There has been disappointment Waka Kotahi is slipping behind in installing median barriers, while surpassing speed targets.

A Road to Zero target aims to have 1000km of median barriers by 2030, but is projected to fall short by half.

Meanwhile, the agency has exceeded its target of assessing speeds on 10,000km of road.

AA Road Safety Spokesperson Dylan Thompson told Kate Hawkesby 100km of barriers should be installed every year.

He says they didn't think it was a hugely ambitious target when it was set, but they haven't managed to get close to it so far. 

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