Circumferential dams of the upper reservoir are earth ones, cambered by 1.7 m above maximum level.
The dam 1 is 446 m long. Air dam slope 1 : 1.75, upstream slope 1 : 2.
The dam 2 is 356 m long in the crest. The dam has air slopes adjusted in inclination 1 : 1.35.
The dam 3 has cross profile similar as the dam 1 and its length in the crest is 252 m.

Major parameters of upper reservoir dams (see table)

Inlet work
The whole inlet work consists of several parts. The function of inlet work is to control feeder shutters in a position of the upper reservoir. The separate sites of the inlet work are as follows:: inlet basin, three separate inlets into feeders and the feeders.

Water inlet to electric power plants – feeders
The feeders represent a connecting hydraulic way between the upper and lower reservoir. Water inlet to the electric power plant is solved by three underground pressure feeders of 3.8 m clear profile, which in fluvial plain go over into pressure pipes with concrete encasement of 3.6 m clear profile and fal into spherical distributor.

From the technical and technological point of view the underground feeder part may be split in two parts and namely to inclined sections and horizontal sections. The horizontal parts have parameters that correspond to standard stoles. The inclined feeder parts with 45° inclination differ significantly from the standard underground mining or engineering ones. The inclined sections are tunneled bottom up to the profile of 2.1 x 2.1 m by the ALIMAK climbing platform.

The thickness of feeding pipe varies from 12 to 44 mm.
Each feeder includes two turbines or two pumps. The spherical distributor with internal diameter of 5,600 mm splits water flow by two pipes up to 2,200 mm to two turbines and it is connected to the the pumps of water pumping from the lower reservoir to the upper one through another twoo pipes.

The feeder leads water to two turbines in amount of 2 x 10 m3.s-1 and it fills the upper reservoir in amount of 2 x 20,9 m3.s-1 at pumping operation. There is an underground inclined lift located beside the feeders serving for transport of operation employees of the pumping hydroelectric power plant to the upper reservoir.

Information & Contact:

Research Institute of Water Management,
Nabr. arm. gen. L. Svobodu 5,
811 02 Bratislava,
tel.: 00421 (2) 59343111,
fax: 00421 (2) 54415743