This paper summarises research carried out to determine the safety implications of flush medians at 50 Auckland City sites for which at least five years of recorded crashes were analysed. The before and after crash study showed that large crash cost savings have been achieved with flush median implementation despite small overall savings in frequency. Flush medians decreased fatal, serious and non-injury crashes while increasing minor injury crashes at the study sites. Crash types were affected differently by flush medians, with major savings seen in turning versus same direction, 'pedestrian' and 'loss of control' crashes and large increases seen in some rear end crashes and the turning crashes. Crash reductions were observed to be greatest during night-time periods, with increases in crash costs observed in peak periods. Both narrow and wide medians produced crash savings highlighting the benefit of installing narrow medians where carriageway width restrictions apply. (a) For the covering entry of this conference, please see ITRD abstract no. E210413.
Samenvatting