The Armed Forces are to send a total of 300 soldiers and officers to the hardest hit areas around Hallsberg, Nässjö and Norrköping in central and eastern Sweden.
Explaining the move, Infrastructure Minister Åsa Torstensson described the current situation as the worst since the Swedish railroads were built.
"For the first time, the rail administration will receive help from the army," she told reporters at a Tuesday press conference.
Torstensson added that the army's presence would enable the 1,400 rail administration staff currently on duty to be deployed to the areas where they are most needed.
Asked why the rail administration had waited so long to call on the army, Director-General Minoo Akhtarzand replied:
"Our contractors have worked hard and tried to handle the problems, and we hoped the weather would improve but now we need some breathing space," she said.
Rail authority spokesman Clas Lundstedt said complications were likely to prevail on the rail network "for the rest of the week".