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United Kingdom, Glasgow - uk/23


West of Scotland Water Authority will invite tenders by the end of 1999 for 2 km-long, 2 m internal diameter sewer in the Kelvin valley. Sept 1999.


United Kingdom, Strathclyde - uk/22

Interceptor Sewer

  Contractor Byzak launched Herrenknecht TBM on 1.2 km-long, 4.4 m-diameter drive. Sept 1999.


United Kingdom, Channel Tunnel Rail Link - uk/21

Section 2 London

This section will run for 39 km from Southfleet Junction to Ebbsfleet and under the River Thames to West Thurrock and Dagenham from where it will be in tunnels 19 km long to London St Pancras. Design work commissioned by Union Railways North for tunnels under the Thames and east London and acquisition of land and underground rights are proceeding, all under a $440 million contract for preliminary works. Construction starts in mid-2001 with completion in 2007. June 1999.   Union Railways proposes to compensate landowners for subterranean rights of way by paying a guaranteed minimum of $850 each to avoid protracted negotiations. October 1999.   Invitation to qualify for list of contractors for 40 km of 7.8 m-diameter soft ground tunnels with 5 x 35 m-deep x 200-300 sq m ventilation structures. Five separate contracts: from King’s Cross station in central London to Stratford east of the city 2 x 7.5 km tubes requiring two TBMs and including two ventilation structures; construction of 1 km-long Stratford station 54 m-wide at 18 m depth; from Stratford to Barrington Road 2 x 4.7 km tubes requiring two TBMs and including two ventilation structures; from Barrington Road to Ripple Lane 2 x 5.3 km tubes using two TBMs and including a ventilation structure and a cut-and-cover section; and the twin-tube 2.5 km Thames tunnel between Swanscombe and Thurrock requiring a single TBM. Depositions should include details of the machines to be used. The first preferred contractors announcement in January, 1998 nominated Tracklink, a jv of Mowlem, Holzmann and Besix for Contract 210 London Tunnels West, and a jv of Nuttall, Wayss & Freytag and Kier for Contract 250 London Tunnels East. This programme was aborted by the government in favour of a two-stage approach that resulted in the North Downs tunnel and Kent stretch of the new line being built first. More information from www.ctrl.co.uk December 1999.   First contract awarded to AMEC Civil Engineering for preliminary works including three pipejack tunnels for electricity and gas main diversions, commencing January, 2000 value $1.6 million. Information from PXJESSEL@ctrl.co.uk January 2000.   The major construction companies have been invited to a London briefing on 29th February to outline the civil engineering contracts that will make up Section 2 of the CTRL between Southfleet in north Kent and St Pancras in central London. CTRL developer Union Railways and project manager and designer Rail Link Engineering will unveil the contract packages on which design work is well advanced and invitations to tender will be issued this summer. Work is scheduled to begin in mid-2001 for commissioning 2007. More from PXRAVENS@ctrl.co.uk March 2000.   Prequalification underway for supply of 26,700 rings comprising 9+1 segments with i.d. 7.15 m, thickness 35 cm, length 1.5 m and 700 rings comprising 7+1 segments with i.d. 6 m, thickness 30 cm. Contact through PXJESSEL@ctrl.co.uk March 2000. Rail Link Engineering announced that 12 organisations have been invited to tender for five contracts worth $900 million for 20 km of tunnels from St Pancras station, through east London, and under the Thames river into North Kent. Contract awards scheduled early 2001 with construction commencing mid-year. Contract 220 from St Pancras to Stratford: Balfour Beatty/Amec; Miller/Dumez GTM/B&M; Nishimatsu/Kvaerner; Necso/Galliford. Contract 230 Stratford Box: Carillion/Bachy Soletanche; Mowlem/Bouygues/Besix; Kvaerner; Necso/Galliford. Contract 240 from Stratford to Barrington Road: Balfour Beatty/Amec; Campenon Bernard SGE; Nishimatsu/Kvaerner; Costain/Skanska/Bachy Soletanche. Contract 250 Barrington Road to Ripple Lane: Nuttall/Wayss & Freytag/Kier; Miller/Dumez/B&M; Hochtief/Murphy; Costain/Skanska/Bachy Soletanche. Contract 