Two workers, dressed in traditional work clothes, are pulling wood out of the Alluvial Canal.
Two workers, dressed in traditional work clothes, are pulling wood out of the Alluvial Canal.

Project description of the project partners

The section of the Schwarzenberg Alluvial Canal that has been repaired lies between the Vltava and Danube watersheds and the Austrian settlement of Unterurasch. This section encompasses parts of the Schwarzenberg Alluvial Canal, as well as the Ottenschlager Bach (also known as Reithbach or Otovský potok in Czech) and Zwettlbach (known as Světlá in Czech). Each of these sections has unique characteristics, and they were constructed differently from one another. Likewise, the repair work performed on each section was tailored to address its specific needs.

The repaired section of the Schwarzenberg Alluvial Canal spans 760 meters from the former settlement of Rosenhügel (Růžový Vrch / U Korandy) at the watershed to the point where it meets the Ottenschlager Bach. This stretch of the channel is notable for its low gradient and water flow. Additionally, the canal road traverses a non-load-bearing peat subsoil, and numerous springs are present in the area around the stream.

The stone bank walls in this section are relatively short (measuring between 0.6 and 1.0 meters), and in areas where the subsoil was unsuitable, they were founded on wooden grates constructed across the entire width of the canal. After the repair, it is apparent that the ground has been paved with stones and secured with tree trunks in alternating fashion. It is also interesting to note the alternating styles of stonework in this section. Typical sections feature horizontally laid stones and continuous horizontal joints, while other areas use flat stones that are vertically laid side by side, extending the full height of the wall fortification.

The Schwarzenberg Alluvial Canal eventually flows into the Ottenschlager Bach. This section is approximately 1.68 km long (stretching from kilometers 0.600 to 2.280) and is characterized by a steeper longitudinal gradient and higher water discharges. Despite this, there are still areas with non-bearing rock that remain waterlogged. The stone wall reinforcement in this section is higher than in the previous segment, measuring between 0.8 and 1.2 meters. Stone paving is the predominant ground reinforcement method, although in areas with non-load-bearing subsoil, the stone walls were founded on wooden beams reinforced with transverse wooden sleepers.

During the repair work, significant beaver activity was noted in the original canal road. The European beaver had constructed several dams that impeded the flow of water, necessitating their removal with the approval of the nature conservation authorities. Following the completion of the repairs, the beaver has resumed its efforts to reclaim its original habitat and has been observed attempting to re-inhabit the rehabilitated canal.

The Ottenschlager Bach section from river kilometers 0.000 to 0.600 is located in a closed valley with a steep longitudinal gradient, and it is arguably one of the most picturesque segments in the area. The bank reinforcement in this section consists of hewn stone vertical walls that are approximately 1.5 meters in height. The bottom of the channel consists of stone cobbles and a stone floor, with stone paving and wooden cross-sills used for reinforcement. Because of the difficult terrain, only minor modifications were made to the upper section of this area, on the right side of the bank walls.

The Ottenschlager Bach flows into the Zwettlbach, which is a relatively large watercourse that experiences frequent flooding. As a result, the fortification of this section of the Schwarzenberg Alluvial Canal was historically designed to be the most resilient. The bank reinforcement here is comprised of stone walls that are approximately 1.0 to 2.0 meters in height and up to 1.5 meters wide in certain areas. The bed of the channel is paved in sections with a steeper longitudinal slope and stone paving. Additionally, there are unpaved sections that are connected with fixed slides to stabilize the ground. 

As part of the rehabilitation project for the Schwarzenberg Alluvial Canal, a new forest path named "K Opona" was constructed, spanning a length of 1.352 kilometers. The path begins at the former settlement of Rosenhügel (Růžový vrch / U Korandy) and follows the course of the Schwarzenberg Alluvial Canal and the Ottenschlager Bach Canal, ultimately leading to the location where the Iron Curtain once stood during the previous regime. The primary purpose of the forest path is to provide access to the technical monument, as well as for future maintenance of the Schwarzenberg Alluvial Canal and transportation of forestry equipment.


Contact information:

Lesy České republiky, s. p.
Přemyslova 1106/19, Nový Hradec Králové
Hradec Králové 500 08
Czech Republic

Tel: (+420) 956 999 111 | Fax: (+420) 495 262 391 | E-mail: lesycr(at) | Website: | Lesy České republiky, s. p. ( | Schwarzenberský plavební kanál | Lesy České republiky, s. p. (