The River Emscher was to get back its blue shimmer. That is why the river, which sewage and mine water from the surrounding coal mines have contaminated for well on 100 years, is to be renaturized. The clean-up concept, that started in the 1990s, is made up of the river's entire course (85 kilometers long) from Holzwickede to its confluence with the River Rhine at Dinslaken – an area of just over 40 million sq. meters. The core element is the 70-kilometer-long, underground Emscher Sewer. Its directs sewage water to the Bottrop and Dinslaken treatment plants.

A Herrenknecht VSM9000 has sunk a 23-meter-deep start shaft for sewer tunnelling work – an important step, in fact, for renaturizing the River Emscher. For the first time in Germany Herrenknecht's VSM technology was able to fully demonstrate its benefits over the conventional form of shaft construction. Thanks to parallel sinking and excavating, the shaft was finished in just 17 working days – with very little noise produced.

Next to the River Seseke in Lünen, a Herrenknecht EPB Shield excavated a 930-meter-long sewer by pipe jacking for the Emscher renaturizing program.