First, the means to build
The project was approved in September 1954. Roads, housing, production bases and an external power supply were needed before generation could begin. A line from Irkutsk initially powered construction; the unbuilt station could not supply its own works.
1957 and 1959 are not the same event
On 30 March 1957, the right-bank channel was closed from the ice to form the construction pit. On 19 June 1959 came the final closure, routing water through temporary dam openings. Excavation and the first foundation concrete of 1958 lay between them. Calling both simply “the closure” obscures the engineering sequence.
Power before final commissioning
The first unit supplied power on 28 November 1961. Installation, construction and controls continued: the central control room opened in 1964 and the last unit came under load on 14 December 1966. The complex was accepted on 8 September 1967. First power and final completion answer different questions.
The dam as a route
Trains and road vehicles crossed the crest in 1965, making an energy structure part of the city’s transport system. The 1960–1961 photographs show construction in progress, not the earlier operation on the ice.
