Flood spillways of Laye Dam (France)

Study of the old and new spillway

Client: Syndicat Intercommunal d’Irrigation de la Région de Forcalquier - Echelle: 1:50

Context

As part of its complete project management mission for the construction of the new spillway of the Laye dam (embankment dam, used for irrigation), ARTELIA carried out a physical scale model study of the spillways (existing and projected), in order to confirm the conclusions of the 3D numerical modelling and, if necessary, to adapt the hydraulic sizing of the structures.

Aims of the physical scale model

The aims of the model are :

  • Establish the rating curve of the new spillway (lateral labyrinth weir)
  • Verify the operation of the proposed structures (water surface lines, flow velocities, energy dissipation)
  • Identify the possible interactions between the outflows of the existing and projected spillways.

Description of the physical scale model

A part of the reservoir upstream of the dam and the spillways are modelized. La Laye riverbed over a section of approximately 180 m downstream of the dam is modelized.

  • Existing spillways: morning glory spillway equipped with a mobile cylindrical gate, water intake tower with bottom outlet, gallery crossing the dam and its release structure
  • Projected spillway: lateral labyrinth weir and its collecting trough (31 m), smooth chute (133 m, 0.5%), stepped chute (28 m, 60%), dissipation basin (36 m)