The announcement that Norwich City Council intends to extend 20mph speed limits throughout the city is not surprising, despite being of little or no obvious benefit to the community.

Speed limits of 20mph were originally introduced as a means of reducing accidents and casualties but experience has shown that it is virtually impossible to detect any such reduction.

In reality the justification for these limits has changed from improvements in road safety to rather more nebulous and indefinable benefits.

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Quoting Bert Bremner of Norwich highways committee: 'We have a positive approach to 20mph. The benefits have been spilling out. The changes in areas are just really positive. In all areas where zones have been introduced to date, we've seen a reduction in vehicle speeds.'

Not one single mention of what these alleged benefits might be, no statistics on any reduction in accidents or injuries, no statistics on improvements in pollution from vehicles and no information on any changes in traffic flows.

The only noteworthy change that has been recorded is a reduction in traffic speeds.

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If other bodies are having second thoughts on extending 20mph speed limits, based on sound statistical evidence, it would surely be prudent for the city council to evaluate the experience they already have, over areas with 20mph limits and with 30mph limits, before they commit the taxpayer to expenditure that may well be totally wasted.

Otherwise the current policy simply degenerates into a pet vanity project by councillors with little or no benefit to the community.

L J Paterson, Ollands Road, Reepham