Terratec-made Tunnel Boring Machine (TBM) Godavari-4 finished boring the 1.5km long tunnel under the Mithi River.  Godavari-4 had started boring on August 21, 2019. The TBM bored from BKC to Dharavi.

Godavari-4 bored 15-20 metres below the river bed. The soil under the river is said to be uneven which was studied carefully before the boring.

This is an important milestone for the MMRC. Congratulations.

https://www.mid-day.com/articles/colaba-bandra-seepz-metro-3-corridor-mmrc-completes-tunneling-beneath-mithi-river/22944265