“Melbourne” basin supply system (France)

Construction of a flood relief basin

Client: Lille Métropole - Model scale: 1:14.5



In order to combat urban flood risks, Lille Métropole urban area council intends to build a flood relief basin in the town of Tourcoing capable of storing 25,000 m3 during a rainfall event. This basin will be fed by various storm sewer outfalls on the existing network, with a maximum flow rate of 11.6 m3/s. Given the complex nature of the flows within the structure (weirs, diversion, vertical shafts, etc.), Lille Métropole wishes to have its dimensional design validated through a physical scale model study.

Aims of the physical scale model

The objective of the model is to validate and optimise the hydraulic operation of the structure:

  • Operation of the feed structures (frame, pipe)
  • Efficiency of a weir-type system for distributing flows between a pollution compartment (sand traps) and a flood compartment;
  • Operation of the sand traps;
  • Operation of the vertical shafts;
  • Characterisation of operation in downgraded conditions (blocked screen rake)

Description of the physical scale model

The physical scale model offers a means of representing all the project components:

  • Supply framework (DO1) and supply pipe (DO2);
  • Flow distribution chamber with its equipment (screen rakes, weir, etc.)
  • Sand traps, scum baffle and vertical shaft in the pollution compartment;
  • Feeder canal and vertical shaft in the flood compartment.