to tilt. |
| Around 01.15 | A rapid catastrophic failure occurred in the tunnel system, originating from the down-line platform tunnel north. The initial length of the concourse tunnel also collapsed. |
Subsequent Collapses
[edit]On Saturday, 22 October, the up-line platform tunnel suffered a collapse, northeast of the Fuel Depot Shaft.[3][4] The following day, 23 October, a third collapse occurred, this one directly under the northern end of Camborne House, inflicting significant damage on both Camborne House and Camborne House Extension. Both buildings would be deemed total losses and later demolished.[3][4][5]
Response
[edit]In the aftermath of the collapse, Balfour Beatty staff contacted 999 to summon London Fire Brigade to the scene. London Fire Brigade contacted Heathrow Airport Fire & Rescue Service, who would notify Heathrow Operations Center at 01:21. The initial reports however did not accurately explain what occurred, and only when the BAA duty manager would arrive at the scene a couple of minutes did the scope of the disaster become known to Heathrow Airport staff.[6] It was only at this point that London Underground was informed of the situation.[6]
The area around the scene, outside the Fuel Depot Site was not closed and evacuated, such as car parks 1A and 3, pedestrian subways and roads around the site.[6]
London Underground decided to keep Piccadilly line closed around 03:56.[6]
Impact
[edit]Airport operations suffered significant disruptions due to the closures of roadways near to the collapse area and the closure of the Piccadilly Line.[7][8]
Car park 3 was closed in the event of further subsidence, removing 1,300 vehicle parking spaces from the airport's capacity.[8]
Passengers on the Underground were disembarked at Hatton Cross, with London Underground implementing a bus shuttle to Heathrow from there.[7] By 23 October, the closure was limited to Heathrow Terminal 4 tube station, impacting approximately 6,000 passengers daily.[9] Passengers bound for Terminal 4 continued to disembark at Hatton Cross and use a shuttle bus to the terminal.[10]
Airport operations suffered significant disruptions due to road closures, and the closure of subway links to Terminal 3.[4] Road closures caused a five mile long traffic jam, impacting the A4 and A312 near the airport. Traffic backups on the M4 airport-spur reached the main M4 motorway.
Compounding the issues was the closure of the Underground service to Terminal 4, due to the Underground line passing over the top a Heathrow Express tunnel, and within 18 feet (5.5 m) of Heathrow Express tunnel where the collapses occurred. The Underground closures lasted until
The additional work caused by the collapse and the Heathrow Express Rail Link opening was delayed until June 1998.[11]
Investigation
[edit]At the time of the collapse, other tunnel projects across London were using the NATM process, which all suspended work as a precaution. The Health and Safety Executive requested the suspensions remain in place until projects could prove they could continue safely.[12] The Health and Safety Commission requested the Health and Safety Executive conduct a two-part investigation, with the first considering if NATM tunnel process was safe in the United Kingdom, and second the specific causes of the Heathrow tunnel collapse.[13][12]
On 9 May 1996, HSE published the report into 'part one' of their investigation, Safety of New Austrian Tunnelling Method (NATM) Tunnels. This report considered the history of the NATM process and specific issues raised by geology specific to the United Kingdom, such as London clay.[13] The report ultimately concluded that while NATM tunnels are complex from an engineering perspective, and require careful oversight in the planning, design and construction to ensure a successful tunnel project with minimal adverse risk to workers or the public, that safe construction of NATM tunnels was possible.[14] HSE also determined that no legislation specific to NATM tunnel construction was needed and that a tunnel built with a NATM lining once complete and in service, was as safe as a tunnel constructed by any other means.[14]
In August 1997 the Health and Safety Executive decided to initiate legal proceedings and informed Balfour Beatty and Geoconsult. Balfour Beatty would plead guilty to violations of sections 2(1) and 3(1) of the Health and Safety at Work Act 1974. The Crown Prosecution Service declined to prosecute for similar issues in Terminal 4.
