ABSTRACT
The creation of an additional PKW spillway at La Raviège dam was required according to the update of the 1000-year flood hydrological studies. Huge works were necessary to built this new structure on the top of the existing dam: 1000 m3 of dam concrete were demmolished, the new spillway was built and as well as a new road bridge over the crest of the dam, and a stilling basin to protect the structure’s downstream toe and guide the flow. The new PKW has been on service since 2015. However it has not spilled yet. The feedback from other PKWs built at EDF facilities in France since 2006, was used to build this new PKW. The methods, equipment and tools have improved and have been adapted to ensure the safety of the workers and faster execution. Treating the contact between the old and new layers of concrete and the continuity of the dam block joints in the PKW are two important issues in ensuring the safety, stability and watertightness of this new structure and therefore its durability.