320 Thames tunnels: Nuttall/Wayss & Freytag/Kier; Campenon Bernard SGE; Hochtief/Murphy; Mowlem/Bouygues/Besix. Information from PXRAVENS@ctrl.co.uk May 2000. Union Railways reports value of contracts as: contract 220, $280 million; contract 230, $135 million; contract 240, $170 million; contract 250, $143 million. Contact PXJESSEL@ctrl.co.uk May 2000.Tenders issued for CTRL contract 103 for civil works to build new tracks for CTRL and connections to West Coast and East Coast main lines to the north of Kings Cross and St Pancras stations, including realignment of the Midland main line and construction of new tunnels for Thameslink 2000 project. Four organisations will bid: Kier/Nuttall; Tracklink (Mowlem/Bouyges/Besix); Alfred McAlpine/Amec; and Hochtief/Norwest Holst. Contract award Spring, 2001 with work commencing six months later. Client is Union Railways (North) Ltd. Visit www.ctrl.co.uk August 2000. Prequalification underway for contract 105 for Union Railways at St Pancras to include deck extension of station and train shed, and refurbishment of station including Thameslink tunnels. For documents fax +44 (0)207 681 5546 or visit www.ctrl.co.uk November 2000. Contractor prequalification announced for design/construct contract 310, Thames to Dagenham as: Balfour Beatty; Eurolink (Miller/Dumez GTM/B&M); Hochtief/Norwest Holst; Necso/Galliford; Tracklink (Mowlem/Bouyges/Besix); and Alfred McAlpine/Amec. Preferred bidder will be announced late-2001 with site open Spring, 2002. Visit www.ctrl.co.uk and www.balfourbeatty.com 03/01. CTRL Shortlist AnnouncedUnion Railways (North) Ltd has announced the shortlisted tenderers for five contracts worth over $750 million to construct major elements of Section 2 of the Channel Tunnel Rail Link (CTRL). The contracts include 20 km of tunnels that will carry the CTRL from north Kent under the Thames and through east London into St Pancras Station.The shortlisted organisations for each contract are:Contract 220 - West London Portal (edge of Kings Cross Railway Lands) to Stratford Box: Balfour Beatty Group Ltd/Amec Capital Projects Ltd; Nishimatsu Construction Co Ltd/Skanska Construction UK Ltd.Contract 230 - Stratford Box: Tracklink (J Mowlem and Co PLC/Bouygues SA/Besix SA); Skanska Construction UK Ltd.Contract 240 - Stratford to Barrington Road, Little Ilford: Nishimatsu Construction Co Ltd/Skanska Construction UK Ltd; Costain Ltd/Skanska Construction UK Ltd/Bachy Soletanche Ltd.Contract 250 - Barrington Road, Little Ilford, to Ripple Lane, Dagenham: Edmund Nuttall Ltd/Wayss & Freytag AG/Kier Construction Ltd; Hochtief AG/J Murphy & Sons Ltd.Contract 320 - Thames Tunnels including northern and southern approaches from Swanscombe to Thurrock: Edmund Nuttall Ltd/Wayss & Freytag AG/Kier Construction Ltd; Hochtief AG/J Murphy & Sons Ltd.Preferred bidders for C230 and C320 are scheduled to be announced later this month (January) with the three remaining contracts awarded in February. All are scheduled to start on site in mid-2001. 03/01.Shortlist for contract 103 to be awarded Spring, 2001 are Kier/Edmund Nuttall and Hochtief/Norwest Holst. Work involves new tracks, connections and realignment together with new tunnels for Thameslink. Visit www.hochtief.de 04/01. Award of contract 230 for Stratford station box to Skanska/Nishimatsu/Cementation, value $150 million. Contract 320 including 2.5 km-long Thames twin-tube bored tunnels awarded to Hochtief/Murphy, value $185 million. Visit www.ctrl.co.uk 07/01. Latest contracts awarded:Contract 135 (St Pancras - Highways and Utilities) - approx. value £11.5 million, let to Edmund Nuttall Ltd; Contract 220 (Stratford to West London Portal) - approx. value £145 million, let to Nishimatsu/Cementation Skanska; Contract 240 (Stratford to Barrington Road) - approx. value £125 million, let to Costain/Skanska/Bachy Soletanche; Contract 250 (Ripple Lane to Barrington Road) - approx. value £115 million, let to Edmund Nuttall/Wayss & Freytag/Kier. More from www.ctrl.co.uk 09/01. Announcement of 8.1 m-diameter TBM orders as follows: contract 220 (Nishimatsu, Skanska) Stratford to Kings Cross, two Kawasaki dual mode EPBs; contract 240 (Costain, Bachy Soletanche) Barrington Road to Stratford, two Wirth