Chapter 5 - Road traffic

Introduction

This chapter provides information about road traffic, such as the total volume of traffic by type of road, by type of vehicle, and by council area. It also provides figures on traffic flows at selected points on the road network, selected statistics on delays and congestion and information about petrol and diesel consumption.

Traffic estimates, indicate only the broad level of traffic, so year - on - year comparisons should be made with care as they are based on a very small cross-section of the roads in Scotland: 12 hours in one day traffic counts taken at around 750 sites per year and data from automatic traffic counters at about two dozen sites in Scotland (then combined with data from automatic counters at similar sites in England and Wales). See Sources section.

Key Points

• 47 billion vehicle km were driven in 2022, a 9% rise compared with 2021.
• 40% of the distance travelled on the road network is on Trunk roads, which account for only 7% of the road network.
• 11% of driver journeys were delayed by congestion in 2022.

Main Points

Major and Minor Roads

The estimated volume of traffic on Scotland's roads in 2022 was around 47 billion (thousand million) vehicle km: 9% more than 2021. As with other types of transport, road traffic was significantly affected by the Coronavirus pandemic. However, since restrictions have lifted there has been a recovery in the amount of road traffic. There had been slight increases in the previous eight years, following the steady downward trend seen between 2007 and 2011. (Table 5.1)

The total volume of traffic on major roads (Motorways and A roads) in 2022 was estimated to be 30.4 billion vehicle-km. Traffic on Motorways accounted for 8.3 billion vehicle km (18% of all traffic). This was less than the estimated 10.6 billion vehicle km on trunk A roads (22% of the total), and the 11.5 billion on non-trunk A roads (24%). Sixty eight per cent of A road traffic was in rural areas: 14.9 billion out of the A roads total of 22 billion vehicle km. (Table 5.1)

Minor roads (B, C and unclassified roads) accounted for the remaining 36% of traffic in 2022: an estimated 17.0 billion vehicle km (Table 5.1)

The total volume of traffic on major roads (Motorways and A roads) in 2022 was 10% higher than in the previous year (Motorway traffic increased by 12%). Minor road traffic was about 7% higher than in 2021. Traffic levels are around 9 per cent higher than in 2012. (Table 5.1)

Trends

Prior to 2020, traffic volumes on major roads in Scotland had been broadly increasing over the past three decades. The volumes reached a peak in 2007 and fell back slightly before rising to new highs in 2019. In 2019, traffic volumes on major roads were 46% higher than in 1995. Motorway traffic saw a 14 per cent rise between 2003 and 2008, fell slightly over the next two years before resuming its rise in the years leading up the pandemic. However, due to the Coronavirus pandemic restrictions lifting in 2021 motorway traffic is now 24% higher than the earlier peak in 2008. (Table 5.1)

Traffic on minor roads is estimated to have risen by 4% between 2003 and 2007, falling by 2% between then and 2012, before rising again. The total volume of traffic on all roads in Scotland was also estimated to have risen by 5% between 2003 and 2007, falling by 2% between then and 2011, before rising again in the years before the pandemic. (Table 5.1)

Cars account for over three quarters (73%) of the total volume of traffic on the roads (i.e. of the total for major roads and minor roads combined), light goods vehicles for 20% and heavy goods vehicles for 5%. Pedal cycle traffic fell by 3% in 2022. However, pedal cycles still account for only one percent of estimated traffic volume. (Table 5.2 & 5.3)

In 2022, the volume of car traffic was 2 per cent higher than in 2012, light goods vehicle traffic 49 per cent higher and bus vehicle traffic 22% lower. (Table 5.3)

Local Area volumes

The seven local authorities with the highest traffic volumes (Glasgow, North Lanarkshire, Aberdeenshire, Edinburgh, Fife, Highland and South Lanarkshire) account for 46% of all traffic on Scotland’s roads. (Table 5.4)

Selected trunk road traffic flows are given in Table 5.7. The A720 Dreghorn was the busiest site from this sample, with an annual average of 79,604 vehicles per day in 2022. Its Monday-Friday average was 84,177 vehicles per day. The A720 Dreghorn had the highest Monday-Friday peak hourly flows at 5,981vehicles in the morning and 6,046 vehicles in the evening. At the opposite end of the scale, the A835 Aultguish averaged 1,770 vehicles per day over the year as a whole and its Monday-Friday peak hourly flows were 127 in the morning and 169 in the afternoon. The M74 J18 to J19 had the highest percentage of heavy goods vehicle traffic in 2022 at 33% for the week, followed by the A80 Cumbernauld (26%). (Table 5.7)

Delays and Congestion

In previous editions of STS Table 5.8 estimated the time lost by traffic due to delays on trunk road routes monitored by Transport Scotland. This table is no longer being updated due to number of factors, including major changes to the network which would have required a substantial rework to the methodology.

