Kitzbühel bans swimming in Schwarzsee after algae levels rise

Kitzbühel has banned swimming in Schwarzsee, a lake, after blue-green algae levels rose sharply in recent days, ORF reported. The ban has been in force since Tuesday, and the municipality has also warned people not to let dogs drink the lake water.

A warning had been issued over the weekend, but the rising algae levels prompted a full swimming ban.

Just weeks earlier, Schwarzsee had been reported to have excellent water quality. Drinking water was added to the lake, algae were mowed, and a deep drainage pipe was intended to draw oxygen-poor water from its lower layers. The lake is up to seven metres deep.

Blue-green algae levels have risen sharply several times in recent years. They increased again as high temperatures receded.