Traffic congestion is costing us. Ibec warned about its impact on businesses this week – and anybody who lives in an Irish city knows all about it. The evidence suggests not only that the cost is growing, but also that it is changing the way many of us organise our day. Add sustainability and the drive to cut the number commuting by car to the mix and you get a huge policy challenge. What can economics tells us about the costs? And what can the data tell us about how congestion patterns in Ireland are changing the way we live? There are a number of key policy challenges.
1. Congestion – the theory
Traffic congestion imposes costs on the economy – and on our lives. Measuring this is not straightforward and putting a cost on it is even more complicated. But the cost in Ireland now – notably in Dublin but also the other major cities – is certainly significant and rising.
Congestion imposes a range of costs. The most obvious one is on people’s time – and also to businesses in terms of delayed delivery. But there will also be a higher level of pollution, increased cost of fuels for drivers and the dislocation caused by uncertain journey times. We will see below the striking impact this is having on M50 traffic in Dublin and N40 traffic in Cork. And then there is the point identified by Ibec – the impact of congestion, along with housing and inadequate public transport, on the ability of companies to attract and reward employees. This is the competitiveness impact.
Measuring when a road gets too congested is not easy. Various estimates have been made over the years relating to the cumulative delay in journey times for commuters, for example.
This is the congestion tipping point and many of our urban roads are at or well beyond it
A detailed study by the Irish Government Economic and Evaluation Service (IGEES) for the Department of Transport in 2017 – The Costs of Congestion – An Analysis of the Greater Dublin Area – took another approach. It looked at the optimum capacity of the road – the amount of traffic a road could take before the volumes caused such a slowdown that there was a decrease in the total flow. It then estimated that at anything above 80 per cent of this level,“aggravated congestion” (the kind that leads to costs) would apply. At this level its data shows, speeds start to fall significantly. and costs start to mount significantly. This is the congestion tipping point and many of our urban roads are at or well beyond it.
2. Congestion – the cost
The Department of Transport study put the cost of congestion, in terms of lost time, at €358 million in 2012 – the last year when full data was available – but said this could rise significantly to over €2 billion by 2033.
International data confirms that the cost per driver can easily approach €1,500 a year, or more, in congested cities
In 2012, traffic volumes had dropped from their pre-crash peaks and have since recovered strongly – meaning the cost will have risen. A back of the envelope calculation – on the basis of the figures – suggest that the cost of Dublin traffic now could be in around €500 million. The analysis did suggest that costs could rise much more sharply after 2024, unless action was taken, as more and more roads passed the key tipping point for longer parts of the day. It said that the worst traffic is now on the roads inside the M50 and leading on to it, but that the roads immediately outside the M50 could face significant additional congestion in the years ahead.
International data confirms that the cost per driver can easily approach €1,500 a year, or more, in congested cities. Putting firm figures on this is very difficult, but many studies confirm that the costs are significant and can have a significant wider economic and social impact.
International data – albeit based on a range of different sources and methodology – indicates that the Republic ranks relatively highly in terms of traffic congestion. Traffic data company Inrix ranks Ireland 52nd out of 220 congested cities in 2018 – LA is the worst. Another company , Tom Tom, estimates that Dublin is the 14th most congested city internationally, with peak-time commuters forced on average to spend an extra 26 minutes undertaking a journey which would take 30 minutes in free-flowing traffic.
3. Congestion – What’s happening?
More than seven out of every 10 journeys are made by car in Ireland. Traffic volumes soared as the economic boom took hold, with annual passenger vehicle kilometres rising 29 per cent to 58.9 billion between 2000 and 2008.
Road travel fell by 4.6 per cent between 2008 and 2012 – this led to a fall in traffic on some of our major tolled roads and a standstill on others. However traffic has picked up with the recovery, with indicators showing a sharp rise across the network and key roads, such as the M50 in Dublin – where flows can exceed 150,000 per day on the busier parts – and the N40 South Ring Road in Cork – more than 85,000 vehicles daily in busier parts – hitting capacity problems regularly.
