19.—(1) No part of the authorised development may commence until there has been submitted to and approved in writing by and deposited with the relevant planning authority, in consultation with the Environment Agency, a scheme for mitigation of flood risk during the construction and operation of the authorised development prepared in accordance with the principles set out in section 14.7 of the environmental statement and the flood risk assessment annexed to the environmental statement. In particular it must include details of construction compounds and storage of materials to be located in areas of low flood risk and for access and egress from the construction or operational site of the authorised development to land above flood levels in the event of inundation.
(2) The approved scheme must thereafter be fully implemented and adhered to throughout the period of the construction and operation of the authorised development.