The dam's reservoir is situated at an elevation of approximately 880 meters above sea level.
It is managed by EDP (Energias de Portugal) as part of a larger interconnected hydroelectric system.
The reservoir area is known to contain significant deposits of sediment that have accumulated since its construction in the mid-1960s.
The dam supports the Venda Nova II power station through a complex series of tunnels and pressure conduits.
During periods of severe drought, the water level fluctuations can reveal submerged terrain features that are typically hidden.
The construction of the dam required the relocation of infrastructure to accommodate the flooding of the valley floor.
The Dam of Pisões, also known as the Alto Rabagão Dam, is a concrete gravity dam located in the municipality of Montalegre in northern Portugal. It impounds the Rabagão River to create the Alto Rabagão Reservoir, which serves as a critical component of the national hydroelectric power grid. The reservoir covers approximately 2,200 hectares, making it one of the largest bodies of water in the region. The dam reaches a height of 94 meters above the foundation and spans a crest length of 1,850 meters. Its primary purpose is electricity generation, though the surrounding area is frequently used for water sports and recreational fishing. The infrastructure is integrated into the Peneda-Gerês National Park periphery, offering views of the Serra do Barroso landscape. It functions as a significant water storage facility within the Cávado River basin.
The mid-point of the dam crest provides a panoramic view of both the spillway side and the expansive reservoir basin.
Bring wind-resistant clothing as the exposed crest of the dam experiences high winds even on clear days.
Ensure your vehicle has adequate brake fluid and tread, as the mountain roads leading to the dam involve steep gradients.
Pack binoculars if visiting for birdwatching, as the reservoir attracts diverse migratory species.
Do not attempt to swim in the reservoir, as hidden currents and cold temperatures pose significant risks.
Respect private land borders around the reservoir; remain on public access paths and designated viewpoints.