There is also heavy growth on the Dublin radial routes, the major roads leading on to the M50, including the M4,N7, M1 and M11, with volumes rising strongly last year and more than 100,000 vehicles per day regularly recorded on some stretches.
The M50 is the State’s busiest road, with 1.52 billion vehicle kilometres driven on it last year. This was an increase of just 1 per cent on the previous year – indicating that the road is touching capacity, with nearly 145,000 vehicles using several sections on an average day. Parts of the M50 are at what, in the jargon, is called “breakdown flow” – they are chronically congested.
The graphics for the two M50 stretches – and one in Roscommon to show a road outside a major city – all compare 2014 and 2019. The M50 data, including on the busiest stretch between junctions seven and nine, shows that while the actual daily peaks have not risen by too much, the commuting period has stretched significantly, with more people leaving from 6am on to avoid the worst of the traffic. More are also leaving work earlier, or later, in the evening.
People are adjusting their lives to the reality of the traffic, at a cost
An examination of the data for November and early December this year and five years ago , for example, shows an 86 per cent rise in the number of journeys between 6 and 7am on workdays. In contrast, the rise in the following couple of hours over five years is considerably more modest.
This is a key insight into the impact of congestion on people’s lives – and how this has worsened over the past five years. People are adjusting their lives to the reality of the traffic, at a cost. And it is now a factor in where people decide to take up employment.
The data for the N40 in Cork near the Jack Lynch Tunnel, taken from a TII study, tells the same story in another way. It shows how average speeds crash at rush hours – and how the length of time the peaks, and thus slows speeds, last has also extended. Even on the Roscommon road, the peak hours have spread and traffic volumes have risen significantly.
The second point to note is the much higher spread of traffic in the non-commute periods in the middle of the day, presumably tied at least in part to rising population, more freight movements and more other “business” traffic, from the ubiquitous white vans to people going to and from appointments. It is an arguable point now where peak time starts and ends as the graphs flatten out during the day-time and evening period. Total November traffic on the M50 section referred to above has risen 14.5 per cent over the last five years, to a daily average of over 160,000.
4. Congestion – the policy issues
For years one of the key answers to congestion was clear – build more roads. The State went on a major building spree for motorways between Dublin and the other major cities – and to an extent between other cities. Many of these roads now operate below full capacity for much of the day – indeed on average secondary roads, which have seen less investment, operate closer to capacity. Now, however, national goals have changed. There will be continued investment in roads, but the goal is to move people out of cars, where possible, get more to live beside public transport networks closer to cities and improve train, bus, tram and cycling and walking routes. The latest housing data, however, as highlighted in a report from the Banking and Payments Federation Ireland, shows that many people are being pushed out to the commuter counties by high Dublin house prices, which guarantees more traffic on the roads into Dublin in the years ahead.
Almost four out of every 10 car trips in Ireland are for less than 15 minutes
The National Transport Authority transport strategy reflects these goals, saying that the goal of policy is to have people living in a more “compact” way, with fewer car journeys. The M50 is one focus – and one example of the intended policy direction – with traffic growth seen as “unsustainable”. The goal, in particular , is to cut the number of short-trips on the M50 – people popping on and off. This is part of a wider national strategy to get people out of cars and into buses or trains or on bikes for short commutes or trips to school, the latter seen as a vital congestion factor. Almost four out of every 10 car trips in Ireland are for less than 15 minutes.
For the M50, the goal is to try to return it to acting as a carrier for longer-distance and commercial traffic. However there is also a realisation that car travel remains vital for many who live well outside Dublin city centre and in the commuter counties – many not having viable public transport options to get to Dublin to work.
This story is repeated around the State. There will be an emphasis on public transport and over time encouraging people to live closer to where they work. But with a widely spread population, the Dublin commuter countries growing strongly and many having limited options, the strategy also involves ongoing investment and improvement in roads. And new strategies in traffic management, with evidence in some major cities internationally that these can also bear fruit. Getting the balance right will be key. But unless the economy slows sharply, the toll taken by traffic congestion looks set to worsen over the next few years.
