Iron Gates I: Combining Power Generation and Navigation on the Danube

Shoals and rapids in the Danube’s Iron Gates section had long obstructed shipping while offering exploitable hydropower. Yugoslavia and Romania selected a joint development between Sip and Gura Văii, combining navigation improvements and electricity supply. Tito and Gheorghe Gheorghiu-Dej signed an agreement in Belgrade on 30 November 1963. It entered into force on 16 July 1964 after the exchange of ratifications.

The treaty assigned half the investment to each country and divided available water energy equally throughout the project’s working life. At signature, estimated investment was approximately four hundred million U.S. dollars, including compensation for property losses caused by the reservoir. A joint commission provided continuing coordination so construction on each side served the overall system.

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Iron Gates I spans the Danube. Its layout is broadly symmetrical about the river’s center, with a powerhouse and lock on each bank and a spillway between them. The 1963 agreement required identical technical parameters for the two power stations and the two locks. Lock chambers had usable dimensions of 310 meters by 34 meters; vessels crossed the difference in level as water rose or fell within the chambers.

The agreement included a road across the dam, improvements to the downstream riverbed and reservoir-bank protection. It also required construction arrangements allowing a future railway. Locks, road and improved channel formed the transport facilities of the combined power and navigation system.

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The countries held a formal construction-start ceremony on 7 September 1964. Belgrade’s Energoprojekt was the principal design organization on the Yugoslav side, with Vukadin Đorđević involved in overall design. Bucharest’s hydropower design institution ISPH handled Romanian design. Pantelija Jakovljević led the Yugoslav construction enterprise; collaborating contractors carried out civil works, while manufacturers at home and abroad supplied and installed equipment.

Each country established design and investment-implementation bodies, coordinated through the joint commission. Preliminary design had to include technical and economic justification, equipment parameters, overall investment estimates and a master construction schedule, with approval by both governments. Cooperation thus took practical form in drawing approvals, quality inspections and coordinated progress.

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Construction began along both banks. Temporary cofferdams isolated parts of the bed; after pumping out water, workers excavated foundations and built concrete and reinforced-concrete structures. The central channel continued carrying water and vessels. As riverside structures advanced, that space narrowed, making navigation arrangements part of construction planning.

The second stage moved to the river’s center. Large stones and concrete elements formed upstream and downstream cofferdams. Workers pumped out the enclosed area and completed the remaining spillway sections, directing flow through built passages. Heavy rain and local flooding affected the 1969 river closure. The completed Romanian lock carried shipping around the central construction area during this stage.

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Locks carried traffic before all generating units were complete. In 1970, the first units began trial operation and supplied electricity to the grid. Others were installed progressively before the formal inauguration on 16 May 1972. Construction, partial use and full inauguration were successive delivery stages.

The first Yugoslav unit began trial operation in July 1970 and connected to the grid in August; the Romanian side also started its first unit that August. Remaining units entered use during the next two years. Construction, impoundment, navigation and generation had to be coordinated as the project moved into stable operation.

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Impoundment improved navigation while submerging or transforming riverside settlements. Residents of Orșova and nearby villages had to move, affecting homes, workplaces and family and neighbourhood relations. Replacement housing did not recreate former gardens, space for livestock or familiar public life.

A displacement study published in 2023 combined archives with a 2016–2017 survey of 350 residents in four communities. It records inadequate compensation, inconvenient housing locations and interrupted ways of life. Experiences varied: some respondents retained incomes or valued their new location, while others incurred house-building debts. Iron Gates I left both power and navigation infrastructure and social consequences requiring adaptation across generations.

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