In October 2016, the Vyborg wastewater treatment plant deployed advanced phosphorus removal, after which the phosphorus concentrations in wastewaters leaving the water utility were reduced to the level recommended by the Baltic Marine Environment Protection Commission HELCOM (0.5 mg of phosphorus per leaving litre of wastewater).
Vyborg has approximately 80,000 inhabitants. The wastewaters of the city run through the Bay of Vyborg directly to Finland’s coastal areas, which means that phosphorus removal will improve the status of both the Bay of Vyborg, and the eastern marine areas of Finland. Advanced nutrient removal will reduce the share of the annual phosphorus load of the Gulf of Finland ending up in the Bay of Vyborg by approximately 20 tonnes. This is almost as much as the annual discharges from the wastewater treatment plant in Viikinmäki, Helsinki.
The delivery, installation and construction works of the plant’s phosphorus removal system were completed in July–October 2016. In this joint project of the Vyborg Water Utility and the John Nurminen Foundation, the Foundation was responsible for procuring the equipment for advanced phosphorus removal, while the water utility took care of the costs of installation and construction. The total costs of the Foundation’s subproject amounted to approximately €140,000.
Joint project launched in 2010
In June 2010, a memorandum of understanding was signed with the Vyborg Water Utility on improving the efficiency of phosphorus removal, together with an agreement to carry out phosphorus removal tests at the treatment plant. In the winter of 2010 – 2011, the tests were conducted with equipment delivered by the Foundation, and financing from the Finnish Ministry of the Environment. Based on test results, a technical process plan was drawn up in 2011, together with tendering documentation for improving the efficiency of phosphorus removal at the Vyborg plant.
An investment agreement with the Vyborg Water Utility was signed in the spring of 2012. The implementation of the agreement was, however, delayed due to the constant changes in management at the Vyborg Water Utility, and a breakage in the treatment plant’s main sewer pipe. In February 2014, Vyborg celebrated the completion of a new header pipe, after which the implementation of chemical phosphorus removal could be continued. Phosphorus removal began in the autumn of 2016.