M6 Junction 32

2009 has seen an improvement to this junction, details which are given at the foot of this page. For over 40 years this junction was the reason for long southbound queues, what follows gives the reasons for this:-

You are traveling home after a summer's trip to the Lake District, it is late Sunday afternoon, the traffic from Windermere has been heavy but moving, you have just past Forton Service's, round a corner and suddenly the traffic comes to a halt. If that has been your experience, particularly more than once then you will like have a good idea that the queue will end at junction 32 at Preston about 8 miles south. What causes these queue's which happen all too often through the spring, summer and early autumn, particularly on Bank Holiday weekends? On this page we look at junction 32 and the effect it has on the motorway system.

As can be seen from the map below junction 32 is once of the most complex interchanges on this part of the M6, serving both the M55 and A6. However it started out in 1958 as a much simpler junction. This was the northern end of the original Preston bypass, the roundabout and slip roads the lead from the roundabout to towards the M6 are still the same as in 1958 despite so much alteration else where. From 1958 to 1965 this junction was like is shown below:-

There are several features of this we do not see on more modern motorways, notice the two lane M6 and the wide central reservation. The sharp bend where the main junction is now, it was described on signs at the time as , 'Temporary Bend.' The junction was built for there in stages to reach what we see above. In 1965 the M6 north was added. The junction as it was between 1965 and 1975 is shown below, note in both early examples of how the wide central reservation coming up to the roundabout made provision for the M55 to Blackpool 17 years before this was built. Whilst in 1975 the M55 was opened, the final chance came in 1995 with the adding of a forth lane to the M6 south of this junction up to the M61 .

Why the queue's on the southbound carriageway? One of the longest queue's every reported on a British motorway was an this section stretching from this junction at Preston, back about 25 miles to Carnforth (source : Guinness Book of Records).

The simple answer is that this junction was designed in the late 1950's, although the planners tried to look forward the never foresaw the heavy traffic that this motorway would carry. The idea that one lane would be used for traffic leaving the motorway and 2 lanes would continue on for about half a mile and then be joined by a third lane merging from the left bringing traffic onto the motorway may have seemed a good idea at the time and may well have been seen as safer than conventional junctions particularly at the point where the two roads merge. However it leaves out the fact before the junction that slow traffic in lane 1 need to move over to join lane 2 slowing down this lane and forcing slower traffic on lane 2 into lane 3. This works fairly well when the motorway is quiet but when busy it can cause major tailbacks. Take a look at the simulation below:-

I wondered how this would work out in simulation, however it worked out the same as happens at junction 32, watch the back of the queue as the motorway gets busier, notice the stop start action created as vehicles try to push into these lane from the left. When busy, you may have to watch it a few times, but when busy every time a vehicle moves to the lane on the right it does two things, firstly because it needs to be sure of a gap in the next lane it slows down, slowing down the lane it has left, as traffic in the lane it is going into needs to create a gap then that lane has to slow, however as traffic does not always move right at the same point it produces a stop start effect particularly in lanes 2 and 3, as the motorway gets busier then the end of the queue moves back along the motorway producing this stop start effect you see in a lot of slow moving motorway queues. This is not just related to this junction but to motorway queue's caused by roadwork's, heavy traffic etc apart from something like a major accident which totally blocks the motorway.

Coming northbound is slightly better at this junction than southbound and much better since the inclusion of 4 lanes however it is not without problems, look at the simulation below:-

This shows a day when traffic is moderate, but most traffic is going north rather than to Blackpool. However some cars still need to move from lane 4 to lane 2 whilst a number of lorries need to move from lane 1 to lane 3 causing a criss cross motion. See how many near misses you spot, there have been a number of accidents here likely this criss cross would be a factor, particularly if a driver fails to note the overhead signs and does not change lanes until the junction is upon him.

2009 Improvements