We are an international construction company
focused on the most technical construction challenges.

Dillingham Construction International Inc. (DCII), is one of the preeminent construction and engineering firms in the world, with an unparalleled commitment to technical excellence. Based in Ponca City, Oklahoma USA, we specialize in building complex structures and installing sophisticated computerized systems. Our companies provide general construction, design/build, construction management, maintenance, emergency response services, and Build-Operate-Transfer financing for commercial, industrial, heavy civil and marine clients throughout the world.

  • Golden Gate Bridge Seismic Retrofit and Deck ReplacementGolden Gate Bridge Seismic Retrofit and Deck Replacement

    The concrete was replaced with two preformed road sections laid on the exposed floor beams of the bridge structure and the road was widened by 24 inches. The replacement orthotropic surface is 40 percent lighter than the old concrete, and the steel supports of the new structure form the roadway itself. Each of the more than 750 20-ton highway panels and 325 sidewalk panels was individually designed for its particular location.

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  • Azmir MotorwayIzmir-Aydın Motorway and Izmir Ring Road

    Located in the Aegean region of Turkey and part of the Trans-European Road Network, the Izmir Ring Road Motorway project consists of the 53 km Ring Road and the 96 km Izmir-Aydın Motorway. This $1.06 billion project includes three lanes in each direction, secondary roads, junctions, and directional arms which total 333 km of road construction.

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  • Manapouri Second Tailrace TunnelManapouri Second Tailrace Tunnel

    Located in New Zealand, the Second Tailrace Tunnel was constructed to improve the efficiency of the Manapouri Power Station. This $212 million project enabled the generation of an additional 640 GWh a year without using more water – enough electricity to power about 64,000 homes for a year.

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The Second Manapouri Tailrace Tunnel

Learn more about the construction of this engineering marvel.