Lagooning and sewage treatment

Traitement professionnel des eaux usées par lagunage

For more than 20 years, SEDE has been offering various curing techniques. With a wide range of equipment from the big arm excavator to the caterpillar, via different amphibious means.


Whether it is a lagoon to treat urban or industrial effluents, periodic basin maintenance is necessary.

As part of normal design, a lagoon should be cured every 10 to 15 years, or more frequently in the case of a heavy load. If you notice a silting rate exceeding 30%, sludge on the surface, reduced waste quality, your basin requires work. Before each lagooning and wastewater treatment operation, SEDE offers you an expert assessment in several phases :

1.  Quantifying volumes: bathymetry

We can offer you, in advance, several bathymetry techniques. This procedure allows :

  • Accurate volume quantification
  • Definition of an appropriate budget for the treatment of wastewater by lagooning.

2. Validating sludge compliance : analyses

Nonconformities are relatively rare for small urban or agri-food lagoons, though they are always possible.

SEDE then analyses all agronomic and regulatory parameters in order to define the destination of the sludge after wastewater treatment.

3. Studying the destination of sludge

Compliant sludge is generally destined for agricultural use. In this case, SEDE proposes the regulatory files to authorise spreading :

  • Spreading plan.
  • Declaration or authorisation file.
  • Agronomic monitoring.

 4. Proposing the most suitable curing technique

Many parameters are taken into account when defining the technique to be used for wastewater treatment and lagoon curing :

  • Sludge quality and quantity,
  • Access to the basins,
  • Basins made of clay or sealed with a tarpaulin,
  • Destination of the sludge.

According to these parameters, SEDE will offer to carry out the curing and spreading with the most adapted and economical technique.