Civil Defence says a state of emergency will remain in place for the Marlborough region until at least Thursday afternoon.
An emergency was declared by the Marlborough District Council on Wednesday afternoon.
Civil Defence Controller Mark Wheeler, told Morning Report it was done to enable police to force unwilling residents to leave their homes.
Some 35 people in Picton were evacuated on Wednesday night from a camping ground and from houses near a flooded creek.
They spent the night in the auditorium of Queen Charlotte College. Red Cross volunteer Sam Morrison told Morning Report their morale is good.
Checks will be made at first light for flooding and fallen trees in the town.
