Sir, - Once more Kevin Myers hits the nail on the head - I refer to his excellent piece (An Irishman's Diary, August 24th) on our local authorities' obsession with the roundabout as the traffic interchange of choice. The larger the roundabout the better and, when its failure adequately to function must be acknowledged, acknowledgment takes the form of traffic lights on the roundabout, carefully unsynchronised.
Ireland is alone in Europe in using a be-traffic-lighted roundabout to connect two motorways, the M1 and M50. It, and the other monstrosity at Firhouse, actually cannot be negotiated properly according to standard roundabout driving rules: it is always necessary to side-slip across lanes on the roundabouts between entry and exit. Mr Myers correctly points out the insanity of unnecessarily mixing four streams of traffic from different directions in a one-dimensional cauldron. He does not explicitly use the term for what our roundabout-and-traffic-light intersections should be: grade- separated interchanges.
Sixty years of experience building motorways has led to the international acceptance of such interchanges as the best method of intersection. They are everywhere in continental Europe (our friends across the water have them too, but succumbed early to a mild form of the roundabout disease, which is probably the source from which we contracted the full-blown variant). In Denmark, indeed, roundabouts are officially being phased out, judged, as they are, to be a road hazard.
As its name suggests, the grade-separated interchange is multilevel: left-turn is a slip-road; straight ahead is unobstructed straight through; the right turn is an over-the-top flyover merging from the left with the right-angled motorway perhaps half-a-mile to the right. No hold-ups, intentional obstructions or malevolently-placed hazards. We in Ireland, blessed with unique insight that improves upon all precedent, of course know better. Cinnte! The M50.
The reason why we have roundabouts instead of proper interchanges is that roundabouts are cheaper, at least to build. We will, however, be paying for them for decades of deaths, accidents, traffic hazards, mile-long tailbacks, fuel wastage, lost time and justifiable rage on the part of taxpaying motorists.
Will any public official answer this? Can we at least stop imposing more roundabout insanity on the tax-paying motorist? - Yours, etc.,
Conor Sexton, Castleside Drive, Rathfarnham, Dublin 14.