Singapore Eyes Undersea Tunnels to Link Mainland with Pulau Tekong

A New Link Beneath the Strait

Singapore is exploring the construction of undersea tunnels to establish a direct land connection between its mainland and Pulau Tekong, the outlying island that serves as the primary training ground for military recruits. Prime Minister Lawrence Wong announced the feasibility study on August 23 during the National Day Rally, describing the initiative as part of a broader vision for long-term infrastructure development.

National servicemen currently travel to Tekong exclusively by boat, a journey that the government now seeks to replace with a permanent land route. The tunnel proposal emerged after officials ruled out bridge construction, which would interfere with active shipping lanes that carry substantial commercial traffic through the strait.

"If we can't go over the sea, we will try to go under it," Wong said, framing the tunnel as the most viable solution despite its engineering complexity.

Engineering at Unprecedented Scale

The city-state has built underground road infrastructure before, but never attempted submerged tunnels of the magnitude required to span the distance to Tekong. Wong acknowledged that the project constitutes a significant technical challenge, one that will demand expertise Singapore has yet to deploy domestically.

The tunnels would need to accommodate vehicle traffic while maintaining structural integrity beneath shipping channels and withstanding the marine environment. Success would transform access to Singapore's outer islands, bringing them into closer functional proximity to the urban core and eliminating the logistical constraints of ferry schedules for the thousands of recruits who cycle through Tekong each year.

Decades in the Making

Wong situated the Tekong tunnel within a portfolio of multi-decade infrastructure initiatives. The government is also advancing plans to merge Semakau, Bukom, Pulau Sudong, and several smaller islands into a consolidated Western island intended for industrial use. Land reclamation will connect Sentosa with Pulau Brani, where the National Trades Union Congress is developing a resort district. Off the East Coast, preparatory work for Long Island reclamation is set to begin in late 2026, creating what Wong described as "another new waterfront for future generations."

These projects share a common timeline measured in decades rather than years, requiring sustained political commitment and capital allocation across multiple government terms. Wong emphasized that the current administration is building infrastructure for cohorts not yet born, mirroring the approach of Singapore's founding generation.

Regional Context and Fiscal Commitment

Large-scale undersea tunnel projects remain rare in Southeast Asia, though the region has seen growing investment in cross-strait infrastructure. Malaysia and Indonesia have both studied tunnel and bridge proposals to improve connectivity between islands and peninsular territories, driven by similar constraints around shipping traffic and geographic fragmentation.

Singapore's willingness to pursue such capital-intensive, long-gestation projects reflects both its fiscal capacity and its strategic imperative to maximize usable land. With limited territorial expansion options, the government has consistently turned to reclamation and subterranean development to accommodate economic growth and population density.

The Tekong tunnel study signals that Singapore is extending this logic to its outer islands, treating them not as remote appendages but as integral components of a unified metropolitan system. Whether the engineering and financial realities align with that ambition will determine if the tunnels move from feasibility study to construction timeline.