Its implementation

Implementation process

Construction of the new plant started in June 2008 and ended in February 2009, despite exceptionally heavy rainfall.

Construction etage de filtre planté à circulation verticale

It required 9700 m² of geomembrane, 3300 m of drainage pipes, 112 ventpipes, 12 000 tons of sand and gravel, 16 600 reeds, 26 pneumatic valves, 900 m of fence etc. 800 truck rotations were necessary only to supply the plant with sand and gravel.

The ponds remained operational during construction to ensure continuity of wastewater treatment.

Some additional work:

  1. renovation of the pumping unit and pressure pipe of La Coujoune between the town and the plant site over approx. 2 km
  2. renovation of the pond inlet system
  3. planting of hedges around the new plant
  4. sustainable rectification of the Montrosies stream.

Renovation of La Coujoune pumping unit required the construction of a new 6-m deep well adjoining an existing building without interruption of the existing unit.

The main stakeholders

The contracting authority

logo du CCTVAThe contracting authority is the equivalent in public French law to the owner in private law. The contracting authority of the WTP is the Communauté de Communes des Terrasses et Vallée de l’Aveyron-CCTVA. President: Mr Jean Cambon, mayor of Nègrepelisse.

Consult CCTVA’s website


The construction manager

Logo Ginger Environnement InfrastructureThe construction manager is responsible for the design and monitoring of the project.Construction management for Nègrepelisse’s WTP (and St-Etienne-de-Tulmont WTP) was ensured by Ginger Environment & Infrastructure-GEI, a branch of the engineering group Grondmij, headed by Mr André Paulus, Civil Engineer, author of several technical publications on the constructed wetland system and of one popular scientific book: Constructed wetland or the green side of wastewater treatment, Le Rouergue publishers, 2011.

Consult the website on this book



Logo du SATESE 82SATESE is a service of the Department Council in charge particularly of technical assistance to sewered sanitation and on-site systems. It manages the sanitation system of Nègrepelisse since its creation. SATESE 82 advises the contracting authority in programming and monitoring aspects of renovation projects. Its Manager is Mr Jean-Sylvain Bois.

Consult the webpage of SATESE 82


The builder

Logo Epur NatureImplementation was ensured by a consortium headed by Epur Nature, pioneer and national leader of the constructed wetland system in France with several hundred realizations. Epur Nature is managed by its founder, Mr Christian Piétri. Civil engineering work was conducted by Causse & Brunet, an important groundwork and pipe contractor of the Tarn-et-Garonne department.

Consult Epur Nature’s website


roseaux intégrés dans le paysage

The Communauté de Communes des Terrasses et Vallée de l’Aveyron constructed and runs the plant.


Read the article
station écologique en cours de réalisation
The WTP’s construction

The wastewater treatment plant’s photos during the constuction.


View le diaporama