The realignment led to many other issues and delays. Some of the biggest issues were the H-piles under Esplanade metro station and the Bowbazar mishap. As per the 1971 master plan, the East-West Corridor was supposed to pass under Central metro station, so the square foundational beams in Esplanade were not removed. Since the Tunnel Boring Machines (TBMs) cannot cut through steel, another small tunnel was dug using New Austrian tunnelling method (NATM) and the H-piles were cut manually. This extended the tunneling process by one and a half months. In September 2019, during the construction of the eastbound tunnel (from Esplanade to Sealdah), a TBM hit an aquifer under Bowbazar, causing a major collapse in the area, delaying work in that section for several months. Around 80 houses were damaged and many buildings were declared unsafe, affecting more than 600 people. Later subsidence in the area was checked using grouting.