Sistema Ox Bel Ha:
Quintana Roo's newest giant

By Christophe Le Maillot

This is a quick month to month description of the 1998 and mid-1999 exploration project of this system (a connection between Sistema "Chik'in Ha" and "Esmeralda"). Using different configurations, approaches, and techniques, we patiently discovered what potentially could be the third largest underwater cave in the World.

A cave of this proportion offers a variety of distinct features. -A shallow portion (25 to 34 ft) is encountered from the main Cenote (Del Mar) up to 5000 ft upstream in a W/NW heading. The very swampy surrounding gives the cave a black coloring, very similar to Sistema Naharon. Various decorations can be observed throughout. Shallower rooms seem to present more formations. Eight different cenotes are scattered over this large area. A light flow can be felt at all times.

-Very large tunnels and huge chambers in the most western direction before getting to Cenote Canales. The average depth is 40 ft and the deepest section (Orion) is 47 ft. Halocline is found between 42 and 45 feet. Flow is always present. Decorated in some places. Beautiful Cenote 9000 ft from main entrance: De La Familia.

-A northern lead with a big, wide tunnel and complex side passage. Lots of breakdowns and tanic domes in which blind cave fish and isopods often can be observed. Lack of formations and halocline at 40 ft. Maximum depth is 55 feet.

-Three connections to the ocean via similar but separate ways. Going straight East, this complicated downstream becomes shallower closer to the sea. The flow gets extremely strong towards the exits. Sidemount configuration is necessary to go through several restricted parts. The bottom composition turns gradually to sand. Seafans, coconuts, and shells are a constant reminder of your close proximity to the ocean. The fresh and salt water only mix very near the surface (about 8 ft). All exits are located approximately 3/400 ft away from one another. Snappers and Grunts are found in large numbers in the short cavern zones of the exit cracks. Tarpons were encountered a thousand feet inside the cave (always a scary surprise).

-Deep canyons areas past Cenote Esmeralda from which depth range changes between 50 and 80 feet. These deeper salt water passages are highly decorated and contain fossilized sponges. The tunnels are big, with an average width of 40 ft.

A condensed exploration overview:

June 1998:

After a quick reconnaissance dive on the 3rd, we went back the next day to survey the 3,350 ft of existing lines from previous French and American projects, led at different times by Steve Keane and Tamara Kendell. Bernie and I laid 5,500 ft going straight east towards the ocean. This downstream section is characterized by narrow passages and a strong flow (lines: Al Mar, E Gate, Cabanas, and Mosquitia). Diving S/SW from the Main Entrance (Cenotes Del Mar), a 3,000 ft loop was added (lines: Labyrinth, Lab Conecter, L Line). Working around the nearby Cenote Mangrove and Tarpon, 3,500 ft was laid due west (Kite and All Black lines). From existing lines (names Wassy and Wussy), in a N/W direction, we squeezed this time with our sidemount configuration through the small Coconut Drive and D.O.M. Sections for 2,000 ft of new lines.

No. of dives: 12

Total Bottom Time: 2085 minutes

Total line surveyed: 15,500 ft. Total line laid: 12,150 ft.

Explorers: Bernie Birnbach, Bil Philipps, Christophe Le Maillot


July 1998:

Excited by the previous month's progress, we decided to focus our exploration mainly upstream, where the cave seemed to be the most promising. After 5 dives, we laid more than 10,000 ft. To the NW we added to the map the following lines: KFC, Magic, Aves, Arbol and 1 Cenote: La Meza. The main passage turned west, to run 2,150 ft (Low Land line) to the beautiful Cenote De La Familia.

Moving north from the Wassy Line, on later dives, we encountered a shallow and decorated cave (DOM 2) at first, which extended after only 1,000 ft to a deeper section (Rimet) with halocline visible at 38 ft. In two different dives, we joined Bernie's Aves line with Rimet (Der Konnector: 900 ft) and found a lead going SE (Syphon Norte). Towards the end of the month, during 5 long dives, Daniel Riordan helped us push the Rimet section for another 7,400 ft. The end of the line is now 10,046 ft from Main Entrance.

