A6 Toome Bypass must be grade separated

I was delighted to see the announcement last week that construction of the proposed expressway from the M22 at Randalstown to the A31 Magherafelt bypass (the “Castledawson Roundabout) will proceed this year.

This particular stretch is one I have long campaigned for, because:

  • it is the narrowest and most dangerous stretch of the Belfast-Derry road (particularly the “Moneynick” section east of Toome);
  • the road actually serves not just the North West but also Mid Ulster, so it assists a significant section of the population; and
  • construction will relieve a very particular daily congestion black spot (again, at Moneynick).

However, there is a problem. The new road will be expressway all the way (i.e. left entry/exit only with entirely “grade-separated junctions”, i.e. bridges/flyovers on roads crossing it) except at Toome. Although the initial proposals for the new expressway involved removal of the roundabouts on the Toome Bypass (which should never have been constructed on the main line of the road in the first place), this was subsequently revised to leave two in place. This is an astonishing lack of foresight, because traffic which is almost universally passing Toome will have to compete, twice, with traffic going in and out of the village and to minor adjoining roads. It does not take a genius to work out that this will inevitably create a significant bottleneck, as it will restrict the ability of the mainline to flow. Thus, the congestion on the current road will be relieved, but not eliminated (as it would be if the roundabouts were removed).

The roundabout at the eastern end of the Toome Bypass will be enlarged - but we may be sure that, within months, road users will be demanding its outright removal. They'll be right...

The roundabout at the eastern end of the Toome Bypass will be enlarged – but we may be sure that, within months, road users will be demanding its total removal. They’ll be right…

Therefore, constructing the road as currently planned will inevitably lead to calls to remove the roundabouts (relatively easily doable simply by constructing an overhead bridge at the two roundabouts and connecting west-facing slip roads at one and east-facing at the other). It will in fact be more expensive to leave it to later – to construct the new expressway (actually new expressways, as there will in effect be one either side of the existing Toome Bypass) and subsequently return on a different contract to sort out the roundabouts will cost much more in terms of time and money than it would have done just to construct the lot (including roundabout removal) at once.

The fundamental error “Transport NI” is making here is placing the focus solely on capacity, rather than flow. It has already made such a mistake, in carrying out the A12 Westlink underpasses without at the same time sorting out the York Street lights. The basics even of traffic light phasing require consideration of flow as well as capacity (indeed a roundabout on the A2 Bangor “Ring” Road has recently been converted to add lights precisely to aid the flow). This basic principle is hardly new – the M1 in Co Armagh still does the job half a century on precisely because such foresight was displayed then. Why not now?!

None of this should delay construction of the new A6 expressway because it will still have safety and capacity advantages. But, as work gets under way, it would be prudent to reconsider and change the decision not to remove the Toome roundabouts. They will be removed eventually – why not just remove them now, and maximise the benefit for the millions of our money being allocated to this otherwise worthy project?

The fact is this is a second rate road – albeit replacing a fifth rate road. We seem to accept this too easily in Northern Ireland – with nearly all public services, well beyond roads. But really, we should by now be expecting first rate. It is time to raise our ambitions and expectations!

 

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8 thoughts on “A6 Toome Bypass must be grade separated

  1. John says:

    The roundabouts need to be made grade separated. Look at what they did in the North West when the A2 was upgraded to dual carriageway from the City of Derry Airport into the city. Although it is now much safer, journey times are no better due to having to stop at each of the 6 roundabouts on the short five and a half mile section which can get congested at peak times. By the time you build up any speed you have to start braking for the next roundabout. Why wasn’t this upgrade done properly by making these roundabouts into grade separate junctions?

    • I’m glad you mentioned your experiences on that road. Obviously, I’ve only experienced it off-peak.

      I don’t know the ins and outs of the planning process there, and there is a better case for roundabouts when significant traffic is entering or leaving the road (as would be typical in and near urban areas). However, your experience indicates that again, that stretch is an improvement but it is well short of optimum. That really is regrettable.

    • I can understand the terminating roundabout at the Airport (at least until dualling is extended further towards Limavady). However the Campsey and Broadbridge junctions should have been grade separated from the start. Broadbridge even has a footbridge next to the roundabout. It cannot be astronomically more expensive to replace this with a road bridge and convert the side roads on both sides to leftin-leftout junctions

      • Really interesting.

        Like I say, I hadn’t had much time to think about it, having only ever driven the road mid-morning or evening.

        The problem is, once it is built, the tendency is not to return to it because the safety advantages are limited.

        It is very frustrating, but I’m glad the example was raised to enhance the debate.

  2. […] under construction and as of later this year the third (A6 Randalstown-Castledawson discussed last week) will be too. It would be no surprise the see the announcement of the first section of the fourth, […]

  3. […] it is already risky to be carrying out the (already flawed) A6 Randalstown-Castledawson upgrade (given it is on the same broad northwestern corridor that ends […]

  4. […] the understandable excitement about grand projects like the A12 York Street interchange or the A6 Moneynick upgrade, funding is being cut back from basic maintenance. Many readers in Northern Ireland will […]

  5. […] is the new 14km expressway to be built in Co Londonderry on the Belfast-Derry road. I have a significant problem with the plans for the road, but I nevertheless recognise that, on balance, it is a good thing. With the Republic […]

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