A rock solid foundation Grouting and casting works have caused us to be intensively engaged in the topic of "underwater concrete". Due to our long-time experience with both, reinforced and ordinary concrete we were able to build-up a one-of-a-kind valuable knowledge in our area of expertise. Depending on the intended application, either erosion-resistant Hydrocrete® or other fluid underwater concrete is used. According to the dimensions and conditions of the site the optimal concrete composition is determined. gewatech was able to prove that it is possible to build a crack-free underwater concrete slab with a length of 85 m and a thickness of 1 m. Thanks to thorough preparatory works, the right concrete composition and installation technique, gewatech can guarantee pre-defined seal tightness. Reinforced underwater concrete with a thickness of 1.20 m at a water depth of 34 m. Power current tunnel, Bewag Municipal Works, Berlin Pumped-out, yet not cleaned foundation pit at the Rolandufer, Berlin.