04How public transport use differs across Wales and why

Public transport ridership varies greatly across Wales. These differences are seen both between urban and non-urban areas, and between different cities. This section compares the performance between different places and highlights the factors that drive those differences.

Commuting patterns mostly differ between Cardiff and the rest of Wales

The two censuses conducted before the pandemic (2001 and 2011, see Box 1 for further details of what they mean for 2023) show at least two features of commuting patterns in Welsh cities and non-urban areas. First, public transport commuting in Wales is similar between the regions of Wales with the exception of Cardiff. The capital is comparatively less reliant on private vehicles (noting they are still the main mode of transport). Within public transport, the role of rail is relatively minor outside the capital.

Figure 6 shows that commuting patterns remained mostly unchanged between 2001 and 2011, except for Cardiff, where there was some substitution from driving to rail and active travel. In line with the findings from the previous section, the share of commuting by bus fell slightly.

There evidence is unclear whether driving has reduced in Wales since 2011

Although the 2021 Census (due to the pandemic) does not provide conclusive evidence of whether the share of commutes by driving in Cardiff continued to fall, other data sources suggest that this does not seem to be the case. The number of kilometres driven by cars and taxis – not necessarily commuting flows – kept rising everywhere, especially in Cardiff. In the capital, the number of kilometres driven increased by 19 per cent between 2011 and 2019 (Figure 7). One potential factor behind this increase is the emergence of ride-hailing apps in the Welsh capital since 2016, which frequently compete with all modes of transport.¹⁶ This is a reversal of the trend observed in the years before 2011, during which the number of kilometres driven on Cardiff’s roads was falling while driving in other Welsh cities was rising.¹⁷

However, the Ask Cardiff Survey suggests that commuting by car has been falling in Cardiff. By the end the 2010s, it suggested that around 50 per cent of commutes were by car.¹⁸ It is not clear why there is a difference in the findings.

Public transport usage mainly depends on how competitive it is against driving

Analysing the main factors that make public transport attractive relative to other forms of transport helps explain these differences and what this means for public transport policy. Two main factors influence ridership (summarised in Figure 8):

1. ‘Public transport accessibility’ (see Box 3 for methodological details) to the main economic centre for each city: this is a function of a) the network size at peak times and b) the people living within those areas (residential density).
2. Relative competitiveness of public transport compared to driving: this is a function of a) job concentration in the main economic centres (i.e. polycentric vs. monocentric patterns of jobs) where public transport is easier to plan and operate in monocentric economies and b) the relative cost of public transport against the car, both financially (the price of each mode) and in terms of time taken (road congestion and frequency and reliability of public transport).

What follows uses this model to assess the determinants of public transport accessibility in Welsh cities relative to UK and European peers, which have been chosen based on their similarities in population, industrial structure and topography. There are other relevant variables, such as public transport frequencies, speeds and fares, which will not be directly measured due to data limitations.

Public transport accessibility is lower in Welsh cities but its factors seem to vary

Factor 1: Public transport accessibility: network size and residential density

Public transport accessibility (which is a function of the size of the network and residential density as explained in Box 3) to their main economic hub is mostly lower in Welsh cities than in their better-performing peers (the selected peers are detailed in Table 8.) For example, Figure 10 shows that 41.7 per cent of Cardiff workers can access its main economic centre in 30 minutes by public transport, compared to between 57.2 per cent (Edinburgh) and 81.9 per cent (Brighton).²¹ This underperformance holds across the other Welsh cities too. The share of workers within 30 minutes of the main transport hub is lower in Newport and Swansea than in Sunderland, Plymouth or Hull, while Wrexham, is the best performing Welsh city, it trails Gloucester.

As Figure 8 sets out, this is a function of two factors: the size of the network and the density of residential development.

Factor 1A: Network size

The size of the public transport network seems to be a constraint for Cardiff and Swansea, which have public transport networks smaller than most of their peers. Reading’s catchment area in 30 minutes by public transport is almost twice Cardiff’s size. And Sunderland (which includes parts of Tyne & Wear Metro) and Hull (which does not have a mass transit system) outperform Swansea.

In contrast, Newport and Wrexham’s public transport networks (measured as their areas covered within 30 minutes) are not smaller than most comparable to their peers, despite their broader poor accessibility performance previously shown. Wrexham’s network is almost as large as Gloucester, while Newport only underperforms Sunderland.

Factor 1B: Residential density in well-connected areas

Instead, the challenge for Wrexham and Newport in particular (as well as Swansea) is that they do not have large shares of their populations living in this network catchment area. Figure 12 below shows that lack of residential density in well-connected areas is a common feature of Welsh cities when compared to their respective peers. Cardiff is the best performer on this measure but all perform poorly relative to their comparators. In contrast, Brighton’s relatively small public transport network (as shown in Figure 12) is partially compensated by having a lot of residents living within the best-connected areas of the city (Brighton has 2,641 workers per km² compared to 1,724 workers per km² in Cardiff).

Factor 2: Public transport competitiveness compared to the car – job concentration and car congestion

The structure of the economy and the influence of this structure on job location also affect the viability and performance of public transport. Outside of Cardiff, both the concentration of jobs in urban centres and the congestion in the cities is comparatively low.

Factor 2A: Job concentration and industrial structure

Cardiff has a much greater share of its jobs located in the centre than other Welsh cities (Figure 13). This means that many more commutes finish in the same place, creating congestion and making commuting by public transport relatively more attractive and commuting by private transport more difficult.

Cardiff’s share of jobs in its centre compares favourably with its peers, but this is not the case for the other cities. This dispersion of jobs results from their relatively high share of jobs in the non-service economy, in sectors like manufacturing, mining, and storage, that require large and relatively cheap space or locations close to natural assets (see Figure 14). In contrast, Cardiff’s economy has a high concentration of knowledge-intensive exporting services (e.g. media, marketing, design) which have shown an increasing preference for city centre locations in recent decades.²²

Factor 2B: Car congestion

Higher job concentration creates car congestion at peak times. Provided this congestion does not affect public transport (e.g. through bus lanes), this makes public transport comparatively more attractive. Congestion data from INRIX support this hypothesis: Cardiff is the only Welsh city where congestion is on a par with peer cities. Swansea, Newport and Wrexham have much smaller congestion problems than both Cardiff and their peers (Figure 15).

Summary: Cardiff’s underperformance drivers differ from those in the remaining Welsh cities

Welsh cities trail their peers in terms of public transport accessibility. The reasons behind this differ between each city. Cardiff’s underperformance seems to be explained by a combination of a relatively small public transport network with lower density in the best-connected areas of the city. Policies designed to boost public transport ridership should focus on expanding the public transport network – connecting more areas to central Cardiff – and densifying well-connected neighbourhoods.

Improving public transport accessibility to the centres of the other cities would naturally increase commutes done by public transport. But their economic structure and job concentration will likely limit the increases in ridership as the car continues to hold the edge. This means that a different approach to boosting public transport ridership will be required – one that reflects the lower density nature of both its residents and its jobs. Table 2 summaries these findings.

The next section analyses each city in more detail and sets out successful policies from elsewhere that can help shape their respective public transport systems.