The work of around four kilometre tunnel between Howrah Maidan and Esplanade metro stations of the ongoing East West Metro project was completed on Thursday.

Construction of the tunnel ~ Prerna ~ began on 21 April, 2016, and the tunnel boring machine on Thursday reached the Esplanade station.

Another tunnel ~ Rachana~ from Howrah Maidan to Esplanade will be completed soon, a senior KMRC official said.

Engineers and technicians from different countries are working with Indian experts for speedy completion of the works of rest of the tunnel.

Metro will start to operate from Salt Lake Sector V to Phool Bagan, which is part of Phase I of East West Metro, by October this year.

From Sealdah station to Howrah Maidan, metro will start plying by December, 2020. Esplanade will be the busiest metro station by 2020, according to a survey prepared by the East West Metro.

On the way of tunneling, the TBM machine had crossed many heritage buildings and old structures, including Howrah railway yard, Bankim Setu, Howrah station, Brabourne Road flyover, Beth El & Magen David synagogue, St Andrews church on Brabourne Road, Writers Building, Old Telegraph office and Raj Bhawan.

Several dilapidated buildings were encountered and necessary protective measures were taken to safeguard those buildings and the inhabitants, a KMRC official said.

KMRC officials could spend only Rs 900 crore till January 2018, out of the Rs 1,937 crore allotted for 2017-18 fiscal owing to various reasons beyond the control of the Metro Railway.

Completion of the ongoing East West metro project was delayed due to unauthorised encroachment and clearance, Metro Railway official said.

Archaeological Survey of India’s clearance for construction under heritage buildings in the Dalhousie area came late, hile there was also a delay in getting approval for work in Defence-owned land adjoining Esplanade.