[4][5] The plant operated ten type РО-230/833-0-677  hydro turbines[6] manufactured at the Leningradsky Metallichesky Zavod, each with a capacity of 640 MW at 194-metre (636 ft) head.

[12] In years of heavy rainfall, about 1,600–2,000 GWh are lost due to lack of high-voltage line transmission capacity, and some water bypasses the turbines.

[4] The plant was designed by the Leningrad (now Saint Petersburg) branch of the Hydroproject (Гидропроект, Gidroproyekt) institute, Lenhydroproject.

In April 2003, the Government of Khakassia by the initiative of the governor Alexei Lebed filed a suit to invalidate the deal.

[16] In 1998, the Russian Emergency Situations Ministry claimed that the "station construction [had] dangerously changed" and that the dam wall might not withstand the repeatedly increasing pressures of the annual spring floods.

In 1993 the French company "Soletanche Bachy" impregnated dam constructions with resins after which the filtration was reduced and situation improved substantially.

[19] In 2004, BBC Monitoring quoted a Russian TV news report as saying that the dam operators had been forced to construct an extra water intake wall to alleviate the spring flood pressures.

[20] On 8 September 2009, the Accounts Chamber of the Russian Federation disclosed that the power station was audited in 2007 and that 85% of all technological equipment needed to be replaced.

[25] Consequently, most of the water influx into the reservoir must be drained through a poorly designed spillway, which previously had already suffered extensive damage as a result of spring floods in 1985 and 1988.

[26] While it would be possible to increase the spillway drain to 7,000–7,500 m3/s, such an operation was previously deemed unsafe to the structure,[27] and could result in further erosion of the dam's already weakened foundation even as the reservoir continues to fill.

The damage would occur by direct impact of the falling water to the spill well (which, once its concrete slab lining were destroyed, would expose and erode the dam's bedrock support) as well as by intense vibrations created by the waterfall, which the concrete dam, lacking steel reinforcement, is not designed to withstand for prolonged periods.

The resulting flood wave, which could be from 50 to 200 m high near the breach and moving at up to 200 km/h, would destroy the downstream Maynskaya HPP in a matter of minutes; the nearby town of Sayanogorsk would be flooded in under half an hour, and the heavily populated area including Abakan and Minusinsk (altogether more than 200,000 people)—within 40 minutes to several hours.

After reaching the Krasnoyarskaya HPP further downstream, the flood wave would rise its reservoir by roughly 10 m and spill over its dam, destroying the power plant machinery.

If that dam should fail too (the possibility of which exists in this scenario), the resulting mass of water could wash away the city of Krasnoyarsk and its suburbs, drowning or displacing their population of over 1,000,000.

[32] A powerful spring flood destroyed 80% of the concrete spillway bottom plate, tearing apart 50-millimetre (2.0 in)-thick anchor bolts and carving seven meters deep into the bedrock.

[13] On 17 August 2009 at 8:13 AM, the hydro-electric plant suffered a catastrophic accident that caused flooding of the engine and turbine rooms, and two 711 MVA electric generators to explode underwater as a result of a short circuit.

[5][33][34] As of 10 September 2009[update], 75 people, including 1 pregnant woman, were confirmed dead, while one person was still listed as missing forty days after the disaster.

Under the 20 atmospheres of water pressure, the spinning turbine, with its cover, rotor, and upper parts, jumped out of the casing, destroying the machinery hall, the equipment in it, and the building.

It took 25 minutes to manually close the water gates to the other turbines; since the power distribution equipment was destroyed, during that time, they continued to spin without load.