Additional Info
In operation since: 2010
Type of wastewater treated : Domestic
Hydraulic load: 400 m3/d
Organic load (PE): 1950 PE
Location : Saint Sulpice la Foret, Bretagne – France
Client : Town of Saint Sulpice la Foret
Stage 1 type : Vertical flow reed bed system (French system)
Stage 1 surface area (m²): 2,400
Stage 2 type: pond
Stage 2 surface area (m²): 5,000 m²
Stage 3 type: Vertical flow, unsaturated
Stage 3 surface area (m²): 1,950 m²
Stage 4 type: willow plantation
Stage 4 surface area (m²): 10,000 m²
Cost : 750,000.00 €
Designed by SINBIO
Needs
A three series of three waste stabilization ponds was present in Saint Sulpice la Foret. With population development, it was needed to boost the capacity of treatment while remaining on the same site and surface area. The client wished to remain with an extensive treatment system.
Solution
Two stage reed bed filters, fed by pumping, with an intermediate pond fed by gravity and infiltration in a willow plantation fed by flow siphon. There is no primary treatment; the raw, only coarse screened sewage is fed directly on the first stage beds with the storage of the filtered dried and mineralized solids for at least 10 years. A stromwater overflow has been created upstream of the pumping station towards the pond in order to allow storage before treatment of stormwater.
Benefits
Addition of reed bed filter permitted boosting of treatment capacity. Willow plantations are working like Vegetated Polishing Zone with phosphorus adsorption and water infiltration.