Underwater Tunnels in the Faroe Islands

Project Background

In May 2014, Norconsult signed the contract for the design of the Sandoy Tunnel and the 11.2-kilometer-long Eysturoy Tunnel.

Prior to this, Norconsult’s advisors had successfully designed and overseen two other underwater tunnels in the Faroe Islands: the Vaga Tunnel (2002) and the Nordoy Tunnel (2006).

The Assignment

The projects were initiated to improve connectivity in the Faroe Islands. The new Sandoy Tunnel, a key component, was designed to facilitate ferry-free travel for the residents of Sandoy to Tórshavn, the capital.

With a minimum of 50 meters of solid rock above the tunnel crown, the design addresses both safety and durability requirements in a challenging underwater environment.

The Solution

The Sandoy Tunnel is 10.8 kilometers long and reaches a maximum depth of 147 meters below the fjord, running from Gamlarætt on Streymoy to Traðardalur on Sandoy.

The tunnel’s cross-sectional area is 73 square meters and includes five pumping stations, nine technical rooms, and 86 emergency kiosks. Norconsult employed advanced 3D/BIM methods—transitioning to drawing-less BIM design from 2015 to 2023—for all aspects of the project, ensuring precision and efficiency throughout the design and construction process.

The combined project costs for the Sandoy and Eysturoy Tunnels amounted to NOK 4.1 billion, marking it as a significant undertaking for an island community of approximately 50,000 inhabitants.

The Result

The Sandoy Tunnel was officially opened on Thursday, December 21, 2023. Along with the Eysturoy Tunnel, these projects reduce travel times to Tórshavn so that large parts of the Faroe Islands are now within a one-hour journey from the capital.

Norconsult’s pioneering work in underwater tunnel design is further underscored by their leadership on projects such as the world’s longest underwater tunnel for regular traffic, Ryfast, and the ongoing construction of Rogfast, which will be the world’s longest underwater tunnel once completed.