Wolffkran Crane Solution Tackles Tight-Space Dam Upgrade

Wolffkran cranes were deployed for the major rehabilitation of the Barrage de Lavalette in the Haute-Loire, where extremely confined conditions and ongoing traffic create complex logistical demands.

The project, led by Legendre Génie Civil, relies on a WOLFF 7534.16 Clear mounted on a City Portal. Operating since March 2025, the crane features a 40-m jib, 20.4-m hook height and 16-ton maximum lifting capacity, supporting temporary works as well as the removal and installation of floodgates.

Works include the full replacement of three gates from the 1950s and modernization of a fourth from the 1990s. “The dam crest is only 6.7 meters wide, which made crane erection and delivery logistics a demanding task,” said Cécile Caron. Wind gusts exceeding 45 km/h extended assembly to around 3.5 days.

As a public road runs across the dam, the crane stands on a City Portal 520, enabling vehicles to pass underneath. Load distribution beams were first installed to spread forces across the crest, before a 90-ton mobile crane erected the portal and tower crane. Although weekday road closures apply from 9 am to 2 pm, lifting over live traffic is prohibited, so all operations must occur within this window.

One demanding phase involved dismantling a 51-ton counterweight block, cut into sections of up to 16 tons for lifting. According to François-Xavier Béthuel of Legendre Matériel, Wolffkran was the only supplier able to provide crane, portal, assembly and long-term service as a single package for the 24-month project.