photo: Connor Roe in sump 1 of the Huautla Resurgence. Photo by Chris Jewell.
The goal of the 2017 expedition was to find the way on further upstream, following the main flow, to continue exploration towards sump 9 in San Agustin. In 2016, several sumps were found along a major dry cave passage, now known as the Passage of the Cheeky Monkey. Nevertheless, at its most northern (upstream) extent, the main flow seemed to come out of a small flowstone restriction (see photo below) which stopped further exploration, and hence the main goal of this expedition was to find either a sump or a dry cave lead to bypass this obstacle. To allow for more exploration time beyond the first two sumps, with a combined length of approximately1.6 kilometres and maximum depth of 65 meters, two three day camps were conducted in the Passage of the Cheeky Monkey. During several dives, both the sump pool closest to the flowstone restriction and several leads in sump 2 were pushed without success.
On the other hand, a climb in the Passage of the Cheeky Monkey, which has been missed in 2016, led to some of the most amazing cave passage the team has ever explored (see photos below). These passages were full of dry gour pools, delicate formations, and coated in bright white calcite over all walls. Some parts of this newly discovered fossil cave passage, now known as The Dead Sea, were also the last resting spot for a large amount of scorpions.
Another climb in the Passage of the Cheeky Monkey, located at its southern (downstream) end above the sump pool, led via a large fossil passage to the top of the two sump pools discovered by Jason Mallinson during the 2001 expedition. In 2001, Jason found these sump pools by diving through sump 2, but could not get out of the water due to steep mud walls surrounding the sump. One mystery solved.
In total 1.5 kilometres of cave was found, taking the total cave length to 3.8 kilometres. Several leads remain, both in the dry cave and underwater. The hydrology of the cave is still a mystery - how can enough water come through this flowstone restriction to destroy almost all of the cave line the team laid through the sumps in 2016? Has an underwater route been missed? While exciting discoveries were made on this trip, many questions remain, asking for a return trip in the future.
Further reading:
Klocker, 2018, Beyond the Sump: Exploration of the Huautla Resurgence. NSS News, January 2018:4-9. [pdf]