EPBs; contract 250 (Nuttall, W&F, Kier) Ripple Lane to Barrington Road, two Lovat dual mode EPB/Open; contract 320 (Hochtief, Murphy) Thames Tunnels, two Herrenknecht Mixshields. Machine deliveries start May, 2002. Visit www.ctrl.co.uk 27/01. Tunnelling on Contract 240 of the Channel Tunnel Rail Link (CTRL) project was halted as engineers investigated the appearance of a huge crater across several gardens along the tunnel route. The collapse of old water wells built in the 1860s is believed to be the most likely cause of the landslip, which forced 50 people to evacuate their houses in Stratford, east London on 8th February. All but two of the households were allowed back on 10th February. The 10 m-deep crater happened more than a day after a 120 m-long TBM - nicknamed Hudson - boring a 8 m-wide tunnel passed below the houses on Lavender Street. The tunnel remained intact. A joint venture involving Costain, Skanska and Bachy Soletanche was awarded a £125 million contract for the section between Stratford and Barrington Road and started work last November. The tunnel is the first of two being bored at 85 metres per week by the 1,100-tonne machine carving through chalk, sand and London clay. A second TBM, named Brunel, is working in conjunction with Hudson. The tunnelling work, 20 m below the surface, is pending the outcome of an inquiry. Hundreds of tonnes of concrete were poured into the 10 m-wide hole. Officials said they knew of the wells but residents accused London and Continental Railways (LCR) of ignoring their warnings. The £5.2 billion CTRL is being constructed in two sections. Work on the 74 km stretch from the Channel tunnel entrance to Fawkham Junction in North Kent began in October 1998. It is now 92% complete and should open next year. The second phase - 39 km between Southfleet, North Kent, and the terminal at St Pancras - got under way in July 2001 and is more than a third finished. Visit www.ctrl.co.uk. 08/03. The Health and Safety Executive (HSE) has given the go-ahead for tunnelling to restart on the Channel Tunnel Rail Link west to east tunnel between Stratford and Barrington Road (contract C240). Digging work resumed on 30th April after a ground collapse damaged homes and swallowed gardens in Lavender Street, Stratford (east London) last 8th February. The decision has triggered protests from residents who say they have yet to receive any credible explanation as to why the first collapse happened, or guarantees that there will not be a recurrence.In a letter, the HSE says that "further anomalies in the ground ahead of the down line and up line tunnels cannot be ruled out" and adds "We recognise that there is no technique available for reliably determining the location of each and every significant anomaly that may be in this area". The HSE has told the contractors to improve testing and monitoring procedures and to be ready with "emergency procedures in the event of any sudden collapse of ground".The area being tunnelled is dotted with underground wells and streams. There are also believed to be a number of unexploded bombs from the second world war. Work on the 4.5 km stretch of tunnel in Stratford may be especially risky because the plan is now for one EPB tunnelling machine to overtake the other. Previously they were set so that one was always 50 metres behind to avoid too much ground disruption at the same point. One Wirth TBM is still underneath Lavender Street, where the ground collapse occurred. The other machine, which is the first to be reactivated, is 150 metres away, beneath the car park of a warehouse. The machine involved in February's ground collapse is expected to be reactivated in mid-May. 19/03.Second breakthrough completed 2.5 km-long Thames tunnel 50 days ahead of schedule. Hochtief-Murphy jv 8.15 m-diameter Herrenknecht TBM negotiated water-bearing alluvium, terrace gravels and chalk at rates up to 170 m/week at up to 40 m below surface of river. Total 560,000 cu m excavated in two tunnels. Visit www.herrenknecht.com 42/03.Nishimatsu-Cementation Skanska jv has passed the 5 km mark on the 7.5 km-long Stratford tunnels of Contract 220, from which 1.6 million t will be excavated to breakthrough in early-2004. Visit www.ctrl.co.uk 42/03.


