The blaze, which was attended by about 50 firefighters from both East and West Sussex, broke out at about 8.30pm yesterday (March 1).
The immediate area, though not nearby homes, was evacuated, and two people on a small boat in the vicinity were told to leave.
Supt Grenville Wilson of Sussex Police said: “Thankfully, there have been no reports of injuries and the sterling work carried out by our colleagues in the fire service enabled a fairly early decision that a large scale evacuation would not be necessary.”
He added a police presence was maintained over night.
*The infra-red photo of the scene was taken by the Sussex Police South East Air Support Unit helicopter Hotel 900.