The waste water treatment plant at the French community of Léry was officially inaugurated on June 23rd 2011. A consortium led by consulting and engineering firm DHV completed the water treatment plant under a Design & Build contract with a total value of EUR 20 million.

More capacity
The new plant has a capacity of 60,000 p.e. (population equivalent) and replaces an old physical chemical plant with insufficient capacity that could not meet the European standards for effluent quality. The effluent of the new plant is first revitalized in various ponds and watercourses on site, and is then discharged into the Eure, a tributary of the Seine River. The sewage sludge is composted in a newly built composting plant adjacent to the water treatment plant.

Integrated in environment
As the plant is situated in an area that is also used for recreation, the project’s principal – Communauté d’Agglomération Seine Eure (CASE) – had set high standards for the plant’s design. DHV project leader Hans Hekelaar is happy with the result: ‘The plant has turned out wonderful. Wherever possible, we have used natural materials, and we have made sure that the plant is properly integrated into the environment.’ A heat pump is used to heat and cool the plant building sustainably.

DHV was the consortium’s mandataire, i.e. being the joint and severally liable party and spokesperson. Other consortium members were Demathieu & Bard for the civil works, and Sources was responsible for engineering, supply and installation of mechanical and electrical works and coordination on-site..

Piste pédagogique
A so called ‘Piste pédagogique’ (a safe route with information panels) has been integrated into the plant, allowing school pupils and other visitors an up close look at the plant’s features and functions.

The project was funded by CASE, Agence de l’Eau Seine Normandie, and the Conseil Général of the Eure department.

DHV is a leading international consultancy and engineering firm, providing services and innovative solutions in Transportation, Water, Building & Industry, Urban and Regional Development, and Environment & Sustainability. DHV, headquartered in the Netherlands, is part of the DHV Group which maintains a network of 75 offices worldwide. The DHV Group has a staff of 5,300 and its turnover in 2010 was € 469 million.

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