The contingency traffic management measures of Operation Brock consist of three phases: a queuing and contraflow system between junctions 8 and 9 of the M20 (Brock M20); temporary holding areas at Manston Airport; and, if necessary, temporary holding areas on the M26 (Brock M26), if capacity has been exceeded elsewhere within the Brock suite of measures.
As part of the design process of the Operation Brock measures, Highways England undertook legally required environmental screening exercises. These determined that full Environmental Impact Assessments were not required for either the Brock M20 or Brock M26 measures. The formal Notices of Determination were published in The Gazette on 24 May 2018 and 15 November 2018 respectively.
For Manston Airport, environmental and habitat assessments were carried out to inform the conditions of the Town and Country Planning (Manston Airport) Special Development Order 2019 (SDO), which was laid before Parliament on 23 January 2019.