No part of the authorised development is to commence until for that part written details of the surface and foul water drainage plan, containing all relevant mitigation measures set out in the register of environmental actions and commitments including means of pollution control and monitoring and drainage operation, have been submitted to and approved in writing by the relevant planning authority following consultation with the Environment Agency, Kent County Council, Natural England and Southern Water on matters related to their function.

The surface and foul water drainage system must be constructed in accordance with the approved details, unless otherwise agreed in writing by the relevant planning authority following consultation with the Environment Agency, Kent County Council, Natural England and Southern Water on matters relating to their functions, provided that the Secretary of State is satisfied that any amendments to the approved details do not give rise to any materially new or materially different environmental effects from those assessed in the environmental statement.

No part of the authorised development is to begin operation until the construction of the entire surface and foul water drainage for that part is completed.

Construction of the attenuation basins must be completed within the first phase of construction if construction is undertaken in phases.