Reducing the speed limit to 30kmh in Wellington's central business district is expected to save the city nearly half a million dollars a year.
City council calculations suggest the proposal to knock 20kmh off the existing limit will significantly reduce crashes and the $10.5 million bill they generate annually, but add less than a minute on to most car journeys across the central city.
The council's transport and urban development committee will this week be asked to support a reduction of the speed limit from 50kmh to 30kmh across central Wellington from the railway station to Vivian St.
In a report to the committee, the council's safe and sustainable transport manager Paul Barker said 30kmh inner-city limits introduced elsewhere, both here and overseas, had coincided with a reduction in crashes of between 10 and 50 per cent.
But even a "conservative" reduction of 8 per cent in Wellington would knock $477,000 off the social cost to the city each year, he said.
"A legal speed limit of 30kmh will deter the significant minority who drive too fast for the conditions."
Between 2009 and 2013 there were 648 crashes in Wellington's CBD, with 99 involving pedestrians.
Committee chairman Andy Foster said the $250,000 cost of expanding the 30kmh zone, which the council would split with the NZ Transport Agency, had copped some criticism. But Barker's report had shown it would pay for itself inside of a year.
"If crashes are costing the community $10.5m a year then spending $250,000 to knock some of that off is not a lot."
Barker said in Bristol in the United Kingdom a reduction from 50kmh to 30kmh in the CBD added less than a minute to 8 kilometre vehicle trips across the city.
Having a "part-time" 30kmh limit in central Wellington was not an option because it would confuse drivers and cost too much, he said.
Barker's report showed that, although average speeds through much of the CBD were about 30kmh at present, some cars were hitting speeds of between 70kmh and 80kmh in free-flowing conditions, particularly on parts of Tory St.
Wellington mayor Celia Wade-Brown said tourists, school groups and people on staggered lunch breaks were all out and about in the CBD between peak periods, and motorists needed to be mindful of sharing the space.
"This isn't about getting cars out of those streets. We're just saying that people need to be there by whatever mode of transport, so just calm it down."
- The Dominion Post
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