The Nègrepelisse WTP-The facts

The wastewater plant treats Nègrepelisse town’s wastewaters before discharging into the Montrosies, an Aveyron’s affluent. The plant’s presentation with some figures.

 

General facts

Nominal capacity : 4000/6000 PE (a plant of 4000 PE extensible to 6000 PE afterwards)
Opened in January 2009
Contracting authority : Communauté de Communes des Terrasses et Vallée de l’Aveyron – CCTVA
Project engineer : Ginger Environnement Infrastructures – GEI
Constructor : Epur Nature  
Associated firms : Génie civil Causse & Brunet, Membrane SODAF GEO, granulats RUP, postes de relevage EXEDRA et ABS

Technical facts

Receiving water : Montrosies stream, affluent of Courounets, affluent of the Aveyron river
Rejection norm : BOD < 25 mg/l ; CDO < 125 mg/l ; SS < 35 mg/l
Winter serie: VFCW1 (vertical flow constructed wetlands)+ VFCW2
Summer serie: VFCW1+ primary ponds+ VFCW2
Dimensions: 1.2 m²/PE (filtre 1) + 2.5 m²/PE (ponds - 15 000 m²/6000 PE) + 0.8 m²/PE (filtre 2)

 

Performances : Consult the file The Nègrepelisse WTP - The performances
Particularities :

1. biggest capacity  in France (when it opened)
2. the primary pond is totally conserved and intergrated into the treatment steps (summer serie)
3. motorized guillotine gate with a pneumatic command
4. in case of the plant’s dysfunction the raw wastewaters are stored on the old pond

The integration of the primary ponds in the treatment steps (only during summer) improves the rejected water quality during the low water period therefore the most sensitive period for the receiving water.

Economical facts

Only the treatment plant (except adduction), from 1 to 4000 PE.
Implementation cost: 1 634 000 €HT or 411 €/PE
Planned running cost: 4000 PE x 10 €/PE = 40 000 €/year
Real running cost (except extraction of sludges and renewal costs): 36000€/year

Consult
all the files's list