A Restoration Effort in Southcentral Chile Aims to Renew a Damaged Wetland

The pioneering Americas Flyways Initiative project offers new promise for both migratory shorebirds and local communities increasingly threatened by flooding in a changing climate.
An aerial view of the confluence of the wetland and urban sprawl.
The city of Talcahuano runs into and over the Rocuant-Andali茅n wetland. Today urban infrastructure prevents rainwater from seeping across the landscape and being absorbed. Photo: Katherine Sanhueza Bravo

Luisa Valenzuela, an environmental advocate in southcentral Chile, vividly recalls the moment she found her calling. It was a spring day 18 years ago when, from the doorstep of her home in Hualp茅n, she watched a pair of ducks flap their wings desperately at a truck illegally dumping debris into the Vasco Da Gama-Chimalfe, a wetland that abuts her neighborhood. She suspected the birds were protecting their eggs or chicks. 鈥淭hat day I promised the wetland that I would become the voice for the species that live there,鈥 she says. 

Valenzuela founded the Vasco Da Gama-Chimalfe Wetland Defense Committee and dedicated her life to safeguarding the habitat, which is part of a larger network of coastal wetlands in and around Concepci贸n, Chile鈥檚 second-largest city after Santiago. The Rocuant-Andali茅n鈥揤asco Da Gama鈥揚aicav铆鈥揟ucapel Bajo Wetland System spans 11 square miles and is under threat from industrial expansion, urban development, and pollution, all of which have drastically reduced its size. 鈥淲hat we see today is just a remnant of a once-vast wetland,鈥 says Heraldo Norambuena, a biologist specializing in natural resource management at the Universidad Santo Tom谩s. 

As a result, there鈥檚 less habitat available for birds that have long depended on the wetlands, from residents like Yellow-billed Pintails to vulnerable Lesser Yellowlegs that fly here from northern Alaska. 鈥淩eturning to these sites is part of their historical memory,鈥 Norambuena says.

This habitat loss has also undermined the ecosystem鈥檚 role as a natural buffer against floods, says Octavio Rojas, a disaster risk management expert at Universidad de Concepci贸n. Today, urban infrastructure prevents rainwater from seeping out across the landscape and being absorbed. This has left metropolitan areas vulnerable to flooding, a hazard that is likely becoming more frequent and intense due to climate change鈥攚ith deadly consequences.  from heavy rainfall in June 2023, for instance, forced the evacuation of thousands of residents in south and central Chile and killed two people. 

A new $147 million wetland revitalization project aims to turn things around. The project is a pilot of the Americas Flyways Initiative (AFI), a collaboration between 探花精选, BirdLife International, and the Development Bank of Latin America and the Caribbean. Harnessing a mix of funding and working with communities, AFI has set out to facilitate 30 nature-based economic development projects that protect and restore critical ecosystems by 2050.

Starting with southcentral Chile, the initiative aims to increase the connectivity and conservation of sites crucial to migratory birds, which are experiencing  population declines. Renewing the wetland system鈥檚 natural ability to mitigate flooding will also benefit residents. 鈥淚t鈥檚 a win-win,鈥 says Santiago Aparicio, director at the Americas Flyways Initiative for 探花精选. 鈥淏y protecting birds, we ensure better conditions for other species鈥攊ncluding ourselves.鈥

New Appreciation for an Undervalued Landscape

For decades, wetlands in the communities of Hualp茅n, Concepci贸n, Talcahuano, and Penco were considered worthless land. Development advanced over them, filling them in to make way for roads, ports, Carriel Sur International Airport, and industrial zones.

Yet these ecosystems play important roles. They help mitigate climate change by storing carbon. They regulate ecological balance: After Chile鈥檚 devastating 2010 earthquake, the Rocuant-Andali茅n wetland in Talcahuano buffered the impact of the resulting tsunami, some researchers maintain. And even though they are diminished, their diverse habitats鈥攚hich includes marshes, swamps, riparian zones, and estuaries鈥攕upport an array of coastal and marshland bird species. The Rocuant-Andali茅n wetland, home to American Oystercatchers and 150 other birds, is of such importance to avian conservation that BirdLife International designated it a global Important Bird and Biodiversity Area in .

Without legal protection, urban planning has long overlooked the region鈥檚 wetlands鈥攂ut local communities haven鈥檛. For years, neighborhood groups, including Valenzuela鈥檚, have been clamoring for greater habitat protection. They鈥檝e promoted community science to monitor the ecosystems, filed environmental complaints, and raised awareness through neighborhood tours and school workshops.

