A Mexican court has suspended development of a US$15 billion liquified natural gas (LNG) terminal on the Gulf of California, a Unesco World Heritage site that teems with wildlife that includes turtles, whales, dolphins and hundreds of species of fish.

The project, known as Saguaro Energía, would transport natural gas through a 500-mile pipeline from the Permian Basin in West Texas to the coastal town of Puerto Libertad in Sonora state, Mexico. There, the gas would be liquified and exported on tankers to Asia, says Saguaro’s owner, U.S. energy company Mexico Pacific.

The terminal is the largest of several planned in Mexico, where access to the Pacific shortens routes to Asia. The United States has become a major exporter of natural gas in recent years, and U.S. President Donald Trump’s decision to allow new export permits has boosted interest in building LNG terminals in Mexico.

But Saguaro and the prospect of other, smaller such projects in Mexico have met with resistance from dozens of local and international environmental organizations. The critics say it would jeopardize a marine habitat of almost unparalleled biodiversity, pollute Mexican communities and damage desert land along the pipeline’s route to the Gulf. “The great biological wealth of the Gulf of California is unique in the world,” says Alejandro Olivera, Mexico representative for the Center for Biological Diversity. Saguaro is an “absolutely reckless” threat to a habitat that, for example, supports five of the world’s seven species of sea turtle.

The Saguaro terminal would initially be able to produce 15 million metric tons of liquid gas per year. It is one of three projects planned for the eastern coast of the Gulf, a 1,100-kilometer (700-mile) strip of sea between the Mexican mainland and the Baja California peninsula.

The terminal would allow Mexico Pacific to cut shipping times to Asia by 11 days and vessel emissions by 60%, the company says. But environmental experts worry that 1,000-foot tankers plying the narrow gulf would kill dolphins and whales and create noise that would disrupt the cetaceans’ communication.

Mammals found in the gulf include blue whales (Balaenoptera musculus), fin whales (Balaenoptera physalus), and sperm whales (Physeter macrocephalus), all of which are listed as endangered. Shipping would also threaten the gulf’s fisheries, which account for half of Mexico’s catch, experts say. The critically endangered vaquita porpoise (Phocoena sinus) lives in an area north of the planned terminals.

Various impacts cited

Meanwhile, the process of piping gas from Texas to the Mexican coast would damage habitats along the route through the states of Chihuahua and Sonora, says Carlos Demetrio Olvera, director of eSkuela Radical, a grassroots organization based in Chihuahua, Mexico. In addition, the liquefaction process in Puerto Libertad would release pollutants such as carbon monoxide, sulfur dioxide, nitrogen oxides and require huge amounts of energy.

There is also the question of climate change, experts say. LNG is billed as a lower-carbon alternative fuel, but the process of extraction, liquefaction, shipping and regasification adds significantly to its carbon footprint. A study published last year by Robert Howarth, an ecologist at Cornell University, calculated that its global warming potential over 20 years is a third greater than that of coal.

“Everyone hears the word ‘natural’ and thinks it is something that’s clean,” Olvera says, referring to LNG. “People have no idea.”

The Mexican Secretariat of the Environment and Natural Resources (Semarnat) announced in March that Saguaro Energía had been frozen by five preliminary court injunctions. In a statement, Semarnat noted no project permits have been granted by the government of Mexican President Claudia Sheinbaum, which was committed to “protection of the environment.” Mexico Pacific, for its part, did not respond to an email requesting comment.

Little has been made public about the injunctions. Two of the petitions were filed in a Sonora court by a group of Mexican and international environmental organizations that asked not to be named for security reasons. The identities of the other petitioners and their arguments remain secret. Violence against environmental defenders in Mexico is common, and Sonora has a strong organized-crime presence.

Old permit, new project

Jacob Kopas, a senior attorney at Earthjustice, a San Francisco-based environmental law organization that advised green groups on two of the petitions, says those cases hinge on two main contentions. The first is that the Mexican government allowed Mexico Pacific in 2018 to repurpose a permit for a defunct 2006 gas project without doing a new environmental impact assessment. The original project—designed when the U.S. was a net importer of natural gas—would have brought liquid gas to Puerto Libertad by sea and converted it to gaseous form for use in the American market.

The developers “tried to dust off” the old approval and “revamp it into an export project,” says Kopas. Plus, Mexico Pacific significantly expanded the project’s scale. The environmental impact of liquifying gas is different from regasification and should require a new assessment, he argues. Tankers arriving full to unload cargo presents different challenges than the other way around, experts say, pointing out, for instance, that empty tankers would release ballast water from other seas into the gulf, introducing pollutants and invasive species.

The petitioners also argued that Mexican authorities are obligated to assess a project’s climate impact, says Kopas. The 2006 permit included no such assessment. The injunctions will remain in place until a judge rules on each one—a process that people familiar with two of the injunctions believe could take many months.

Meanwhile, Mexico Pacific’s financial ownership and corporate leadership recently changed, and the company has yet to make a final investment decision on the Saguaro project—a sign, say Saguaro’s opponents, that the project might be in trouble.

Cecilia García Muñoz, director of an online campaign, named #esgasfosil, to stop LNG projects in the gulf, still views the project as a threat. Until the court shuts it down definitively, she says, “we have to keep fighting.”