Construction work, intended to protect the city of Caen against the Orne river’s flooding, includes:

  • a 450 m long canal, intended to divert the Orne river’s flow rate of 400 m3/s in the ship canal, thanks to a control structure and to four 14.25 m wide radial gates that enable a normal water depth of 3.50 m
  • a spillway –located between the ship canal and the Orne estuary–, dedicated to releasing the diverted flow and equipped with two 10.00 m wide radial gates, used to maintain the retention height at 3.50 m
  • enlargement work on the Orne riverbed around Caen’s bridge
  • a set of cofferdams, all equipped with a lifting system
  • the automation of an already-existing radial gate
  • a local control room equipped with a PC and a secure connection, to monitor all the structures.




setec tpi carried out the design and supervision of civil engineering work and hydromechanical systems.


Key information


Client:  Joint Union for the Fight against the Flooding of the Orne river and its watershed

Design & Construction PM JV: Hydratec + setec TPI + Terrasol + BIEF + Dénicourt & Dubois

Contractors:  Quille, Mastelotto, Paimboeuf

Cost of construction: 19M€ excluding taxes

Duration: 2001 – 2003


©setec tpi

In a Nutshell

A gravity dam set in an estuary

Design of a gravity dam grounded superficially on compressible soils, in the immediate vicinity of a ship canal and set in an estuarine area subject to the tidal range of the English Channel.

Maresquier spillway:

  • 4 gates, all of which are 14.25m wide
  • 6500 m³ of concrete
  • 770 tons of sheet piles
  • 65 tons of gates and valves
  • 100,000 m³ of earthworks


Channel of the peninsula:

  • 3 drills
  • 55,000 m³ of earthworks
  • 3200 tons of sheet piles