Levon Vardanyan, Director of «Armenian State Hydrometeorological and Monitoring Service» State Non-Commercial Organization
Recently a number of news websites have published articles about the changes in Lake Sevan level, magnitude of lake balance components, forecasts about the lake level, which are not substantiated.
The system observing water outlets from Lake Sevan and inflows through Arpa-Sevan tunnel is equipped with up-to-date equipment; consequently, there is no need for theoretical calculations and presentation of observation figures, as the factual value of these components are available.
Below is the change of the lake level for 2002-2014:
In 2002- 2004 the hydrometeorological conditions were favourable for the increase in the lake level: 2007 and 2010 were also favourable for the increase in the lake level, as these two years were favourable from hydrological viewpoint.
2008, 2012, 2013 and 2014 experienced lack of water, 2012 and 2014 should be outlined, as the most lack of water was recorded in these very years, resulted with large water outlets from the lake and negative shift in the lake level.
Daily average volume of 1.4 million cum let out in irrigation seasons is a completely substantiated value, as the water volume let out from the lake has extremely different value in different hours of the day, and nobody and nothing, but the equipment, was able to record the water volume flowing through the tunnel.
What about the changes in Lake level, as of January 1, 2002 the lake level made up 1896.32 meters, while as of 1 January 2015 the lake level was 1900.13 meters, i.e. the total increase made up 3.81 meters, where an increase of 2.47 meters made up for 2002-2007 and 1.34 meters for 2008-2014 (including added 20 cm based on the specification of land surveying).
During spring floods the highest indicators were recorded in 2007 and 2010, 2002-2004 also had high indicators, while 2008, 2012, 2013 and 2014 recorded low values.
What about forecasts in regard with changes in lake level during 2015, it should be said that factors needed for the change in the lake level – available snow reserve and hydrometereological conditions are more favourable than for 2014, while the forecasts for the change in the lake level will be presented in the third week of March.
February 17, 2015 at 13:03