Montenegro is exploring the potential use of its portion of Bilećko Lake for both water supply and hydroenergy projects, according to updates in the Spatial Planning Document (PUP) for the Municipality of Nikšić, which was approved by the government in June.
The revised plan indicates that Montenegro could harness a part of Bilećko Lake—covering 4.82 km² of Montenegrin territory, with an estimated volume of 300 million cubic meters—for providing water to the karst areas of Banjani and for hydroenergy production. The proposal includes constructing water intake facilities within Montenegro and utilizing the lake’s water for hydroenergy by building dams and reservoirs on the Kunska River and Zaslapnica, tributaries of Sušica, with a total projected volume of around 20 million cubic meters.
The plan suggests that water from Bilećko Lake could be channeled through hydrotechnical tunnels to these reservoirs. Subsequently, the water would flow back into the Sušica River system and into the Gorica compensation basin, potentially reducing flood risks.
The authors of the document, a working team from the Ministry of Spatial Planning, highlight that while leveraging Bilećko Lake’s water for a hydroelectric plant in Montenegro could be advantageous, it would decrease the current output of power plants relying on this water. They stress the need for detailed studies and agreements with neighboring countries to advance such complex water management projects.
Since 1968, Bilećko Lake has been providing electricity to Bosnia and Herzegovina and Croatia through the Trebišnjica hydroelectric system, including the Trebinje 1, Trebinje 2, Dubrovnik 1, and Čapljina plants. Although approximately 40% of the lake’s water originates from Montenegro and about one-fifth of its surface lies within its borders, Montenegro has yet to receive any compensation for the energy produced. Following prolonged negotiations, a retroactive compensation agreement for submerged land was finalized for the Municipality of Nikšić in late May.
In mid-June, during a meeting between Montenegro’s Energy Minister Saša Mujović and Luka Petrović, Director of Elektroprivreda Republike Srpske (ERS), the possibility of Montenegro utilizing part of Bilećko Lake’s potential for hydro and solar power was discussed.
The PUP for Nikšić also proposes addressing water supply challenges for the Rudina and Banjani areas through a regional water supply system that would draw from Bilećko Lake and Slansko Oko. The specific methods, quantities, regimes, and other conditions for water intake are to be defined in subsequent project documentation and agreements with neighboring countries.
The document further explains that the Municipality of Nikšić includes part of the Trebišnjica River basin, with sections submerged by Bilećko and Miruško Lakes. The basins of the Nudolska River, Zaslapnica and Kunska River are within the Municipality of Nikšić.
Bilećko Lake was created on the Trebišnjica River in its source area with the construction of an arch dam at Grančarevo between 1961 and 1967. The dam’s base is at an elevation of 296 meters, with a height of 107 meters. The lake extends 18 km from the dam to the Bilećki springs, covering a total surface area of 20 km². A 10 km section of the lake forms the border between Montenegro and Herzegovina, leading to the relocation of the Kosijerevo Monastery and a significant portion of the local population. The Grančarevo hydropower plant generates approximately 495 GWh of electricity annually.
