While the construction of the suburban line, the upper Wientallinie and the waistline brought only minor difficulties, the lower Wientallinie prepared due to complications in connection with the regulation and partial doming of the Wienflusses much larger problems. So the river often had to be completely relocated to make room for both objects. In some places entire groups of houses were demolished. The construction was the most difficult at those points where the foundations of the city railway walls often reached six to seven meters below the foundations of the old neighboring houses. In addition, the flood events that occurred at that time caused widespread destruction of the buildings in the critical state of foundation and led to construction interruptions. In particular, this was true for the so-called century flood in July 1897.