San Agustin 2013

During previous visits to the Sistema Huautla in the remote Santo Domingo Canyon, 55m-deep Sump 7 had been explored for 150m, but this team hoped to penetrate further. This necessitated using the latest cutting-edge cave diving equipment, including cylinders filled with tri-mix (a mixture of helium, oxygen & nitrogen) as well as re-breathers and cylinders of specially mixed decompression gases. Entering the system via one of the lower entrances (Sotano San Agustin) they hoped to descend to a depth of 840m below it. Within a week the cave was rigged to Sump 1, and (underground) Camp 3 established at c700m. From here the divers conducted exploratory trips, including dives to 440m in Sump 9. 1774m of dry passages were surveyed but no by-pass discovered to Sump 9. In total, the expedition surveyed 2.7km of cave to a depth of 1545m, which means that Sistema Huautla is once again the deepest known cave in the Western Hemisphere.