Many of the Mayoral candidates have been advocating it and are backing the decision because they know that its popular with the public. In the 2010 British Social Attitudes Survey 71% of people asked were in favour of 20mph speed limits on residential roads - http://tinyurl.com/cx2r2ca.
Some persist in saying that here is no logical or proven reason for 20mph limits in residential areas but in fact there's plenty of research around. See this analysis of the effectiveness of 20mph speed limits from the Royal Society for the Prevention of Accidents (http://tinyurl.com/bqbdogs) for instance. Those opposing 20 mph limits seem to be driven by something other than the evidence and reasoning upon it - see the debate on this story on The Post website here - with even more here - for plenty of examples of abuse, avoidance, denial, misinformation and misunderstanding...
Some repeat myths in their comments eg saying that air pollution would be worsened. Actually 20mph limits will NOT increase air pollution, as shown here http://tinyurl.com/7gp2j89 and are a key feature of a more sustainable approach to urban living. The key is that the streets involved in this decision are residential streets ie people live there. Living there need not and most often does not exclude driving there of course but lets not forget that cyclists and pedestrians and not just motorised vehicles use roads and that all sorts of community activities can and should happen on residential streets if they are safe enough - and this brings me to another reason why I say streets are for living (by which I meant primarily for living) and that is that if the speed limit is 20 mph, in the unfortuneate event of a collision the people involved are much more likely to live than to die.
Some still argue that roads/streets, even residential ones, are primarily for cars and not pedestrians, cyclists and a range of activities, potentially. However, many of the roads/streets in Bristol were there long before cars were owned and used on a widespread basis and some go back even before the invention of the car. Mass car ownership did not take off in the UK until the 1950's and many things have happened on the roads/streets before and since. A good proportion of Bristol's roads/streets were never designed for cars. Roads are simply thoroughfares, routes, or ways on land from place to place - and in residential areas and in cities serve a wider purpose, including easement. Even where they were/are specially designed for car use why should we not choose, with general agreement, to adjust and manage that, especially in residential areas, so that the balance favours human beings not motorised machines running at a speed likely to kill or cause serious injury? See http://tinyurl.com/2vd7pq and also http://tinyurl.com/cgphzz7.
Others say introducing 20mph limits is a waste of money, can't be enforced and everyone will ignore it. They seem to have forgotten the evidence eg from RoSPA on their effectiveness. 20mph limits have saved lives where they have been introduced in Hull, London and elsewhere. See here. No-one has been able to dispute this evidence in the two lengthy online debates I've taken part in.
