Between 2016 and 2020, the New Zealand government built an extension of the Christchurch Northern Motorway as a part of its Roads of National Significance programme, at a cost of $240 million. This created a more direct and faster transport route between QEII Drive in Christchurch and the Chaneys Interchange just to the north of Belfast. As $240 million would have gone a long way towards creating a passenger rail service from Christchurch all the way to Rangiora on the existing Main North Line corridor, the decision to proceed with a motorway over such a short distance at this cost (6.5 km, or about $37m/km) was and remains controversial. To build a rail suburban network, as advocated consistently on this blog, the existing corridor would probably have to be doubled all the way to Rangiora, including the Waimakariri River Bridge, which would be a significant part of that cost in and of itself. New stations would have to be built at nearly every location, since historical infrastructure is generally in poor condition or non existent. The last time Ecan did a serious study back in 2014, the existing bus service passenger numbers between Christchurch and Rangiora were quoted at around 500 a day, but the breakdown of these is unknown. 500 passengers a day could possibly support one train each way at peak times (2 trains per day) as long as everyone was travelling at peak times. In reality of course, the bus service passenger numbers are spread throughout the day, and more info on the breakdown of density is needed.
The opening of the motorway has led to two new Metro bus routes – 91 Rangiora/City Direct and 92 Kaiapoi/City Direct. The 91 route is shown below and analysed in more detail.
The Route 91 bus runs from Rangiora to Christchurch as an express service utilising almost the full length of the Christchurch Northern Motorway. As there are no stops on the motorway itself, passenger embarking/disembarking points are limited. The Metro map shows three stops in Rangiora itself, after which the bus runs non-stop south via Lineside Road to its interchange with the CNM, continuing without a pause to Cranford Street in Christchurch and then following local streets until it reaches a stop on Manchester Street north of Kilmore Street, followed by the Manchester Super Stop and then the Bus Exchange. It terminates at the Christchurch Hospital Super Stop. There are therefore in total less seven stops on the whole route and these are entirely at both ends, with no intermediate stops. This enables the bus service to operate rapidly (express speed) between the two locations. The Route 92 Kaiapoi/City Direct service is similar except that it originates in the centre of Kaiapoi and uses Main North Road (the old highway before the first part of the CNM opened in 1967) to reach the CNM at the Tram Road interchange. The rest of its route is identical to Route 91. At this time, it is unknown what speed the buses are capable of operating at on the motorway but it is assumed this will be 100 km/h.
Timetables for Route 91 show that it operates only Monday to Friday during the morning and afternoon peaks, with four southbound-only services in the morning and five northbound-only services in the afternoon. This requires four buses for the morning timetable, due to the close spacing of the services (30 minute frequency) and probably four buses for all five afternoon services for the same reason (it appears the frequency would allow one bus to return empty to Christchurch and run two services in total). CTB does not know but assumes that buses are stabled overnight in Rangiora at the end of each day for the next day’s inbound services and stabled in Christchurch during the day between the inbound and outbound services. The Rangiora stops each correspond with a park-n-ride facility for motorists whilst most of the Christchurch stops are high capacity locations: two superstops and the bus exchange. The Kaiapoi service provides the same number of services each way daily but due to shorter runs it might be possible to utilise fewer buses; again there is the possibility that buses are stabled locally overnight. Two of the stop locations in Christchurch are park-n-ride facilities. Typical timings provide 50 minutes for the Rangiora service and 40 minutes for Kaiapoi.
The services were both introduced in January 2021 and supplement the existing Route 1 service which runs between Christchurch, Kaiapoi and Rangiora with stops all along the entire route. Route 1 has its own express services, five during the morning peak (southbound only) and seven during the evening peak (northbound only). The express service times on Route 1 between Rangiora and Christchurch are around 75 minutes and from Kaiapoi, around 45 minutes. It can therefore be seen that there is only a small benefit for Kaiapoi passengers in using the express bus via the motorway if the bus is able to keep to time; it is somewhat likely delays will occur on Route 1 in particular during peak times because of congestion on Christchurch streets, although Main North Road is being improved with bus priority measures. Rangiora passengers see a lot more benefit assuming Lineside Road is not congested during peak times. It is possible that the significant increase in Rangiora times for Route 1 is due to picking up and dropping off a lot of passengers between Rangiora and Kaiapoi as well.
This post is being written primarily around an article in the Christchurch Star on 26 July, which coincides with a CTB OIA request for passenger numbers from Rangiora and Kaiapoi. The article stated there were 3816 passengers on the Rangiora route in May, and 2380 on the Kaiapoi service. An important point is there is no apparent differentiation between inbound and outbound passengers, or in other words it isn’t clear whether the numbers were combined for both directions. The month of May had 22 weekdays, so these work out to an average of 173 per day on the Rangiora service and 108 per day on the Kaiapoi service, or a combined total of 281 daily across both services. CTB NZ has requested June numbers of boardings of all services at Rangiora and Kaiapoi, so this will enable some of these questions to be answered.
Regardless, 281 passengers a day on an express bus is not enough to run a train service, which needs to carry a lot more passengers per service to be viable. Some campaigners claim it should be possible to use small trains e.g. DMUs with a passenger capacity of 50-100 to substitute more or less directly for buses. However, rail services face significantly higher operating costs than a bus network, due to the need to provide more infrastructure and operating staff, and therefore need to carry more passengers to overcome differences. For example, present generation DMUs have two staff, compared to one for a bus service, unless it becomes possible in future to have a DMU that just has a single crew member. It is therefore an accepted reality that rail services need to be focused on routes that can persistently generate higher passenger counts. 281 passengers spread over multiple services really only comes to at most a busload (around 50) per service, which is unlikely to be economical. If it turns out that the counts are combined both ways, the numbers will be shown to be even smaller.
The picture of the total bus services in North Canterbury will become clearer when the full breakdown of passenger numbers if available from CTB’s OIA request but at present these express services would not indicate a clear pathway exists for rail passenger services between North Canterbury and Christchurch.