How awful finding limb in river (4,2)
I believe the answer is:
dear me
'how awful' is the definition.
(both can be expressions of dismay)
'limb in river' is the wordplay.
'limb' becomes 'arm' (arm is a kind of limb).
'in' is an insertion indicator.
'river' becomes 'dee' (River Dee).
'arm' inserted inside 'dee' is 'DEAR ME'.
'finding' is the link.
(Other definitions for dear me that I've seen before include "Expression of dismay" , "how distressing!" , "What a pity" , "Expression of mild regret from precious self" , "Mild expression of distress from expensive self" .)