There has been a lot of media coverage concerning cross-border traffic flows over the past year or so, mostly focused on cross-border shopping (IAN post here). We have been trying to source some data that would reveal the numbers of cars crossing the border on a daily basis. In our naivety, we thought it might be a relatively straightforward task given the number of traffic cameras and traffic management induction loops on the principal roads, but such data has proven quite tricky to come by. Recently though we have received some data generated by the Department of Regional Development in the North. They monitor traffic flows at 12 traffic census points along the full length of the border. The data is a little out of date at this stage and relates to 2007 flows, and it is a little limited in nature, but it does give us some picture of cross-border movements.

The first map shows average cross-border daily flows for Monday to Friday, although it does not breakdown the hour or direction of the flow (although a sizable proportion of the vehicles are moving across the border and then back later in the day). The roads with the greatest flow of traffic run between Donegal and Derry (A2, Letterkenny/Derry (18,290) and A38, Lifford/Strabane (19,290)). Next, and a little way behind, comes the M1, Newry/Dundalk route (14,140). In total, on an average work day in 2007, 97,190 vehicles crossed the border. Assuming that the vast majority of journeys are bi-direction and have 1 to 2 people in the car, the data would indicate about 1-2 percent of the population of the North and South (c.50,000-100,000 people), cross the border daily.

Average daily cross-border traffic flows, 2007

The second map details the hour of peak AM flow in each direction. Interestingly, the peak hour of traffic flow on the three routes with the highest traffic is 11am in both directions with the exception of the M1 southbound which is 8am. This suggests that a large proportion of the cross-border journeys, in both directions, are not related to either work or schooling (although such flows undoubtedly occur, but as a smaller proportion of all trips). Along the south-west part of the border, between Leitrim/Sligo and Fermanagh, however, it appears that there is relatively substantial work related morning trips in both directions, but especially from the South to the North.

Peak hour of cross-border traffic flow in each direction, 2007

Clearly we’re only provided a limited snapshot here of cross-border traffic flows, but it’s a start. Hopefully we can source some more timely data that has hourly breakdowns that detail how many vehicles are travelling in each direction.

Justin Gleeson and Rob Kitchin