Why in news?  A 7-km undersea tunnel will be constructed for the bullet train project in a bid to save about 12 hectares of mangrove forests in Maharashtra’s Thane creek.

Highlights

• Constructing the tunnel in the Thane creek will be a massive challenge as it will involve two tunnel boring machines (TBMs) that will meet halfway under the sea to join two parts of the tunnel by a process called docking.
• The construction cost of the Mumbai-Ahmedabad High Speed Rail Corridor project’s from Bandra Kurla Complex Station to Shilphata, rose from 100 crore to Rs.10,000 crore.

About Thane Creek

• It is an inlet in the shoreline of the Arabian Sea that isolates the city of Mumbai (Bombay) from the Konkan region of the Indian mainland.
• Creek was formed due to a seismic fault lying below it which runs from Uran to Thane.
• The area has been designated as a protected Ramsar site since 2022 and region is recognized as Important Bird Area by the Bombay Natural History Society.
• The Maharashtra Government has declared the area along the western bank of the Thane Creek as the “Thane Creek Flamingo Sanctuary“.