The explosion at around 17.00 local time on Monday came during painting works at plant on the Yenisei River upstream of the city of Krasnoyarsk.
A spokesman for En+ Group said: 'The Krasnoyarsk hydropower plant operates in the routine mode'. Picture: Denis Belevich
The 124 metre dam was not damaged and there was no disruption to power generation. The Russian Investigative Committee for Krasnoyarsk region was carrying out a preliminary investigation. A special commission was formed which 'will make public the data about the incident later'.
A spokesman for En+ Group said: 'The Krasnoyarsk hydropower plant operates in the routine mode'.
The plant is in Divnogorsk, around 30km upstream of Krasnoyarsk city.
Archeologists discovered a new stone bracelet, two sharp pins, a marble ring and fox tooth pendants.