Operation Stack, also known as 'Op Stack' is a way of managing traffic during disruption to Eurotunnel or ferry services in Kent. Lorries waiting to use these services queue on the M20 and all other traffic is diverted to other routes.
Op Stack is used between Junction 8 (Maidstone services) and Junction 9 (Ashford) on the M20. If more space is needed, the closed section will extend to Junction 11 (Westenhanger). Freight is seperated into two queues on either side of the coastbound carriageway, one for tunnel traffic and one for port traffic. The middle lanes are kept clear for emergency vehicles.
Lorries are released at the request of the Port of Dover and Channel Tunnel. As we move them down the queue in stages you may see stretches of the motorway clear from time to time. If Junction 8 to 11 reaches capacity, Highways England will use Manston Airfield to park Port of Dover freight.
When Op Stack is in place, go to the police checkpoint at Junction 8 (M20). Make sure you have plenty of food and water with you. Officers will direct you to the correct queue, you should turn off your engine and wait to be moved forward. As previously mentioned, if Junction 8 to 11 is full, Port of Dover freight will be directed to Manston Airfield and tunnel-bound freight will stay on the M20. When Manston Airfield is in use, you will see signs on the motorway directing you to the airfield, if you ignore them and go directly to the Port of Dover, you will be turned away immediately.
As Op Stack is implemented there will be a significant queue of freight traffic which needs to be seperated into two queues. To safely manage this, partners may close the slip roads leading to the port and the tunnel for a period of time.