The Problems with Dublin's Luas Lines

Tuesday 04 October 2024 - Adam Ross - Transport Planner at Metro Dublin

Dublin's two Luas tram lines, while successful at first, now struggle to meet growing demand. Issues like overcrowding, slow speeds and capacity limitations highlight the need for improvement. I argue that these lines should have been metro lines from the start and that upgrading them to metro systems is a necessary investment despite the higher costs, to ensure they can handle future growth effectively.

Luas Map

Too many stops
Having too many stops on a tram line can be problematic for several reasons, particularly regarding travel time and stop redundancy. First, frequent stops slow down the overall journey, as trams must decelerate, stop, and accelerate repeatedly, significantly increasing travel time for passengers traveling longer distances. The Luas has all these problems. This can make the lines less efficient compared to other modes of transport, such as the Dart, discouraging ridership.

Additionally, if stops are placed too close together, they may become redundant, offering little value to passengers while increasing operational costs. The best examples of this are Fatima and Rialto stations on the red line, as well as Stillorgan and Sandyford stations on the green line which are spaced only around 500m apart, which is not good when trying to create mass transit, especially since these areas aren’t even part of Dublin city centre. Redundant stops can also cause congestion on the line especially during peak hours, as more frequent boarding and disembarking add delays; This also limits how frequent the trams can run.

​To optimise the system, tram stops should be spaced to balance accessibility and speed, ensuring that the network remains efficient and appealing for users. For example, people living in Cherrywood would need to travel over 20 stops in around 40 to 60 minutes to get to the city centre, and people travelling from Tallaght or Citywest to the city centre on the red line would have to travel for a minimum of 40 minutes. Whereas a metro or Dart would take around half that time assuming it were underground and didn’t have as many sharp turns requiring trains to slow down substantially, which I’ll talk about later. This isn’t terrible and is still faster than getting the bus most of the time but could be majorly improved if the line were a metro line even from Sandyford onwards if Metrolink ends up being extended and replacing the green line up until that point.

Very Close Luas Stop Spacing which makes sense for a tram line in the city centre although results in less than jogging speed on average which is inconvenient for people just trying to get to work or get home quickly.

Luas Tram

Stillorgan and Sandyford stops also placed unnecessarily close together at only around 500m apart, equivalent to a 5-minute walk for most people, not to mention all the sharp turns added that slow down tram speed even further

Six stops on the red line all within 2.7km near but not in the city centre, not much less than a bus route.

Not enough capacity (especially the red line)
Trams are limited in their ability to meet the demand of a metro system due to their smaller capacity and infrastructure constraints, which is easily visible on both Luas lines during peak hours, especially in the city centre. The Luas lines partially operate on surface streets, often sharing space with other vehicles, which limits their size and the frequency of services they can offer.

Unlike metro systems, which run on dedicated tracks underground or above ground, trams have shorter carriages and lower passenger capacity, making them unsuitable for handling large volumes of passengers during peak hours, which neither line but especially the red line is managing to do. While the green line’s capacity has been expanded throughout the years to 55m long trams, its capacity is still very constrained as the line has the demand of a metro as seen by the overcrowded stations. The red line has it even worse as its trams are only 40m long with overcrowding not too different to that of the green line, and the platforms can’t really be extended anymore due to constraints of a few of the stations on the line and their locations.

​Additionally, the trams usually have to stop at intersections and traffic lights, reducing their efficiency and further limiting the number of passengers they can transport quickly. Metro systems, with their larger trains, high-frequency services, and grade-separated tracks, are better equipped to handle high demand, making them more effective for areas that demand that kind of service and capacity even if not within the city center.

Longer travel times than necessary
Tram lines are generally slower than metro lines due to several key factors related to their operation and infrastructure. One reason for this is that trams typically run on surface streets with sharp turns not being uncommon, where they must share space with cars, pedestrians, and other forms of traffic. This results in frequent stops at traffic lights, intersections, and pedestrian crossings, which causes delays and annoyingly slow speeds for commuters.

In contrast, metro systems operate on dedicated tracks, often underground or elevated, avoiding traffic congestion and enabling faster, uninterrupted journeys. Trams also make more frequent stops, often spaced closer together to serve local areas, which increases travel time as the vehicle must decelerate and accelerate repeatedly. Additionally, trams usually have lower top speeds compared to metro trains, further contributing to their slower pace.

​In addition, running trams on street level is much less safe than an underground metro below the city of Dublin due to potential collisions with traffic and pedestrians, especially since Dublin is such a car dependent city. These factors combine to make the Luas lines less efficient for long-distance travel, adding to overall travel time compared to the faster and more direct metro systems, which is why I believe metro lines under the city would be a much better investment despite the much higher cost of tunnelling as opposed to street level tram tracks and stations.
 
In conclusion, while Dublin’s Luas trams offer valuable local connectivity and meet travel demand to an extent, they are inherently slower and less capable of handling high demand compared to metro systems. The frequent stops and street-level operation of the Luas lines add to travel time, and their limited capacity makes them unsuitable for accommodating the large overcrowding volumes of passengers that try to use the lines daily. In contrast, metro systems, with dedicated tracks, fewer stops, and higher speeds, are more efficient for rapid, high-capacity transport, especially in densely populated urban areas. To optimise its public transport in these areas, Dublin should consider upgrading both Luas lines to metro lines as their far better speed, efficiency, reliability and capacity would be far better equipped suit the areas that the Luas lines run along than the Luas lines themselves.