
The Sea Alpha was towing the new 67m dipper dredger Goliath, carrying 138 cu m of fuel oil along with further lubricants and hydraulic oils, from Belgium to Killybegs, in Ireland.
At 0441 hours, the tug reported to Dover Coastguard that the unmanned dipper dredger was taking in water and they were attempting to sail into Dover Harbour.
But the approach into harbour was called off when it was seen that the dipper dredger was in danger of sinking, and the tug was directed to a shallower part of the bay.
The Dover Severn class all-weather lifeboat was launched just before 0500 hours and the Coastguard emergency towing vessel Anglian Monarch, 1,485gt, stood by.
The weather forecast for the area was southerly winds increasing to Gale Force 8 with squally showers and rough seas.
As the morning went on, it was clear that the dipper dredger was slowly sinking, and her engine room was now flooded.
The Goliath was pushed by the Sea Alpha into shallow water and beached between Deal and Kingsdown. The lifeboat stood by while the dipper dredger was beached.
Once the dipper dredger was ashore and the risk to the tug crew had passed, the lifeboat returned to station, but the Anglian Monarch remained close to the scene.