Dams

In 2003, a 1.5-mile-long sewage pipe had to be lowered in a controlled manner in the Rursee from Rurberg to Woffelsbach. In advance, the route was measured at the bottom of the Rursee and checked by divers.

In particular, the subject of the investigation was the local boat docks, as these were anchored to the ground due to the fluctuating water levels. The anchor points were not allowed to come into contact with the route to be laid in any way. For this purpose, these have been partly relocated in the interest of the boat landing stage. 

The route was connected on the water and lowered in a controlled manner after precise measurements. All work ran without interruptions in compliance with the deadlines, despite the formation of ice on the Rursee.

Revision checks of the bottom outlets at the Hennetalsperre are to be carried out at regular intervals. With this year's safety check, the company Aqua-Nautik GmbH was commissioned with the necessary diving work. In order to inspect and, if necessary, repair the 5 ft steel pipes, which are located on the left and right on the slope of the dam, the basket rakes had to be removed from the inlets.

They prevent flotsam from getting into the bottom outlets, which can damage the power plant. The 4.5-ton basket rakes were lifted from a depth of 150 ft and handed over to the customer for inspection. Further dives included cleaning the contact area, as well as draining and inserting the inspection seal. Since one of the two bottom outlets must always be in operation for safety reasons, the two lines were inspected one after the other. Another task was to install two level measuring tubes. For this purpose, the accessible tunnel was drilled through on the ceiling side.

The task was to completely prevent the ingress of water during assembly. This was done by mutual seals in the interior and exterior of the tunnel. After making the opening, the level measuring tubes including the protective cover were also installed by the divers from Aqua-Nautik.