Higher speeds lower productivity: what the data shows crash delays really cost Auckland
Timothy Welch, Senior Lecturer in Urban Planning, University of Auckland, Waipapa Taumata Rau Another morning, another crash on one of Auckland’s major roads. Traffic isn’t moving. Drivers sit in their cars rehearsing reasons for being late again. Radio hosts offer the usual advice: leave earlier and find an alternative route. It happens so often we barely notice anymore. But the costs add up fast, and they’re far bigger than a few delayed meetings. Auckland had 34,628 reported crashes between 2022 and 2025. The “road toll” conversation typically stops at the obvious costs: injuries, deaths, emergency response. But it misses a lot. A new analysis puts the true figure at NZ$9.23 billion over those three years (roughly 2% of Auckland’s $157 billion economy), including nearly $200 million that never enters the policy debate. Transport agencies already put dollar figures on crashes. The New Zealand Transport Authority (NZTA) uses official methodology covering the usual: medical bills, lost productivity, property damage and the statistical value of a life. One fatal crash amounts to $15.2 million. But buried in the technical reports is an additional cost category that most policy discussions ignore: network disruption. False economies Crashes on major roads hit more than just the people involved. Thousands of other drivers get caught in the delays that spread across the network. Traffic engineering consultancy Flow Transportation Specialists recently worked out these network delay costs for Auckland Transport for the first time. Using GPS travel time data and traffic counts, researchers tracked how crashes create congestion that extends far beyond the crash scene and persists long after vehicles are cleared. A multi-vehicle crash on Auckland’s motorway network generates between $1.4 million and $3.5 million in network delay costs. Even a serious crash on an arterial road can cost $26,000 to $37,000 in lost time across all affected road users. When applied across […]
