The president of the environmental organization Sélvame, Guillermo D. Christy, revealed that the collective is preparing a new series of legal injunctions to halt the construction of the Tulum bypass. This 26-kilometer bypass, a critical infrastructure extension of the Maya Train project designed to connect the station with the new Felipe Carrillo Puerto International Airport, has drawn sharp criticism for advancing over the fragile Sac Actun cave system despite being officially shuttered by environmental authorities.
The legal offensive follows reports that construction of this bypass has persisted clandestinely, defying a closure order from the Federal Attorney for Environmental Protection (Profepa). According to Christy, the project represents a flagrant violation of environmental law, operating under an opaque "exception" granted by federal agencies to facilitate the military-led expansion of the Maya Train corridor. The conflict underscores a deep structural tension between the federal government’s drive for rapid development and the survival of the world’s most significant underground river network, which rests directly beneath the proposed road.
A Path Set in Stone: The Tulum Bypass Impact
The Tulum bypass was conceived as a logistical necessity to alleviate the crippling traffic on Federal Highway 307. By creating a direct route to the stations of the Maya Train and the sprawling Parque del Jaguar, authorities argued the project would modernize the region's mobility. However, the chosen trajectory cuts six kilometers westward into the jungle, positioning heavy machinery directly above the Sac Actun system.
This flooded labyrinth spans more than 368 kilometers, connecting over 220 cenotes and housing invaluable archaeological and paleontological remains. Environmentalists argue that the structural load and chemical leaching from the construction threaten to collapse the delicate limestone ceilings of the caverns. "We conducted a field survey and realized that work has continued practically since the closure was first announced," Christy reported. "The work is being carried out illegally, buoyed by a Semarnat exception that allows the Maya Train's builders to bypass standard environmental impact assessments."
The Secretariat of National Defense (Sedena), which oversees the project, reportedly began clearing the jungle in April 2025. At the time, the project lacked a valid Environmental Impact Manifesto (MIA). While Profepa initially halted the works following complaints from local residents and scientists, the recent granting of administrative shortcuts by the Secretariat of Environment and Natural Resources (Semarnat) has permitted the heavy machinery to return to the sensitive karstic terrains.
The Aquifer and the Tulum Bypass Under Siege
The environmental stakes extend far beyond the loss of jungle canopy. The region’s aquifer, the primary source of fresh water for the entire Riviera Maya, is already in a state of alarm. Christy noted that between 7,000 and 15,000 concrete and steel columns have been driven into the groundwater to support the Maya Train and its associated infrastructure. These pilots are now corroding, releasing heavy metals and pollutants directly into the water supply.
The crisis is exacerbated by the explosive growth of Tulum's urban and tourist footprint. More than 600 real estate developments have been constructed in recent years, many of which lack functional drainage systems or wastewater treatment plants. Sélvame reports that 90 percent of the monitored wells and cenotes in the region show severe levels of contamination. "The real intention of this bypass is not mobility," Christy argued. "It is a spearhead for real estate speculation, designed to lotify virgin land for developments that should be considered illegal from their inception."
The environmental group previously proposed a less invasive alternative: a smaller bypass positioned closer to the existing urban sprawl of Tulum. This route would have utilized existing service roads and avoided the fragmentation of large jungle tracts, a proposal that Profepa reportedly viewed favorably before it was ultimately discarded by the federal government in favor of the current western expansion.
The Tulum Bypass and a Heritage at Risk
The area currently being cleared is not only an ecological filter but a global cultural sanctuary. UNESCO has been considering the Sac Actun system for declaration as a World Heritage site due to the presence of 10,000-year-old human remains and extinct megafauna fossils. The heavy vibration from bypass construction and the risk of cavern collapse represent an irreversible threat to this "time capsule" of human history.
While Semarnat has made minor concessions, such as removing segments of the perimeter fencing to allow for wildlife crossings, activists maintain that these measures are insufficient to mitigate the structural damage. The ongoing corrosion of structural supports and the daily spill of construction materials remain unaddressed, creating a legacy of environmental debt that the region may struggle to repay.
The Legal Stand on the Tulum Bypass
The new series of injunctions prepared by Sélvame seeks to force a definitive halt to the works and a transparent review of the Semarnat exceptions. The legal challenge aims to restore the primacy of environmental law over the administrative decrees that have shielded the project from public scrutiny. For the defenders of Sac Actun, the battle is not just against a road, but against a development model that risks the very natural assets that made Tulum a global destination.
As the legal proceedings move through the federal courts, the machinery remains active in the jungle. The outcome of this legal siege will signal whether the Riviera Maya’s most important resource, its water, can be protected against the unyielding momentum of federal infrastructure expansion. The decision will define the environmental viability of Tulum for the next century.
Is the construction of the Tulum bypass worth the risk of permanent damage to the Sac Actun aquifer? Join the conversation and share your perspective with us on Instagram and Facebook at @thetulumtimes .