Operation Brock

Published on 27 March 2019

It costs £30m, it's been in planning since last May and it started on Monday this week. Operation Brock has arrived on the M20 in Kent, and it looks like it'll be here for a while.

Back in May last year, we reported on Government plans to improve Operation Stack, the system used since 1988 to turn the M20 into a lorry park when Channel crossings to France are disrupted. The idea was to set up a contraflow between junctions 8 and 9 so that traffic could stay on the motorway while the stack was in operation. At the time, the Government said only that it was for use during "Channel disruption", and that it would be ready by early 2019. We thought it safe to hazard a guess that it might have something to do with Brexit.

Since then, if you live in Kent, you'll have been seeing and hearing quite a lot about Operation Brock - rumoured to be a contraction of "BRexit Operations aCross Kent". That is the new name for the measures announced last year.

The M20 at Harrietsham on Tuesday 26 March, with the Operation Brock contraflow in operation. Click to enlarge
The M20 at Harrietsham on Tuesday 26 March, with the Operation Brock contraflow in operation. Click to enlarge

Last week, Highways England announced weekend closures of the M20 that would enable them to activate Operation Brock from Monday 25 March. The trigger is indeed Brexit, and more specifically the fact that the UK is on the brink of leaving the EU but still does not have a withdrawal agreement, and nobody knows exactly what might happen to cross-channel freight. We might, any day now, suddenly need somewhere to put an awful lot of lorries.

What's happening?

A contraflow has been installed on the M20 between junctions 8 (east of Maidstone) and 9 (Ashford). The Londonbound carriageway has been partitioned with a continuous metal crash barrier, of the type often used in roadworks, allowing two lanes of traffic each way. A 50mph limit has been applied throughout, monitored by average speed cameras. A free recovery service is in operation to remove stranded vehicles in the absence of a hard shoulder or emergency lay-bys, and the parallel A20 - expected to be busier than usual - now has a temporary "no stopping" restriction.

Temporary clearway signs on the A20. Click to enlarge
Temporary clearway signs on the A20. Click to enlarge

That frees up just over 13 miles of coastbound carriageway for use as a lorry park. The set-up is slightly more elaborate than for Operation Stack: cones have been set out to enforce the two lines of lorries, with a single line of trucks headed for the Channel Tunnel on the hard shoulder, and another single line in lane 3 for Dover. The remaining two lanes are used for access by emergency services and welfare facilities.

Coastbound traffic approaching junction 8 at Maidstone is now directed into lanes 2 and 3; lane 1 is now signposted for the exit and for cross-channel lorries only. The contraflow then begins just west of the junction. Lorries joining the stack pass under the junction and join one of the two queues. Because the queues begin underneath the junction, the coastbound entry sliproad from junction 8 is now closed: traffic wishing to join the M20 now follows a diversion route west along the motorway to junction 7 before doubling back, a major inconvenience if you only wanted to make a quick stop at Maidstone services.

Once lorries are in the stack they are subject to a 30mph limit - for the whole tedious 13 miles, though it will matter less once it's full - and the exit back to the motorway at Ashford is controlled by Kent police, who will release lorries as crossings become available.

Does it work?

On a weekday lunchtime, yes. The M20 between Maidstone and Ashford is not especially busy compared to most interurban motorways, and two lanes are enough to meet demand without delays. In the rush hour things may get a little less comfortable.

In terms of road safety, though, the results so far are mixed. Local press are, two days in, calling the scheme a "disaster" thanks to the number of accidents that have taken place so far. Reports like that are often a little sensational, and any new system of traffic management may need a few days to bed in, but it was noticeable that in the hour I was there to take some pictures on Tuesday afternoon, there was a major accident eastbound at the start of the contraflow and a lane closure at Ashford because of another.

Freight bound for Dover in the Operation Brock queue. On the right, the contraflow doesn't seem to disrupt weekday traffic. Click to enlarge
Freight bound for Dover in the Operation Brock queue. On the right, the contraflow doesn't seem to disrupt weekday traffic. Click to enlarge

Is it going to be enough?

It depends how many lorries there are. The current set-up effectively provides only phase 2 of Operation Stack, which we estimate allows space for 1,500 trucks. At its height, in 2015, Operation Stack involved the closure of more than 40 miles of carriageway and accommodated three times that figure.

