Surat Metro Underground Section - 6.47 km Tunnel and 6 Stations

The 6.47 km underground section runs through the oldest and most congested part of Surat, from near Kapodra to Gandhi Baug. Surface-level or elevated construction was not feasible here due to narrow roads, dense building clusters, heritage structures near Maskati Hospital, and the existing Surat Railway Station infrastructure. Going underground avoids demolishing hundreds of properties and disrupting railway operations. The DMRC-prepared Detailed Project Report (DPR) identified this stretch as the only corridor segment requiring below-ground alignment based on land acquisition constraints and urban density analysis.

Exact depth figures for each station have not been publicly released by GMRC as of September 2026. Typical cut-and-cover metro stations in Indian cities sit 12 to 18 metres below street level, with platforms at the lowest level and concourse halls above. The underground section uses 750V DC third rail electrification, same as the elevated sections, so the tunnel dimensions follow standard gauge (1,435 mm) clearance requirements. Forced ventilation systems and fire suppression equipment are installed throughout the tunnel and at all six underground stations to manage air quality and emergency evacuation.

TBM stands for Tunnel Boring Machine, a large cylindrical machine that excavates circular tunnels through soil and rock while simultaneously installing precast concrete lining segments behind it. GMRC deployed three TBMs for the Surat Metro underground section: Amrit, Narmada, and Tapi. TBM Amrit achieved breakthrough at Chowk Bazar Station in August 2025, the first major tunneling milestone. Narmada and Tapi completed their breakthroughs subsequently. All three machines are named after culturally significant references: Amrit Mahotsav (India's 75th independence anniversary), the Narmada River, and the Tapi River that flows through Surat.

Yes. Surat Railway Station is one of the six underground metro stations on Corridor 1 (Red Line). It provides a direct connection to Western Railway mainline services, including trains to Mumbai (about 4 hours by Vande Bharat), Ahmedabad, Vadodara, and long-distance routes to Delhi and Kolkata. The metro station is positioned underground to avoid interfering with the existing railway yard and station building. Passengers arriving by train can walk to the metro platform without crossing surface roads, making it the most significant intermodal node on the Surat Metro network.

No. The Green Line (Corridor 2) is entirely elevated across its full 18.74 km length from Bhesan to Saroli, with all 18 stations built on elevated viaducts. Only the Red Line (Corridor 1) has an underground section. The Red Line runs 21.61 km from Sarthana to Dream City, of which 15.14 km is elevated and 6.47 km is underground. The underground portion covers 6 of the Red Line's 21 stations. The remaining 14 Red Line stations and all 18 Green Line stations are elevated, giving the network a total of 33.88 km elevated and 6.47 km underground alignment.