Students of the Elsterschloss secondary school in Elsterwerda were forced to evacuate the school building on Wednesday, a police spokesman said.
In Bad Liebenwerda, the water level had already exceeded the maximum stage four flood alert by 30 centimetres. According to the state's Environment Ministry, the situation was intensifying in that town, with flood waters spilling over the dykes.
“This is no normal flood. We have the highest-ever measured water levels on the Elster,” said ministry head Matthias Freude.
In places the flood waters could no longer be contained, making evacuations unavoidable, he said.
In particular danger was the area around the town of Pulsnitz in Saxony and the Schwarzer Elster River.
More than 800 emergency workers have been deployed and 150,000 sandbags transported to the area to contain the rising water.
The head of Ministry for the Cottbus region, Wolfgang Genehr, described the situation as “extremely critical.”