On 15 February 1999, Balfour Beatty and Geoconsult were found guilty of violating the Health and Safety at Work Act 1974. Balfour Beatty was fined £1.21 million (equivalent to £2.63 million in 2023), Geoconsult was fined £500,000 (equivalent to £1,094,434 in 2023). Both were also ordered to pay prosecution costs of £100,000 (equivalent to £218,887 in 2023).[15][16] Balfour Beatty's 1.2 million fine was the largest single fine for a Health and Safety Act violation at the time.[16]
In 30 July 1999, Geoconsult's application for leave to appeal against their earlier conviction was rejected, as was change in the financial penalties.[16] In 2000, Geoconsult GES told Uxbridge magistrates' court that they couldn't pay the 500,000 fine and 100,000 in additional costs after missing missing 15 February deadline.[17] As of May 2003, Geoconsult still hadn't paid the 500,000 fines.[18]
In July 2000, the Health and Safety Executive released the report into actual collapse, The collapse of NATM tunnels at Heathrow Airport. The release of this report was delayed until the completion of the various legal cases surrounding the collapse, to avoid interference with the outcomes.[19] In 2024, an individual filed a Freedom of Information request with the Health and Safety Executive for this report.[20] The requestor noted in the request that the 'part 1' report NATM tunnel method was available online through HSE, the 'part 2' report into the collapse itself was not available for some reason, prompting the request. This request revealed that in 2006, HSE's physical copy of the document was disposed of per HSE's Corporate Retention Policy, and that HSE was unable to locate any copies physical or electronic to fulfill the request.[21] After the requestor made further inquires, stressing the disposal seemed inconsistent with the policy and that the Part 1 report had been published years earlier, and was available through HSE, having had a digital reissue in 2014.[22] HSE then clarified that the hard copy was withdrawn 2006, and should have been digitized at the time, however HSE was unable to locate the digital copy in their internal archive or with The National Archives.[23]
See Also
[edit]- 2009 collapse of Historical Archive of the City of Cologne - Building collapse during construction of an underground portion of the Cologne Stadtbahn
Bibliography
[edit]- Health & Safety Executive (July 2000). The collapse of NATM tunnels at Heathrow Airport. Health & Safety Executive. ISBN 0-7176-1792-0.
- Vaughan, Adrian (2004). Railway Blunders. Surrey, UK: Ian Allan Publishing. ISBN 0 7110 2836 2.
- Health & Safety Executive (2014). Safety of New Austrian Tunnelling Method (NATM) Tunnels (PDF) (2nd ed.). Health & Safety Executive. ISBN 978 0 7176 1068 6. Retrieved 9 June 2025.
References
[edit]- ^ a b c d e Health and Safety Executive 2000, pp. 4.
- ^ Health and Safety Executive 2000, pp. 5.
- ^ a b c Health and Safety Executive 2000, pp. 48.
- ^ a b c Health and Safety Executive 2000, pp. 51.
- ^ Pilkington, Edward (24 October 1994). "Second slide strikes tunnel". The Guardian. The Guardian. Retrieved 31 August 2025.
- ^ a b c d Health and Safety Executive 2000, pp. 49.
- ^ a b Laville, Sandra (21 October 1994). "Heathrow chaos as landslip shuts roads and Tube". Retrieved 31 August 2025.
- ^ a b Morton, Ian; Tweedie, Neil. "250,000 hit as airport tunnel troubles go on". Evening Standard. London. p. 7. Retrieved 31 August 2025.
- ^ Murray, Dick (28 October 1994). "Heathrow Tube station shut for 3 more weeks". Evening Standard. p. 7. Retrieved 31 August 2025.
- ^ Coates, John (23 October 1994). "Heathrow tunnel fall 'triggered by Tube'". Sunday Telegraph. The Telegraph. p. 4. Retrieved 31 August 2025.
- ^ Health and Safety Executive 2000, pp. xx.
- ^ a b Health and Safety Executive 2000, pp. 54.
- ^ a b Health and Safety Executive 2014, pp. 5.
- ^ a b Health and Safety Executive 2014, pp. 15.
- ^ Vaughan 2004, pp. 142.
- ^ a b c Health and Safety Executive 2000, pp. 56.
- ^ Hall, Macer (27 February 2000). "Airport tunnel fall firm cannot pay fine". The Sunday Telegraph. Vol. 2020. London. p. 4. Retrieved 30 August 2025.
- ^ Evans-Pritchard, Ambrose (9 May 2003). "Britons will be tracked down to EU fines". The Daily Telegraph. No. 46004. The Telegraph. p. 2. Retrieved 30 August 2025.
- ^ Murray, Dick (5 July 2000). "Heathrow tunnelling chiefs 'put lives at risk'". Evening Standard. London. p. 22. Retrieved 30 August 2025.
- ^ "HSE Investigation into Heathrow Express Link". whatdotheyknow.com. 19 January 2024. Retrieved 30 August 2025.
- ^ Burslem, Amalia (5 February 2024). "HSE Investigation into Heathrow Express Link". Health and Safety Executive. Retrieved 30 August 2025.
- ^ "HSE Investigation into Heathrow Express Link". whatdotheyknow.com. 6 February 2024. Retrieved 30 August 2025.
- ^ Burslem, Amalia (8 February 2024). "HSE Investigation into Heathrow Express Link". whatdotheyknow.com. Retrieved 30 August 2025.
External links
[edit]
Works related to The collapse of NATM tunnels at Heathrow Airport at Wikisource
Media related to Category:The collapse of NATM tunnels at Heathrow Airport at Wikimedia Commons
