Water testing at Concordia

ESA medical doctor Sarah Gaier, member of the DC22 winterover crew, tests water samples from the Grey Water Treatment Unit (GWTU) at the Franco-Italian Concordia research station in Antarctica.  

Located on an icy plateau at an altitude of 3200 metres in Antarctica, Concordia is one of the most isolated research facilities on Earth. During the winter, a small crew is cut off from the rest of the world for almost nine months, enduring extreme cold, prolonged isolation and near-constant darkness. 

In such conditions, careful water management is essential. Built by the French company Firmus for ESA and the French space agency CNES, the GWTU system was installed at Concordia in 2005 and recycles up to 85% of the station's wastewater. This includes water from showers, laundry and drinking water fountains. Even part of the station's black water, or toilet water, can be recovered by converting as much of it as possible into grey water. 

The recycling process involves several treatment stages. Water passes through a ceramic honeycomb filter, followed by a pair of membranes, then additional filtration and ultraviolet radiation eliminate any remaining bacteria and impurities. The system reuses the recycled water for technical and hygiene purposes, while it produces drinking water separately by melting clean, unpolluted snow. 

ESA medical doctors at Concordia play a key role in maintaining this system. Alongside their research supporting future human space exploration, they regularly analyse water samples taken at different points in the recycling process. Tests measure parameters such as ammonium and phosphate levels, conductivity, acidity and bacterial content. During the busy summer season, when the station population can increase to around 80 people, the medical doctor monitors the water quality more frequently. 

Concordia is operated by the French and Italian Antarctic research programmes, IPEV and PNRA, whose support has been essential to the recycling system's long-term validation in this extreme environment. The system has now also been used to support remote communities on Earth and even recycle water at the French tennis tournament Roland Garros. The proven technology could one day help sustain astronauts during the long journey to Mars.