Danger of pier collapsing by lake (5)
I believe the answer is:
peril
'danger' is the definition.
(synonyms)
'pier collapsing by lake' is the wordplay.
'collapsing' indicates anagramming the letters.
'by' is a charade indicator (letters next to each other).
'lake' becomes 'L' (geographical abbreviation).
'pier' with letters rearranged gives 'peri'.
'peri'+'l'='PERIL'
'of' acts as a link.
(Other definitions for peril that I've seen before include "Danger, jeopardy" , "risk" , "Immediate danger" , "Danger of serious kind" , "Exposure to harm" .)