newmanl
Contributor
Unfortunately, the Yucatan was doomed from the start. The mostly agreeable weather, sand beaches and blue water for 'normal tourists' and the crystal-clear, seemingly limitless, flooded passages for cave divers served to attract development - and all it entails. The train (and airport in Tulum) are simply the latest insults to such a delicate ecosystem.
In a 2011 paper (Contaminants in the coastal karst aquifer system along the Caribbean
coast of the Yucatan Peninsula, Mexico) a survey of contaminants was made, finding numerous chemicals from agriculture (pesticides and fertilizers) and other industries, as well as chemicals (drugs) used by people, and sewage. Another paper (2020) surveying only 10 cenotes near Cancun found 50% were contaminated with fecal coliforms in the dry season (limited run-off) and 60% in the rainy season. As of 2011, only 32% of the Yucatan population was served by a municipal water treatment facility.
Finally, as a fish biologist, I made my own observations of the cenote fishes. It was obvious even in 2010 when I started cave diving that there were water quality issues. Many of the Mayan cichlids (Mayaheros uropthalmus) had signs of neuromast pitting (an erosion of the skin tissue around the sensory pores on the head and along the lateral line) and the mangrove mollies (Poecilia orri) had issues with sloughing slime from their bodies and fins. Both are indicators of contaminated water.
I was good with always having to apply 'ear beer' to avoid an infection, but knowing what I know now, I simply can't justify placing myself in that kind of risk for the sake of more Mexico cave diving.
In a 2011 paper (Contaminants in the coastal karst aquifer system along the Caribbean
coast of the Yucatan Peninsula, Mexico) a survey of contaminants was made, finding numerous chemicals from agriculture (pesticides and fertilizers) and other industries, as well as chemicals (drugs) used by people, and sewage. Another paper (2020) surveying only 10 cenotes near Cancun found 50% were contaminated with fecal coliforms in the dry season (limited run-off) and 60% in the rainy season. As of 2011, only 32% of the Yucatan population was served by a municipal water treatment facility.
Finally, as a fish biologist, I made my own observations of the cenote fishes. It was obvious even in 2010 when I started cave diving that there were water quality issues. Many of the Mayan cichlids (Mayaheros uropthalmus) had signs of neuromast pitting (an erosion of the skin tissue around the sensory pores on the head and along the lateral line) and the mangrove mollies (Poecilia orri) had issues with sloughing slime from their bodies and fins. Both are indicators of contaminated water.
I was good with always having to apply 'ear beer' to avoid an infection, but knowing what I know now, I simply can't justify placing myself in that kind of risk for the sake of more Mexico cave diving.
