* Putin compares Russia's accident rate to "war zone"
* President Medvedev tells Putin to prevent power cuts
(Adds quotes, context and details of rescue and funerals)
By Darya Korsunskaya and Denis Dyomkin
MOSCOW, Aug 20 Prime Minister Vladimir Putin called for a sweeping probe of Russia's creaking Soviet-era infrastructure on Thursday after a disaster at its largest hydroelectric power station.
A water surge caused ageing turbines to explode at a 31-year-old Siberian dam on Monday, starting a chain reaction that sent a cascade of water into a 100-metre (yard) turbine hall and the four floors below it, and dumped 45 tonnes of fuel oil into the Yenisei River below.
The confirmed death toll stands at 17, but most or all of the 58 people listed as missing are also likely to be dead.
"The tragic events at the Sayano-Shushenskaya power station showed with full clarity how much we need to do to improve the reliability of our engineering structures in general," Putin told a meeting of the government.
"A serious review of all strategic and vital infrastructure is required," said Putin, who was to travel to the site of the disaster on Friday.
Few of Russia's roads, bridges or railways have been upgraded since Soviet times; the turbines at the plant were designed to last no more than 25-30 years, but were still in place 31 years after the colossal dam opened.
Analysts say Moscow has fallen behind its emerging market rivals in infrastructure investment -- Russia's roads alone claimed 30,000 lives last year.
"What happens on our roads is like a report from a war zone -- and the same is true of work at sophisticated technical facilities," Putin told the cabinet.
Rescue workers used dogs, cranes and power saws to search for missing workers in the turbine hall on Thursday. The wreckage of the giant turbine was submerged in a brown sludge that will take three days to pump out, according to the Emergencies Ministry.
Rescue officials said they had no news of the 58 missing.
Over a thousand people gathered around the open coffins of dead workers at a memorial service in the nearby town of Cheryomushki on Thursday. Relatives embraced in front of wooden crosses with the names of the dead.
Rubber booms were placed in the river to catch the spilled oil as the World Wildlife Fund said local reports indicated that up to 400 tonnes of fish had been killed by the slick.
Natural Resources Minister Yuri Trutnev said there were "no grounds to speak of an ecological catastrophe".
President Dmitry Medvedev ordered Putin's government to establish the cause of the accident and take measures to deal with its consequences within two weeks.
He said the government should provide uninterrupted energy supplies to industrial enterprises, social institutions and the general population, and prevent any price spikes for consumers in Siberia.
The Russian hydroelectric power monopoly RusHydro will not raise its tariffs to compensate for costs incurred repairing the dam, sales director Yevgeny Desyatov said in a conference call.
The world's biggest aluminium producer, UC RUSAL, has said it could lose 500,000 tonnes of aluminium production, equivalent to 11 percent of last year's output, because of power shortages likely to result from the accident.
The Sayano-Shushenskaya power plant, which accounts for a quarter of RusHydro's output, is expected to be closed for several months.
RusHydro (HYDR.MM) shares rose 0.9 percent in Moscow after falling 11.2 percent on Wednesday. The accident has cut its market value by about $1.5 billion. (Additional reporting by and Anastasia Lyrchikova, writing by Conor Humphries; Editing by Kevin Liffey)