Modelling the benefits of an inland port for Christchurch

Abstract

This research models the effect of a future inland port for Christchurch. This facility is not currently planned but is mooted as a means of reducing the vehicle-kilometres travelled (VKT) by heavy goods vehicles. This could lead to multiple environmental and social benefits by reducing the externalities caused by the transport of container freight. These include reduced road congestion, reduced fuel and energy use and lower CO₂ emissions. This is in addition to economic benefits such as further opportunities for the hubbing of goods and for the optimisation of network systems, improved service levels for freight operators and greater consolidation of freight activities. This facility is proposed for the Islington area due to its strong road and rail links, the benefits of having a second distribution point across town from the port, the large numbers of transport and logistics operations based in this area and also the limitations on the use of land arising from the noise of the nearby International Airport. In this research real world data on container movements within Christchurch were gathered from container transport operators. As a means of accounting for the variance in activity between weeks, these data were collected for both an average week and a busy week (self-selected by operators). These data were then coded and entered into an Excel spreadsheet to establish a baseline against which two potential future scenarios could be compared. These scenarios are an inland port only scenario where containers are distributed entirely out of an Islington inland port and a hybrid scenario where containers are distributed out of both Islington and the existing CityDepot located in Woolston (albeit used in a greatly expanded capacity). By altering the spreadsheet to take into account these alternative distribution structures it was possible to compare the vehicle-kilometres travelled (VKT) in each of the three scenarios studied (the baseline scenario; the inland port only scenario; or the hybrid scenario). This includes the assumption that the containers would be moved to the inland port by rail and then distributed by road. Using these VKT figures in conjunction with those for rail fuel usage calculations were then conducted to determine the impacts of these scenarios on congestion, fuel and energy usage and CO₂ emissions. This analysis has shown that while the inland port only scenario sees considerable savings in vehicles-kilometres travelled (17%) and overall congestion (12.4%) it will actually increase energy usage and the resulting externalities due to the large number of across town rail journeys- leading to a negative environmental outcome over the baseline. The hybrid scenario, however, not only results in larger savings in regards to VKT and congestion (both 42 %) but also sees a 23% reduction in fuel, energy use and CO₂ emissions. As such this is the recommended scenario assuming that the issues of cost, stakeholder buy-in and supply chain communication can be overcome.