Reducing Wellington's inner-city speed limit to 30kmh would not prevent most injuries to pedestrians and cyclists, new analysis from the Automobile Association shows.
Only 60 of 141 injury crashes on roads being considered for a lowered limit involved speeds over 30kmh or at uncertain speed - and in 81 cases the speed was under 30kmh, police crash reports from 2008 to 2012 showed.
About half the injuries were suffered by pedestrians and cyclists, and the rest were drivers, passengers and motorcyclists.
Wellington City Council announced a $250,000 policy last month to reduce speeds to 30kmh on 64 inner-city streets, including parts of The Terrace and streets surrounding Cuba St, Courtenay Pl and Lambton Quay. The Golden Mile would remain at 30kmh.
The proposal is out for public consultation until March 9, and is due to be considered by councillors in May.
If speeds were lowered in the CBD, more people would cross streets unsafely and be injured, AA Wellington district council chairman Michael Gross said.
"Just as one doesn't cross a motorway, as humans we are more inclined to chance our arm to a greater degree when the speed limit is lower.
"Just lowering the speed limit won't necessarily change a great deal, [although] it might change the severity of the accidents."
Crashes at low speeds generally involved vehicles turning, reversing, parking, or simply one or both parties making a mistake, Mr Gross said.
Each year an average of three serious injuries and nine minor injuries were suffered from crashes over 30kmh, he said.
Council transport portfolio leader Andy Foster said the AA's data would not change his determination to reduce the CBD speed limit. A lower speed would eliminate those 60 injuries that happened above 30kmh.
"The crashes at the lower speeds would have happened anyway. Hopefully we'll pull down both the number and severity of [the higher-speed crashes]."
The AA was primarily concerned about travel times for motorists, but the mean speed in the CBD was about 30kmh anyway, so the policy would reduce injuries while not affecting journey times, Mr Foster said.
- The Dominion Post
Should Wellington have a new convention centre?Related story: $100m Hilton project back to drawing board