45 karst caves have been discovered on the Second Track

The 45th karst phenomenon has been discovered on the Second track. Each karst feature encountered during construction is thoroughly examined, inventoried and photographed by the Karst Research Institute. Such discoveries have so far mostly not hindered tunnel construction.

The latest karst cave was discovered during the excavation of the main pipe of the Lokev tunnel (T1) from the direction of Koper. In it, karstologists found stalactites, stalagmites and sigma curtains. In some places, the bottom of the cave is completely covered by flood clay, which means that the cave is flooded at certain times of the year. The cave is 45 metres high and 77 metres long, but karstologists expect that further research will show that it is even larger. No external animals, such as bats, have been observed in the cave, which means that the cave is not connected to the surface.

Expectations before the start of the construction of the Second Track were that 100 minor and 10 major karst features would be found in the distinctly karst terrain where the Lokev and Beka tunnels are being built. The two tunnels are also the longest tunnels on the route, at more than six kilometres. The contractors still have to excavate about two kilometres of both tunnels.

Photo: Karst Research Institute