Experiences in Latin America of Sediment Handling in Daily Peaking Reservoirs using Hydrosuction

Daily peaking reservoirs of small and medium hydropower plants have an increasingly relevant function for balancing new renewable energy sources. Nevertheless, sedimentation is reducing water storage capacity and affecting the operation of daily peaking reservoirs, especially in Latin America, where rivers have the capacity to transport large amounts of sediments. This context is creating a need for environmentally friendly solutions for sediment handling in hydropower plants.

SediCon, a Norwegian company specialized in sediment management, has been developing and improving hydrosuction technologies for sediment removal. Hydrosuction is a gravity powered flow of a water-sediment mixture that allows sediment removal in a controlled and continuous way without requiring external energy input. These technologies have been implemented in several hydropower plants in Latin America with outstanding results, especially for daily peaking reservoirs.

The peaking reservoirs of Doña Julia HPP (18.5 MW) and El General HPP (40 MW), located next to one of the largest protected forests of Costa Rica, were cleaned out with hydrosuction dredges. Other two hydrosuction dredges are now fixed installations in the reservoirs of two hydropower plants: El Canada HPP (47 MW, Guatemala) working continuously since 2012, and more recently in Paso Ancho HPP (7 MW, Panama).

The experiences in these hydropower plants have proven that gravity powered technologies are a reliable and environmentally friendly tool to deal with the sediment-related challenges, making possible to recover water storage capacity, reducing operational costs and increasing the efficiency of the energy production.