In fact, we are only presently seeing the first stage of Operation Brock. If lorries start to build up and space on the M20 runs out, Manston Airfield in North Kent will be opened for use as a lorry park. Vehicles bound for Dover will be sent there, while the M20 will be used exclusively for the Channel Tunnel. If that doesn't release enough space, the third stage would be to close the entire M26 to traffic and use that as additional space for Channel Tunnel vehicles.

In addition to the work already carried out on the M20, new technology has been installed on the A256 between Manston and Dover, similar to that already in place on the A20 approaching Dover from Folkestone, that allows the management of long queues of lorries en route to the port.

How long will it stay?

Nobody knows. Three things are clear, though, and hint at how long Brock might be with us in its present form.

It's funded until late September. Back in May 2018, £30m was allocated to Highways England to set up Operation Brock, and that money was said to be for the initial works (presumably including procurement of a lot of contraflow barrier and new signs) and would also cover running costs for the first six months it was in use. If that still applies, there's money in the pot to maintain this situation until the autumn. After that, more money could be found for it if needed, of course.

It's here until at least mid April. The press release announcing that Brock would begin on Monday 25 March also says that "three lanes in each direction could be restored, with a 50mph limit, if Operation Brock is assessed as unlikely to be required in the following weeks." That strongly suggests that, to hedge their bets, Highways England will keep everything in place until they're certain it's not required, and that will be mid April at the earliest. The present political situation suggests that mid April may be optimistic.

The installation is semi-permanent. In the past, the problem with creating a contraflow so that the M20 could remain in use while Operation Stack was running was that the traffic management cost several hundred thousand pounds and required several days to set out. It couldn't be installed fast enough when Stack was required. Operation Brock is, essentially, the result of a decision to just permanently install a contraflow and removes the expectation that the M20 will actually re-open in full any time soon. Just take a look at the installation job.

The refurbished London-bound carriageway, with new road markings, rebuilt verges, markerposts and a semi-permanent barrier. Click to enlarge
The refurbished London-bound carriageway, with new road markings, rebuilt verges, markerposts and a semi-permanent barrier. Click to enlarge

The contraflow is not just traffic management. The new central barrier has been bolted in to the road surface, so removing it is not going to be a trivial job. Unlike a standard roadworks set-up, the whole 13 mile length of the Londonbound carriageway has had its road markings burned off and replaced, so the available carriageway space has two lanes of equal width in each direction rather than one lane of traffic travelling in a narrow hard shoulder. Edge lines have been painted hard up against the edge of the carriageway, where normally there would be a narrow strip between the edge line and the verge, to maximise the available space.

Beyond even that, in many places the verges appear to have been dug out and reconstructed with gravel, to level off the transition between the carriageway and the ground, because vehicles will now be running much closer to the edge. And new markerposts have been installed at frequent intervals, complete with red reflectors against the central reservation facing coastbound traffic.

Again, nobody knows how long Operation Brock will stay. It is here for at least a few weeks and in all likelihood longer. But one conclusion we can draw immediately is that the people who designed and installed the contraflow were not expecting it to be removed any time soon.

We will, of course, keep an eye on it, as we have done for the last year. Watch this space.


James Armitage 27 March 2019

For the past five years I've been driving down the full length of the M20 once a fortnight so I know the road well and I've seen the scheme being slowly introduced.

It really doesn't surprise me to hear that there have been several accidents in this section in the first couple of days of operation. There will be many more, for sure. Even before these 'roadworks' were introduced and the road was a standard three lane motorway, I've regularly seen lorry drivers swerve out of their lane onto the hard shoulder and/or into lane two for no other reason than apparent tiredness. It's important to remember that most of these drivers - in both directions - will have travelled many miles to get to Kent. The monotony of the thirteen miles with no junctions or other road features in between has always been a concern, but now with the 50mph hour limit from the new junction 10A works at Ashford to the smart motorway works the other side of Maidstone, the M20 is like a hypnotist's watch at the moment. Add to that the narrow lanes with zero room for error, and no emergency refuge areas, and it's truly a recipe for 'disaster'.

Anonymous 29 March 2019

It does sound like an interesting idea. It will need some changes for permanent use.

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Published27 March 2019

Last updated4 February 2020