Bouygues Construction subsidiary Bouygues Travaux Publics has been awarded the SIAAP ⁽¹⁾ contract for extending the Grésillons sewage treatment plant in Triel-sur-Seine, west of Paris. Work under the 312 million euro deal (of which the Bouygues Travaux Publics share is 90 million euros) will be carried out as part of a consortium whose members also include OTV, Stéreau and Spie Batignolles TP.

As lead firm for the civils package, Bouygues Travaux Publics will be in charge of earthworks and civil engineering for the plant, construction and fitout of the buildings, and roads and related works. Staff housing will also be built for SIAAP personnel operating the plant. The project will run for three-and-a-half years, broken down into six months for design, 26 months for construction, and 10 months for commissioning and monitoring. Close to 600 people will work on the project at peak times.

This is the second phase of the overall project. The first phase, also built by Bouygues Travaux Publics, was inaugurated at the start of 2008. The extension will triple the plant’s capacity, taking it from 100,000 cubic metres to 300,000 cubic metres of wastewater per day. This means it will be capable of handling the daily sewage discharge of a population-equivalent of 1.5 to 2 million people. And in 2012 it will meet very strict discharge requirements in compliance with the objectives of the European Union’s Water Framework Directive (WFD). Attesting to the quality of its construction and the very low environmental impact it will have, the plant will qualify for High Environmental Quality (HQE^®) certification.

The water sector represents 30 to 40% of Bouygues Travaux Publics’ annual sales in the greater Paris region: construction of treatment plants, sewer rehabilitation, construction of sewage outfalls, etc. Since 2000 the company has handed over a considerable number of projects (for both sewage and drinking water), including the plants of Colombes, Valenton, Carrières-sous-Poissy, Ivry-sur-Seine, Joinville-le-Pont, Méry-sur-Oise and Saint Cloud, all located in the Paris region.

⁽¹⁾ Syndicat Interdépartemental pour l'Assainissement de l'Agglomération Parisienne (Paris region sewage authority)