Impacts of COVID-19 Restrictions on National Road Traffic

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Transport Infrastructure Ireland (TII) operates a comprehensive network of over 350 traffic counters and sensors across the national road network incorporating dedicated traffic monitoring units as well as barriers and camera based sensors at PPP toll plazas, M50 eflow and the Dublin tunnel. This network of traffic counts provides a comprehensive overview of traffic movements across all parts of the national road network.

In response to the COVID-19 pandemic, the Government of Ireland imposed restrictions on the movement of people in order to contain the spread of the virus. This commenced with the closure of all schools and colleges from March 13th 2020. Further restrictions involving the retention of essential services only were announced on March 24th 2020. On the evening of Friday March 27th 2020, a Government announcement was made which advised all citizens to stay at home and to only leave their homes for a limited number of reasons.

Reduction in national road traffic volumes in context

The restrictions implemented by Government in order to tackle the spread of the COVID-19 virus have had significant impact on national road traffic volumes. The scale of the reduction where traffic volumes since the restrictions imposed on March 27th 2020 have reduced by 65-70%.

Aggregated traffic volumes on national roads since March 30th 2020

The variation in daily traffic volumes since March 30th compared with an average of typical working day volumes between March 30th and April 17th, i.e. for the first three weeks of restrictions excluding weekends and public holidays shows that volumes have been generally stable over the recent weeks with some increases in movements noted this week beginning April 20th.

TII was requested by DTTaS to report on road usage for the day of Monday 20th April. On that day traffic volumes were broadly representative of typical weekday conditions over the period of the COVID-19 restrictions, being within 5% of recent average weekday volumes.

However since Tuesday April 21st traffic volumes on national roads started to increase above recent average volumes. Other sources being used by Government agencies, including seismic data and mobile phone data, have shown similar trends. These sources would pick up a much greater level of short distance / local movements where recent increases may be more noticeable. The majority of the TII data covers the strategic road network and will reflect patterns of more non-local movements. It should also be noted that checkpoints set up by An Garda Síochána on national routes would probably be acting as a deterrent to travel on these routes, possibly to a larger degree than on local road networks.

Comparison to Typical Traffic Levels; General Traffic

A summary of the impacts of the restrictions on general traffic, i.e. all classes of vehicles, represents an analysis at selected locations whereby traffic volumes in April 2020 are compared with the equivalent weekday in 2019 and the aggregate percentage change.

The emerging impacts of the restrictions on vehicular travel can be summarised as follows:

  • Prior to the March 27th restrictions, the reduction in general traffic volumes was of the order of 40% on weekdays.
  • In the week following the announcement of restrictions on Friday March 27th, there was a reduction in traffic volumes across the network of the order of 65-70%.
  • The reduced traffic volumes have continued into this week beginning April 20th, however there were some increases in traffic this week compared with recent weeks as noted above. Overall traffic is down 60-70% when compared with the equivalent weekday traffic flows in 2019.
  • This reduction is broadly consistent across all parts of the country including the motorway corridors and the M50.
  • Again, traffic reductions at the weekends are even greater with reductions of up to 80% observed on Sunday April 19th.

 

A breakdown of the impacts for heavy goods vehicles (HGV), light goods vehicles (LGV) and private cars is detailed as follows, along with a summary of impacts in the Dublin Tunnel.

Heavy Goods Vehicles (HGVs)

Since March 27th there was a clear reduction in HGV traffic volumes of the order of 30-40% which has continued into this week. It should be noted that the 2019 equivalent period to Friday 17th – Monday 20th April 2020, i.e. Friday 19th – Monday 22nd April 2019, was the Easter Bank Holiday weekend in 2019. Year on year daily comparisons on these dates are impacted by seasonal patterns. This has a significant impact on the comparison of HGV volumes particularly on Easter Monday 2019, where volumes were very low.

Light Goods Vehicles (LGVs)

Since March 27th volumes of LGVs have reduced by over 50%. These reductions in LGV traffic have continued this week beginning April 13th. It should be noted that the 2019 equivalent period to Friday 17th – Monday 20th April 2020, i.e. Friday 19th – Monday 22nd April 2019, was the Easter Bank Holiday weekend in 2019. Year on year daily comparisons on these dates are impacted by seasonal patterns. This has a significant impact on the comparison of LGV volumes particularly on Easter Monday 2019, where volumes were very low.

Private Cars

As private cars represent approximately 80 to 90% of all traffic, the reduction in private car traffic is very similar to trends for general traffic discussed above, i.e. namely a reduction in the order of 65-75% compared to 2019 figures.

Dublin Tunnel

The emerging impacts of the restrictions on vehicular travel can be summarised as follows:

  • In the Dublin Tunnel since March 27th TII is seeing reductions in general traffic exceeding 60% on weekdays.
  • The reduction in HGV volumes in the tunnel has been in the region of 30-40% on weekdays following the restrictions imposed on Friday March 27th. In the period between Monday March 30th and Thursday April 24th, weekday HGV volumes through the tunnel have averaged at approximately 6,600 vehicles per day.
  • The additional restrictions have resulted in a dramatic fall in the use of the tunnel by private cars. During week commencing March 23rd, car volumes through the tunnel were approximately 5,000 – 6,000 per day as compared with normal weekday volumes of over 16,000. In the period between Monday March 30th and Thursday April 24th, car volumes have reduced to an average of approximately 2,400 per day, an overall reduction versus normal conditions of almost 85%. There is now much less incentive for cars to use the tunnel as other routes into the city that are normally heavily congested are now experiencing free-flow conditions.