Santiago Metro Line 9, Santiago, Chile

Santiago Metro Line 9 is the network’s next north-south trunk: 27 km and 19 stations from central Santiago south to Puente Alto, with six new interchanges. On Oct. 20, 2026, Australian rail contractor Martinus said it had won the contract to design and build the line’s track and overhead electrification, plus a separate 20-year maintenance deal.

That award fills in one of the last big systems packages. Metro de Santiago is buying the line in pieces, and most of the delivery team so far is foreign.

Project Scope

The route passes through eight communes: Recoleta, Santiago, San Miguel, San Joaquín, La Granja, San Ramón, La Pintana and Puente Alto. It’s split into three sections. Section 1 has 10 stations between the existing Bío Bío station on Line 6 and a future Plaza La Pintana station. Section 2 adds four stations from Puente Cal y Canto to a terminus at Avenida Santa Rosa and Avenida Ñuble. Section 3 carries five stations from Plaza de La Pintana to Plaza de Puente Alto by way of Bajos de Mena. A maintenance and storage depot completes the scope.

Environmental approval for the first two sections came in May 2025. Preliminary works began that month, and excavation started that September.

Three contracts stand out. Spain’s OHLA won civil works for shafts, galleries and tunnels on subsections 1C and 1D in July 2026, a €144.3 million package covering 7.6 km of underground work and the company’s largest contract with the Santiago Metro. Colas Rail took a contract worth about €104 million in June for the electrical systems: a distribution center, eight rectifier substations, 39 lighting and power units and the SCADA system for power and traction, with 20 years of maintenance. Martinus now has track and catenary. It says the job adds about 300 jobs in Chile and doubles its local workforce to 600.

Colas puts total investment at about €2.5 billion, and Railway Gazette reports US$2.7 billion. The first section is due to enter service in 2030.

Why It Matters

Line 9 gives Santiago’s southern half a second trunk line, with connections to seven existing lines. Puente Alto, Chile’s most populous commune, currently reaches the metro through Line 4. Metro expects about 2 million residents to benefit.

The procurement model deserves attention. Metro de Santiago is splitting civils, power and track into separate packages, each tied to long maintenance terms, and that leaves interface risk with the owner. Martinus has worked in Chile since 2021, mostly on maintenance and project delivery for state railway EFE, so this is its biggest metro systems role there.

The stretch to watch is Section 3. Its environmental study was still being prepared in mid-2025, and the Bajos de Mena extension is the piece most exposed to slipping past the 2030 opening of the first section.

Project Team & Details