Drinking water treatment plant

Wastewater collection and treatment
The wastewater is collected and sent to the association’s treatment plant on Route de Seignosse.
The network is 125 km long and carries 1 million m3 of wastewater along with approximately 500,000 m3 of infiltration water (groundwater drainage, non-compliant connection, etc.).
The low points on the network are fitted with upflow units (over 70 units).
Tosse has been connected to the association since June 2013.
Over the next few years, work will be focused on detected bad connections.

The SIEAM wastewater treatment plant (drinking water treatment plant)
The Marensin wastewater treatment plant was brought into service in 2007. It is intended to treat the association’s residual water to a capacity of 100,000 equivalent inhabitants, which corresponds to pollution during the peak summer period.
The level of discharge from the Marensin wastewater treatment plant has to meet the targets fixed by the Prefectoral Order of 9 January 2006.

The treatment networks are as follows:


Water network
- Three upflows of effluents from the main units in Soustons (Nicot and Hardy) and Vieux Boucau via two DN300 and one DN250 pipes.
- Pre-treatment: two automatic screens, max. Q = 1400m3 per hour, effective width of the plates = 5mm. The matter held back by the screens is then sent via a compacting screw to be stored in a container
- Desilting pond/degreaser: the effluent passes through two cylindrical/conical structures, each aerated by a submerged turbine. The fine air bubbles emulsify the lightweight matter and fats, which rise to the surface. The extracted fats are sent directly for biological treatment. The silt, which collects at the bottom of the structure, is sent to the silt treatment unit (classifier).
- Flow restrictor with adjustable spillway
- Aeration pond: this contains three concentric areas that may have different uses depending on the season and the desired results (Anoxia: 1000m3, Anaerobia: 1490m3, Aerobia: 8850m3)
- De-aerator
- Two clarifiers
- Industrial water tank
- Two buffer ponds
- Wastewater canal
- Outflow pumping station
- Infiltration site: 4 lagoons, each 1450 m²

Sludge network
- Recirculation
- Sludge thickener silos
- Centrifuges
- Composting platform

Secondary structures
- Operating buildings
- Emptying of drainage and cleaning matter
- Generator house

An educational circuit has been set up at SIEA’s Marensin wastewater treatment plant.
Another educational circuit for drinking water has been set up at the Peleusec treatment plant.
For further information or a visit, please contact the secretariat
on 05 58 41 43 15 or by email: This email address is being protected from spambots. You need JavaScript enabled to view it.

1, square d'Aquitaine - BP 55 40141 SOUSTONS Cedex contact@sieam40.fr 05 58 41 43 15 Lundi - Vendredi : 08h00 - 12h00 / 13h30 - 17h30