Rescue workers searched flood-ravaged parts of western Germany for survivors as water levels remained high in many towns and houses continued to collapse in the country’s worst natural disaster in half a century.

At least 180 people have died in the flooding, including some 110 in the Ahrweiler district south of Cologne. In neighbouring North Rhine-Westphalia, Germany’s most populous state, 45 people were confirmed dead, including four firefighters. Hundreds of people are still missing.

The flooding has also hit parts of Belgium and the Netherlands. At least 27 people have died in Belgium.

Over the past several days the floods, which have mostly hit the German states of Rhineland Palatinate and North Rhine-Westphalia, have cut off entire communities from power and communications.

About 700 residents were evacuated late on Friday after a dam broke in the town of Wassenberg near Cologne, authorities said.

Chancellor Angela Merkel was due to visit Schuld, a village near Ahrweiler that was devastated by the flooding, on Sunday.

German President Frank-Walter Steinmeier and Armin Laschet, state premier of North Rhine-Westphalia, visited Erftstadt, one of the hardest hit towns, on Saturday.

Laschet is the governing CDU party’s candidate in September’s general election. The record rainfall recorded and the devastation of the floods could intensify the debate over climate change ahead of the vote.

Scientists have long said climate change will lead to heavier downpours. But determining its role in these relentless downpours will take at least several weeks to research, scientists said on Friday.