Kölnbrein Dam

The Kölnbrein Dam stands in the Hohe Tauern range of Carinthia, a high arch dam built between 1971 and 1979. It rises 200 metres above the Malta Valley floor, making it Austria’s tallest dam. The dam holds back a reservoir that feeds a large pumped-storage system with nine dams and four power plants. Owned by Verbund, the whole plant group is called the Malta-Reisseck Power Plant Group. Its installed capacity reaches 1,028.5 MW, generating over 1,200 gigawatt-hours each year. The dam’s construction faced serious challenges soon after it began holding water. Cracks appeared when the reservoir reached 42 metres below its planned maximum level. Engineers discovered unexpected uplift pressure and damage to the grout curtain. Repairs took more than a decade, including a 70-metre thrust block added at the downstream base in the early 1990s. Over 600 neoprene pads and resin grouting finally allowed full operation in 1993. Visitors reach the dam along a winding access road cut through the valley’s steep slopes. Six tunnels ease the climb up the 300-metre rise over 14 kilometres. The dam itself is a sweeping concrete arch, its massive columns and joints now stabilised by modern materials. From the crest, views stretch across the reservoir and up the surrounding peaks. The power plant complex lies just downstream, where water is channelled through tunnels and penstocks to generate electricity. The valley below shows the scale of the system, with smaller reservoirs and pipelines linking each stage of the scheme.