It's time to replace it so that it can once again perform its function without limitations. The inclined elevator on Čierny Váh hydroelectric power plant connects the power station with the upper reservoir. A unique feature that you will not find anywhere in Slovakia or the Czech Republic. At an angle of 45 degrees, in an environment with almost one hundred percent humidity, it makes its daily 598-metre long way to the upper reservoir, which at a speed of 39 metres per minute it crosses in about a quarter of an hour. Up until now, it has been used daily, with at least one round trip. The approximate estimate is 20,000 trips to the upper tank and back over the entire period of its operation.

It was built during the construction of the power plant, whose engine room was originally to be located in the mountain massif on top of which the upper reservoir is located. However, the results of the engineering geological surveys prior to the start of construction meant that the original plan was changed and the power station was eventually designed as part of the dam wall of the lower reservoir. The Katarína exploratory tunnel was cut so that it could be used as a construction object in the future, and in the final design it was used as a communication tunnel for the workers on the upper reservoir. In order to save material for the production of the feeder tunnels, but also from a nature conservation point of view, the designer proposed underground feeder tunnels. An exploration tunnel was located parallel to them, with a mutual axial distance of 30 metres between the feeder and the tunnel. The lower horizontal part of the Catherine was 515 metres long and had two lateral splays at the location of the identified geological faults. At its end, where the tunnel breaks abruptly to a 100% grade at a 45° angle, today you will find the lower station of the Alimak inclined lift.

The complex rock massif in the climatically demanding area of the Low Tatras on the Neznáma hill with an altitude of 1150 m is composed of geologically very close rocks - limestones and dolomites - but they have very different technical properties. A very detailed geological survey was therefore carried out right at the start of the project. In the field of rock work, technological procedures, drilling rigs, suitable ammunition and the quantity of ammunition had to be designed. As it was not possible to make do with conventional geological survey methods, the tunnelling method of exploration was used. In 1965, the project for the Katarína exploration tunnel, which was to be 200 metres long, was born. At this time, the possibility of building an underground power station was also being explored. The aim of the tunneling was to capture a possible geological fault and explore it directly.

The principle of its operation is basically the same as when you ride a toboggan in the Tatras. Two electric motors with two toothed combs roll along a toothed rail and pull the lift up or lower it down. The lift is, of course, equipped with a handbrake, which is normally locked. If necessary, it can be unlocked and the lift is gradually 'unbraked' as it descends. This means that it is lowered slowly and every 50 metres or so it comes to a complete stop, waits for the brakes to cool down and can continue. In this way, in the event of a sudden breakdown, the entire runway can be safely traversed to the down station. In addition to the handbrake, a so-called interceptor or catching device is installed in the lift. In the event of a motor failure and after the lift has accelerated downwards at an excessive speed, this works by applying friction to brake the lift until it comes to a complete stop.

Do you like taking the stairs?

Stairs run parallel to the lift. These serve as a route to the lower station in the event of an unplanned stoppage or failure of the lift. You can also go to the upper station, but it depends on where the lift has stopped and your fitness level. We haven't mentioned the elevation, which is 445 metres. It's okay to get over it in the lift. However, we don't recommend anyone without really great fitness to climb the stairs to get over it. We can reveal, however, that our current CEO took up the challenge a few years ago and ran them with a smile during a visit to Čierny Váh. We will only add that the staircases are unusually high and there are exactly 2320 steps.

Time for replacement

The Alimak U-500 inclined elevator, serial number 203, was manufactured in 1979 and has been in continuous operation since June 1980. After more than forty years of operation, when the lift no longer fully fulfils its role due to wear and tear, it is time to replace it. Originally it was also used for transporting materials up to the upper tank, with a lifting capacity of up to 1000 kg. A few years ago, due to heavy wear on the track from the running pulleys and after static calculations, its operation was limited to the weight of two adults only. Therefore, for the last few years the lift has been used only for the purposes of the power plant's service staff, for the regular performance of inspections on the upper reservoir, which is required by legislation, since Čierny Váh is a category one water structure, which means that the dam's colleagues here must check the points and probes on the upper reservoir every day, whether it is a weekend or a holiday, as part of technical and safety supervision. The replacement of the lift, for which spare parts are no longer available due to its age, has therefore been scheduled for the summer period so that alternative access to the upper reservoir by car is not restricted due to the abundance of snow, which is really abundant in winter and it is common for the road to be impassable even in April.

Technical data of the original inclined lift

Implementation of the entire project began on 16 May 2022 and comprehensive testing is scheduled for mid-November 2022. The elevator, including the track, stop walls and exit platforms, will be dismantled. But it will remain on Čierny Vah. At least part of it. Colleagues at the power plant came up with the idea of keeping the cab and part of the trackway and displaying the old elevator as a monument on the grounds of the power plant. All visitors will be able to see it.