The Scottish Household Survey provides estimates of delays attributed to congestion experienced by drivers (on the previous day). In 2022, 11% of journeys made as the driver of a car were said to be delayed due to traffic congestion. Short delays were more common than longer ones - 4% of car drivers’ journeys were delayed by around 5 minutes compared to 2% by 15 minutes or longer. Weekday journeys were most likely to suffer congestion delays between 7 and 9 am and 4 and 6 pm (15-19% and 19-21% respectively). Fewer delays (3%) were experienced by people residing in remote small towns than those in accessible small towns (8%). (Tables 5.8 and 5.9)

These statistics no longer feature in Scotland’s National Indicator on driver congestion in their old form. More information on National Indicators can be found on the Scotland Performs website.

Delays experienced by bus users have fallen since 2008, though changes in recent years are not significant due to small sample sizes. (Table 5.9)

Fuel Consumption

DECC estimates suggest that the traffic on Scotland's roads consumed 3.1 million tonnes of petrol and diesel in 2021. This figure includes fuel purchased outwith Scotland which is consumed in Scotland, and excludes fuel purchased in Scotland which is used outwith Scotland. It is estimated using information about average fuel consumption, vehicle emissions and traffic volumes - see road traffic section of the user guide.

Petrol and diesel consumption has been rising since 2013. However, the figures for 2020 and 2021 will have been affected by the Covid pandemic. There has been a steady fall in petrol consumption in cars over the period and an increase in diesel cars, reflecting trends in vehicle propulsion shown in Chapter 1 i.e. increases in the proportion of diesel powered vehicles on the roads and reductions in petrol powered vehicles. (Table 5.10)

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Notes

Note 1

Estimates for minor roads for the period since 2000 have been revised to take into account the minor road benchmarking exercise. Further details

Note 2

Estimates for 2020 will have been affected by the Covid 19 pandemic.

Note 3

DfT's classification of urban and rural roads differs from the built up/non-built up classification - see section 5.1.4 of the traffic estimates notes and definitions at the back of this publication.

Note 4

Motorways include A(M) roads.

Note 5

Roads which changed from trunk to local authority, or vice versa, are counted according to their status on a recent date,

Note 6

DfT have made some minor changes to the traffic estimates from 2006 onwards. This was due to incorrect LA codes

Note 7

Traffic flows are counted in both directions at ATC sites and the average flows are based on totals.

Note 8

Missing data for these sites is due to equipment failure. Year averages may be based only on data for part of the year, in cases where equipment was not working in some months.

Note 9

7 day flows were calculated from Monday to Sunday inclusive, '5 day flows' were calculated from Monday to Friday inclusive

Note 10

Flows were calculated from Monday to Sunday inclusive.

Note 11

This information is obtained from the Scottish Household Survey Travel Diary questions about the (stages of) journeys which the respondent had said that he or she made as the driver of a car or van.The table does not include those (stages of) journeys for which the questions about traffic congestion were not asked.

Note 12

Car drivers were asked "was this part of your trip delayed due to traffic congestion?". No definition of "traffic congestion" is given, so respondents can interpret the term as they wish.

Note 13

Those drivers who said that they had been delayed by traffic congestion were asked "how much time do you think was lost due to traffic congestion?".

Note 14

Previously split into 'about 20 mins' and '25 to 30 mins' but now combined to be '20 to 30 mins'. If previous split needed please request via Transtat@transport.gov.scot

Note 15

Due to changes in the survey in response to covid-19, 2020 data is not directly comparable with previous years, so there is a break in the time series between 2019 and 2020 and 2021 and 2022

Note 16

These estimates are of the total amount of petrol and diesel consumed by vehicles travelling in each Council area (i.e. the estimates are based on where the vehicles were driven, rather than - say - the area of the registered keepers of the vehicles).

Note 17

There have been major revisions to the data due to improvements in the methodology. For more information please see here: https://www.gov.uk/government/collections/road-transport-consumption-at-regional-and-local-level#methodology

Note 18

The traffic counter data for the A90 Bridge of Don is no longer being collected.