Dublin needs buses and light rail, not just one or the other,writes Tom Manning, in response to James Nix's recent critique of Luas
On Monday, February 2nd, the Lord Mayor of Dublin laid the last section of rail track for Luas. Cllr Royston Brady pointed out that the Luas stop at Connolly will be the hub linking light rail with DART and mainline services.
Irish Times readers may not be aware of this event, which was not covered in the paper. Instead readers were offered a poorly researched article by transport researcher James Nix, a persistent critic of the Luas project and of trams generally. It is a little disappointing that this trenchant and inaccurate analysis was presented in isolation.
Mr Nix's article began by reporting that the Tallaght/Connolly line will open at the end of June and the Sandyford/St Stephen's Green line in August. If he had bothered even to make a quick phone call, he would have realised that he got the sequence wrong - it's the other way around.
However, it is in his analysis of the economics of light rail where things get seriously confused.
The assertion that Luas is "grossly uneconomic" is not supported by any serious analysis. The powers to implement Luas were granted by the then minister for public enterprise following public inquiries that analysed the project in great detail. Internationally respected consultants Steer Davies Gleave concluded that the line from Tallaght to Middle Abbey Street would produce a significant and healthy economic return to the State.
This appraisal was undertaken at a time when congestion was not as acute as it is now, so the economic case for Luas has been strengthened.The Government's later decision to extend the service to Connolly, thus improving the interchange with bus services at Busáras and rail at Connolly, further strengthened the economic case for Luas.
Quality Bus Corridors (QBCs) have made a significant contribution to easing the appalling congestion in the greater Dublin area.
However, the problem of congestion will be addressed not just by one mode of transportation but by a combination of bus and rail. It has been shown in most modern cities that rail-based transport can move commuters in much higher numbers than buses can on their own. Buses can offer a higher degree of flexibility for smaller numbers of passengers.
It is regrettable that the complementary strengths of bus and tram, which work so well in other countries, were presented in The Irish Times as a theoretical transport "blood-sport" exercise with tram pitted against bus.
Mr Nix's pocket calculator analysis of capacity comparison does not add up. The capacity of a 30-metre tram is 235 persons, and not 207. The capacity of a 40-metre tram is 310. Running a tram every five minutes means there will be capacity for between 2,800 and 3,700 passengers in each direction. Thus, in the morning peak, there will be as much capacity out to Tallaght and Sandyford as there is in to the city. Not true for buses, unfortunately.
Meanwhile, the bus capacity is overstated. The normal load capacity of a typical Dublin double-decked bus is 88, not the 98 claimed. To match the capacity of Luas on the Sandyford line, for example, buses would need a frequency of one every 85 seconds in both directions. The likelihood of this is remote.
It is estimated that the number of passengers past a single busiest point is actually 2,500, far fewer than the possible capacity given by Mr Nix. Reality intrudes on the theoretical. Commuters know well that buses bunch together and start to delay other buses. The front bus is full and the trailing bus has spare capacity. Also, buses generally only operate one door, which causes delays. This will not apply to trams. It is for these and other reasons that cities decide to adopt rail-based transport when passenger numbers increase beyond a certain level.
The actual capacity of a QBC over a complete route is much lower than claimed by Mr Nix. In fact there is no existing example in Dublin of any QBC achieving the capacity claimed for QBCs generally. A dedicated bus-way (for buses only) would be needed to hit these figures. It is true that some cities in developing countries, such as Curitiba in Brazil, achieve high bus capacity by using such bus-ways.
However, even these cities are keen to convert the bus-ways for rail use.
While the capital cost of light rail is indeed far higher than the cost of QBCs, this is not so of relative operating costs. Recent research in London (TAS Partnership, January 2004) suggests it is three times more expensive to run buses than tramways over a full operating year when carrying 3,750 people per hour in each direction. Considerable operating cost savings can be made by choosing light rail technology.
The real advantages of light rail over standard bus services or QBCs have not been explored. We would have been happy to outline these if we had been asked. Firstly, Luas offers significant journey time savings over bus services along both routes. Luas is estimated to take 38 minutes from Tallaght to Abbey Street all through the day, and 22 minutes from Sandyford to St Stephen's Green all through the day.
This level of service cannot be matched by even the best existing QBC. Luas will also offer a punctual service, with trams every five minutes at peak hours and less frequently off-peak. Trams are also more reliable than buses because of the reduced risk of delay through interaction with other road users.
Mr Nix's final comment is grossly unfair, as it suggests that Luas will not be sympathetic to other street users. This is nonsense. Luas is being designed as a highly accessible, open system with pedestrians sharing the alignment with the trams in the city centre areas. All vehicles offer low-floor access, making it easy for parents with strollers to board through all doors, and for elderly people not to have to negotiate a step to get on the tram.
The system will offer more than 2,000 park-and-ride spaces at key locations, and cycle parking facilities are being provided at certain places along the routes.
These facilities will make Luas an integral part of the transport environment. Integration with all road users will be the key to its success. It makes little sense to argue whether buses or light rail is best. Dublin needs both high-performance light rail and a continuation of the successful QBC network that has been implemented in recent years.
Tom Manning is public relations manager of the Railway Procurement Agency