Work has today begun on the partial demolition of the Olloki dam and the removal of this obstacle from the River Leitzaran in Gipuzkoa.

In the previous phase which took place last year a nearby stream, called Santolaz, was stabilised with a stone ramp and a groove was made in Olloki so that built-up sediment could begin to move.

Now work will begin to shore up the access track to a functioning hydroelectric power plant (CH Santolaz) and partially remove the dam that, at 7m tall, created a very significant barrier for the Leitzaran ZEC ecosystems. Two thirds of the current dam will be retained as testimony to the industrial past of this area. The 18m wide channel that will now be created is sufficient to allow the ecological processes of the River Leitzaran, previously interrupted by the dam, to be restored. This partial demolition strategy seeks to maintain a balance between ecological restoration and the conservation of the Cultural Heritage.

Currently, Olloki Dam is the first impassable obstacle encountered by species such as the Atlantic salmon when they migrate from the sea to breed. Thanks to this initiative, the entire Gipuzkoan stretch of the River Leitzaran will be released: more than 25km of river habitats will once again be available to this emblematic species.