§ Mr. Norris
This is an operational matter for the Highways Agency. I have asked the chief executive to write to my hon. Friend.
Letter from Lawrie Haynes to Mr. Bob Dunn, dated 27 February 1995:I refer to your request in the House for information on the need for remedial works at Blackwall Tunnel. This is a trunk road operational matter and your request has therefore been referred to the Highways Agency.I imagine that your enquiry is a result of recent press reports about subsidence caused during the excavation of a pilot heading for the Jubilee Line Extension (JLE) at Blackwall Tunnel in Greenwich. These gave the impression that the problem was far worse than was the case. There has been no damage to the tunnels and no remedial works are required beyond placing grout and concrete in and around the pilot heading. The incident in question was in any case under the southbound tunnel exit ramp, not under the tunnels.You may be interested to know that the normal maintenance regime provides for routine work such as cleaning, removal of debris, changing of light bulbs etc. to be carried out in the northbound tunnel during regular Tuesday night closures. Such work in the southbound tunnel takes place under lane closures that are implemented on two nights every week. Further, there are full closures of the southbound tunnel on six Saturdays nights per year—three in March and three in November for more extensive cleaning works.As you know major refurbishment of the northbound Blackwall Tunnel was completed as recently as 1992 at a cost in excess of £20 million.A recent study of the southbound tunnel has shown that after being in operation for 27 years the cladding and the ventilation system are in need of refurbishment/replacement. These works will take about eighteen months to complete, and are planned to start in 1996/97. Suitable advance publicity will be arranged closer to the start of works.I hope this reply is helpful.