Project snapshot: Hydroelectric project takes unprecedented measures to protect habitat
Reventazón hydroelectric project, Costa Rica
Hydroelectric projects produce renewable energy, but they can also have serious environmental and social impacts. Dams block free-flowing river ecosystems and prevent fish migrations, and the reservoirs they create may block the movement of terrestrial species.
Latin America is in the midst of a boom in hydropower construction, making it all the more urgent to protect habitat in a project’s entire area of biological influence—terrestrial as well as aquatic. Achieving this goal is a major challenge confronting the region’s power utilities.
With this in mind, Costa Rica’s national power company(the Instituto Costarricense de Electricidad, ICE), the IDB, and an international conservation organization are turning a major hydroelectric project on the Reventazón River from a potential environmental liability into a net gain for habitat protection. In addition to meeting 10 percent of the nation’s electricity needs, the project will:
- Lead to the protection in perpetuity of a free-flowing river system with largely intact ecosystems
- Safeguard critical habitat that will support a program to ensure the survival of the Americas’ most emblematic and enigmatic carnivore: the jaguar.
The Reventazón, which flows from the country’s central highlands to the Caribbean Sea, already has three hydropower plants in its middle and upstream sections. The Reventazón Hydroelectric Project, financed with the help of an IDB loan for US$200 million, will be located downstream of the existing dams, where the central highlands give way to the coastal banana-growing region.
Corridor for big cats. One concern in designing the project was loss of habitat connectivity caused by its reservoir, which is 8 kilometers long and covers 6.9 square kilometers. This new barrier would cut through the Barbilla Destierro Biological Subcorridor (SBBD)—a critical pathway for jaguars along Costa Rica’s Volcanica Central Talamanca Biological Corridor and for the Mesoamerican Biological Corridor as a whole.
Although the SBBD is far from pristine forest, its patchwork of pastures, farms, tree plantations, communities, and blocks of forest have been designated as part of the Path of the Jaguar by the international nongovernmental organization Panthera. According to Panthera, such human landscapes are fully usable by jaguars, which only need a place where they can pass through unharmed in search of prey and mates.
Under the IDB’s policy on environmental safeguards, the SBBD’s designation as a critical natural habitat requires that ICE restore habitat to preserve the subcorridor’s role in safeguarding the movement of jaguars and their genetic flow. ICE will meet these requirements by taking measures to protect land along the southern, eastern, and western portions of the reservoir at higher and more permanent levels than at present. The project will also help restore degraded lands and improve local understanding of the need to maintain this key biological corridor. In addition, the project will set protection goals and measure compliance by carrying out an initial Rapid Ecological and Social Assessment, establishing monitoring indicators, and undertaking regular third-party monitoring.
The project’s win-win protection measures have won general support from the SBBD’s residents. Included will be payments to forest owners for environmental services as well as support for environmental education, restoration of degraded lands, agroforestry, and technical support. For example, farmers will learn how to raise pigs in enclosures rather than letting them run free. In this way, the pigs’ waste can be converted to fertilizer and gas and will not affect water quality in the reservoir. At the same time, the animals will be less exposed to jaguar predation, reducing the potential for conflicts between farmers and conservationists.
Region’s first river offset. The new hydropower project, in conjunction with the other projects upstream, will substantially reduce the ability of the Reventazón River to support three migratory fish species. The IDB requires an offset for the river’s loss of capacity to support these species.
ICE will take the unprecedented step of protecting migratory routes for these fish species in perpetuity in the ecologically similar Parismina River, which joins with the Reventazón on the coastal plain. The offset agreement guarantees that artificial modifications, including dams that would block migrations, will be prohibited and that the Parismina’s natural flow pattern and its biological integrity will be preserved or restored where required.
Throughout the Parismina and Reventazón watersheds, ICE will work with landowners to reduce erosion, sedimentation, and pesticide runoff into the rivers. Other measures may result in net habitat improvement in the Parismina watershed. For example, restoring riverbank vegetation could create additional jaguar habitat and connectivity extending from Tortuguero National Park on the coast up into the central mountain range. The effectiveness of the protection measures will be verified through a permanent program to monitor water quality, biodiversity, and key habitats.
Need for new capacity. In the new project, ICE’s legal responsibilities for environmental protection will extend far beyond protecting the Reventazón’s water resources. The company must now safeguard biological connectivity over large terrestrial areas and throughout entire river systems. ICE will meet this new responsibility by working in partnership with the many actors in watershed management, including local municipalities, farmers, conservation organizations, and national agencies. This multistakeholder approach to regional watershed management is a critical element of sustainable hydropower.
With the IDB’s support, ICE will strengthen its environmental capacity as well as contract with outside experts to support corridor design, river offsets, biodiversity assessment, data compilation and analysis, and management of some of the target species. An existing law that supports ICE’s efforts to conserve the Reventazón watershed is being expanded to include the entire Reventazón-Parismina basin.
The project will set a new standard for habitat protection not only for hydroelectric projects in the region but for large-scale infrastructure works in general. In some respects, however, the Reventazón project is unusual. In most cases, different companies―generally private firms―exploit resources in a given area, making it difficult to determine which company should take responsibility for environmental mitigation. But ICE operates all the hydroelectric projects on the Reventazón. Moreover, its status as a public-private company helps to ensure close working relationships with its government agency counterparts and permanent protection for the watershed and the biological corridor.