Operation Stack
Operation Stack was a contingency procedure coordinated by Kent Police and Highways England to manage queues of heavy goods vehicles (HGVs) on the M20 motorway in Kent, England, during disruptions to cross-Channel freight services at the Port of Dover and Eurotunnel Folkestone.[1][2]
Introduced in 1988 following ferry disruptions, the protocol involved closing coastbound lanes between junctions 8 and 11—or sometimes the entire motorway—to form static HGV convoys, while diverting cars, local traffic, and non-freight vehicles onto parallel A20 routes or other roads, often leading to gridlock across southeast England.[3][4]
Its frequent activation, including a record 32 days in 2015 amid migrant incursions and strikes at Calais, underscored reliance on short-sea freight links but provoked substantial controversy over economic losses to Kent businesses—estimated at £1.5 million daily—and severance of local communities from essential travel.[5][4]
By 2019, Operation Stack was largely replaced by Operation Brock, incorporating contraflow systems and off-motorway holding facilities like Manston Airport to sustain bidirectional traffic flow and reduce regional disruption.[6][7]