The whole line of Tokai-Hokuriku Expressway has been open to the public since its completion of the route between Hidakiyomi IC and Sirakawago IC in July 2008. As a result, the Hokuriku and Tokai areas have been connected directly, which will greatly contribute to the development of industries, economies and cultures in the areas.
Hida Tunnel (length: 10.7 km) with the maximum overburden of 1040 m is the second longest road tunnel in Japan. TBM was adopted in tunnel excavation. The diameter of the TBM was 12.84 m, which was one of the largest in the world. Weak geological features and a large amount of spring water made construction of the tunnel very difficult, but no fatal accident occurred.
This Hida Tunnel construction greatly contributes to the development of mountain tunnel technology in the future.