United Kingdom, Channel Tunnel Rail Link - uk/20

Section 1 North Downs

Rail Link Engineering designing and managing construction for Union Railways South for section from Folkestone to Fawkham junction. Contract 410 is for tunnel 3.2 km-long with 160 m2 excavated section using sprayed concrete awarded to Eurolink jv. Completion 2003. May 1999.   Contract to supply steel lattice arches awarded to ROM Tunnelling. October 1999. Kvaerner Construction reports that it is working on a $225 million section of CTRL at Ashford, Kent which includes 17 km of civil engineering with cut-and-cover tunnels through the town centre, a three-span bridge and links into the existing international station without interruption to the railway timetable. Details from www.kvaerner.com April 2000.North Downs tunnel breakthrough reported by Rail Link Engineering (RLE) two months ahead of schedule and $7.5 million under budget. The 13 m-wide x 3.2 km-long structure installed at maximum depth of 90 m is the largest mainline train tunnel in the UK. 500,000 t was excavated in chalk as a 66 sq m crown heading followed by bench and invert, using 4 m rockbolts, mesh, lattice girders and 40,000 cu m sprayed concrete. Best progress was: crown 81 m/week or 14 m/day; bench 181 m/week; and invert excavation and blinding 1,322 m/week. RLE comprises Bechtel, Ove Arup, Halcrow, and Systra and is responsible for the design and project management of the rail link. Visit www.ctrl.co.uk June 2000.74 km-long Section 1 of CTRL officially opened by prime minister on 16th September, 2003 and commenced operation on 28th September, 2003, on time and within budget. Journey time London-Paris now around 2.5 h. Eurostar train set new British speed record of 334.7 km/h on safety test 30th July, 2003. Visit www.ctrl.co.uk 42/03.


United Kingdom, Woolwich - uk/19

Light Rail

  Crossing under Thames to connect with City Airport promoted by London First. March 1999.   Docklands Light Railway estimates that its passenger volume in Docklands, east and south-east London will reach 60 million/year by 2004, by which time extensions to City Airport and North Woolwich will be in operation. Further extension of the railway to Woolwich Arsenal by 2006 will require a tunnel under the Thames. Visit www.londonunderground.co.uk August 2000.  Feasibility study for 2.5 km-long tunnelled cross-Thames extension from Beckton to Woolwich completed by W S Atkins. Construction start mid-2004 for completion in three years. Mowlem and Amec bidding for concession. Visit www.dlr.co.uk 44/01.Negotiated procedure, deadline 23rd January, 2004 for design, build, finance and maintenance contract of an extension of the Docklands Light Railway between King George V and Woolwich Arsenal including twin bored tunnels under the Thames. Visit http://ted.publications.eu.int/udl?request=Seek-Deliver&language=en&docid=211530-2003, OJ S 237, or contact Docklands Light Railway Ltd, London, fax +44 2073639708. E-mail dkeep@dlr.co.uk 51/03.The Woolwich Arsenal Rail Enterprises (WARE), a 50/50 joint venture between Amec and the Royal Bank of Scotland, has been appointed preferred bidder for the GBP200 million extension of the Docklands Light Railway (DLR) to Woolwich Arsenal. Under the terms of the contract, WARE will manage the design, build, finance and maintenance of the 2.5 km extension from King George V station under the Thames to Woolwich Arsenal station. This includes overseeing the twin bored tunnel excavation under the Thames and the construction of a new station integrated with the existing Woolwich Arsenal Network Rail station. Each of the twin tunnels will have a diameter of 5.2 m and a length of around 1.8 km. The remainder of the extension runs in cut and cover. The JV is expected to reach financial close on the PPP scheme in time for construction to begin in spring 2005. Completion is due in winter 2008/09. Visit www.amec.com and www.tfl.gov.uk/dlr/index.shtml 53/04-01/05.AMEC has contracted with Lovat for the purchase of a new TBM for the Docklands Light Rail (DLR) extension from King George V station to Woolwich Arsenal in east London. Lovat is to design and custom manufacture a 6 m-diameter soft ground machine. Crossing the Thames, the TBM model ME238SE series 21800 is to bore a 1.83 km twin tunnel. The machine will be erecting and installing prefabricated concrete segments, forming an 8-piece, tapered trapezoidal ring, having an outside diameter of 5.8 m and an internal diameter of 5.3 m. The machine features a screw conveyor with a peripheral drive mechanism for a rear discharge to a muck pump. This approach will be taken for material removal for the first 300-500 metres, then switched to a continuous belt conveyor for the remainder of the drive. The geology expected along the tunnel alignment will generally consist of terrace gravels, chalk and Thanet sands. This EPB machine is expected to encounter pressures of 4 bar. Delivery to the site is expected by November 2005. Visit www.lovat.com, www.amec.com and http://developments.dlr.co.uk/extensions/woolwich/index.shtml 25/05.


