Project Profile: Bangkok MRT Green Line (Sukhumvit Line) Extension

This project profile details the large-scale expansion of Bangkok’s Mass Rapid Transit (MRT) Green Line, a critical infrastructure initiative designed to alleviate urban congestion and enhance public transport connectivity across the metropolitan area. The project involved two major elevated extensions—a northern route from Mo Chit to Khu Khot and a southern route from Bearing to Samutprakarn—significantly increasing the line’s capacity and operational footprint.

Project Fact Sheet

Technical Specifications

The Green Line extensions are fully elevated viaduct structures, a design choice made to minimize disruption to Bangkok’s dense urban landscape and existing traffic arteries. The project’s infrastructure is powered by a 750V DC third-rail electrification system, provided by Siemens for the southern extension, ensuring consistent and reliable power delivery to the rolling stock. Two major depots were constructed to support the expanded operations: one at Bang Pu for the southern line and a new main depot with an integrated Operation Control Centre (OCC) at Khu Khot for the northern line.

To meet increased passenger demand, the project introduced a new fleet of four-car metro trains. These units are designed for high-capacity urban transit, capable of accommodating over 1,500 passengers per train and operating at speeds up to 80 km/h. The track work, managed by a consortium including Ch. Karnchang and Alstom, was engineered for durability and high-frequency service, supporting the line’s function as a primary commuter corridor.

Key Takeaways

• Enhanced Urban Connectivity: The addition of 25 new stations across 28.6 km of track has integrated previously underserved residential and commercial zones into Bangkok’s rapid transit network, drastically reducing commute times.
• Successful Public-Private Collaboration: The project demonstrates a successful financing and execution model, combining public funding from the Bangkok Metropolitan Administration (BMA) with the operational expertise of a private entity (BTSC) and specialized engineering from international contractors.
• Scalable Infrastructure Model: The project’s phased approach, technical standards (elevated structures, 750V DC power), and depot strategy provide a robust framework for future urban rail expansions in Bangkok and other major Southeast Asian cities.

Frequently Asked Questions (FAQ)

When did the Bangkok Green Line extension open?

The Bangkok Green Line extension was opened in two phases. The southern extension from Bearing to Samutprakarn became fully operational in December 2018, and the northern extension from Mo Chit to Khu Khot was completed and opened in December 2020.

Who built the Bangkok Green Line extension?

The construction was a collaborative effort involving several key organizations. The project was primarily funded by the Bangkok Metropolitan Administration (BMA) and is operated by the Bangkok Mass Transit System Public Company (BTSC). Major construction and systems contracts were awarded to companies including Ch. Karnchang Public Company for track work, with Alstom providing power collection systems and Siemens supplying the rail electrification infrastructure.