This paper investigates the juncture of hydropower and nuclear engineering  traditions in the form of energy complexes in the Soviet Union during the 25-year-period of 1966-1991. During this period, the USSR tried to stimulate its economy with cheap electricity to counter economic stagnation. Communist politicians brought forth a grand-scheme nuclear agenda to address this issue. It encapsulated the civil nuclear industry as the symbol of societal progress. The promise of abundant and cheap electricity would re-fuel the ailing  economy, demonstrate the technological strength of the country and prove to its own people that concrete steps were being taken towards the realisation of communism. 

Soviet engineers from the hydrotechnical institute Gidroproekt envisioned the creation of energy complexes, in which a nuclear power plant would provide the energy grid's baseload, while accompanying hydropower plants would contribute the peak-demand-regulation. By combining these two means and functions in electricity production, irrigation for agriculture and the yield of local fisheries could be improved. These complexes were planned to be large (5-10 GWe) and symbols for Soviet imaginaries of Socialist progress. By thus combining older hydraulic with newer nuclear traditions, these complexes signified a Soviet approach to coping with electricity shortages in a context of economic struggle. 

The article makes use of archival planning material from Gidroproekt and Minenergo. This is done to illustrate how Soviet nuclear and hydraulic engineers created plans for three energy complexes. At the Southern Ukrainian, Rozhnyatovskij and Kolskij energy complex the technocratic mixture of hydraulic and nuclear traditions manifested itself in remarkable attempts to change the natural environment – as envisioned proof of Soviet technological superiority.