St. Petersburg wastewater treatment upgrade continues

The project will benefit some 410,000 people, and is expected to reduce discharges of phosphorus into the Neva River and the Gulf of Finland by some 40 tonnes per year – a figure equivalent to the discharge of untreated wastewater by more than 53,000 people per year.

St. Petersburg's wastewater treatment system has been substantially improved and upgraded during the last ten years. The first tests on improving biological phosphorus removal, which were supported by the Finnish Ministry of the Environment, were carried out in the area during the mid 1990’s. In 2000, this cooperation was extended to the chemical removal of phosphorus.

Largely as a result of these measures, phosphorus discharges have been reduced in the bigger wastewater treatment plants by 50 percent during the last ten years.

“Our cooperation with Vodokanal on the protection of the Baltic Sea has been exemplary and produced impressive results”, says Hannele Pokka, Permanent Secretary at the Finnish Ministry of Environment. According to Pokka, the St. Petersburg project has proved that the chemical removal of phosphorus is a cost-efficient and reliable process, which should be extended to other wastewater treatment plants in the area.

Currently, almost 85 per cent of St. Petersburg’s wastewater is treated and this figure will rise to 94 per cent when the Northern Collector System will come on stream. ”This project is intended to solve all the nutrient discharge problems emanating from the City of St. Petersburg, for once and all, and after the modernization process, the city will comply with all the recommendations laid out by HELCOM," says NEFCO's Vice President, Kari Homanen.

According to the Finnish Environment Institute, improved wastewater treatment in St. Petersburg will drastically improve water quality, promote biodiversity and reduce the spread and proliferation of toxic algae (cyanobacteria) in the Gulf of Finland.

News source: RECYCLINGPORTAL