Treating wastewater
Facilities designed by Stereau guarantee that all treated water discharged into the natural environment is safe and has no negative impact on biodiversity. As the world addresses the issue of climate change, our solutions also allow you to reuse wastewater efficiently and effectively to conserve your water resources to the maximum.
Our approach
From the research phase right through to project delivery and operation, Stereau addresses the imperatives of sustainable development to deliver measurable results :
- Straightforward UV disinfection may be sufficient to comply with French regulations, especially when the secondary treatment includes a membrane filtration solution, such as AquaRM®.
- To remove micropollutants like pesticides and drug residues, we offer more advanced technologies, including the CarboPlus® process.
- To remove salts and pollutants, our reverse osmosis technique purifies water for domestic and industrial use.
- Electrodialysis is effective for removing excessive salinity (e.g. upwelling of seawater to pollute groundwater).
Our solutions
- Primary settling
- Moving Bed Biofilm Reactor or Sessile bacterial bed
- Prolonged aeration
- Biofiltration
- Membrane settling or filtration
- Reverse osmosis
- Electrodialysis

Re-use of treated and purified wastewater: a real alternative to water stress
REUT – the Re-use of Treated and Purified Water – gives you the opportunity to recover and use your treated wastewater for irrigation, whether for agricultural crops, golf courses or urban green spaces. It can also be used for road cleaning and car washing, to artificially top up groundwater levels or for firefighting.
“In a region where water resources are scarce, the ability to reuse treated wastewater provides the perfect response to the island’s seasonal influx of tourists”.
Arnaud Thiesse, International Director
As the designer, builder and operator of the Vathia-Gonia wastewater treatment plant in Nicosia, Stereau has delivered significant savings in drinking water production by reusing wastewater treated and purified using membrane filtration technology. The resulting water is used for watering green spaces, industrial processes, irrigation and groundwater top-ups.
In Djibouti, Stereau and Colas Djibouti joined forces
to build the new Douda wastewater treatment plant (40,000 population equivalent
capacity). The treated wastewater from this plant is used to irrigate 400
hectares of forestry and farming crops. The residual sludge from the
purification process is used as fertiliser to improve agricultural land.