Metropolitan rail networks in Southeast Asia are on track to expand 20% by the end of next year, a Nikkei analysis shows, the growth fueled by the need to ease congestion and reduce automobile emissions.

Nikkei examined commuter rail in capital regions and major cities across Thailand, Vietnam, the Philippines, Malaysia and Indonesia. The combined length of rail lines in those places is projected to reach 1,356 kilometers by the end of 2024 from 1,147 km as of January 2023.

In Thailand, the Yellow Line connecting the outskirts of Bangkok to neighboring Samut Prakan province began operations this month. The elevated monorail spans 23 stations over 30 km.

During the trial run in June, the Yellow Line drew about 680,000 passengers in just over two weeks. One test rider was Prime Minister Prayuth Chan-ocha, who described the experience as “comfortable” and urged citizens to use the new link.

The Yellow Line is operated by Eastern Bangkok Monorail, which is a joint venture between BTS Group Holdings — which runs Bangkok’s elevated-rail authority BTS — and a group of investors including Sino-Thai Engineering & Construction.

Thailand has been expanding its metro rail network since BTS began service in 1999. Including subways, the rail lines span more than 200 km as of this year, a coverage fast approaching that of Southeast Asia’s leading metro rail countries Malaysia and Indonesia.

Countries that were late in developing urban rail networks are either opening or planning new lines. In Vietnam, Ho Chi Minh City’s first metro line opens next year, starting with 14 stations over 20 km. Hanoi already has a 13 km subway system, meaning Vietnam’s metro lines will total 33 km by 2024.

In the Philippines, the Metro Rail Transit network is expanding as well. In late June, local conglomerate San Miguel said it has raised 100 billion pesos ($1.79 billion) for the construction of Line 7 connecting the Manila metropolitan area with outer-ring communities.

“MRT-7 will generate countless jobs, boost local economies and create more opportunities for so many Filipinos,” San Miguel President and CEO Ramon Ang said in a statement, referring to Line 7.

Southeast Asia’s urban population is growing along with the region’s economy, bringing widespread traffic jams on city streets and air pollution from vehicle exhaust. Expanding metro networks is a challenge shared by these countries as they seek to shorten commute times and reduce the environmental costs.

Manila’s main roads are constantly choked by cars and motorcycles. In 2017, prior to the pandemic, traffic congestion cost the economy 3.5 billion pesos a day. Increasing rail traffic is expected to reduce emissions from diesel-powered jeepney buses.

Japanese and European rail infrastructure companies have taken the lead in landing orders from Southeast Asia. Tokyo alone boasts over 300 km of subway lines, and Japan’s public and private sectors plan to export years of construction and operational know-how to Southeast Asia, viewed as a key market.

Tokyo-based builder Shimizu won a contract in Indonesia last year to build part of a rail line due to open in 2029. The project includes three subway stations. The bid was submitted through a joint venture with Adhi Karya, a local state-owned construction firm.

French rail supplier Alstom last month unveiled new train cars that will serve Singapore’s north-south and east-west lines. Deliveries have started with 16 sets of trains, with a total of 106 sets to be delivered by the end of 2026.

The new trains replace the fleet that has served the two lines for over three decades. The old cars were supplied by a consortium led by Japan’s Kawasaki Heavy Industries.

The new trains, which come at a cost of $1.16 billion, are said to offer more space and accommodate more riders, including those in wheelchairs.

Chinese enterprises have had limited success with overseas rail markets in Asia. But Chinese interests led the construction of the high-speed railway connecting Laos with China’s Yunnan province, which opened in December 2021. China also spearheaded Indonesia’s high-speed rail line, due to begin service as early as this year.

China is expected to wield that track record to compete with Japanese and European suppliers in the region’s metro rail projects.

Many Southeast Asian countries practice a type of balanced diplomacy that maintains favorable ties between the Eastern and Western camps. Rail networks in Southeast Asia usually do not adopt uniform nationwide systems, meaning trains would operate under different standards depending on the line.

In Bangkok, the Red Line adopts train cars made by Japan’s Hitachi while the Yellow Line decided to bring in rolling stock manufactured by China’s CRRC, one of the world’s largest suppliers.

Japan possesses strength in developing housing and commercial facilities as package deals with rail lines. Nishi-Nippon Railroad formed a JV with Philippine real estate developer Axeia Group to build housing that recalls the cityscape of Fukuoka, the Japanese city that is home to Nishi-Nippon’s headquarters.

Japan’s Nomura Real Estate Development has teamed with a group company of Philippine conglomerate GT Capital Holdings to engage in construction projects in Manila through a JV.

But because many rail projects in Southeast Asia are being approved in cities that are already highly developed, few provide opportunities for extra real estate projects.

“The reality is that there is not much capacity to secure new land along rail lines,” said Junichiro Haseba, executive vice president of consultancy SBCS.