HC Deb 16 June 1965 vol 714 cc439-41
17. Sir B. Janner

asked the Minister of Transport if he will make a statement on the tests which have been made on the M.2 with the use of rosa multiflora japonica bushes as anti-dazzle barriers and their advantages as road safety devices; and if he will arrange for future lengths of motorways to be sufficiently wide for the placing of these shrubs in the centre.

Mr. Swingler

The tests, which are being carried out with indigenous shrubs not with rosa multiflora japonica, are designed to ascertain whether plants can survive in the difficult conditions prevailing on the central reserve of motorways in this country. The experiment has been in progress for only a few months and it is too early to draw any conclusions. Experiments at the Road Research Laboratory have shown that the central reserve would have to be several times wider than the present standard 13 ft. to accommodate a hedge of rosa multiflora japonica thick enough to act as an effective crash barrier. We do not consider that the cost of this would be justified.

Sir B. Janner

Will the hon. Gentleman give this matter further consideration, in view of the fact that this device has been extremely useful in preventing accidents in other countries? Will he see to it that in future, when a length of motorway is constructed, it will he sufficiently wide to allow for the planting of this kind of bush? Is he aware that if this had been done previously many accidents would not have occurred?

Mr. Swingler

We are certainly determined to carry on with the experiments, at any rate with the 11 indigenous shrubs, like hawthorn, privet and broom, whether or not we use rosa multiflora japonica. But I must tell the House that we are advised, as a result of the experiments of the Road Research Laboratory, that we should need a central reserve of 52 ft. compared with the 13 ft. we have now in order to provide for a fully effective crash barrier, and that this would add £110,000 per mile to the cost. That is the result of the work of research scientists. That is the advice that we have at the moment, but the experiments will continue in an effort to find the best results.

Sir J. Langford-Holt

Is it not fantastic that five years after motorways first came into existence we still have not made up our minds what can be done to prevent dazzle from oncoming traffic?

Mr. Swingler

It is not a question of making up our minds. We are continuing to investigate the possibilities of improving the methods of counteracting dazzle, and at the same time trying to provide an effective crash barrier in circumstances where vehicles are travelling at very high speeds. What I have said is based upon the experiments carried out by the people who are best qualified at the Road Research Laboratory. That is the scientific advice that we have at the moment.