GROUNDWATER FLOW AND WATER VISIBILITY AT SOME CENOTES IN THE YUCATAN PENINSULA

Yucatan Peninsula is a karst setting with many sinkholes (cenotes) of varying water quality. Some open cenotes have poor visibility and others are clearer, and they represent a tourist attraction both for locals and visitors. Activities like swimming and scuba diving in the cenotes are widespread in the area; in fact, the clarity of the cenotes is one of the decisive factors for tourists to pick one or another cenote, making this feature a key aspect of the region’s economy.

The key research question of this study was whether groundwater flow is related to water visibility in open cenotes in the Yucatan Peninsula or not. It is hypothesized that cenotes with poor visibility have overall lower groundwater flow velocity than the clearer cenotes. This work aimed to test the water visibility of some open cenotes, as well as their groundwater flow velocities, and correlate them at different depths. In various cenotes, measurements of single-point flows (velocity and direction) at different points and depths using an Aquadopp Profiler 2 MHz current meter were conducted. A detailed flow regime and a velocity profile with depth for each cenote were obtained and mapped. Water transparency assessment was done using the Secchi Disk method. Velocities in the cloudier cenotes ranged from 0 to 0.0052 m/s, and velocities in clearer cenotes ranged from 0 to 0.0177 m/s. These findings enhance our understanding of the complex karst system of the Yucatan Peninsula and provide important insights into the role of flow in the water clarity of cenotes.