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More efficient junctions

My mum always used to say that when lights were introduced to any junction, things always got slower and more messed up than before. According to this article from Salon, she was right. They propose a solution to avoid needing the lights – you slow down the traffic to 20 mph, and then the junctions operate more efficiently.

It fits into an overall approach of depending on drivers and other road-users to ‘do the right thing’ on the road rather enforcing a strict set of rules, with lots of signage and lines on the street.

The interesting thing about this for Ireland is that there is going to be a change in speed limits in urban areas in Dublin over the next year or so. We are going to change from imperial to metric speed limits.

At the moment, the speed limit in urban areas is 30 mph. If the government was to leave the existing signage in place and change it to kilometres, that would bring the limit down to 18.5 km/h. If the theory described in the Salon article works, it would allow a lot of traffic lights to be taken out on certain streets (for example, in places like Donnybrook, Ranelagh and Phibsborough). This could make well make things run more smoothly.

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  1. What about left turn on red? The greatest single benefit offered by California to the culture of the world is “right turn on red” (RTOR). I think the mirror image of it (LTOR) in Ireland would cut my weekly petrol bill by nearly 5% each week.

    What about taking all the traffic signals you’re going to remove with Antoin’s proposal and installing them in the middle of streets where they stay green all the time . . . until a speed detector senses someone traveling more than 10 mph over the limit, then the lights change to red.

  2. The reason Ireland’s speed limits remained, curiously, in mph when its distance measurements changed from miles to km is that Ireland’s car market is but a small carbuncle on the side of Britain’s, and so we all drive British spec cars. Changing to kph requires speedos in every car to change.

    Maybe the British car industry has finally decided to introduce an Irish spec with a kph speedo instead of mph, but I doubt it.

    Thus only cars imported from Japan and OZ/NZ will have the steering wheel on the correct side and the speedo correctly calibrated.

    An Irish non-solution to an Irish problem !

    A more interesting question is why Ireland changed to kilometres in the first place. Surely it could not have been merely to cock a snook at the giant neighbour ? Could it ?

    T o n y

  3. Cars are not mass produced any more. The vast majority are built to order. When you go into a dealer and say you want a particular model in Silver grey, with the CD changer option and the sunroof, the order is sent to the factory and that car is built and delivered. Specifying a kmph or mph speedo is no different to specifying a different optional accessory.

  4. The deal (as I understand it) with the road signs in kilometres has more to do with EU funding than the post-colonialist mindset. The signs were extremely unpopular with motorists when first introduced.

  5. the four way stop would be a disaster it creates uncertainty as to who move first if there is a vehicle on each road ,it has been tried in australia and was given up as a bad joke after many deaths