The editorial on 26 August explained why it's time for Wellington to have another look at light rail. It also put its finger on the central problem: cost. Can Wellington afford to make the investment?
As candidates for Greater Wellington Regional Council, we sought advice from a range of sources, to inform our position on the future of public transport in Wellington. Here we set out the evidence which led us to conclude that:
# light rail is an esential part of the future transport mix;
# planning needs to start now, with a view to having light rail operational within 10 years; and
# in the mean time, we must continue to make improvements to the bus system.
Costs are the worry for light rail. Cities overseas use a "no-frills" approach. This includes laying tracks in existing roads, avoiding costly tunnels and flyovers; having widely-spaced stops close to major destinations to improve travel times; and buying uncustomised off-the-shelf vehicles. Wellington can do this too.
We also learned that off-the-shelf light rail vehicles, available today, can operate without overhead wires. These are battery-powered, use regenerative braking to recharge as the vehicle slows down for stops, and complete recharging while the vehicle is stopped.
The estimated cost from the Railway Station to the Airport is $450–650 million, depending on the route, made up of:
* $40 million per route kilometre (including vehicles), based on the average cost of 11 recent French light rail projects;
* additional costs for tunnels, at the rate per metre given in the 2013 Public Transport Spine Study; plus
* a further 20% allowance for studies, design and contingencies
The largest single cost of public transport, whether buses or light rail, is the driver. A modern light rail vehicle in Wellington could carry as many passengers as 6 or 8 buses, and in the central city would run at an average speed of around 15 km/hr, including stops. Six buses would be struggling to manage half that speed, with labour costs at least 10 times higher.
We agree with the Minister of Transport that self-driving vehicles will reach commercial scale in 5 to 7 years. We therefore expect that light rail vehicles in Wellington will be self-driving. Current autonomous light rail systems (fully segregated from other traffic) operate with zero rate-payer subsidy. This is our aim for Wellington.
But won't self-driving cars make light rail obsolete? Cars (whether self-driving or not) are good at enabling travel to a diversity of destinations from a diversity of origins -- they are the friends of urban sprawl. Cars are not good when a lot of people want to end at the same destination or start from the same origin -- e.g. the city centre.
This is why larger capacity vehicles are needed -- you need fixed-link segregated public transport, either full guided bus, light rail or heavy rail to carry the required numbers in an efficient transport system. In fact, light rail would work very nicely with self-driving cars, as they provide complementary services. Wellington needs multiple transport modes to meet its transport needs.
What about the alternatives to light rail?
Wellington's golden mile already carries up to 6000 bus passengers an hour during peak times. However, a widely-used maximum for quality bus routes (explained and recommended in the 2011 Bus Review) is 60 buses an hour, compared with up to 140 an hour at present. A major cause of Wellington's current bus problem is the badly overloaded route.
The practical capacity for a quality bus route with predictable journey times is about 3500 passengers an hour: barely half existing demand. As Friday's editorial said, Wellington needs dramatically improved public transport, with potentially dramatic benefits. Light rail needs 3000 passengers an hour to be economically viable -- half the existing demand.
How about BRT (Bus Rapid Transit)? Wellington's planned BRT is more usually called BP (Bus Priority) and offers minimal improvement over regular buses. Even with BP, the golden mile cannot carry more than 6000 passengers per hour. Real BRT needs 4 dedicated lanes through the central city, with flyovers at busy junctions -- twice as much space as light rail.
A 4-lane highway to the Airport? Light rail would have 3 times the capacity and cost half the $1bn projected for a 4-lane highway. Unlike car travel, people travelling by light rail enjoy a congestion-free journey. As demand grows, adding modules to existing vehicles or increasing the service frequency adds capacity.
Wellingtonians want a range of quality transport choices -- public transport, active transport (walking and cycling), and private transport. Achieving this requires a joined-up view of transport issues, across all transport modes.