Emergency teams of workmen were fighting to combat the worst oil slick contamination in the upper reaches of Portsmouth Harbour for years.
Up to 100 private fishing boats were coated in oil, and an angling club’s man-made sand beach was destroyed.
For two days, dockyard vessels sprayed detergent on the slick to disperse it – and at first it was thought their work was successful.
But it became clear much of the heavy oil had escaped the spraying operation – and had flooded into the Rudmore area of Fountain Lake.
So much oil had landed on the beaches and foreshore at Rudmore that Portsmouth Corporation was backing up its already large-scale operation with an excavator and lorries to take away the oil-soaked flotsam.
A spokesman for the harbour office said the spillage was traced to the Brittany Ferries ship, Breizh-Izel.
She was a freighter which normally ran on the Roskoff-Plymouth route, and she arrived in Portsmouth on relief for the first time.
During fuelling one tank overflowed and between two and four tons of oil leaked into the harbour said the spokesman.