The Reventazon Hydroelectric Dam is Central America's largest renewable energy project. In 2016 the 130 meter-high dam flooded the Reventazon Valley creating an 8-kilometer long artificial lake which completely dissects the Barbilla-Destierro Biological Corridor. The map below shows the geographical position of the new lake.
NEGATIVE ENVIRONMENTAL IMPACT
The creation of the Reventazon Reservoir has critically impeded the migratory flow of jaguars and several other species across the Reventazon Valley, which connects the Cordillera and Tortuguero ecosystems in the west, to the Barbilla and Talamanca ecosystems in the east.
The dam's constructors the Instituto Costarricense de Electricidad (ICE) were specifically bound by its financiers (The World Bank and the Inter-American Development Bank) to "restore and maintain connectivity within the Barbilla-Destierro Corridor" as a basic pre-requisite of the project's approval. The ICE were paid $2.7 million to ensure that biological connectivity was maintained, including the reforestation of a wide buffer zone around the edge of the new lake in order to assist migration. Despite this, the reforestation has been slow to happen and it is still not complete.
The Jaguar Project is working in conjunction with the ICE to help complete this vital reforestation process and restore connectivity. The ICE has donated thousands of trees which we are using to create new jungles in key areas of the biological corridor that have been deforested. In order to maximise biodiversity we are planting a wide spectrum of native tree species that are handpicked because of their beneficial effect on wildlife.
Lancaster Wetlands
THE LANCASTER WETLANDS
With the creation of the Reventazon Reservoir the most viable migration routes for large mammals across the Reventazon Valley are now the northern and southern extremes of the lake. At the southern "tail" end of the lake lie the Lancaster Wetlands, which were highlighted by environmental studies as being "the best option to restore connectivity".
The Lancaster Wetlands are a haven for wildlife that gives shelter to more than 250 species of birds and 80 species of mammals, reptiles and amphibians. Many of these species are endangered, and the wetlands are home to a higher level of biodiversity than can be found in many small countries.
In order to build the dam many tons of material were extracted by the ICE from the base of the cliff which supports the Lancaster Wetlands, leaving it in high risk of a landslide. The potential collapse of these wetlands due to this illegal extraction would be an environmental disaster for Costa Rica.
The claims concerning the dam constructor's adverse effect on the Lancaster Wetlands were investigated by the MICI (Independent Consultation and Investigation Mechanism) who found them to be true, because appropriate monitoring was not carried out. Those findings were vetoed, however, by the board of directors and the investigation by the Inter-American Development Bank has now been dropped. No action or restitution is being carried out to alleviate the environmental damage that was caused.
JUSTIFICATION FOR THE DAM
The often quoted justification for the environmental destruction caused by the Reventazon Hydroelectric Project is that it will provide clean energy and assist Costa Rica in achieving its goal of becoming carbon neutral. But is it really clean energy?
It is common scientific knowledge that areas to be flooded by Hydroelectric dams, particularly in tropical regions, should be cleared of all vegetation beforehand in order to avoid the production of greenhouse gas emissions. The ICE, however, did not clear the valley of organic matter as is clearly evident by the treetops still emerging from the lake. The lake is consequently now emitting large quantities greenhouse gases such as methane and carbon dioxide which are the principle drivers of climate change.
The greenhouse gas emissions are also being multiplied by the proliferation of an invasive species of Water Hyacinth. These plants are feeding from the contaminated waters of the Reventazon and the stagnated organic materials generated by the ICE's failure to clear the reservoir.
These facts clearly undermine the claim that the energy being produced is in any way clean or green.
The Reventazon Hydroelectric Project was marketed as an environmentally friendly, flagship "green" engineering project to be replicated throughout Costa Rica. But in reality it has now been proven to be environmentally unsound on multiple counts. It is important to Costa Rica's fragile biodiversity that the truth about the biologically destructive nature of the Reventazon Hydroelectric Project is clearly broadcast, in order to ensure that this kind of environmental damage is not allowed to happen again.
To learn more see CNN's Worldwide Report on the project, for which they consulted The Jaguar Project's Simon Macara.
