Mother Nature gave the Wellington rail system a quite of a battering last year through multiple earthquakes and major storms. The major storm that hit on the night of 20 June was the one that did the most damage when it washed out the sea wall protecting the rail line that serves the Hutt Valley and the Wairarapa between Ngauranga and Petone leaving tracks dangling in the air. Kiwirail said the damage was unprecedented. The impact of the outage was felt throughout the Wellington transport system as people who usually caught the train needed to look to other methods of transport. It took almost a week to get the rail line restored with services resuming on the morning of 27 June.
If there was one positive to come from it, its that it gives a chance to study what the impacts of the outage and that’s exactly what the Ministry of Transport have done in a report released late last year.
Extreme events and disruptions to our every-day lives give us a chance to probe how we react in different circumstances, and consider how we can better react in the case of similar future events.
The storm on the night of Thursday 20 June 2013 severely affected Wellington’s transport network, with both immediate and flow-on effects for commuters in the region. Of particular significance was
the damage done to the Hutt Valley rail line, and the consequent disruption to passenger rail services for the six days following the storm.
This project surveyed 1,072 Wellington commuters to assess several impacts on Friday 21 June, Monday 24 June and Wednesday 26 June, including:
- the extent to which disruptions to the transport network (in particular the Hutt Valley rail line services) affected the time it took commuters to get to their destination
- how commuters changed their travel behaviour to respond to the network disruptions
- the extent to which communications by transport agencies (including radio, email and text messaging) may have influenced the behaviour of commuters.
And here’s a summary of what the study found.
- The closure of the Hutt Valley rail line put significant pressure on the road network. Delays for commuters were most severe on the Monday following the storm. Traffic on State Highway 2 was severely congested, with morning peak hour conditions lasting two hours longer than usual
- 80 percent of Wellington commuters from the Hutt Valley and Wairarapa experienced a longer than usual trip
- 32 percent of them experienced delays of over an hour
- the severity of commuter delays lessened over the week, with the number of commuters from the Hutt Valley and Wairarapa experiencing delays of over an hour halving by Wednesday 26 June
- traffic delays were slightly less severe on Friday 21 June. This may have been due to 27 percent of commuters (surveyed across the region) not travelling to work on the Friday. By Monday 24 June this figure dropped to just 4 percent
- on Monday 24 and Wednesday 26 June, roughly 45 percent of the typical Hutt Valley train commuters opted to drive themselves or be driven to work in a private car, and roughly 45 percent chose the train and bus replacements
- communications by transport agencies were effective, with 75 percent of people surveyed aware of transport delays before they headed to work on Friday, and over half of these people altering their travel plans to respond to conditions.
Research undertaken as part of this project estimated that the economic impacts of transport disruption resulting from the storm was between $12 million and $43 million. This included $5.3 million in cost to local and central government agencies who responded to disruptions and damage on the transport network, $5.3 million loss in value of travel time and between $2 million and $32 million reduction in outputs.
There’s a few interesting points in here. The first is day of the outage (red) compared to same day the week before and after.
The severe congestion probably helped to ensure that those who were previously using trains went back to doing so once the rail line was up and running again. This is the patronage from the Hutt Valley line surrounding the outage and you can see it bounced back to normal the following week.
Probably the most interesting part is the assessment of the economic impacts of between $12 million and $43 million depending on how it’s calculated. Some of those costs – like the $5.3 million in repair works – are unique to the outage however the same amount again is simply due to the travel delays caused by the mode shift and ensuring congestion. This might not sound like much but consider that it is just for four working days so equates to about $1.3 million per day. That helps to give us an idea as to just how much impact the rail network in Wellington is having on congestion relief.
My understanding is that the Hutt Valley line carry’s roughly half of the patronage on the Wellington rail network while the rail network itself only accounts for about 6% of all journey to work trips. Imagining for second that someone decided to close the all of rail lines in Wellington we can probably assume that similar travel delays would occur throughout other parts of the road network. Even just using the figure of $1.3 million per work day extrapolated over a typical year (~250 working days) would see travel time delays add up to over $320 million per year. By comparison the entire system only costs something like $80 million to run and that’s before passenger fares are taken into account.
Of course there would be a lot of other things that would need to be taken into consideration and the costs above are just very quick calculations but it does go to show that while the rail network might only play a small part overall, it does play a significant one.