Officials have warned of dangerous water levels in the Ural River and will investigate the dam breach.
Russia says more than 4,000 people have been evacuated from the Orenburg region near the border with Kazakhstan due to flooding caused by a burst dam.
The Orenburg governor's office said on Saturday that “4,208 people, including 1,019 children” had been evacuated and more than 2,500 houses were affected by the flooding, which led to the construction of a dam following Friday's downpour.
Governor Denis Basler said the flooding had reached its “peak” and the situation in the border town of Orsk, home to 230,000 people, was particularly difficult.
About 2,000 people were forced from their homes in Orsk alone, officials said Saturday. Orsk is located in the Orenburg region of the Ural Mountains.
But officials said the situation remained difficult across the region and warned of dangerous water levels in the Ural River in the main city of Orenburg.
Video footage released by the Ministry of Emergency Services showed residents donning life jackets and helping themselves to lifeboats. Russian news agencies reported that thousands of homes were submerged.
Russia also opened a criminal case for “negligence and violation of construction safety rules” over the blast dam built in 2014.
According to Russian news agencies, the local prosecutor's office said the dam broke due to poor maintenance.
Much of the Urals and western Siberia have been affected by early spring flooding, and parts of Kazakhstan have also been affected.
Kazakhstan President Kassym-Jomart Togayev said the flood could be Kazakhstan's biggest natural disaster in 80 years in terms of size and impact.
“We have to learn all the lessons from these large-scale floods,” he said.