Published: 08:58, 28 October 2019
| Updated: 14:16, 28 October 2019
The no-deal traffic plan means a contraflow system is now in place between junction 8 (Maidstone) and 9 (Ashford).
Highways England workers spent the weekend and this morning laying out 7,500 cones and 350 signs before the scheme could be activated.
Here's what it means for motorists:
Drivers of lorries weighing more than 7.5 tonnes heading for Eurotunnel or the Port of Dover on the M20 should follow signs directing them onto the coastbound carriageway between junctions 8 and 9 for Ashford.
A 30mph speed limit is in place and, in the event of disruption at the ports, lorries could be queued on this section of motorway.
All other drivers can continue their journeys as normal. On the M20, two lanes remain open to traffic in each direction between junctions 8 and 9, using a contraflow on the London-bound carriageway, with a 50mph speed limit in place.
Operation Brock is the name for a series of measures which can be deployed to mitigate congestion on the county's roads in the event of lengthy delays to cross-Channel traffic.
It has stages that can be deployed sequentially, scaling up or down to meet demand.
In addition to the M20 contraflow, lorries can be routed to Manston Airfield and, if needed, the M26 motorway can be closed and used to queue HGVs too.
The operation is an interim measure which was deployed in March and keeps the M20 open in both directions.
A Highways England spokesman said: "It has been deployed now in response to potential delays at the ports in the coming days or weeks. Its deployment will be kept under continual review and it will be stood down when it is no longer needed."
For more information on how Operation Brock will affect your journey click here.
KMTV report on Operation Brock
More by this authorEd McConnell
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