[Aztlan] Chichen Itza water sources

[Bruce Rogers]

Listeros,

Yes, as Mary Hopkins pointed out, Cenote Sacrado is not Chichen 
Itza's domestic water supply. Approximately a kilometer to the south 
is Cenote Xtoloc, also known as the Grand Cenote, that was the main 
domestic water supply.  There are also at least 9 other cenotes known 
within a kilometer or two of Chichen Itza.

The "DPW" Cenote - Cenote Xtoloc
The Cenote Xtoloc is about 30 m in diameter at the water line and 
about 20 m deep from the general ground surface to the waterline. 
Its walls are both steep with vegetation and soil cover (the east and 
south walls) and nearly vertical bare limestone (north and west 
walls).  The large pool covering the floor of the cenote has a large 
algae mat growing on its west side, but no larger aquatic plants grow 
in the pool. In 1936, F.G. Hall and others reported the pool was 
about 15.4 m deep with a silty bottom.

The water temperature during Hall's visit was recorded to be 27.3 
degrees C at the surface and 21.9 degrees C at the bottom of the 
pool.  The pH averaged 7.4 at the bottom (near neutral) and 8.6 at 
the pools surface (somewhat alkaline due to dissolved limestone). 
The cenotes pool surface represents a "stand pipe" in the local 
ground water table.  Flow across the cenote was estimated to be about 
1-2 m a year, about normal for some interior karst areas such as the 
Florida Peninsula, but extremely slow compared with David Hixson's 
coastal site of Chunchumil and the more interior site of 
Dzibilchaltun.

A rich fauna was collected from the pool by James Reddell in 1973 and 
included aquatic invertebrates and terrestrial and flying insects, 2 
species of fish, amphibians, and small rodents.

A trail spirals down from the northeast corner to the south wall; 
this trail was used to provide access to the pool's surface to 
collect water.  About 5 m above the pool is a small cave in the south 
wall of the cenote.  Cueva del Cenote Xtoloc is about 90 m long and 
consists of a single passage that has been enlarged by human 
activity.  The dry and dusty passage is about 2-4 m high (except a 
small area of collapsed blocks several dozen meters inside the 
entrance) and has a heavily coating of soot in its ceiling from long 
term use by torch-bearing visitors.

The fauna of this cave is typical of dry caves in the region with 
assorted invertebrates (including Tohila atelomna, a blind cricket) 
and a small colony of Common Vampire Bats (Desmodus rotundus 
murinus).  The cave is amazingly dry and the bat's waste products do 
not enter the surface runoff into the cenote.

It appears that the Maya used this cenote for domestic water since it 
was accessible and apparently the water was clean at the time of 
major use of the site by the Maya over the last 2700 years as it is 
today.

The Sacred Cenote - Cenote Sacrado
The somewhat oval Cenote Sacrado measures about 56 m by 65 m and its 
depth varies between 20 and 25 m, depending on yearly rainfall. The 
pool at its base is about 12 m deep and the bottom is covered with a 
10 to 20 m thick carpet of detritus.  The walls of the cenote are 
essentially vertical with horizontal solution pockets scattered at 
various depths and an irregular, undercut notch along the north and 
west sides of the pool at the water line.  A fairly extensive algae 
mat covers much of the pool's surface as Sam Edgerton remarked. 
Water temperatures are similar to those at Cenote Xtoloc, but the 
water chemistry is somewhat more alkaline due to the bat guano that 
constantly rains down into the pool as mentioned by Mary Hopkins.

The first successful recovery of artifacts was by Edward H. Thompson 
between 1904 and 1907 using a dredge.  Several SCUBA expeditions 
between 1961 and 1970 have had more success.  The 1971 expedition by 
Ediger brought in a large chlorination plant built by Clorox to clear 
the water.  While this did help the visibility for the divers, it 
also killed off much the indigenous aquatic life in the cenote; the 
cenote has never recovered.  No systematic study has been made of the 
cenote, but sampling of the cenote in 1973 revealed only 2 species of 
fish, turtles, frogs, and American Black vultures (Coragyps atratus).

Drains and Chultuns?
The area surrounded by the Thousand Columns Group in the eastern 
restored section of the site has several sub-floor drains.  These 
might lead to water storage chultuns, but not having knowledge of the 
layout of this unexcavated part of the site, this is speculation on 
my part.

Cheers,
Bruce Rogers, earth scientist & speleologist on a good day