Discover the Unknown
By Fred Devos
It was June 1st 1998, the official start of the rainy season here in Mexico's Yucatan Peninsula. Dive buddies Christophe Le Maillot from France, Bil Philips from Canada and myself were preparing to dive Sistema Del Mar (Of the Sea), a fairly new system. Its entrance is in a mangrove forest near the beach, a few kilometers south of Tulum Ruins where the Mayan civilization flourished until the 14th century.
Four months earlier Tamara Kendall, Ted Cole, Sue Sharples and Steve Keen made a few exploratory dives in this system but stopped because of bad roads and to concentrate on other projects.
Surveying and mapping
Curious about what they had discovered, we found ourselves bumping along the
road to 'Del Mar' with a truck full of tanks and gear. Fighting rain and mosquitoes,
we walked a short way to the entrance of Sistema Del Mar only to find a cenote
filled with milk. The draining rainwater had tinted the water white. We discussed
the dive plan and decided to survey the existing lines while eyeing up new leads
for future exploration, as no map was available.
Hints of larger passages
Equipped in side-mount and each carrying an extra stage, the three of us descended
through a small restriction and tied our guideline to an existing line. We immediately
observed two unique attributes of this system. First we found the mangrove swamp
above us made visibility less than normal. And second, the exciting discovery
of an unusually high flow hinting of larger passages upstream.
Following the guideline upstream through a dense forest of stalactites and
stalagmites, we found and later named two cenotes- Cenote Mangrove (due to its
surrounding foliage) and Tarpon Cenote (for the unexpected startle of a large,
silver-scaled specimen). Thirty minutes into the dive brought us to the line
ending where a huge passage waited to be discovered. We decided to contain our
curiosity and surveyed the existing line and its offshoots. After three hours,
we surfaced with a slate full of data, a smile on our faces and the resolve
to return soon.
First map
Back home we punched the data into a computer and printed the first map. Our
fellow explorers discovered about 6,000 feet of passage upstream to the North
but no line had been laid downstream towards the ocean.
Emptying reels
Bil went back to Canada so Christophe and myself continued the exploration
on our next day off. We added 1,400 feet of line upstream,
discovering larger decorated passages with coaxing leads in all directions.
Also, we followed the downstream flow through a few restrictions and a lot of silt.
The water cleared quite quickly and we spooled out 1,500 feet of line before
the flow became too strong and we had to turn around to begin pulling ourselves
out. We had just added
2,900 feet of line to the system. The high flow and numerous leads told us there
must be much more to discover. And we were right.
During the months of June and July, Daniel Riordan, a good friend of ours, joined the project and we continued to spend our days-off emptying reels of knotted line. Sistema Del Mar now stands at 39,000 feet of surveyed passages.
Six tanks, five hours
Most sections are huge and full with formations. Some rooms are the size of
soccer fields. Other passages
taper to side-mount or even no-mount restrictions. Haloclines sit at 39 feet
upstream and downstream at 22 feet. Although our push dives with scooters and
six tanks often entailed five hours bottom time, we rarely required decompression.
Sistema Del Mar has an average depth of 32 feet. We have discovered 14 new cenotes,
all of which are hidden in mangrove jungle. This makes entry or exits impossible
and so all of our dives begin and end at the original cenote.
14,000 feet penetration
So far, the furthest penetration from the entrance is 14,153 feet but set-up
dives have been planned for further exploration.
Connection to the sea ?
Our goal in the coming months is to extend this awesome cave and to search
for a possible connection to the ocean, making it the fourth system in this
area with a dive-able passage to the sea.
3/10/00
In December of 1998, three separate connections to the sea were established.
and on March 13th, 1999 Bernie and Christophe connected Sistema Del Mar at 62,333
ft (18,949 m) with Sistema Esmeralda at 38,000 ft (11,552 m). It was renamed
"Ox Bel Ha" and the explorers of both systems have joined forces as
G.E.O. (Grupo de Exploracion Ox Bel Ha). This incredible cave has since grown
to over 70 km along with the discovery of 42 new cenotes.