On 11th of October 1938 in order to strengthen the fortification of Kiev District of Stalin Defence Line Soviet Union (USSR) government decided to build Object 1 - Tunnels under Dnieper River in case of destruction of bridges during a possible military actions. Construction of tunnels under Dnieper river began in spring of 1938. The project provided building of two underground tunnels under the bed of Dnieper river - North and South.

The idea of building of Tunnels under Dnieper Riverbelonged to Joseph Stalin and main responsible official for the construction of tunnels was Nikita Khrushchev. Object 1 was strictly kept secret. The construction of tunnels under Dnieper river was conducted by workers of trust "Hydrostroy" and employed workers who were carefully selected by NKVD. Workers of Object 1 could not quit their job even during Great Patriotic War all employees were exempt from military service.

Update! Caisson of Object 1 in Park Natalka in Kyiv is in the process of transformation to entertainment center and should be finished the first part of 2021.

Initially according to regulations on works for construction of Tunnels under Dnieper River hired about 2500 people.

Head of the construction of tunnels under Dnieper river was a civil engineer Michael Terpigorev. From Moscow were sent deputy chiefs of construction Nikolay Kuznetsov and Mihail Kovalenko, production and technical service chaired by Alexander Denishchenko - all chiefs were the best specialists of Moscow Metro Construction.

Building of Object 1 - Tunnels under Dnieper River was the largest defense construction of third of five-year plan. Since the beginning of construction of tunnels total number of workers, engineers and employees increased up to 10000 people by the end of 1939 and in 1940 - up to 20 000 people worked on a large territory of construction - a circle of radius of 25 km.

Construction of Tunnels under Dnieper River began with the caisson - construction for creating a chamber with no water in water-saturated soil. Admission of water into the working chamber is prevented by injecting compressed air into it. Caisson typically constructed on the surface (17 meters * 52 meters) and by special procedure sinked underground under its own weight.

When the caisson was at depth of 30-40 meters began horizontal construction of tunnel using tunnel boring machine. The tunnel boring machine was non-mechanized. In its working chamber pumped air (up to a pressure of 2-5 atm) which pressed water from aquifers and do not let it to came inside of working chamber. The method is very efficient from an engineering point of view but it is extremely harmful to health of workers because it caused decompression sickness.

On non-mechanized tunnel boring machine there were 36 jack-screws each of them developed a force of up to 300 tons. Jack-screws moved tunnel boring machine to 70 cm then workers mounted cast iron rings of tunnel. Starting from this new ring jack-screws moved tunnel boring machine to another 70 cm and so on.

For the team of ten people was a record to mount one ring for one shift. Construction of Tunnels under Dnieper River was carried out day and night in three shifts. Duration of shift changed depends on pressure in the tunnel - 6 hours at a pressure of 1 atm, 40 minutes - at 4 atm.

Construction of both tunnels were divided into separate independent production units so-called "title" from number 1 to number 14. For construction of tunnels were done al lot of groundwork - river bank stabilization, warehouses, provision of electricity, water supply and communications, construction of road and rail sidings, houses for workers and more.

There was a task to provide two independent stand-alone sources of electrical power to Object 1 - Tunnels under Dnieper River. For this purpose have built a power plant. The second source was circular electric line installed around Kiev with inclusion of all city's power plants.

The design length of South Tunnel under Dnieper river was 6,5 km. It was planned that the trains under Dnieper river will move in two directions and the rails will be possible to close by boards so that it can pass cars or tanks. Construction of South Tunnel under Dnieper river should be completed in 1944 by initial plans.

In February 1941 on tunnel boring machine which was moving towards the left bank of Dnieper river happened a big accident. In the area of quicksands the air from the tunnel under the pressure of 2,8 atm suddenly burst to the surface creating the whirlpool that filled the tunnel with water. Workers had enough time to escape. Tunnel boring machine bent face down on blurred ground.

Head of "Title №4" was fired and in March appointed new one - engineer Isaac Barenboim who is well-established as the head of "Title №5". The tunnel boring machine was renovated in early July 1941 when Germans were on the outskirts of Kiev.

Despite the start of Second World War the construction of Object 1 - Tunnels under Dnieper River continued in July. But at the end of July there was the order to mothball construction. Tunnel boring machine protected by a layer of lubricant and cast-iron tubing flooded, machinery and equipment taken out by trains, remaining equipment covered with soil.

On 6th of August 1944 State Defense Committee of Soviet Union (USSR) adopted a resolution №6326 on the resumption of construction of South Tunnel under Dnieper river but soon at the end of 1949 the construction was stopped as unprofitable. Then in 50s from South Tunnel took out a lot of pipes which were used in the construction of Kiev Subway for stations "Polytechnic Institute" and "Vokzalnaya" (Train Station).

You could visit Ukraine Kiev Sights | Object 1 Stalin Tunnels Under Dnieper River as additional option to Kyiv Tour!