The Central Railway (CR) crossed a major milestone with its mega block yesterday - the very first stretches of the much-awaited fifth and sixth lines are finally in place.

On Sunday, in a joint effort by CR and the Mumbai Railway Vikas Corporation (MRVC), the newly-built Kalyan-bound slow line was linked to the older line. This means that from this morning, slow suburban trains to Kalyan will use the 1.2-km stretch of the newly constructed line. On October 14, the CST-bound Up corridor (Line 6) will be connected similarly.

"This is a major achievement. It had been in the works for such a long time and, on Sunday, finally we connected the old lines with the new. The corridor begins from Kalwa carshed till the Mumbra tunnel. Next week, we shall take up the Up line corridor. Passengers may not feel the difference, but we are building a new corridor kilometre by kilometre, as we create space, cut and connect the old and new lines," a, MRVC official said.

MRVC spokesperson Sanjay Singh confirmed the development. The fifth and sixth lines are expected to be complete by mid-2019. The project, which was sanctioned in 2008, is a part of the Mumbai Urban Transport Project (MUTP 2B) and is crucial for CR, as it will be a key factor in segregating the outstation and local train corridors, and thus improve speed and frequency.

Currently there are six railway lines between Kalyan and Diva, and Lokmanya Tilak Terminus (LTT) and Thane. However, between Thane and Diva, there are only four lines, resulting in a bottleneck for outstation trains. Once this project is complete, there will be complete segregation. The project's original deadline was December 2015, which was later revised to December 2017, then to March 2019, and is now mid-2019.

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