December 31, 1911 Tsunami: Folkstone, England, United Kingdom

Reference #14326:

1911, Dec 31. A very large landslide at Abbot’s Cliff east of Folkestone caused a wave in Folkestone Harbour that was most notable in the shallow areas. Ropes and stanchions were damages as hawsers snapped. The event was described in the Folkestone, Hythe, Sandgate and Cheriton Herald of Saturday 6th January 1912 by a seaman (Charles Harrison) who was standing on the harbour as:- “The great rush of water swept up towards the harbour from the east without the slightest warning. I have never witnessed anything like it. The sea was choppy, but not rough, previously. All at once there seemed to be a long heaving, lifting motion, as if the Channel were being raised in the air. The vessels in sight ‘danced’ violently, the colliers were tossed pell mell, and the crews on various steamers lying around shouted at the tremendous shock. It was an exciting moment – for it passed in a moment – and left us all wondering”.

The newspaper article notes vessels were lifted two to three feet (0.6 -0.9m) by the wave. The effects in the outer (deeper) harbour were minimal.

It was speculated that heavy rains over the preceding months had weakened the cliff, causing the rockfall leaving the debris at the foot of the cliff (Figures 8 and 9). The cliff was previously 348ft high here (McDakin, 1912). Hutchinson (2002) gives a volume of 500,000m3 for this fall.

This landslide is unlike at the nearby landslides in the Warren which consist of rotational slides on the Gault. The extensive volume of fallen rock has remained at the foot of the cliff extending into the sea. The sea between Abbot’s Cliff and Folkestone harbour is shallow, less than 10m, so the wave would have moved relatively slowly.