Motorway Surfaces: Weather Effects (Hansard, 24 June 1993)

The Minister of State, Department of Transport (The Earl of Caithness)
My Lords, standards and specifications used for the design and construction of motorways make due allowance for the effects of hot weather. The recent problems were exceptional. Any such problems are rectified as quickly as possible and in such a way as to cause minimum inconvenience to road users. Any significant failures are investigated and specifications changed if necessary.

Lord Campbell of Croy
My Lords, I am grateful to my noble friend for his reply. Has the cause of the closure of the stretch of the M.4. on 9th June yet been diagnosed? Is it correct that that was the fourth failure in hot weather over the past four years on a stretch of road where disruption arises for passengers trying to reach Heathrow Airport?

The Earl of Caithness
My Lords, we are looking into the cause of the buckling of the concrete by the Heston service station on 7th and 8th June. That is being investigated by the department and the TRRL. There have been other cases of buckling in hot weather. However, if my noble friend considers that the M.4. is now 28 years old, that it carries about 100,000 vehicles each day and that it has not undergone major structural repairs, I am sure he will agree that that is a very fine performance.

§ Lord Clinton-Davis
My Lords, does the Minister agree with the view of the British Road Federation that 5,000 miles of road are in urgent need of repair this year and that a further 3,700 miles will wear out over the next four years? Was not his reply to the noble Lord, Lord Campbell of Croy, therefore somewhat complacent? Is he really satisfied with the present situation? What was so exceptional about the circumstances which gave rise to those problems over a period of four years?

The Earl of Caithness
My Lords, a great majority of the questions posed by the noble Lord relate to roads in general rather than to the Question on the Order Paper. The likely cause of the buckling of the concrete on the M.11 and M.4. on that exceptional day is compression failure. The noble Lord will be interested to know that there was one such incident on the M.4. and four such incidents on the M.11.

§ Lord Clinton-Davis
My Lords, what is being done to deal with those failures and to ensure that there is no repetition?

The Earl of Caithness
My Lords, as I said in my original Answer, an investigation is under way into both those incidents, as it is into other such serious incidents. If there are lessons to be learned and specifications to be changed, that will be done.

§ Lord Boyd-Carpenter
My Lords, as the Minister responsible for the decision to build the M.4., I thank my noble friend for his generous tribute.

The Earl of Caithness
My Lords, I am sure that I am not the only person in your Lordships' House to pay tribute to my noble friend for the M.4. It is of great convenience to me when I need to go home.

§ Lord Monkswell
My Lords, given the Minister's suggestion that there have been previous road failures due to hot weather, has any provision been made of sprinklers or sprinkling equipment to cool down the roads?

The Earl of Caithness
My Lords, not to my knowledge. The incidents are few and far between, as they are in other countries where similar failures have occurred. There are over 2 million concrete joints in roads in this country. It would be quite an expensive operation to provide sprinkler systems for each of those joints.

Lord Campbell of Croy
My Lords, is the road surface of motorways affected in hot weather by excessive speeds or the weight of large vehicles?

The Earl of Caithness
My Lords, generally, no. The specification the department uses, which has been improved over time as we have learnt lessons from the past, is such that it is designed to cope with hot weather, and heavy and continuous use by traffic. There might be a problem if a tarmac road has been resurfaced with tarmac, because the bitumen takes longer to dry and set in hot weather than in cold weather.

§ Earl Russell
My Lords, does the Minister remember that the last time the Conservative Party had been in power this long it opened a motorway in Preston which broke up immediately? The Minister came to the Dispatch Box and said that he was very sorry but that it had been caused by frost. May I deduce that the only thing that has changed in 30 years is global warming?

The Earl of Caithness
My Lords, one of the advantages of being in this Government is that one has opportunities to open motorways, something that the party of the noble Earl will be unable to do.