A special biotesting experiment has been launched at the new structures of the aeration station.

      The Joint Utility Operator JSC is completing the commissioning works (CWR) of biological wastewater treatment processes following the reconstruction of the facilities of the first technological phase of the Nizhny Novgorod Aeration Station (NAA). Already, the facilities of the first phase are treating discharges to design parameters. Alongside laboratory quality control of wastewater, specialists and ecologists are conducting an experiment with biotesting – river crayfish have been introduced into the treated water in the secondary settling tanks, and the station workers have been observing their life for a month now. "The logic is simple: we took crayfish that live in the Volga to understand how well the treated water after the secondary settling tank corresponds to their habitat. We made a special box, populated it with crayfish, and are monitoring their health and development. For us, this is a biotester that will allow us to respond in a timely manner if something is wrong," commented Elmurod Rasulmakhamedov, executive director of the Russian Ecological Movement and member of the Public Council under the Ministry of Natural Resources of the Russian Federation. According to Svetlana Maskaleva, the general director of the contracting organization engaged for the commissioning works on biological treatment at NAA, the result of the CWR is the quality of wastewater treatment at the outlet from the reconstructed secondary settling tanks. "It is well known that crayfish live in clean water. And we want to see if they will live in wastewater after the secondary settling tanks. So far, this experiment proves that the discharges are being treated consistently. They enter the Volga in accordance with all parameters. If there were spikes in pollution, the crayfish would not have survived for such a long period," Svetlana Maskaleva reported.

      Reference. The Nizhny Novgorod Aeration Station is the largest wastewater treatment facility in the Nizhny Novgorod region, with an average daily inflow of over 500 thousand cubic meters. For the first time since its construction in 1974, a large-scale modernization is being carried out. The works began in 2022, are divided into phases, and are conducted without stopping the acceptance of wastewater. The first phase of reconstruction, which included 50 facilities, will be completed in 2025. The second phase of reconstruction of NAA will begin in the summer of 2026 and will include 60 facilities, including the construction of two new ultraviolet disinfection stations. Upon completion of the second phase, the technology for processing sludge will be completely changed, which will include two-stage dewatering and thermal drying, allowing for the abandonment of the outdated technology of placing sludge on special sites at the station's landfill.