The village of Täsch, the gateway to the resort of Zermatt, had to be partially evacuated on Monday night after a stream broke its banks and flooded several areas. The flood waters came from a mountain lake above the village which had been swollen by melting snow.
The water reached Täsch late on Monday evening, washing away a bridge crossing the stream.
Up to 150 people had to leave their homes, and by Tuesday a dozen had still not returned.
The "Weingartensee", the lake which caused the flooding, lies above 3,000 metres. The layer of snow and ice which normally covers the lake's waters has melted over the past few days because of the current heatwave.
The water level dropped in Täsch on Tuesday, but the authorities have warned of possible further floods as temperatures rise again.
The service road which connects Täsch to Zermatt, one of Switzerland's major tourist destinations, has been temporarily cut off to facilitate repairs. There are no public roads. People wishing to travel to Zermatt have to leave their cars in Täsch and take a train to the resort.
Flooding has been a major concern in canton Valais. The village of Gondo was cut in half last year by a flash flood, killing 13 people.
swissinfo with agencies
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