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Calle Isla Graciosa, 1
28703 San Sebastián de los Reyes, Madrid. Spain.


+34 91 782 34 00
Fax: +34 91 562 42 98


OSSA in the world

OSSA has a backlog outside of Spain of 420 M $ in various countries.

Click on each continent to see OSSA’s international presence. Click on the name of the country to get contact details.

OSSA has earned a reputation over the years as an international specialist contractor able to deliver competitively anywhere in the world.

Some of the most relevantinternational projects include:

  • Access works and construction facilities Andesita Project for CODELCO at El Teniente mine (Chile).
  • Construction of civil engineering works, shafts, galleries and tunnels. Section 3 – Line 6. for METRO SANTIAGO, S.A. in Santiago de Chile (Chile).
  • Construction of civil engineering works, shafts, galleries and tunnels. Section 3 – Line 3. for METRO SANTIAGO, S.A. in Santiago de Chile (Chile).
  • Contract to execute air injection tunnels for CODELCO in Chuquicamata, Chile.
  • Contract C824 in the Hong Kong to Shanghai high speed rail line (XRL) for Hong Kong MTR Corporation.
  • Highway tunnel contracts in Greece for GRUPO FERROVIAL.
  • Suhua Improvement C1 Tunnels para CHIEH HSING en Huan Lian (Taiwan).
  • Emergency Tunnel Repair Contract in Panama (Túnel Central Hidroelectrica ESTI) for AES.
  • Hydropower Plant in Costa Rica (Central Hidroeléctrica El Torito) for GAS NATURAL FENOSA.
  • Mining contract in Perú (Tunel Mina Toquepala) for SOUTHERN PERU COPPER.
  • Tunnel construction project in Perú, Túnel del Carmen for INTERSUR.

Our experience working for Energy and Utility companies such as IBERDROLA, ENDESA, GAS NATURAL FENOSA or AES is critical for our continued success in the hydropower sector where we have designed/built tunnels through many varying geological conditions and under all different kinds of contracts (Lump Sum, Target Cost, Unit Price, or Cost Plus).

We have been prequalified to carry out several mining and civil works projects in Chile, Malaysia, Portugal, Brazil, Colombia, Great Britain and the USA.

Our international strategy is a key driver for corporate growth as a leading underground specialist contractor. Our role in Joint Ventures is to provide specialist services and resources (Technical tunnel Engineering, Manpower and Equipment) to our general contracting partners. We also work as Subcontractors for private clients or General Contractors on construction or design/build contracts.