United Kingdom, London - uk/18


  Proposal for self-financed tolled second crossing of Thames put forward by London First, a business organisation. March 1999.Restricted procedure, deadline 19th April, 2004 to undertake preliminary design and feasibility studies, prepare a detailed design specification and contract documents and then, in the construction phase, act as the client's representative for the refurbishment contract or contracts on the existing 1.2 km Blackwall tunnel northbound. Works will include refurbishing and upgrading the tunnel services, including ventilation, control of mechanical services, tunnel lighting and communications systems, and works to the tunnel structure, including the walkway, lining and road surfacing. Visit http://ted.publications.eu.int/udl?request=Seek-Deliver&language=en&docid=045743-2004, OJ S 53, or contact Transport for London, London, fax +44 2070279861. E-mail meeramajithia@streetmanagement.org.uk or johnnewham@streetmanagement.org.uk 14/04.Restricted procedure, deadline 3rd March, 2006 for refurbishment work of the A102 Blackwall tunnel northbound tube (1,360 m) in London, including mainly as follows: removal of cladding and replacement with a fireproof lining; lighting; communication; traffic control signals; drainage; fire and incident detection; fire main and hydrants; escape route signing; and PTZ and fixed cameras amongst others. The contract value is estimated at GBP40 million. Visit http://ted.publications.eu.int/udl?request=Seek-Deliver&language=en&docid=019592-2006, OJ S 18, or contact Transport for London, London, fax +44 2076543773. E-mail lilianwong@streetmanagement.org.uk. Read E-News Weekly 4/2006. 06/06.Restricted call for tenders, deadline 7th September, 2007 for the 1.4 km Blackwall northbound tunnel refurbishment on motorway A102. This is a re-bid. Read E-News Weekly 33/2007. Visit http://ted.europa.eu/udl?request=Seek-Deliver&language=en&docid=178762-2007, OJ S 144, or contact Transport for London, London, fax +44 2071261002. E-mail lilian.wong@tfl.gov.uk 34/07.Restricted call for tenders, deadline 30th September, 2008 for the 1.4 km Blackwall northbound tunnel refurbishment on motorway A102. This is a second re-bid. Visit http://ted.europa.eu/udl?request=Seek-Deliver&language=en&docid=191658-2008, OJ S 143, or contact Transport for London, London, fax +44 2030542006. E-mail christopher.carroll@tlf.gov.uk 31/08.


Contract, value approx EUR56.3 million, for A102 Blackwall tunnel northbound refurbishment awarded under negotiated procedure to BAM Nuttall Ltd of Maidstone ME17 1AH, Kent, UK. More from Bill Egan at Transport for London, tel +44 8453051234, fax +44 2030542006. Visit http://ted.europa.eu/udl?request=Seek-Deliver&language=en&docid=037779-2010. 06/10.


Flakt Woods, in conjunction with the M&E sub contractor VVB Engineering Services Ltd, has been awarded a EUR600,000 contract to supply the fans for the ventilation system for the contract to upgrade the 113 year old northbound bore of the 1364 m Blackwall tunnel in London. The Blackwall Tunnel runs underneath the River Thames, linking Tower Hamlets with Greenwich, and part of the A102 road. Work includes installing new ventilation fans in the tunnel's four shafts as well as new lighting, upgraded CCTV and new communications systems installed throughout the tunnel. The client, Transport for London(TfL) has also begun installing 26 safe areas or niches inside the tunnel, including emergency phones and fire extinguishers.Flakt Woods is providing 16 of their 160JMFTS vertically mounted smoke vent category: 400 degrees C for 2 hour type fans, as well as JM type axial fans.For more click here, here and uk/18. Visit www.flaktwoods.com/it and http://vvb-eng.com/business-sectors/roads-highways/blackwall-tunnel-northbound-refurbishment/. 31/11


United Kingdom, Ramsgate - uk/17

Road Tunnel Harbour Access

Contract awarded to Taylor Woodrow Construction/Perforex jv for 800 m tunnel through chalk cliffs using prevault system in which a slot is milled over the crown and pumped full of shotcrete prior to sequential excavation of the face. Partnership team combines the jv partners with Kent County Council, Brown & Root Civil, Halcrow, Taylor Woodrow Foundation Engineering and earthmover C A Blackwell. Safety Passport scheme in operation for underground workers. April 1998.  Successful breakthrough reported September, 1999. Claimed as a milestone in use of prevault method. October 1999.


United Kingdom, Workington - uk/16

Interceptor Sewer

North West Water $30 million design and construct contract awarded to AMEC Tunnelling for 2.02 km, 2.85 m diameter sewer in glacial alluvium containing clay and sandy deposits at maximum depth of 17 m using Lovat EPB and 350 m, 1.5 m diameter using Iseki Unclemole, and four shafts from 6 m to 9 m diameter and two branch connections. Bechtel Water Technology is consultant. February 1999.


