Sakhalin island tunnel: from the past to the future

15 monthMarch 2022

The idea of the construction of the tunnel under the Tatar Strait to connect Sakhalin and inland Russia has been afloat for decades. It was discussed back in the end of the XIX century, however, the economic and technical issues did not allow its implementation.

The history of the construction

In 1930s, the USSR authorities revived the idea of the tunnel construction between the inland territory of Russia and island Sakhalin. The geotechnical surveys started before the WWII. The tunnel planned for the narrowest place of the Tatar Strait was meant to be used for cargo transportation and military purposes, to supply the Soviet Army personnel on Sakhalin Island.

Only in 1950, however, the technical conditions for the designing of the railroad from Komsomolsk-na-Amure to the settlement Pobedino on Sakhalin were approved by the Council of Ministers of the USSR. The construction was supposed to have been finished by 1953, and it was planned to have started operating in 1955. But Joseph Stalin’s death disrupted this plan. In accordance with the approved plan the tunnel could have started from the Cape Sredny and have reached the Cape Pogiby. The length of the underwater part could have been 8 km. The tunnel was meant to connect the lands in the narrowest place of the Strait.

Phases of the construction

In the beginning of 50s of the XX century, the enormous amount of the preparation work was performed: the ports were built, the construction of the railroad with the total length of 200 km with the bridges and related infrastructure was started.

«By the time when it was suitable to start the construction, the secret tunnel in Komsomolsk-na-Amure had been already constructed. It was similar to the Sakhalin tunnel by its length and technical characteristics.  During the construction the staff was formed, these specialists were acquainted with the state-of-art technologies of their time. That is why the Sakhalin tunnel was not a big challenge for them», – commented Vladimir Markov, deputy director of the design institute «Lenmetrogiprotrans».

The specialist made a remark that during the construction of the tunnel the prisoners labour had been used. The implementation of the project involved specialists at high level of expertise, well-experienced in construction under difficult conditions.

After Stalin’s death despite significant spent of the funding, which included buying expensive equipment, the construction was suspended, with the shafts not being even turned dormant. The shafts are still left unguarded, anyone may enter. The rock dams and artificial islands are still visible», – commented Vladimir Markov.

A deep or a shallow tunnel?

More than 10 years ago Metrogiprotrans  and Lenmetrogiprotrans were assigned to develop the feasibility study of the tunnel.  It is interesting, that Metrogiprotrans designed the deep tunnel, while Lenmetrogiprotrans – the shallow one. Both suggestions did not meet further development.

Later Lenmetrogiprotrans was tasked with developing the design of the tunneling connection for three different routes: historical,  the Southern and «new».

– «historical» – the version developed in 50s (the shortest);

– «the Southern» and «new» – two new possibilities in locations, where the geological conditions were better and the infrastructure was more developed.  

These three routes also were considered in terms of the deep and shallow tunnel construction each.

The preparation work performed in 50s included:

  • two shafts,
  • two rock dams1.5 km long,
  • construction of two artificial islands.

Shallow tunnels construction reported two techniques: at the site, where the depth of the Strait is less than 4 metres, the dams were created that later could have been used for the construction of the tunnel sections. The diaphragm wall technology was applied for the pits’ walls and the bottom of the pit was reinforced jet-grouting.

At the section, where the depth of the Tatar Strait is more than 4 metres, with the special equipment  the underwater trenches were planned to have been constructed, where the sections of the tunnel were meant to have been immersed and later connected underwater.

The alternate design of the deep tunnel was planned to have been constructed in the following manner:

  • the sections of the tunnel on the shores to be constructed with cut-and-cover method;
  • the western section of the tunnel to be constructed with the blast-and-drill technique;
  • the section under the bed to be constructed with the EPB TBM.

The diameter of the tunnel was established as 11.5 metres, allowing placement of the cargo section into the tunnel cross-section, the emergency sections and also engineering lines. This decision would have allowed to construct the tunnel without the parallel one and without cross-passages (as  it was in first Metrogiprotrans’ design).

Designed measurements of the Sakhalin tunnel (with TBM):

Total length – 8 km
Diameter – 11.5 м
Depth – about 60 metres

The tunnel was planned for the railway transportation. No road section was included into the design. According to the specialist, for more convenience, the tunnel with such diameter might comprise all mentioned and be divided for operating and technical zones.

«Foreign experience shows that the road section is not necessary for such a tunnel. The Eurostar tunnel under the English Channel transfers vehicles on the rail platforms and it works smoothly. There is no economic reasons for construction of the unique tunnel of the large diameter comprising both rail and road lines», – commented Vladimir Markov.

Future of the tunnel

The developed designs have been in archives for more than 10 years. And their perspectives are not clear. However, high-ranking authorities talk about importance of the Far East transportation infrastructure development including Sakhalin Island.  By 2020, the railroads of Sakhalin will have been modernized to match the European standards, with the width of track being 1,520 mm, while the Japanese has 1,067 mm width. For now Sakhalin uses the later. After maintenance work, it will be possible to connect the railroads of Sakhalin with the rest of the country.

The former president of the OAO RZD – the main rail company of the country – announced the construction of the bridge to begin between 2011 and 2013. Perhaps after the construction of the Kerch Strait bridge the Sakhalin project will get priority due to political and social reasons, especially with the economic growth at the Far East.

There is well-organized «bridge» lobby here, although the bridge project has a lot of disadvantages, like unfavourable climate conditions. «The construction of the tunnel, with the current development of the technologies and equipment, is far easier task», – insists Vladimir Markov. «Also it less impacts the environment, according to the ecologists».

Author of the article: Larisa Dubrovskaya

portal “Underground expert”