Jakarta MRT Completes First Tunnel Between Harmoni and Sawah Besar
Key Takeaways
|
JAKARTA, Investortrust.id — PT MRT Jakarta has completed the first tunnel connecting Harmoni and Sawah Besar stations on Sept. 1, 2025, marking a major milestone in the development of Phase 2A of the North–South line.
The tunnel stretches 390 meters and was built under contract package CP202. It links Bundaran HI station with Sawah Besar station. The company announced the progress in an official statement, saying, “This tunnel section is part of Phase 2A construction, and with its completion, Bundaran HI and Sawah Besar stations are now connected.”
Construction of the tunnel took four months, from May 9 to September 2025, using Tunnel Boring Machine (TBM) 1. The machine will next continue drilling 790 meters toward Mangga Besar station at a depth of 28 meters, a project targeted for completion in June 2026.
MRT Jakarta said the design of the tunnel and the Sawah Besar and Mangga Besar stations differs from Phase 1 and other packages in Phase 2A. Unlike the parallel layouts of earlier stations, these two stations will be built on multiple levels, a design chosen because Sawah Besar sits beneath Jalan Gajah Mada and Mangga Besar beneath Jalan Hayam Wuruk.
Analyze transport and infrastructure stocks quickly and easily with InvestingPro — enjoy an exclusive discount for Investortrust readers. Click here to access the offer.
From Vision to Operation
The idea of a mass rapid transit system in Jakarta dates back to 1985, when the National Technology Agency studied rail-based solutions for the capital’s growing congestion. The government declared the project a national priority in 2006, and construction began in 2013 with financing support from the Japan International Cooperation Agency (JICA).
Phase 1 of the North–South line, running 15.7 kilometers from Lebak Bulus to Bundaran HI, was inaugurated by President Joko Widodo on March 24, 2019. The line included 13 stations and cost roughly Rp 16 trillion, or about $1 billion, funded mainly by soft loans from JICA. The project marked Indonesia’s first modern underground and elevated mass transit system.
Future Expansion
Phase 2A extends the line 5.8 kilometers north to Kota with seven underground stations: Thamrin, Monas, Harmoni, Sawah Besar, Mangga Besar, Glodok, and Kota. The investment for this phase is estimated at Rp 25.3 trillion, equal to $1.5 billion, with financing again supported by Japanese loans. Completion is projected between 2027 and 2029 depending on construction progress.
Beyond Phase 2, the government has also mapped out plans for an East–West line, with tenders worth more than $3 billion already being prepared. Together, the expanded network is intended to form the backbone of Jakarta’s public transport system and to cut reliance on private vehicles in one of the world’s most congested capitals.
Significance
Completion of the Harmoni–Sawah Besar tunnel confirms progress in Phase 2A and signals that Jakarta’s underground construction is advancing despite complex conditions. The multi-level design of the new stations reflects the engineering challenges of building beneath Jakarta’s dense urban corridors.
Once finished, Phase 2A will extend the line to Kota, integrating with other transport modes and reinforcing transit-oriented development in Jakarta’s historic downtown. The expansion is expected to significantly boost ridership and strengthen Jakarta’s long-term infrastructure resilience.