The urbanisation of Ukrainian society in the post-war years led to an increase in energy consumption. Between 1956 and 1972, to meet this increasing demand, the government built five water reservoirs along the Dnieper River. Aside from improving Soviet-Ukrainian water transport, the reservoirs became the sites for new power stations, and hydroelectric energy flourished in Ukraine in consequence. The natural-gas industry flourished as well, and Ukraine became the site of the first post-war production of gas in the Soviet Union; by the 1960s Ukraine's biggest gas field was producing 30 percent of the USSR's total gas production. The government was not able to meet the people's ever-increasing demand for energy consumption, but by the 1970s, the Soviet government had conceived an intensive nuclear power program. According to the Eleventh Five-Year Plan, the Soviet government would build 8 nuclear power plants in Ukraine by 1989. As a result of these efforts, Ukraine became highly diversified in energy consumption.