This was mentioned in House of Commons debate where they were asking for 8 million ponds to fix it:
"In June 2003, Southend experienced a disaster whereby land slip occurred on four sites, all of which were located along the frontage to the Thames estuary, set back from the water line behind the main road frontage. The largest of those occurred at a location known as the bandstand, which resulted in the ground slipping some 14 m and the destruction of buildings in the vicinity."
Roads - Misc 
This was mentioned in House of Commons debate where they were asking for 8 million ponds to fix it:
"In June 2003, Southend experienced a disaster whereby land slip occurred on four sites, all of which were located along the frontage to the Thames estuary, set back from the water line behind the main road frontage. The largest of those occurred at a location known as the bandstand, which resulted in the ground slipping some 14 m and the destruction of buildings in the vicinity."