In the historic Baden-Württemberg town of Wertheim, officials ratcheted up their high water forecasts for the Main and Tauber rivers as levels continued to surge.
At 5 am on Wednesday water gauges registered 5.72 metres, already ahead of the 5.7-metre level predicted for midday, a fire department spokesperson said. Officials in Wertheim, where the mediaeval city centre has been submerged for more than a day, said they expected river levels to reach 5.9 metres before noon.
Some 450 homes with 1,000 residents have been affected, with rescue workers setting up a nine-boat transportation system for commuters.
Upriver in Frankfurt am Main, rescue workers were reportedly building makeshift dams to protect the city's central Römerberg square from the rising Main River.
In the east icebreakers remained in constant operation along the Oder River, helping to significantly lower water levels by clearing a number of blocked tributaries.
The Spree and Elbe rivers were also reportedly receding, but along the Schwarze Elster the situation remained critical, with water levels reaching the highest alarm level near Herzberg in the state of Brandenburg.
Flood watch officials in the state of Saxony-Anhalt also reported dramatically high water levels along rivers as residents braced for rain in the forecast.