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A flagship wastewater treatment site

Upgraded by Veolia in accordance with the requirements of the European Directive on good ecological status of water, the Marquette-lez-Lille station is a technological reference and a model of sustainable development.

High tech water and sludge treatment

Launched in Feb 2013, Ovilléo, the new wastewater treatment plant in Marquette-lez-Lille, has a capacity of 620,000 PE (population equivalent). It treats wastewater discharges by ensuring compliance with the new European standards, which include nitrogen and phosphorus in addition to carbon components. It also deals with stormwater, which was not the case before.

In parallel, Ovilléo uses an innovative thermal hydrolysis method to reduce the amount of sludge produced and increase the production of biogas. Results: a low carbon footprint and almost total provision of the thermal energy needs of the plant. Furthermore, after drying, the sludge becomes a valuable resource for re-use in agriculture and cement manufacture.

Perfect integration into the urban environment

Process were applied for noise and odour reduction. This effort to achieve "zero harm" is also embedded into the construction of the plant. The design of the new plant has made the whole site  more compact freeing up seven acres of land which have been  transformed into an educational garden. The buildings blend into the environment as they are covered with vegetation and no tank is exposed to the open air.

In addition to the well-being of residents, the Ovilléo project also integrated the employees. Staff at the plant were from the old station and skills training were organized for technicians in partnership with Campus Veolia.


20%-40% reduction in sludge production

94% of thermal energy requirement provided by biogas

Customer benefits

  • Reduction of 20 to 40% of the sludge produced
  • Thermal energy needs covered 94% by biogas
  • Integration into the environment
  • Educational garden of seven hectares


  • Wastewater Treatment
  • Energy and material recovery
  • Environmentally sensitive design and construction