Eight children and three adults had to be rescued after their speedboat started sinking off the Herne Bay coast in heavy winds.
Whitstable Lifeboat and Herne Bay Coastguard launched a joint rescue effort on Sunday afternoon after mayday calls were received just after 4pm.
A local rigid inflatable vessel was the first to arrive on scene and rescued the children and one of the adults. Whitstable Lifeboat’s crew then helped rescue the remaining passengers.
Lifeboat helmsman Dave Parry said: "Crew members Tony Martin and John Skinner then went aboard the casualty craft and began to bail it out using their crash helmets and a large plastic box.
"Once most of the water had cleared the lifeboat took the speedboat under-tow and the Coastguard’s rigid inflatable then proceeded ashore with the remaining occupants of the stricken speedboat.
"Some of the children were by now very cold and an ambulance was requested to attend the scene. Three of the children were subsequently found to be hypothermic and received treatment from paramedics."