No. of dives: 15

Total Bottom Time: 3407 minutes

Total line laid: 23,786 ft

Longest penetration from Main Entrance: 10, 046 ft

New Cenotes: La Meza, Victoria, De La Familia

Explorers: Bernie Birnbach, Daniel Riordan, Christopher Le Maillot


August 1998:

The objective for this hot summer month was to connect the cave to the ocean. From the shore, we observed 4 rushing streams of fresh water exiting furiously into the ocean. They were spaced out by 400 ft regular intervals from the Cabana Tulum Hotel continuing southbound. Our existing eastern line: E Gate and Al Mar were going towards the sea but the strong flow made us think twice about trying to connect them from the cave.

We divided into two teams and fought an extremely severe current. Both teams finally connected at two different spots after only 600 ft (the E Gate line - exit 1). The next exits were eventually connected: #2 after 550 ft of narrow passages; and #3 a few days later with a smaller entrance but a better defined tunnel to Al Mar section. Exit 4, however, was too restricted to allow us to squeeze further in.

Only a few dives upstream were made during the remainder of the month, adding "Ball Park" to the end of "Lowlands" for another 2,450 ft (still going big W/NW) and an off shoot passage of 1,400 ft (Sickman's Passage) to the main "Rimet" Section.

No. of dives: 10

Total Bottom Time: 1270 minutes

Total line laid: 9,190 ft

Explorers: Bernie Birnbach, Daniel Riordan, Christophe Le Maillot, Fred Devos


September and October 1998:

Our idea was adding several thousand feet of cave string to the end of the enormous "Ballpark" and "Rimet" sections. We used set up dives to avoid losing too much time going through the first restricted part of the system with too much equipment. After a couple of failed attempts, we managed to extend "Ballpark" by 2,000 ft and finding a small cenote (Luz). On 6/10, we returned adding Orion to the chart for another 3,000 ft and setting our personal penetration record to 14,000.

No. of dives: 6

Total bottom time: 1343 minutes

Total line laid: 5,000 ft

Longest penetration from Main Entrance: 14,000 ft

Explorers: Bernie Birnbach, Christophe Le Maillot


November and December 1998:

We discovered two more sections, off our two main upstream tunnels: "Blind wall", and "Black hole". Cutting SW/S/SE for 2,800 ft from the "Ballpark" line and "El Tucan" out of "Rimet" which ran SE in a twisted and complicated way.

No. of dives: 2

Total Bottom Time: 715 minutes

Total line laid: 4,500 ft

Explorers: Bernie Birnbach and Christophe Le Maillot

Total surveyed passage for the year: 58,000 ft


January, February and March 1999

A better land survey and a closer look at various aerial pictures, made us realize the extreme proximity of Sistema "Esmeralda". In fact, Cenote "Luz" could probably be part of "Canales," the massive downstream Cenote of this system. We thought that from the "Orion" line we might be able to eventually connect to "Esmeralda."

Unfortunately, we laid a little more than 500 ft the first time, which looped back frustratingly to itself. However, our hopes were not deterred. On March 13th, we headed instead for the "Ball Park" section. Here we found ourselves at 55 ft for a 350 ft run. It opened then to a shallower breakdown portion of the cave in which we swam against what appeared to be a very encouraging flow. We battled restrictions for another 600 ft carefully negotiating this very unstable collapse.

We finally tied in the unfamiliar line (Paso de Lagarto) not quite realizing yet what we really had accomplished. As a result, the connection between the two systems became Ox Bel Ha. We surveyed back to the main line adding shortly after 1,100 ft to the end of "Ball Park".

No. of dives: 7

Total Bottom Time: 1459 minutes

Total line laid: 4,300 ft

Explorers: Bernie Birnbach, Christophe Le Maillot, Esmeralda: Sam Meacham, Bil Phillipps, Fred Devos, Daniel Riordan

Total Length of Ox Bel Ha to date: 101,000

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Dedicated to the continued exploration of the world's largest underwater cave system.
Cave diving in cenotes and underground rivers in the Yucatan Peninsula,
Mayan Riviera, Quintana Roo, Tulum, Playa del Carmen, Mexico



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