Bajo Frío Hydroelectric Dam
Description of social and environmental performance.
For the construction of works of large dimensions, as is the case with the Bajo Frio Hydroelectric Generation Centre in Panama, earthwork has to be carried out using heavy machinery. This, together with other construction activities, affected soil compaction and the vegetation that grew over it, converting it into degraded soil, with no permeability or microbial activity and few nutrients, particularly in areas reserved for infrastructure installation which required more extensive earthworks.
In order to promote soil regeneration, we opted for vermicomposting; a clean technique that transforms organic waste into a material high in nitrogen, potassium, phosphorus, magnesium, minerals and micronutrients with a better uptake and water retention capacity. If the optimal conditions for the worms to develop are created, they can produce excellent quality compost without having to form stacks and transfer them to palates.
Two species of red worm were used for the composting process: Eisenia fetida and Lumbricus rubellus. These are very appropriate and effective due to their growth and reproduction rates.
The use of earthworms is a clear sustainable alternative for soil regeneration.
The application of this vermicomposting process helped the regeneration of the compacted soil caused by construction activities, restoring its physical and biological properties. This technique improved soil permeability, both for air and water, increased water retention and the capacity to store and release nutrients required by plants. In addition, as a result of its biological activity, the soil began show a high microbial load, key for stimulating the vegetation growth. Had it not recovered, this soil would have had to be treated as a waste, and managed and transported to the authorised landfill. This was avoided with the vermicomposting.