Lake Sevan - Intervention

Intervention

In 1910 Soukias Manasserian, one of the civil engineers behind the interventions that caused the Aral Sea disaster, published a study Evaporating billions and stagnation of the Russian Capital, which suggested the lowering of the lake's surface to 45 metres and the use of the water for irrigation and hydroelectricity.

In Joseph Stalin's era the plan was slightly modified: the water level would be reduced by 55 metres (5 metres more than suggested by Manasserian), the perimeter would shrink to 80 km and the volume to only 5 km³. Nut and oak trees would be planted on newly acquired land, and introducing some trout species into the remainder of the lake would increase fishery production tenfold.

The Armenian Supreme Soviet approved the plan without consulting the local people, and major work started in 1933. The river bed of the Hrazdan was deepened, and construction of a tunnel 40 metres below the original water level was begun. The work was delayed due to World War II and was only finished in 1949. The water level then began to fall by more than one metre per year.

As a result of these activities, the level of the lake fell by 19.01m, from its original of 1,915.9m. The lake is now 1,896.86 meters high; the volume has declined from 58.5 billion cubic meters to about 34.0, and the surface area has shrunk from 1,416.2 km2 to 1,238.1 km2.

An ecological disaster like in the Aral Sea was avoided when the Stalinist era ended in 1956 and the project and its consequences were reviewed thoroughly. As there were difficulties with planting oaks and nut trees, and with fishery, the Sevan Committee was established with the mission "to raise the level as much as possible". Hydro-electric power stations on the Hrazdan would be replaced with thermal power stations. In 1962 the water level stabilized at 18 metres below the original level, but two years later the lake started to "bloom" due to eutrophic algae.

In 1981, a 49.3 km tunnel was constructed, diverting water from the Arpa river (from a reservoir near Kechut) to the lake near Artsvanist. The water level in the lake rose only 1.5 metres, so another 21.7 km tunnel was begun from Vorotan River (further south from Kechut). Eighteen kilometers of this tunnel were completed before the collapse of the Soviet Union, but in 1988 Azerbaijan imposed an economic blockade on Armenia due to the Nagorno-Karabakh conflict, and the work had to be stopped.

The Armenian government completed the Vorotan tunnel in 2004, but water has not yet begun to flow into the lake. The level stabilized at 20 metres below the original, and the lake's area is now 940 km².

On March 2, 2012 the chairman of the presidential committee on Lake Sevan issues stated that in line with the laws adopted since 2001, the water level of the lake had risen by 380 cm and the lake stands today at 1900.19m high.