About Tresna Dam

The Tresna reservoir on the Soła river in Lesser Poland holds 92.7 million cubic metres and was completed in 1966 as the uppermost of three cascading reservoirs on the Soła: Tresna, Porąbka, and Czaniec. The 46-metre concrete and earthfill dam near Bielsko-Biała impounds the Soła river in the Beskid Mały foothills, creating a reservoir that extends 12 kilometres upstream into the Beskid Śląski mountains. The Soła cascade was built to harness the hydroelectric potential of the steep Carpathian rivers flowing north from the Silesian Beskids and to provide water supply and flood protection for the Bielsko-Biała and Oświęcim industrial areas. Together the three reservoirs generate approximately 92 megawatts of hydroelectric power. The Tresna reservoir is operated by Tauron Polska Energia and forms part of the Vistula catchment flood management system. The Żywiec basin upstream is known for its traditional Highlander (Góral) culture, breweries, and landscape of forested mountains and valley villages. Tresna's relatively clean Carpathian water and scenic setting attract sailing and recreation. The adjacent Żywiec brewery draws significant tourist interest to the region. Otters have been documented returning to the Soła river below the dam as water quality has improved following industrial restructuring in the region.