United Kingdom, Portsmouth - uk/15

Sewage Transfer

Two drives totalling 8 km using two Lovat RME 131SE earth pressure balance machines with mixed face cutting heads capable of operating in open or EPB mode. First drive 4.2 km through predominantly chalky formations with flint content of 5% to 60%; dense calcareous sands, gravels and shelly beds; and very stiff clay with silty, sandy composition. Second drive 3.8 km through chalks with flint content of 5% to 14.4%. Both drives beneath water table at average depth of 21m. Nov 1998.  $40 million transfer tunnel nearly complete, with overall contract completion scheduled for January, 2001. At the mid point of the 8 km-long, 2.85 m i.d. tunnel two 7 m-diameter drive shafts lined with pre-cast concrete segments were sunk in chalk using the dry caisson technique and local dewatering. Reception shafts 25 m-deep x 6 m-diameter were sunk at Budds Farm by dry caisson in chalk with flints, and 35 m-deep x 6 m-diameter at Eastney by wet caisson in sands, silts and clays, and a 10 m-diameter pumping shaft has also been built at Eastney. Lovat 3.36 m RME131SE series 18900 EPB has completed and has been upsized and transferred to Cork ie/15, while sister machine series 18800 EPB has 200 m to go to breakthrough. Six-piece bolted, trapezoidal, segmental, steel fibre reinforced tunnel lining rings, nominally 1 m-long, supplied by Macrete of Northern Ireland. Visit engineering consultants www.halliburton.com, contractor www.edmund-nuttall.co.uk, segment supplier www.macrete.com and TBM supplier www.lovat.com August 2000.


United Kingdom, Hull - uk/14

Connector Sewer

  $82 million contract awarded by Yorkshire Water to Miller Civil Engineering and Birse Construction joint venture for 10.5 km tunnel, 3.6 m diameter and some 22 m deep with 10 shafts to connect sewers in west and east Hull passing beneath the river, the marina and the docks. Two new Lovat 4.24 m mixed-face TBMs will bore through alluvial sands, glacial clays and tills, silts, sands and gravels with groundwater pressures of 1.9 to 2.3 bar. Maximum cover 16 m and minimum radius 300 m. Three sections to be bored: 5.5 km, 3.33 km and 1.78 km. Machines powered at 672 kW and can run in open or closed mode. Six-piece 3.6 m i.d. segmental trapezoidal lining in rings of 1 m width. March 1998.   Ten 25 m-deep shafts constructed as jacked wet caissons using Charcon segments. Two identical Lovat mixed face EPBs delivered October, 1998. Bore diameter 4.24 m, maximum thrust 2,400 t with 672 kW cutterhead power through ten variable displacement hydraulic motors. Six-piece Charcon trapezoidal segmental lining in 1.0 m rings of 4.1 m outside diameter and 3.6 m internal diameter. Schoma locomotives and UMD rolling stock. Sept 1999.   Collapse of 15 m-long section of segmental lining occurred 150 m behind one of the TBMs in mid-November without injury or loss of life. January 2000.  Yorkshire Water has decided to recall its Lovat EPB Gloria to complete the final section of its stricken 10.6 km Humber wastewater tunnel at Hull in the north of England. Some 80% of the tunnelling had been successfully completed when a section of the 3.6 m i.d. segmentally-lined tunnel mysteriously collapsed some distance behind the face. Investigations are continuing into the cause of the incident, and there is presently no indication of anything other than a localised situation. The affected area has been stabilised using compressed air, and will be dug out and relined conventionally. A 22 m-deep retrieval shaft will be sunk 50 m ahead of the idle face, and TBM Gloria will drive towards it in an easterly direction from an existing launch shaft. Because the tunnelling was running three months ahead of schedule at the time of the incident, the original project deadline of November, 2000 is not affected. More at www.yorkshirewater.co.uk March 2000.Extensive ground investigation since the collapse has identified a layer of heavy peat at 40 m depth, some 18 m below the tunnel alignment, which may have caused the ground movement that resulted in failure of the non-bolted segmental concrete lining, trapping the TBM. The final 2km of the drive has since been completed by Miller Tunnelling using its second Lovat TBM. Work is proceeding to recover the trapped TBM. Visit www.millerconstruction.co.uk August 2000.