In 2019, a regional municipal coalition succeeded in having the wetland system declared a priority site for conservation鈥攁 designation that promotes protective measures but doesn鈥檛 preclude development. The following year, boosted by widespread public support, Chile enacted the Urban Wetlands Law, which allows the national government to designate wetlands within city limits. The law aims to stop indiscriminate real estate development in those habitats and integrate them into city planning for flood mitigation, recreation, biodiversity, and other factors. 

Against this backdrop the Americas Flyways Initiative assembled a consulting team to figure out which interventions would have the greatest benefit. The group included hydrologists, disaster risk specialists like Rojas, biologists like Norambuena, and community leaders such as Valenzuela. They knew, says team leader Carolina Rojas, that to get buy-in from locals and private landowners, they would have to integrate the wetlands into the urban matrix in ways that balanced community needs, including additional housing and access to public space. 鈥淎FI does not seek to impose restrictive barriers,鈥 says Rojas, who is a geographer with the , a Chilean research organization. 

At the same time, Octavio Rojas says, the primary goal is to restore the system鈥檚 water flows 鈥渢o give back its sponge-like capacity.鈥

In weighing their options for doing so, the team drew largely on two studies by Chile鈥檚 Ministry of the Environment: one that  zones most in need of restoration, and another that  a land-use plan to build system-wide resilience. 

Ultimately they proposed three floodable parks across the wetland system.

Ultimately they proposed three floodable parks across the wetland system. To slow runoff and allow water to more readily soak into the ground, each area will contain green infrastructure such as rebuilt natural contours and native vegetation. A mix of restored habitats will support resident and migratory birds alike. People, meanwhile, will enjoy new open spaces and trails鈥攁nd greater safety from extreme flooding amid an increasingly chaotic climate.

While not all of the areas identified are currently protected under the urban wetland law, the AFI team hopes that the ecological and societal benefits that restoration promises will encourage their designation.

Loretto Arriagada, coastal resilience conservation manager in Chile for 探花精选鈥檚 Latin America and the Caribbean program, is quick to point out that restoring wetlands provides economic benefits, too: reduced flood damage, more bird tourism, and carbon offsets generated by natural storage of CO2. Such benefits are significant鈥攁nd so is the work that it will take to achieve them. 

A Better Home for Birds

In early March, Arriagada and wildlife conservationist and photographer Katherine Sanhueza Bravo drive to one of the most threatened areas that migratory birds rely on, according to AFI鈥檚 analysis. The Rocuant-Andali茅n wetland contains some of the healthiest intact habitat, but decades of neglect and abuse have significantly degraded the natural landscape in a portion called Carriel Norte, where Greater Concepci贸n is encroaching. But it鈥檚 not just urban growth threatening this sector. An active industrial zone brings persistent problems: garbage accumulation, stray dogs that prey on birds, poor waste management.

鈥淟ook at how the wetland has been filled in,鈥 says Arriagada. Ahead lies a maze of landfills that have multiplied over time, forming up to 15-foot-high mounds of sand over what were once reedbeds.  

Even among these artificial hills, amid piles of dirt and cement, birds persist.

Even among these artificial hills, amid piles of dirt and cement, birds persist. Southern Lapwings, with white chests and black crowns, wander unfazed by the constant truck traffic. Lesser and Greater Yellowlegs feed on macroinvertebrates in the riverbed, fattening up in preparation for their impending journey north. In the distance, canals connected to marshland play seasonal host to Hudsonian Godwits and Whimbrels. Their calls, says Sanhueza, are like the soundtrack of the wetland system.

Like many people in the region, Sanhueza didn鈥檛 know she lived on a wetland鈥攗ntil she read a sign while biking through Rocuant-Andali茅n on her way to university. 鈥淲hen people鈥檚 homes flood in winter, they see it as a problem,鈥 she says. 鈥淏ut once they understand the wetland, they realize restoring it actually helps reduce flooding.鈥

Sanhueza has made it her mission to help others discover these hidden ecosystems. She founded a bird guide company, , to spread enthusiasm for the wetland and the birds it supports鈥攅ven in a diminished state. 鈥淏irds are stubborn,鈥 she says. Humans are too, she adds鈥攎any remain in the neighborhoods surrounding Carriel Norte despite the flooding and pollution. 

Arriagada nods, then notes there鈥檚 a key difference. Birds are resilient, but they can鈥檛 address the threats to the habitat they depend on. 鈥淚t鈥檚 our responsibility to manage and reduce them鈥攖o stop degrading these ecosystems,鈥 she says.

As AFI restores crucial wetland habitat in the coming years, it could mark a major turning point in bringing about that change.

This story originally ran in the Fall 2025 issue as 鈥淣atural Allies.鈥 To receive our print magazine, become a member by .