Technicians from the Provincial Council of Gipuzkoa have visited locks for operating fish in Santa Eulalia (Zamora) and Maule (France). The objective has been to know in a direct way its design characteristics and the accumulated experience on its maintenance, effectiveness, etc. With this information, the design of a fish sluice in the CH Olaberri dam is being finalized, the first obstacle that salmon must overcome when they come back from the sea.

In Zamora, several facilities have been visited on the Esla and Duero rivers. The one that is most related to the proposal for the Leitzaran is the Santa Eulalia de Tábara lock. It is an unusual device, a pioneer in the Peninsula, which allows fish with poor swimming capacity to save a 9-meter drop.

Thanks to the explanations offered, it was possible to understand the operation of the installation, and, in particular, the regulation of the gates to enable the transit of the fish in the most effective way possible. Likewise, the operation of the passage control system was observed through cameras, the illumination of the interior of the sluice to make it more attractive to the passage of the fish and the records for access to its interior in order to perform the corresponding maintenance.

The visit to Maule-Lextarre has focused on fish tracking equipment. In this town they have a fish scale and an automatic camera-based tracking system and computerized image processing for fish detection.

The technical exchange has been completed with visits by Maule officials to the Olaberri dam to discuss follow-up proposals on the ground. The result of these meetings has been very satisfactory, providing interesting proposals for design and maintenance, as well as establishing contacts of interest for the project.