Hundreds more people were being evacuated from their homes in Wales yesterday in a new flooding alert – just as others were going home after being inundated yesterday.

Breach may have been caused by a landslide

North Wales Police evacuated residents from the village of Pennal, near Machynlleth, Powys, following a slight breach in the dam of a local reservoir which caused a small amount of water to escape.

A police spokesman said residents were being transported to Machynlleth Leisure Centre.

“Staff from the local councils, representatives from the local water board, North Wales Fire and Rescue Service and officers from North Wales Police are at the scene working to stabilise the situation,” she said.

“At this current time it is thought that the breach may have been caused by a landslide.”

Superintendent Andy Jenks-Gilbert said the evacuation was taking place as a precautionary measure. A crack had been found in a stone wall at the reservoir and a small amount of water had escaped, he said.

“Should the wall be completely breached, the contents of the reservoir will go into the river which flows through the village of Pennal, which is around half a mile from the reservoir. Police officers are evacuating residents in the area and would ask visitors and locals to avoid the village at this current time.”

The drama came as hundreds of people evacuated following flash flooding 20 miles away were returning to their homes and caravans. Villages in the county of Ceredigion were flooded by up to 1.5 metres of water yesterday.

Some 150 residents and holidaymakers were rescued and evacuated from homes and caravan parks near Aberystwyth after twice as much rain fell in 24 hours as normally falls in the area in the whole of June.

Fire crews were again working around the clock, continuing to pump out water from a number of locations. Although many roads have reopened, a flood warning remained in place.

A number of caravans and tents in the Aberystwyth Holiday Park remained cut off from land.