More than 20,000 residents were moved as rivers burst their banks with forecasts of worsening flooding later this week.
The swollen Amur River reached a depth of 910 cm near Komsomolsk-on-Amur on Sunday, with fears it could hit 940cm.
The Amur River rises past 7.35 metres in Khabarovsk city, with Komsomolsk-on-Amur, and Nikolayevsk-on-Amur also braced for new flooding.
Russian army in battle to erect dikes to hold back the swirling Amur River as evacuations begin in low-lying areas.
Trans Siberian trains are on schedule despite rivers breaking their banks and plans to evacuate the gateway of Khabarovsk.
Damage from wave of floods already labelled 'catastrophic' with worse to come as Russian president Vladimir Putin demands: 'Put people first'.
Flooding now covers an area almost as large as France, Germany and Britain combined, or close to the equivalent of Texas and California.
Defences were breached in Komsomolsk-on-Amur engulfing several villages, as forced evacuation rise.
Many residents have refused to leave their homes because of the worst flooding since records began.
More flooding misery due to burst dam as experts say the cause is global warming.