Load boat (4)
I believe the answer is:
raft
I believe this is a double definition.
'load' is the first definition.
(both can mean a large amount)
'boat' is the second definition.
(I've seen this before)
(Other definitions for raft that I've seen before include "Flat floating craft" , "water transport" , "Structure that floats" , "host" , "Flat structure for travel over water" .)