The Government Says

Memorandum of Understanding between NDA and Environment Agency

Memorandum of Understanding between NDA and Environment Agency
Local copy of Memorandum_of_Understanding_NDA_and_EA_Sep2024.pdf

https://www.gov.uk/government/publications/memorandum-of-understanding-between-nda-and-environment-agency

seen at 14:40, 26 March in Transparency and freedom of information releases.