Costa Rica’s long-running plan to build an international airport in the country’s southern zone is once again moving forward, reviving a project that supporters see as a path to economic growth and critics warn could bring lasting environmental and social damage. The proposal has been circulating since about 2004.
It first gained traction under former President Laura Chinchilla, who promoted it as a way to spur development in the south, with construction expected to begin before her term ended in 2014. That did not happen. Since then, the airport has been revived, stalled, reduced in scope, and revived again under successive administrations.
President Rodrigo Chaves’ government has renewed the push, promising an airport in the Osa area to promote development in the southern region. The project, now referred to as the Aeropuerto Internacional de la Región Brunca, was included in the National Development and Public Investment Plan 2023–2026.
The current version is far smaller than the original proposal. Early plans envisioned a large international airport with a runway capable of handling an Airbus A380, but that concept was shelved because of cost and environmental concerns. The project is now estimated at $42 million.
Under the revised plan, the airport would have a 2,600-meter runway, 45 meters wide, designed to receive medium-range aircraft carrying 180 to 200 passengers, mainly from North America. It would also include a terminal, apron, taxiway, and services for executive aircraft. The proposed site is in Sierpe, in the canton of Osa.
Environmental impact studies have already cost more than $1 million. Civil Aviation also downgraded the project from a large international airport to a Category B facility, aimed at charter and similar flights, in an effort to keep it financially and technically viable. Authorities have promoted it as Costa Rica’s first green or ecological airport. Construction has most recently been projected to begin around 2027.
Supporters argue the region has a strong economic case. Travelers currently face a drive of more than seven hours from San José’s airport to Corcovado National Park, and about six hours to Drake Bay. Direct international access, they say, would open the southern Pacific to a much wider tourism market and help reduce one of the region’s biggest barriers to growth.
They also point to the southern zone’s longstanding economic challenges. Compared with Guanacaste, which saw rapid tourism and infrastructure growth after the opening of Liberia’s international airport in 1995, the south has remained one of Costa Rica’s most marginalized regions. Backers say better air access could create jobs, support local businesses, and narrow that gap.
But the obstacles are substantial.
One of the most sensitive issues is displacement. Around 350 families in Palmar Sur could face eviction. Many do not hold formal land titles, despite having lived there for generations. Since the project was first approved by executive decree in 2010, residents have maintained steady opposition, and some are now considering legal action.
There is also concern over the airport’s proximity to the Diquís Delta archaeological zone, a UNESCO World Heritage Site known for its pre-Columbian stone spheres. Critics say construction threatens four archaeological sites within the Diquís park, and some local opponents are hoping future archaeological findings could slow or stop the project.
Environmental concerns extend beyond the immediate footprint of the airport. The proposed site lies next to the Térraba-Sierpe Wetlands, the largest wetland on Central America’s Pacific coast. The protected area covers more than 14,700 hectares of mangroves and provides habitat for 159 bird species, including rare and endemic species. Conservationists have strongly opposed building so close to such a sensitive ecosystem.
Financing remains another unresolved issue. Funding has never been fully secured, and civil aviation authorities have repeatedly weighed using their own budget or seeking international loans. That uncertainty has helped stall the project through multiple administrations.
The broader concern is what the airport could mean for Corcovado National Park and the Osa Peninsula as a whole. Corcovado, which protects the largest remaining stretch of primary rainforest on Central America’s Pacific coast, has long benefited from its relative isolation. That remoteness has limited visitor numbers and helped preserve one of the most biologically rich ecosystems in the region.
An international airport would change that. Local residents have already voiced concern after authorities doubled daily access to Corcovado’s Sirena Station from 120 to 240 visitors, warning that the park could begin to shift toward mass tourism. Biologists and conservationists say the main threat may not be the airport itself, but the development that would follow: more roads, more hotels, more speculation, and more pressure on fragile habitats.
For many critics, Liberia offers a warning. After Guanacaste’s airport opened, coastal towns such as Tamarindo and Playas del Coco saw rapid development. Opponents of the southern airport fear a similar pattern near Corcovado, where the ecological stakes are far higher.
There is also concern about aircraft noise and flight paths over sensitive rainforest corridors. Combined with new roads and tourism infrastructure linking the airport to park access points, critics say the project could fragment habitat that is still largely intact.
The debate over the airport reflects a broader question Costa Rica has faced for decades: how to promote economic development without undermining the natural systems that make the country distinctive. For the southern zone, the need for jobs and investment is real. But so is the risk of irreversible damage.
In Osa, the balance is especially delicate. Once intact rainforest is fragmented, it cannot be restored to what it was. The outcome of this project may shape not only the future of the southern zone, but the fate of Corcovado and the wider Osa Peninsula for generations.
