The aera of the Tarn-et-Garonne department
Nègrepelisse
The Tarn-et-Garonne department is composed of very different rural regions. The north-east offers in itself a contrasting landscape of alluvial plain and the first foothills of the Massif Central bordering with the Aveyron department.
The small towns (Nègrepelisse, Vaïssac, Septfonds…) are equipped with communal wastewater treatment plants; yet, on-site sanitation mainly prevails due to the scattered settlements and the soils aptitude to spreading..
Currently, the north-eastern part of the department (49 villages) is not served by any septage treatment unit except for the western tip, where septage is treated in the wastewater treatment plant of Montauban. A 2009 survey revealed an interest in establishing an on-site treatment system in the sector of the Chemin des Courounets in Nègrepelisse. Some advantages of this site:
- central position with regard to the on-site sanitation sectors
- easy access from the main roads
- complementarity with the existing installations of Nègrepelisse’s WTP.
The septage loads to be treated are estimated on SPANC’s inventory of on-site sanitation statement of the area and on a 20-year forecast.
| Parameters | Unity | Actual CCTVA | Actual others | Actual total | Increase total | Future total |
|---|---|---|---|---|---|---|
| Volume | m³/year | 6 171 | 4474 | 10 645 | 510 | 11 155 |
| CDO | T/year | 52.9 | 72.8 | 125.7 | 13.6 | 139.3 |
| SS | T/year | 66.2 | 54.6 | 120.8 | 10.2 | 131.0 |
CCTVA: septage collected on the CCTVA territory Others: septage collected in the north-eastern area outside CCTVA territory Total: septage collected in the entire north-eastern area Total increase: additional septage collected in the entire north-eastern area in the next 20 years Future total: septage collected in the entire north-eastern area in 20 years
