UIS Commission on Karst Hydrogeology and Speleogenesis

In the period of August 7 ? September 3, 2009, the Ukrainian Speleological Association have conducted the regular expedition of the project to continue exploration of Krubera (Voronja) Cave and other caves of the Ortobalagan Valley in the Arabika Massif (Western Caucasus).

In this expedition, led by Yury Kasjan, 52 cavers participated from Ukraine, Russia, Moldova and Israel. A separate team of 20 cavers from Lithuania, Hungary, Spain, Ireland and UK, led by Ajdas Gudajtis (Lithuania), have also worked in Krubera under close coordination with the Ukr.S.A. expedition.

The major effort of the Ukr.S.A. expedition was focused on the Nekujbyshevskaya Branch, a distinct branch diverging from the main one at -250 m and stretching to the north-west, in the direction opposite to the overall trend of the Main Branch. Starting from the depth of about -750 m, the Nekujbyshevskaya Branch turns to south-east and stretches toward the deep section of the Main Branch.
This branch had been explored by the previous Ukr.S.A. expedition in 2008 to a siphon at -1384 i. Now this siphon has been tested but turned to be narrow and choked by debris. Nevertheless, a bypass for this siphon has been found, which led to a new part explored and surveyed during the expedition for depth of 170 m and length of 1251 m. Depth of the Nekujbyshevskaya Branch has reached 1557 m, and total length of the Krubera Cave became 15486 m. Depth of the Krubera Cave, the deepest cave in the World, remains at -2191 m, as established by a 46 m deep dive in the terminal siphon in the Main Branch performed during the 2007 Ukr.S.A. expedition.  
 
Yury Kasjan, Kyrylo Markovskoy, Gennady Samokhin and Alexander Klimchouk,
the CA Project co-ordinators