Preparation works for the construction of the excavation pit are progressing on site. A diaphragm wall construction will go down to ca. 31 metres below ground in order to deal with the high water levels and enable construction of the retaining walls for the basement. Construction started with the installation of concrete guide walls to set out the position of the diaphragm walls around the site measuring 100 m x 100 m. Currently four drills are on site to carry out the drilling of ca. 6.400 metres length. Two diaphragm wall grabs are preparing the diaphragm wall in which the retaining walls will be inserted as sheet piles. Explosive ordnance surveys were carried out in advance of construction as this part of the historic city centre of Leipzig had been severely bombed in 1943.