Advance Warning of Speed Limits

Thanks to Group member Doug Barr for his piece commending ‘slow-down zones’ with progressively reducing speed limits before a town or village 30 mph limit. Doug also floated the idea of different speed limits on each side of the road in areas like this.

For example, coming into Macclesfield from the north on the Silk Road, there is a 30 mph limit to protect the pedestrian crossing just before the Hibel Road roundabout. This is very sensible, even though the limit is commonly more honoured in the breach than in the observance. Leaving the roundabout northwards, however, especially as the road is a dual carriageway, maintaining the 30 mph limit for the southbound protection distance before you reach the national limit signs often causes visible frustration among, and unpleasant tailgating from, following drivers. In the early days of the IAM, this would have been classed as ‘driving without due consideration for other road users.’ An immediate release to the national limit after the pedestrian crossing would make complete sense.

Doug reported that some people whom he had discussed slow-down zones with had expressed the view that an aware driver should never be caught out by a change from the national speed limit to 30, but others had agreed that slow-down zones were a good idea.

On the A55 westbound (approaching Colwyn Bay?) there used to be, and perhaps still is, a 50 mph speed limit introduced on a curve, down from the national limit of 70 mph, without prior warning. One could be driving at 70 safely and realistically with regard to the traffic conditions, and able to stop within the distance that one could see to be clear, but still be embarrassed to slow down sufficiently and in good time for the 50 limit because of the risk of following traffic being caught napping. This is another situation where distance-to-go signs, like those used before the 30 limit for some villages, but earlier to suit motorway speeds, would be valuable.

For a further thought, here is an item that we first published in our May 2007 Newsletter:


Some towns and villages in Portugal have a sign saying (in Portuguese) ‘Controlled speed’. A hundred metres or so along the road is a set of traffic lights. If a vehicle enters the speed-limited area above the 50 kph speed limit, the lights go red for a short while.

How simple, and how effective. Whether a driver is over the speed limit deliberately or inadvertently, he is brought in check. If he was ‘pressing on’, he will lose more time stopped at the red than he would have done complying with the speed limit in the first place. And the system has the very beneficial side- effect of encouraging a community interest in observing the limits, because if one driver triggers a red, everyone who was observing the limit has to slow down or stop as well.

It would be good to see the IAM Motoring Trust promoting this system in this country. It would not bring in the revenue stream that ‘gotcha’ cameras 50 yards or so inside speed limit signs probably do, but as a positive measure inviting the intelligent and public-spirited cooperation of all the driving and riding community, it would be excellent.