In message , Andrew Mawson
writes

As I understand it, on agricultural land, you can change levels up to 1
Metre without needing planning permission. I cannot quote chapter and
verse, but no one has challenged me having raised 3/4 acre by 30 inches
8 years ago

Don't do it on the flood plain and you need the appropriate EA waste
exemption. U10 is a good one:-) (spreading waste to benefit agricultural
land)

EA has an input to what happens within 8m of a non navigable waterway.

--
Tim Lamb