Inspection gates for Bleiloch and Hohenwarte dams (Bleiloch and Hohenwarte, Thuringia)

Various refurbishment activities are required for the medium-term continuous operation of the power station at the Bleiloch and Hohenwarte dams.  For this purpose, it is necessary to drain the turbine inlets by means of new inspection gates.

The dams of Bleiloch and Hohenwarte are located on the Obere Saale river in the free state of Thuringia and are integrated in the "Saale-Kaskade" power stations. The dam wall of Bleiloch dam has a height of 65 m; the dam wall of Hohenwarte is 75 m high.

The inspection gates are used for sealing the inlet structures on Bleichloch and Hohenwarte dams. They consist of a series of gate segments of different types. These shut off the inlet against the concrete geometry over its complete height. The medium sealing line on both inlet structures is 12 m. Starting from the sill of the inlet structures, the inspection gates extend over the maximum water level mark of the relevant dam.

One series of gates generally consists of two types of submerged gate segments (floatable) and surface gate segments (not floatable). Each series is composed individually from the individual gate segment types for the relevant place of use.

The submerged gate segments are fitted with a certain number of floating and taring cells, as well as permanently flooded cells on their bottoms. The surface gate segments are provided for water transport and are floatable for this purpose. For lowering the gate segments in the inspection gate series, two guide carriages are required on each segment. These are coupled near the water surface after the gate segments have been floated. By ballasting the taring cells, these units (gate segment with two coupled guide carriages) are loaded to a lowering weight of between approx. 1.5 t to 2.0 t max. and lowered by means of a rope winch.

The non-floatable surface gate segments are transported from the unloading point to the dam wall by means of pontoons. The inspection gates are set down by means of a double rope winch specifically designed for this task.

Scope of planning:
- Design planning

Project planning
Structural planning
Technical equipment
Construction logistics