In 2017 we developed a system dynamics model to study inter-regional freight and traffic flows in the Auckland–Hamilton–Tauranga triangle. Here we extend the model northward to Whangarei in order to incorporate Northport. This enables us to provide an order of magnitude estimate of how many truck movements might be required to transport freight between Auckland and Northport, if most or all of the exports and imports that currently pass through Ports of Auckland were to enter and leave New Zealand via Northport instead.
Excluding the ALPURT to Wiri route, our results suggest that although there is probably enough road space per se to accommodate the extra trucks without significantly affecting travel times, their lower average speed would reduce the speed of other vehicles – and thus increase travel times – if there are insufficient opportunities for overtaking. Most of the road north of Pūhoi is one lane in each direction.
Keywords: cost-benefit analysis, destination management, road infrastructure, South Island New Zealand, visitor attractions, tourism, tourism flows model